Next Article in Journal
Improving Access to Sexual Health Services in General Practice Using a Hub-and-Spoke Model: A Mixed-Methods Evaluation
Previous Article in Journal
How Media Exposure, Media Trust, and Media Bias Perception Influence Public Evaluation of COVID-19 Pandemic in International Metropolises
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
IJERPH
Volume 19
Issue 7
10.3390/ijerph19073944
ijerph-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles thumb_up
...
Endorse textsms
...
Comment
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Review

Characteristics and Influencing Factors of Polycyclic Aromatic Hydrocarbons Emitted from Open Burning and Stove Burning of Biomass: A Brief Review

by
Hao Zhang
1,
Xuan Zhang
1,
Yan Wang
1,
Pengchu Bai
1,
Kazuichi Hayakawa
2,
Lulu Zhang
2,* and
Ning Tang
2,3,*
1
Graduate School of Medical Sciences, Kanazawa University, Kakuma-Machi, Kanazawa 920-1192, Japan
2
Institute of Nature and Environmental Technology, Kanazawa University, Kakuma-Machi, Kanazawa 920-1192, Japan
3
Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kakuma-Machi, Kanazawa 920-1192, Japan
*
Authors to whom correspondence should be addressed.
Int. J. Environ. Res. Public Health 2022, 19(7), 3944; https://doi.org/10.3390/ijerph19073944
Submission received: 4 February 2022 / Revised: 22 March 2022 / Accepted: 23 March 2022 / Published: 25 March 2022
Versions Notes

Abstract

:
To mitigate global warming and achieve carbon neutrality, biomass has become a widely used carbon-neutral energy source due to its low cost and easy availability. However, the incomplete combustion of biomass can produce polycyclic aromatic hydrocarbons (PAHs), which are harmful to human health. Moreover, increasing numbers of wildfires in many regions caused by global warming have greatly increased the emissions of PAHs from biomass burning. To effectively mitigate PAH pollution and health risks associated with biomass usage, the concentrations, compositions and influencing factors of PAH emissions from biomass burning are summarized in this review. High PAH emissions from open burning and stove burning are found, and two- to four-ring PAHs account for a higher proportion than five- and six-ring PAHs. Based on the mechanism of biomass burning, biomass with higher volatile matter, cellulose, lignin, potassium salts and moisture produces more PAHs. Moreover, burning biomass in stoves at a high temperature or with an insufficient oxygen supply can increase PAH emissions. Therefore, the formation and emission of PAHs can be reduced by pelletizing, briquetting or carbonizing biomass to increase its density and burning efficiency. This review contributes to a comprehensive understanding of PAH pollution from biomass burning, providing prospective insight for preventing air pollution and health hazards associated with carbon neutrality.

1. Introduction

Polycyclic aromatic hydrocarbons (PAHs) are a group of organic compounds comprising two or more aromatic benzene rings; PAHs are ubiquitous in the atmosphere and have received much attention due to their toxicity to humans [1,2,3]. PAHs entering the human body will be metabolized by cytochrome P450 enzymes and transformed to their quinoid, epoxide and hydroxyl derivatives. Some of the metabolized derivatives show harmful biological activities that are carcinogenic and mutagenic [4,5]. Therefore, exposure to PAHs in the short or long term might cause acute and chronic harmful health effects, including asthma, bronchitis or even lung cancer [2,6].
PAHs are formed through incomplete combustion or pyrolysis of organic materials, such as fossil fuels and biomass [7,8,9]. Fossil fuels are the most widely used energy source, but their burning releases large amounts of greenhouse gases, causing global warming [10,11,12]. With population growth and urbanization, global energy demand will increase by 1.3% every year to 2040 under the current energy policy, which will exacerbate global climate change [13,14]. These rigorous energy issues and the resulting environmental pollution have impelled the transformation of the world energy structure [15,16,17]. Renewable energies (e.g., biofuels, hydroelectricity and nuclear) are considered to mitigate the greenhouse effect [18]. However, some unfavorable factors have restricted the availability of many renewable energy sources, such as hydroelectricity (which is easily affected by climatic conditions) and nuclear energy (nuclear accidents) [19,20]. Biomass fuels stand out from renewable energies due to their low cost, widespread availability and convenience of use; thus, such fuels are receiving increasing attention [21,22].
Biomass fuels mainly come from agricultural and forestry waste such as crop straw, firewood, and animal dung. Unprocessed biomass fuels are all favored fuels in many rural areas because they can be directly used to generate heat or electricity after they are acquired and can be obtained at almost no cost [23,24,25]. According to a previous report, the number of people in the world using biomass directly for cooking reached approximately 2.4 to 3.3 billion in 2018 [23]. In addition, biomass is the fuel that is most widely used in residential space heating, particularly in European countries [26]. Reports show that biomass fuels are usually burned in rudimentary stoves or heaters with poor burning conditions during daily domestic use, favoring PAHs production [27,28,29]. The report shows at least 40,000 premature deaths in Europe every year contributed by biomass combustion for residential space heating [30]. Therefore, although biomass fuel is a recommended carbon-neutral energy source during the energy transition period, the environmental and health effects caused by PAHs emitted from biomass burning cannot be ignored [31,32,33,34]. Apart from human activities, biomass burning also occurs naturally, such as forest and grassland fires caused by intensified global warming. Based on the report of Shen et al., Table 1 briefly summarized the highest PAHs emission industries around the world [35]. The PAHs from biomass burning represented a high proportion of the total emissions, which might lead to relatively high health risks. To promote the eco-friendly and healthy development of biomass fuels, it is crucial to investigate the characteristics of PAHs emitted from biomass burning and their influencing factors [36,37,38,39].
Biomass burning can produce PAHs at levels comparable to those of fossil fuel burning [40,41,42]. As shown in Table 2, the PAH emission factors (EFs) of biomass burning are similar to and sometimes even higher than those of coal burning [43,44,45], and its environmental and health impacts have attracted much attention. Moreover, PAHs emitted from biomass burning can mix with other burning products, such as lignin-derived products (veratraldehyde and vanillic acid) and flavonoid compounds [46]. Photostable compounds (e.g., lignin-derived compounds) in the mixture can inhibit the photodegradation of PAHs and prolong their atmospheric life, enabling them to be transported [47,48,49]. In addition, the enhanced bioactivation of the PAH mixture can cause severe health hazards to humans [50]. Epidemiological studies in many countries (such as China and India) have shown that emissions from biomass burning are likely to increase the prevalence of nasopharyngeal, pulmonary tuberculosis, chronic obstructive pulmonary disease and laryngeal cancer among local residents [51,52,53]. To control the environmental and health side effects from global decarbonization, a comprehensive assessment of PAH emissions from biomass burning is urgently needed.
This review summarizes the concentration and composition of PAHs emitted from biomass burning. The effects of the biomass composition, including volatile matter, nonvolatile components, potassium salts, moisture content and density on PAH formation, are discussed. In addition, the influences of temperature and oxygen supply of burning in stoves on PAH emissions are studied. This review provides a basis for future research on reducing PAH emissions from biomass burning during the global carbon-neutral transition.

2. PAH Formation during Biomass Burning

Biomass burning can theoretically be divided into four steps—dehydration, devolatilization, char burning, and ashing [55]. The burning temperature of biomasses ranges from 250 °C to 1200 °C [56]. Under the action of external heating, moisture is volatilized first. As the temperature increases, volatile components in the biomass are volatilized and are expected to be transformed entirely into CO2 and H2O under high temperatures and aerobic conditions. The remaining char in the biomass burns in the presence of adequate oxygen to form gases (mainly CO and CO2) and ashes.
However, many factors affect the complete burning of biomass in the actual burning process; these factors are mainly related to the simultaneous occurrence of theoretical burning steps [57]. For example, the transition from dehydration to devolatilization co-occurs with char burning, which decreases the burning temperature [58]; the concurrent devolatilization and char burning leads to insufficient oxygen supply for both processes [59]. The supplied oxygen reacts preferentially with volatile matter around the biomass fuel and then reacts with char in the biomass, which results in incomplete combustion of both volatile matter and char under high temperatures and insufficient oxygen conditions. These processes are beneficial to the production of PAHs.
In addition, the structural materials (such as lignin) of biomass can produce volatile gases through pyrolysis during char burning decomposition [60,61]. The volatile gases will further react with char to produce gaseous products, including small hydrocarbon radicals (such as ethynyl and 1,3-butadiene radicals) and hydrocarbons (such as propylene and butadiene) [62]. After that, the gaseous product will be converted to LMW PAHs through incomplete combustion during devolatilization. The LWM PAHs will be gradually pyrosynthesized into medium MW (MMW) and high MW (HMW) PAHs through the “zig-zag addition process” [62].
Based on the difference between the theoretical and actual processes of biomass burning, the generation of PAHs is affected mainly by biomass properties and combustion conditions. To comprehensively understand the generation and emission of PAHs in biomass combustion, relevant studies are summarized in the following sections to analyze the emission characteristics of PAHs and identify specific influencing factors.

3. PAH Emissions from Biomass Burning

According to burning methods, burning can be mainly divided into stove burning (such as industrial boilers and household stoves) and open burning (such as forest fires, grassland fires and open burning of straws). The characteristics of PAH emissions from various burning methods are different. This study is focused on the 16 PAHs listed by the US Environmental Protection Agency (EPA) as priority air pollutants among the other PAHs. The sixteen PAHs are divided into five groups based on ring number: two-ring PAH (naphthalene), three-ring PAHs (acenaphthylene, acenaphthene, fluorene, phenanthrene and anthracene), four-ring PAHs (fluoranthene, pyrene, benz[a]anthracene and chrysene), five-ring PAHs (benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene) and six-ring PAHs (benzo[g,h,i]perylene, indeno[1,2,3-c,d]pyrene and dibenz[a,h]anthracene). The 16 species receive much attention due to their prevalence, persistence and potential toxicity to humans [63]. The LMW PAHs include two- and three-ring PAHs, MMW PAHs include four-ring PAHs, and HMW PAHs include five- and six-ring PAHs. It should be noted that PAHs with different MW have different oxidative potentials in human metabolism. PAHs with a relatively high MW positively correlate with high oxidative potential, which leads to severe DNA damage and disturbances in DNA replication, causing higher health risks to humans [64,65].
Table 3 lists several studies that compared particulate matter (PM)-bound PAHs in the periods of non-burning and open burning of crop residues. The PAH emissions from biomass open burning in Hanoi, Vietnam, in spring-summer and autumn-winter show a significant increase when comparing those in the non-burning period (2.60 ± 1.31 ng/m3 and 14.1 ± 3.69 ng/m3, respectively) with those in the open-burning period (3064 ± 2370 ng/m3 and 4488 ± 3850 ng/m3, respectively) [53]. The concentrations of PAHs in other regions during the open-burning period also show massive increases; concentrations increase approximately 2.80–9.54 times compared to those in the non-burning period [41,66,67], indicating that the open burning of crop residues significantly increases the ambient concentration of PAHs, which can cause severe health effects. Unlike the artificial burning of crop straw, the open burning of biomass in sparsely populated areas is dominated by forest and grassland fires, which increase the local level of PAHs and their load in long-range transport [68,69,70,71]. Wang et al. estimated that the annual emission of PAHs from bushfires/wildfires in Australia ranged from 160 to 1100 Mg/year with a median of 700 Mg/year [72]. The PAHs emitted from wildfires reached approximately 13.6% of the total PAH emissions, and exacerbated global warming could increase the occurrence of wildfires to emit more PAHs [35].
Cooking is the most common situation where biomass is burned in stoves. Table 4 compares the PAH emissions from stove burning of biomass during the cooking period with those during the non-cooking period. The biomass burned in homemade clay-stoves called “Chulha” (no chimney) in Lucknow, India, showed higher PAH concentrations during the cooking period in summer and winter (9110 ± 3570 ng/m3 and 15,600 ± 2950 ng/m3, respectively) than during the non-cooking period (1120 ± 190 ng/m3 and 3530 ± 890 ng/m3, respectively), and the PAH emission concentrations were approximately 8.13 and 4.41 times higher during the cooking period in summer and winter, respectively, leading to severe health risks [73]. The biomass burning in brick stoves with a chimney in Laiyang, China, shows a lower increase in the cooking period (696 ± 230 ng/m3) than in the non-cooking period (513 ± 225 ng/m3) [74]. Moreover, reports show that PAH emissions based on benzo[a]pyrene equivalent quantities from biomass burning in domestic stoves for heating and cooking reach approximately 56.7%, which is far higher than emissions from coal (11.7%) [36].
In winter, burning biomass for residential heating was reported as a critical air pollutant emission source [77]. The reports in Europe and North America showed burning biomass for heating had a significant impact on the health of local residents [78,79]. Table 5 compares the particulate matter (PM)-bound PAHs during the non-heating period with the heating period. The PAHs concentration in Zagreb, Croatia in the heating period (41.2 ng/m3) was approximately 76.3 times higher than in the non-heating period (0.54 ng/m3), which significantly enhanced the health risks of biomass burning to the local residents [80]. In addition, due to the indoor biomass burning for heating, the indoor PAH concentrations were higher during the non-heating (131 ng/m3) and heating periods (461 ng/m3) than those outdoors (36.0 ng/m3 and 106 ng/m3, respectively) [81]. In a rural site in Delnice, Croatia, the PAH concentration was 2.23 times higher than the in urban site during the heating period [82]. This difference might be caused by the use of natural gas or oil for residential heating in urban areas, but biomass in rural areas.
Table 6 shows the increase in the PM-bound PAH emissions in the open-burning period compared with those in the non-burning period. Compared with normal periods, the open-burning period displays greater increases in LMW and MMW PAHs than in HMW PAHs, indicating that high levels of LMW and MMW PAHs were formed during biomass burning. In addition, the burning temperature can also lead to massive emissions of LMW and MMW PAHs. Table 7 shows the ignition, peak and burnout temperatures for different biomasses, in which the burning temperatures are approximately 300 °C to 500 °C. Studies have shown that LMW and MMW PAHs are likely to be emitted at low temperatures (<500 °C) [85].

4. Factors That Influence PAH Emissions

4.1. Types and Compositions of Biomass

Table 8 compares the PAHs emitted from the burning of various types of biomass, which shows that the burning of different types under the same conditions leads to different PAH EFs. For example, the PAH EFs of wheat straw (65.2 mg/kg) burning in brick cook stoves were approximately three times lower than those of corn straw (19.0 mg/kg) [90]. Dung cakes in open burning have a higher total PAH EF value than charcoal (53.8 mg/kg and 27.3 mg/kg, respectively) [91]. Based on the previously described PAH formation during biomass burning, biomass composition, such as volatile and nonvolatile components and moisture can influence the reaction conditions and progress, thus changing the concentration and composition of PAHs emissions. The chemical composition of biomass varies with biomass type [92]. Briefly, the emission characteristics of PAHs are mainly affected by volatile matter, nonvolatile matter, potassium salts, moisture and density of the biomass.

4.1.1. Volatile Matter

Biomass with high volatile contents can generate abundant phenyl radicals during burning, leading to massive PM-bound PAH emissions (Table 9). The PAH EFs of the same biomass burned in the same conditions increase with increasing volatile matter. Based on this feature, the emission of PAHs can be effectively reduced by pretreatments (briquettes or carbonization) that reduce the volatile content of the biomass. For example, Lea-Langton et al. reported that the higher volatile content of firewood (82.6%) than of charcoal (16%) leads to higher PAH emissions (73.4 ng/m3 and 7.9 ng/m3, respectively) [95]. Moreover, Sun et al. reported that the PAH emissions from burning carbonized maize and wheat were approximately 85% and 88% lower than those from burning unpretreated biomass fuel, respectively [96]. The significant decrease might be due to the briquette and carbonization pyrolyzing and volatilizing more than 80% of the volatile matter in biomass, which decreases the formation of phenyl radicals and PAHs during burning [97,98]. In addition, after discharge into the atmosphere, weather conditions will change the concentration of PAHs [99]. Studies have shown that temperature, ozone, pressure, and relative humidity constituted 43–70% of variability in PAH concentrations [100]. The concentration of PAHs increases with decreasing temperature and decreases with increasing humidity and pressure. The higher ozone concentration can increase the concentration of LMW and MMW PAHs but decrease that of HMW PAHs. Compared with ozone oxidation, LMW and MMW PAHs are more susceptible to photo-oxidation and thermal decomposition [100].

4.1.2. Nonvolatile Matter

In addition to volatile components, nonvolatile components in biomass are essential carbon sources for PAH formation. The pyrolysis of structural materials (such as cellulose and lignin) is the main formation process for PAHs during biomass burning [102,103]. Studies have shown that an increase of 200 mg to 500 mg in cellulose content can cause an increase of 14 μg/g to 24 μg/g in EFs of PAHs during burning [104]. Moreover, the burning of biomass with a high polyunsaturated fatty acid to saturated fatty acid (PUFA/SFA) ratio can lead to high PAH emissions [105,106]. This is because PUFAs have more carbon–carbon double bonds than SFAs, making it easier for them to form free radicals during pyrolysis and, therefore, promoting the generation of PAHs [107].

4.1.3. Potassium Salts

Potassium salts in biomass are considered to play a role in the formation of PAHs during biomass burning. Studies have shown that compared with rice straw containing low potassium (0.57 g/kg), wheat straw with high potassium content (31.3 g/kg) increases PAH emissions from burning by approximately three-fold (0.362 mg/g OC and 1.2 mg/g OC, respectively) [108]. During burning, inorganic potassium salts act as catalysts during the pyrolysis of lignin, which accelerates the pyrolysis of lignin into phenyl radicals and then forms PAHs through pyrosynthesis [108,109]. This finding indicates that biomass containing pyrolysis-promoting components tends to discharge more PAHs and highly toxic PAHs during burning. Therefore, the improvement and optimization of biomass is crucial to controlling PAH pollution caused by biomass burning.
To reduce the pyrolysis-promoting components in biomass, one possible solution is to wash the biomass with deionized water. Deionized water has been reported to extract minerals such as potassium, terpenoids and phenolic compounds from biomass, thus reducing the emission of PAHs during burning by approximately 60% [110]. A report showed that the PAH emission (1570 μg/kgdw) from the burning of raw fir was much higher than that (560 μg/kgdw) from the burning of fir washed with deionized water. In addition, washing with deionized water can change the composition of the discharged PAHs, which emit fewer HMW PAHs (five-ring) but higher LMW and MMW PAHs. For instance, after washing with deionized water, the proportion of LWM and MMW PAHs to the total PAHs increased from 88% (raw fir) to 99% (washed fir), causing toxic potency of emitted PAHs decreased by approximately 96% [110]. The results indicate that inorganic potassium salts can catalyze the pyrolysis, and washing the biomass with deionized water before burning can significantly lower the associated health risks to humans.

4.1.4. Moisture

Table 10 summarizes the changes in the concentration and composition of PAHs emitted from burning caused by changing the moisture content of biomass. Most of the results show an increase in the EFs of PAHs with increasing biomass moisture. As previously described, dehydration at the beginning of biomass burning leads to an oxygen-deficient atmosphere [111]. Guerrero F. et al. proved that an increase in biomass moisture content from 0% to 25% results in more CO being formed (maximum peaks of 2007 ppm and 3742 ppm, respectively) than CO2 [112]. These changes in burning conditions can cause incomplete oxidation of biomass, leading to the massive generation of PAHs during subsequent devolatilization and char burning. However, the results of Korenaga et al. (Table 10) showed that as the biomass moisture increased, the EFs of PAHs first decreased and then increased. This trend might imply that the dehydration step in the burning process is skipped during the burning of biomass containing no moisture, leading to an insufficient oxygen supply in a closed draft chamber. The insufficient oxygen supply leads to incomplete combustion of biomass, thus increasing the generation and emission of PAHs [93,113,114]. Moreover, the study showed that a lower biomass moisture content could increase the temperature in burning (maximum peaks of 537 °C and 236 °C for 0% and 25% moisture contents, respectively), which caused higher PAH formation [112,115].

4.1.5. Density of Biomass

In addition to the biomass components mentioned above, the density of biomass also affects the burning efficiency and PAH emissions [54]. At present, the pelletizing and briquetting of biomass has become an effective method for increasing the density of biomass [118]. The processes of pelletization and briquetting of biomass fuel are similar and include crushing, drying and pelletizing [119]. These processes can increase the biomass density, leading to a reduction in the burning rates to inhibit the incomplete combustion of biomass [120]. Moreover, the pelletizing and briquetting of biomass can decrease the contents of moisture and volatile matter, which further reduces PAH emissions [121]. The use of pelletized biomass has been reported to reduce total PAH emissions by approximately 89% (in the range of 69% to 94%) and to reduce emissions of toxic benzo[a]pyrene by approximately 89% (in the range of 60% to 94%) [122]. These measures can effectively decrease the health risks of biomass burning to humans.

4.2. Burning Conditions

Table 11 summarizes the EFs of PAHs emitted from biomass burning with different types of stoves. The burner is an exogenous factor that affects burning conditions (such as temperature and oxygen supply) and PAH emissions during biomass burning. Traditional domestic heating and cooking stoves (such as fireplaces, woodstoves, and brick stoves) normally have low burning efficiency and emit high PAHs during burning [123]. For example, the heating stove called Heated Kang is widely used in China. The structure of Heated Kang is a burning chamber (Kang) connected to a chimney by a tube, and there is no secondary air system to supply oxygen (or heated oxygen) to the burning chamber during burning [108]. Insufficient ventilation usually reduces the burning efficiency of biomass and increases the emission of PAHs and their adverse effects on human health [124,125,126]. Compared with traditional domestic stoves, improved stoves (such as pellet stoves and gasifier stoves) can decrease incomplete combustion due to the advanced ventilation system and stove temperature control system [127].

4.2.1. Burning Temperature

The burning temperature of the stove strongly affects the composition of the PAHs that form. For instance, Table 12 summarizes the increased rate of PAHs emissions by the same stove with the same oxygen supply at different temperatures relative to the PAHs emitted at 200 °C [131]. The results from laboratory simulations showed that the LMW and MMW PAHs begin to be emitted in great quantities during biomass burning with temperatures higher than or equal to 400 °C, and HMW PAHs start to form mainly at higher temperatures (≥ 500 °C) [104,132]. In addition, the emission of PAHs increases with increasing temperature in a specific range, and a higher temperature helps to better synthesize PAHs from fragments that are pyrolyzed from biomass fuel during burning [81].

4.2.2. Oxygen Supply

At a constant temperature, adjusting the oxygen supply can increase the air–fuel ratio in the stove to suppress incomplete combustion and reduce PAH emissions. Increasing the airflow is a commonly used way of improving the oxygen supply. Vicente et al. compared the PAHs emitted from biomass burning in fireplaces and woodstoves by burning the same biomass with the same amount of biomass [133]. In contrast to the fireplace, the woodstove added an extra ventilation pipe to draw fresh air, thereby increasing the air–fuel ratio to reduce incomplete combustion and PAH emissions [124,125]. As a result, burning in the fireplace led to a higher PAH concentration (92.0 ng/m3) than burning in the woodstove (8.82 ng/m3) [126]. The results from another study also confirmed that biomass burning in a fireplace resulted in higher PAH emissions (80.6 ng/m3) than burning in a woodstove (69.1 ng/m3) [134]. These findings highlight the positive role of optimizing the oxygen supply efficiency of stoves in reducing both PAH emissions from biomass burning and the associated health risks to humans. However, a rapid increase in the airflow in stoves during burning in actual use may decrease the air–fuel ratio and increase PAH emissions. Wei et al. compared the PAHs emitted from biomass burning in two similar stoves with different stove ages (1 year versus 15 years) [135]. Compared with the 1-year-old stove, the 15-year-old stove had a worse flue block, which reduced the oxygen supply and burning temperature. However, the measured PAH EF of the 1-year-old stove (330 mg/kg) was significantly higher than that of the 15-year-old stove (190 mg/kg). This result suggests that an abundant oxygen supply can accelerate biomass burning, but a surge may lead to rapid burning (i.e., incomplete combustion). Nevertheless, biomass can be converted into gaseous organic molecules such as methane and acetylene by heating it in the absence of oxygen prior to combustion [136,137]. This treatment can effectively improve the combustion efficiency of gaseous organic molecules compared to burning biomass directly, thereby reducing PAHs emissions and producing valuable materials such as graphene [138]. In addition, using supercritical water as an oxidant during biomass gasification can generate hydrogen and carbon monoxide, and reduce the emission of PAHs during combustion [139,140,141]. Therefore, the dual control of the oxygen supply and rate of the burner is considered to reduce the emission of PAHs from biomass burning and the related health risks.

4.2.3. Stove Designs

Based on the effect of temperature and oxygen supply during biomass burning on PAHs emissions, the designs of stoves become a critical factor. An improper stove design can lead to low thermal performance and high emission of air pollutants [142]. A report shows that the space size and the fuel load of the stove can affect the PAHs emission [143]. Less free space in the stove and high loaded fuel cause the temperature in the stove to rise rapidly during biomass burning (flue gas temperature was 143 °C and 187 °C for partial load and full load, respectively), which produces more HMW PAH than burning at low temperatures. Moreover, a substandard airflow path can cause insufficient mixing of oxygen with fuel. Szramowiat-Sala K. et al. compares PAH EFs from burning the same biomass in the same stove with different airflow paths [144]. The EFs of PAHs from burning biomass in the stove with the better airflow path (air inlet located below the door, above the doors and at the rear wall of the stove; EFs = 2.20 mg/kg) was significantly lower than those in the stove with a worse airflow path (air inlets located only below the doors and above the doors; EFs = 10.0 g/kg).

5. Conclusions

This review summarizes the related research on PAH emissions from biomass combustion and discusses the effects of biomass composition and combustion conditions on PAH emissions based on the formation mechanism and emission characteristics of PAHs.
Biomass with high volatile matter content can increase the formation of phenyl radicals that increase the PAH emissions. The high cellulose content and PUFA/SFA ratio of biomass increase the forms of free radicals that enhance PAH EFs. Potassium salts in biomass can act as catalysts for PAH formation. Burning of biomass with a high moisture content causes oxygen deficiency during combustion, which increases PAH formation and leads to a higher health risk. Increasing the biomass density can reduce the biomass burning rates and decrease incomplete combustion leading to low PAH emissions. High burning temperatures can increase the formation of HMW PAHs, causing severe health effects to humans, and optimizing the oxygen supply efficiency of stoves can significantly decrease PAH formation during burning.
To control the incomplete combustion of biomass and the emissions of PAHs, we recommend washing the biomass with deionized water and pelletizing, briquetting or carbonizing the biomass after drying the washed biomass. Furthermore, the domestic stove burning temperature should be controlled at a relatively low degree (<500 °C), and the oxygen supply should be regulated without a rapid increase in the airflow.

Author Contributions

Conceptualization, methodology, H.Z., L.Z. and N.T.; investigation, formal analysis, writing—original draft preparation, H.Z.; writing—review and editing, supervision, funding acquisition L.Z. and N.T.; validation, X.Z., Y.W., P.B. and K.H. All authors have read and agreed to the published version of the manuscript.

Funding

This work was supported by the Environment Research and Technology Development Fund (5–1951) of the Environmental Restoration and Conservation Agency of Japan; the Bilateral Open Partnership Joint Research Projects of the Japan Society for the Promotion of Science, Japan (JPJSBP120219914); Project for Outstanding Next Generation Ph.D. Students, Kanazawa University, Japan (2022); the CHOZEN Project of Kanazawa University, Japan (2019); and the cooperative research programs of Institute of Nature and Environmental Technology, Kanazawa University, Japan (2020).

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Data sharing not applicable.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Tang, N.; Hattori, T.; Taga, R.; Igarashi, K.; Yang, X.Y.; Tamura, K.; Kakimoto, H.; Mishukov, V.F.; Toriba, A.; Kizu, R.; et al. Polycyclic aromatic hydrocarbons and nitro polycyclic aromatic hydrocarbons in urban air particulates and their relationship to emission sources in the Pan–Japan Sea countries. Atmos. Environ. 2005, 39, 5817–5826. [Google Scholar] [CrossRef]
  2. Zhang, L.L.; Yang, L.; Zhou, Q.Y.; Zhang, X.; Xing, W.L.; Wei, Y.J.; Hu, M.; Zhao, L.X.; Toriba, A.; Hayakawa, K.; et al. Size distribution of particulate polycyclic aromatic hydrocarbons in fresh combustion smoke and ambient air: A review. J. Environ. Sci. 2020, 88, 370–384. [Google Scholar] [CrossRef] [PubMed]
  3. Yang, L.; Zhang, X.; Xing, W.L.; Zhou, Q.Y.; Zhang, L.L.; Wu, Q.; Zhou, Z.J.; Chen, R.J.; Toriba, A.; Hayakawa, K.; et al. Yearly variation in characteristics and health risk of polycyclic aromatic hydrocarbons and nitro-PAHs in urban shanghai from 2010–2018. J. Environ. Sci. 2021, 99, 72–79. [Google Scholar] [CrossRef] [PubMed]
  4. Hayakawa, K. Environmental Behaviors and Toxicities of Polycyclic Aromatic Hydrocarbons and Nitropolycyclic Aromatic Hydrocarbons. Chem. Pharm. Bull. 2016, 64, 83–94. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  5. Zhang, L.L.; Morisaki, H.; Wei, Y.J.; Li, Z.G.; Yang, L.; Zhou, Q.Y.; Zhang, X.; Xing, W.L.; Hu, M.; Shima, M.; et al. PM2.5-bound polycyclic aromatic hydrocarbons and nitro-polycyclic aromatic hydrocarbons inside and outside a primary school classroom in Beijing: Concentration, composition, and inhalation cancer risk. Sci. Total Environ. 2020, 705, 135840. [Google Scholar] [CrossRef] [PubMed]
  6. Zhang, L.L.; Tokuda, T.; Yang, L.; Zhou, Q.Y.; Zhang, X.; Xing, W.L.; Wu, Q.; Zhou, Z.J.; Chen, R.J.; Kameda, T.; et al. Characteristics and health risks of particulate polycyclic aromatic hydrocarbons and nitro-polycyclic aromatic hydrocarbons at urban and suburban elementary schools in Shanghai, China. Asian J. Atmos. Environ. 2019, 13, 266–275. [Google Scholar] [CrossRef]
  7. Zhang, L.L.; Morisaki, H.; Wei, Y.J.; Li, Z.G.; Yang, L.; Zhou, Q.Y.; Zhang, X.; Xing, W.L.; Hu, M.; Shima, M.; et al. Characteristics of air pollutants inside and outside a primary school classroom in Beijing and respiratory health impact on children. Environ. Pollut. 2019, 255, 113147. [Google Scholar] [CrossRef]
  8. Yang, L.; Zhang, H.; Zhang, X.; Xing, W.L.; Wang, Y.; Bai, P.C.; Zhang, L.L.; Hayakawa, K.; Toriba, A.; Tang, N. Exposure to atmospheric particulate matter-bound polycyclic aromatic hydrocarbons and their health effects: A review. Int. J. Environ. Res. Public Health 2021, 18, 2177. [Google Scholar] [CrossRef]
  9. Zhang, H.; Yang, L.; Zhang, X.; Xing, W.L.; Wang, Y.; Bai, P.C.; Zhang, L.L.; Li, Y.; Hayakawa, K.; Toriba, A.; et al. Characteristics and health risks of polycyclic aromatic hydrocarbons and nitro-PAHs in Xinxiang, China in 2015 and 2017. Int. J. Environ. Res. Public Health 2021, 18, 3017. [Google Scholar] [CrossRef]
  10. Xu, Y.; Cui, G.M. Influence of spectral characteristics of the Earth’s surface radiation on the greenhouse effect: Principles and mechanisms. Atmos. Environ. 2021, 244, 117908. [Google Scholar] [CrossRef]
  11. Zhang, X.; Zhang, L.L.; Yang, L.; Zhou, Q.Y.; Xing, W.L.; Toriba, A.; Hayakawa, K.; Wei, Y.J.; Tang, N. Characteristics of polycyclic aromatic hydrocarbons (PAHs) and common air pollutants at Wajima, a remote background site in Japan. Int. J. Environ. Res. Public Health 2020, 17, 957. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  12. Xing, W.L.; Zhang, L.L.; Yang, L.; Zhou, Q.Y.; Zhang, X.; Toriba, A.; Hayakawa, K.; Tang, N. Characteristics of PM2.5-bound polycyclic aromatic hydrocarbons and nitro-polycyclic aromatic hydrocarbons at a roadside air pollution monitoring station in Kanazawa, Japan. Int. J. Environ. Res. Public Health 2020, 17, 805. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  13. Bilgili, F.; Koçak, E.; Bulut, Ü.; Kuşkaya, S. Can biomass energy be an efficient policy tool for sustainable development. Renew. Sustain. Energy Rev. 2017, 71, 830–845. [Google Scholar] [CrossRef]
  14. World Energy Outlook 2019. Available online: https://www.iea.org/reports/world-energy-outlook-2019 (accessed on 22 January 2022).
  15. Li, M.Q. Peak oil, the rise of China and India, and the global energy crisis. J. Contemp. Asia 2007, 37, 449–471. [Google Scholar] [CrossRef]
  16. Bang, G. Energy security and climate change concerns: Triggers for energy policy change in the United States? Energy Policy 2010, 38, 1645–1653. [Google Scholar] [CrossRef]
  17. Saboori, B.; Sulaiman, J. Environmental degradation, economic growth and energy consumption: Evidence of the environmental Kuznets curve in Malaysia. Energy Policy 2013, 60, 892–905. [Google Scholar] [CrossRef]
  18. Vasylieva, T.; Lyulyov, O.; Bilan, Y.; Streimikiene, D. Sustainable Economic Development and Greenhouse Gas Emissions: The Dynamic Impact of Renewable Energy Consumption, GDP, and Corruption. Energies 2019, 12, 3289. [Google Scholar] [CrossRef] [Green Version]
  19. Górecki, J.; Płoszaj, E. Cost risk of construction of small hydroelectric power plants. MATEC Web Conf. 2019, 262, 07004. [Google Scholar] [CrossRef]
  20. Prăvălie, R.; Bandoc, G. Nuclear energy: Between global electricity demand, worldwide decarbonisation imperativeness, and planetary environmental implications. J. Environ. Manag. 2018, 209, 81–92. [Google Scholar] [CrossRef]
  21. Irfan, M.; Zhao, Z.Y.; Panjwani, M.; Mangi, F.; Li, H.; Jan, A.; Ahmad, M.; Rehman, A. Assessing the energy dynamics of Pakistan: Prospects of biomass energy. Energy Rep. 2020, 6, 80–93. [Google Scholar] [CrossRef]
  22. Kumar, A.; Kumar, N.; Baredar, P.; Shukla, A. A review on biomass energy resources, potential, conversion and policy in India. Renew. Sustain. Energy Rev. 2015, 45, 530–539. [Google Scholar] [CrossRef]
  23. The Energy Progress Report 2020. Available online: https://trackingsdg7.esmap.org/data/files/download-documents/03-sdg7-chapter2-accesstocleanfuelsandtech4cooking.pdf (accessed on 23 January 2022).
  24. Bhattacharya, S. Biomass energy in Asia: A review of status, technologies and policies in Asia. Energy Sustain. Dev. 2002, 6, 5–10. [Google Scholar] [CrossRef]
  25. Hansen, T.; Hansen, U. How many firms benefit from a window of opportunity? Knowledge spillovers, industry characteristics, and catching up in the Chinese biomass power plant industry. Ind. Corp. Chang. 2020, 29, 1211–1232. [Google Scholar] [CrossRef]
  26. Sarigiannis, D.; Karakitsios, S.; Zikopoulos, D.; Nikolaki, S.; Kermenidou, M. Lung cancer risk from PAHs emitted from biomass combustion. Environ. Res. 2015, 137, 147–156. [Google Scholar] [CrossRef]
  27. Clark, M.; Peel, J.; Burch, J.; Nelson, T.; Robinson, M.; Conway, S.; Bachand, A.; Reynolds, S. Impact of improved cookstoves on indoor air pollution and adverse health effects among Honduran women. Int. J. Environ. Health Res. 2009, 19, 357–368. [Google Scholar] [CrossRef]
  28. Lal, K.; Mani, U.; Pandey, R.; Singh, N.; Singh, A.; Patel, D.; Singh, M.; Murthy, R. Multiple approaches to evaluate the toxicity of the biomass fuel cow dung (Kanda) smoke. Ecotoxicol. Environ. Saf. 2011, 74, 2126–2132. [Google Scholar] [CrossRef]
  29. Zhang, L.L.; Yang, L.; Bi, J.R.; Liu, Y.Z.; Toriba, A.; Hayakawa, K.; Nagao, S.; Tang, N. Characteristics and unique sources of polycyclic aromatic hydrocarbons and nitro-polycyclic aromatic hydrocarbons in PM2.5 at a highland background site in northwestern China. Environ. Pollut. 2021, 274, 116527. [Google Scholar] [CrossRef]
  30. Vicente, E.; Alves, C. An overview of particulate emissions from residential biomass combustion. Atmos. Res. 2018, 199, 159–185. [Google Scholar] [CrossRef]
  31. Stich, J.; Ramachandran, S.; Hamacher, T.; Stimming, U. Techno-economic estimation of the power generation potential from biomass residues in Southeast Asia. Energy 2017, 135, 930–942. [Google Scholar] [CrossRef]
  32. Lemieux, P.; Lutes, C.; Santoianni, D. Emissions of organic air toxics from open burning: A comprehensive review. Prog. Energy Combust. Sci. 2004, 30, 1–32. [Google Scholar] [CrossRef]
  33. Yang, L.; Suzuki, G.; Zhang, L.L.; Zhou, Q.Y.; Zhang, X.; Xing, W.L.; Shima, M.; Yoda, Y.; Nakatsubo, R.; Hiraki, T.; et al. The characteristics of polycyclic aromatic hydrocarbons in different emission source areas in Shenyang, China. Int. J. Environ. Res. Public Health 2019, 16, 2817. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  34. Yang, L.; Zhou, Q.Y.; Zhang, H.; Zhang, X.; Xing, W.L.; Wang, Y.; Bai, P.C.; Yamauchi, M.; Chohji, T.; Zhang, L.L.; et al. Atmospheric Behaviour of Polycyclic and Nitro-Polycyclic Aromatic Hydrocarbons and Water-Soluble Inorganic Ions in Winter in Kirishima, a Typical Japanese Commercial City. Int. J. Environ. Res. Public Health 2021, 18, 688. [Google Scholar] [CrossRef] [PubMed]
  35. Shen, H.Z.; Huang, Y.; Wang, R.; Zhu, D.; Li, W.; Shen, G.F.; Wang, B.; Zhang, Y.Y.; Cheng, Y.C.; Lu, Y.; et al. Global Atmospheric Emissions of Polycyclic Aromatic Hydrocarbons from 1960 to 2008 and Future Predictions. Environ. Sci. Technol. 2013, 47, 6415–6424. [Google Scholar] [CrossRef] [Green Version]
  36. Zhang, Y.X.; Tao, S. Global atmospheric emission inventory of polycyclic aromatic hydrocarbons (PAHs) for 2004. Atmos. Environ. 2009, 43, 812–819. [Google Scholar] [CrossRef]
  37. Chen, L.; Moosmüller, H.; Arnott, W.; Chow, J.; Watson, J.; Susott, R.; Babbitt, R.; Wold, C.; Lincoln, E.; Hao, W.M. Emissions from Laboratory Combustion of Wildland Fuels: Emission Factors and Source Profiles. Environ. Sci. Technol. 2007, 41, 4317–4325. [Google Scholar] [CrossRef]
  38. World Meteorological Organization. 2019. Available online: https://public.wmo.int/en/media/news/july-matched-and-maybe-broke-record-hottest-month-analysis-began (accessed on 21 January 2022).
  39. Touma, D.; Stevenson, S.; Lehner, F.; Coats, S. Human-driven greenhouse gas and aerosol emissions cause distinct regional impacts on extreme fire weather. Nat. Commun. 2021, 12, 212. [Google Scholar] [CrossRef]
  40. Kim Oanh, N.; Albina, D.; Ping, L.; Wang, X.K. Emission of particulate matter and polycyclic aromatic hydrocarbons from select cookstove–fuel systems in Asia. Biomass Bioenergy 2005, 28, 579–590. [Google Scholar] [CrossRef]
  41. Yang, H.H.; Tsai, C.H.; Chao, M.R.; Su, Y.L.; Chien, S.M. Source identification and size distribution of atmospheric polycyclic aromatic hydrocarbons during rice straw burning period. Atmos. Environ. 2006, 40, 1266–1274. [Google Scholar] [CrossRef]
  42. Yang, L.; Zhang, L.L.; Chen, L.J.; Han, C.; Akutagawa, T.; Endo, O.; Yamauchi, M.; Neroda, A.; Toriba, A.; Tang, N. Polycyclic aromatic hydrocarbons and nitro-polycyclic aromatic hydrocarbons in five East Asian cities: Seasonal characteristics, health risks, and yearly variations. Environ. Pollut. 2021, 287, 117360. [Google Scholar] [CrossRef]
  43. Křůmal, K.; Mikuška, P.; Horák, J.; Hopan, F.; Krpec, K. Comparison of emissions of gaseous and particulate pollutants from the combustion of biomass and coal in modern and old-type boilers used for residential heating in the Czech Republic, Central Europe. Chemosphere 2019, 229, 51–59. [Google Scholar] [CrossRef]
  44. Yang, X.Y.; Liu, S.J.; Xu, Y.S.; Liu, Y.; Chen, L.J.; Tang, N.; Hayakawa, K. Emission factors of polycyclic and nitro-polycyclic aromatic hydrocarbons from residential combustion of coal and crop residue pellets. Environ. Pollut. 2017, 231, 1265–1273. [Google Scholar] [CrossRef] [PubMed]
  45. Lewis, J.; Hollingsworth, J.; Chartier, R.; Cooper, E.; Foster, W.; Gomes, G.; Kussin, P.; MacInnis, J.; Padhi, B.; Panigrahi, P.; et al. Biogas Stoves Reduce Firewood Use, Household Air Pollution, and Hospital Visits in Odisha, India. Environ. Sci. Technol. 2016, 51, 560–569. [Google Scholar] [CrossRef] [PubMed]
  46. Fleming, L.; Lin, P.; Roberts, J.; Selimovic, V.; Yokelson, R.; Laskin, J.; Laskin, A.; Nizkorodov, S. Molecular composition and photochemical lifetimes of brown carbon chromophores in biomass burning organic aerosol. Atmos. Chem. Phys. 2020, 20, 1105–1129. [Google Scholar] [CrossRef] [Green Version]
  47. Nolte, C.; Schauer, J.; Cass, G.; Simoneit, B. Highly Polar Organic Compounds Present in Wood Smoke and in the Ambient Atmosphere. Environ. Sci. Technol. 2001, 35, 1912–1919. [Google Scholar] [CrossRef] [PubMed]
  48. Orakij, W.; Chetiyanukornkul, T.; Kasahara, C.; Boongla, Y.; Chuesaard, T.; Furuuchi, M.; Hata, M.; Tang, N.; Hayakawa, K.; Toriba, A. Polycyclic aromatic hydrocarbons and their nitro derivatives from indoor biomass-fueled cooking in two rural areas of Thailand: A case study. Air Qual. Atmos. Health 2017, 10, 747–761. [Google Scholar] [CrossRef]
  49. Chiu, J.C.; Shen, Y.H.; Li, H.W.; Chang, S.S.; Wang, L.C.; Chang-Chien, G.P. Effect of biomass open burning on particulate matter and polycyclic aromatic hydrocarbon concentration levels and PAH dry deposition in ambient air. J. Environ. Sci. Health Part A 2011, 46, 188–197. [Google Scholar] [CrossRef] [PubMed]
  50. Gerde, P.; Medinsky, M.; Bond, J. Particle-associated polycyclic aromatic hydrocarbons—A reappraisal of their possible role in pulmonary carcinogenesis. Toxicol. Appl. Pharmacol. 1991, 108, 1–13. [Google Scholar] [CrossRef]
  51. Ekici, A.; Ekici, M.; Kurtipek, E.; Akin, A.; Arslan, M.; Kara, T.; Apaydin, Z.; Demir, S. Obstructive airway diseases in women exposed to biomass smoke. Environ. Res. 2005, 99, 93–98. [Google Scholar] [CrossRef]
  52. Puttaswamy, N.; Saidam, S.; Sivasamy, S.; Rajendran, G.; Balakrishnan, K.; Smith, S. Personal exposures to polycyclic aromatic hydrocarbons and biological monitoring among rural women cooking with different fuels in India. Environ. Epidemiol. 2019, 3, 318–319. [Google Scholar] [CrossRef]
  53. Pham, C.; Boongla, Y.; Nghiem, T.; Le, H.; Tang, N.; Toriba, A.; Hayakawa, K. Emission Characteristics of Polycyclic Aromatic Hydrocarbons and Nitro-Polycyclic Aromatic Hydrocarbons from Open Burning of Rice Straw in the North of Vietnam. Int. J. Environ. Res. Public Health 2019, 16, 2343. [Google Scholar] [CrossRef] [Green Version]
  54. Zhang, Y.; Shen, Z.X.; Sun, J.; Zhang, L.M.; Zhang, B.; Zou, H.J.; Zhang, T.; Ho, S.H.; Chang, X.J.; Xu, H.M.; et al. Parent, alkylated, oxygenated and nitrated polycyclic aromatic hydrocarbons in PM2.5 emitted from residential biomass burning and coal combustion: A novel database of 14 heating scenarios. Environ. Pollut. 2021, 268, 115881. [Google Scholar] [CrossRef] [PubMed]
  55. Emil, V. Fate of Fuel-Bound Nitrogen and Sulfur in Biomass-Fired Industrial Boilers. Ph.D. Thesis, Åbo Akademi University, Turku, Finland, 2014. [Google Scholar]
  56. Zając, G.; Szyszlak-Bargłowicz, J.; Szczepanik, M. Influence of Biomass Incineration Temperature on the Content of Selected Heavy Metals in the Ash Used for Fertilizing Purposes. Appl. Sci. 2019, 9, 1790. [Google Scholar] [CrossRef] [Green Version]
  57. Saastamoinen, J.; Richard, J. Drying, Pyrolysis and Combustion of Biomass Particles. In Research in Thermochemical Biomass Conversion, 1st ed.; Bridgwater, A.V., Kuester, J.L., Eds.; Springer: Dordrecht, The Netherlands, 1988; Volume 1, p. 1194. [Google Scholar]
  58. Chao, C.; Kwong, P.; Wang, J.; Cheung, C.; Kendall, G. Co-firing coal with rice husk and bamboo and the impact on particulate matters and associated polycyclic aromatic hydrocarbon emissions. Bioresour. Technol. 2008, 99, 83–93. [Google Scholar] [CrossRef] [PubMed]
  59. Dhahak, A.; Bounaceur, R.; Le Dreff-Lorimier, C.; Schmidt, G.; Trouve, G.; Battin-Leclerc, F. Development of a detailed kinetic model for the combustion of biomass. Fuel 2019, 242, 756–774. [Google Scholar] [CrossRef] [Green Version]
  60. Mastral, A.; Callén, M. A Review on Polycyclic Aromatic Hydrocarbon (PAH) Emissions from Energy Generation. Environ. Sci. Technol. 2000, 34, 3051–3057. [Google Scholar] [CrossRef]
  61. Demirbas, A. Effect of Temperature on Pyrolysis Products from Biomass. Energy Sources Part A 2007, 29, 329–336. [Google Scholar] [CrossRef]
  62. Wang, C.Y.; Wang, Y.D.; Herath, H. Polycyclic aromatic hydrocarbons (PAHs) in biochar—Their formation, occurrence and analysis: A review. Org. Geochem. 2017, 114, 1–11. [Google Scholar] [CrossRef]
  63. Hussar, E.; Richards, S.; Lin, Z.; Dixon, R.; Johnson, K. Human Health Risk Assessment of 16 Priority Polycyclic Aromatic Hydrocarbons in Soils of Chattanooga, Tennessee, USA. Water Air Soil Pollut. 2012, 223, 5535–5548. [Google Scholar] [CrossRef]
  64. Wang, W.; Ding, X.; Turap, Y.; Tursun, Y.; Abulizi, A.; Wang, X.M.; Shao, L.Y.; Talifu, D.; An, J.Q.; Zhang, X.X.; et al. Distribution, sources, risks, and vitro DNA oxidative damage of PM2.5-bound atmospheric polycyclic aromatic hydrocarbons in Urumqi, NW China. Sci. Total Environ. 2020, 739, 139518. [Google Scholar] [CrossRef]
  65. Forsey, S.; Thomson, N.; Barker, J. Oxidation kinetics of polycyclic aromatic hydrocarbons by permanganate. Chemosphere 2010, 79, 628–636. [Google Scholar] [CrossRef]
  66. Dejchanchaiwong, R.; Tekasakul, P.; Tekasakul, S.; Phairuang, W.; Nim, N.; Sresawasd, C.; Thongboon, K.; Thongyen, T.; Suwattiga, P. Impact of transport of fine and ultrafine particles from open biomass burning on air quality during 2019 Bangkok haze episode. J. Environ. Sci. 2020, 97, 149–161. [Google Scholar] [CrossRef] [PubMed]
  67. Tipayarom, A.; Kim Oanh, N. Influence of rice straw open burning on levels and profiles of semi-volatile organic compounds in ambient air. Chemosphere 2020, 243, 125379. [Google Scholar] [CrossRef] [PubMed]
  68. Urbanski, S. Combustion efficiency and emission factors for wildfire-season fires in mixed conifer forests of the northern Rocky Mountains, US. Atmos. Chem. Phys. 2013, 13, 7241–7262. [Google Scholar] [CrossRef] [Green Version]
  69. Kim Oanh, N.; Permadi, D.; Hopke, P.; Smith, K.; Dong, N.; Dang, A. Annual emissions of air toxics emitted from crop residue open burning in Southeast Asia over the period of 2010–2015. Atmos. Environ. 2018, 187, 163–173. [Google Scholar] [CrossRef]
  70. Schuster, J.; Harner, T.; Su, K.; Eng, A.; Wnorowski, A.; Charland, J. Temporal and Spatial Trends of Polycyclic Aromatic Compounds in Air across the Athabasca Oil Sands Region Reflect Inputs from Open Pit Mining and Forest Fires. Environ. Sci. Technol. Lett. 2019, 6, 178–183. [Google Scholar] [CrossRef] [Green Version]
  71. Wentworth, G.; Aklilu, Y.; Landis, M.; Hsu, Y. Impacts of a large boreal wildfire on ground level atmospheric concentrations of PAHs, VOCs and ozone. Atmos. Environ. 2018, 178, 19–30. [Google Scholar] [CrossRef]
  72. Wang, X.Y.; Meyer, C.; Reisen, F.; Keywood, M.; Thai, P.; Hawker, D.; Powell, J.; Mueller, J. Emission Factors for Selected Semivolatile Organic Chemicals from Burning of Tropical Biomass Fuels and Estimation of Annual Australian Emissions. Environ. Sci. Technol. 2017, 51, 9644–9652. [Google Scholar] [CrossRef] [Green Version]
  73. Bhargava, A.; Khanna, R.; Bhargava, S.; Kumar, S. Exposure risk to carcinogenic PAHs in indoor-air during biomass combustion whilst cooking in rural India. Atmos. Environ. 2004, 38, 4761–4767. [Google Scholar] [CrossRef]
  74. Zhang, J.D.; Liu, W.J.; Xu, Y.S.; Cai, C.Y.; Liu, Y.; Tao, S.; Liu, W.X. Distribution characteristics of and personal exposure with polycyclic aromatic hydrocarbons and particulate matter in indoor and outdoor air of rural households in Northern China. Environ. Pollut. 2019, 255, 113176. [Google Scholar] [CrossRef]
  75. Wang, H.L.; Zhuang, Y.H.; Hao, Z.P.; Cao, M.Q.; Zhong, J.X.; Wang, X.K.; Nguyen, T. Polycyclic aromatic hydrocarbons from rural household biomass burning in a typical Chinese village. Sci. China Ser. D Earth Sci. 2008, 51, 1013–1020. [Google Scholar] [CrossRef]
  76. Ding, J.N.; Zhong, J.J.; Yang, Y.F.; Li, B.G.; Shen, G.F.; Su, Y.H.; Wang, C.; Li, W.; Shen, H.Z.; Wang, B.; et al. Occurrence and exposure to polycyclic aromatic hydrocarbons and their derivatives in a rural Chinese home through biomass fuelled cooking. Environ. Pollut. 2012, 169, 160–166. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  77. Perrino, C.; Tofful, L.; Torre, S.; Sargolini, T.; Canepari, S. Biomass burning contribution to PM10 concentration in Rome (Italy): Seasonal, daily and two-hourly variations. Chemosphere 2019, 222, 839–848. [Google Scholar] [CrossRef] [PubMed]
  78. Soleimanian, E.; Mousavi, A.; Taghvaee, S.; Sowlat, M.; Hasheminassab, S.; Polidori, A.; Sioutas, C. Spatial trends and sources of PM2.5 organic carbon volatility fractions (OCx) across the Los Angeles Basin. Atmos. Environ. 2019, 209, 201–211. [Google Scholar] [CrossRef]
  79. Jeong, C.; Evans, G.; Dann, T.; Graham, M.; Herod, D.; Dabek-Zlotorzynska, E.; Mathieu, D.; Ding, L.Y.; Wang, D. Influence of biomass burning on wintertime fine particulate matter: Source contribution at a valley site in rural British Columbia. Atmos. Environ. 2008, 42, 3684–3699. [Google Scholar] [CrossRef]
  80. Pehnec, G.; Jakovljević, I. Carcinogenic Potency of Airborne Polycyclic Aromatic Hydrocarbons in Relation to the Particle Fraction Size. Int. J. Environ. Res. Public Health 2018, 15, 2485. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  81. Kuskowska, K.; Rogula-Kozłowska, W. Seasonal variation in health exposure to PM-bound Polycyclic Aromatic Hydrocarbons in selected sport facility. MATEC Web Conf. 2018, 247, 00047. [Google Scholar] [CrossRef] [Green Version]
  82. Godec, R.; Jakovljević, I.; Šega, K.; Čačković, M.; Bešlić, I.; Davila, S.; Pehnec, G. Carbon species in PM10 particle fraction at different monitoring sites. Environ. Pollut. 2016, 216, 700–710. [Google Scholar] [CrossRef]
  83. Finardi, S.; Radice, P.; Cecinato, A.; Gariazzo, C.; Gherardi, M.; Romagnoli, P. Seasonal variation of PAHs concentration and source attribution through diagnostic ratios analysis. Urban Clim. 2017, 22, 19–34. [Google Scholar] [CrossRef]
  84. Schnelle-Kreis, J.; Sklorz, M.; Orasche, J.; Stölzel, M.; Peters, A.; Zimmermann, R. Semi Volatile Organic Compounds in Ambient PM2.5 Seasonal Trends and Daily Resolved Source Contributions. Environ. Sci. Technol. 2007, 41, 3821–3828. [Google Scholar] [CrossRef]
  85. Han, Y.; Chen, Y.J.; Feng, Y.L.; Song, W.H.; Cao, F.; Zhang, Y.L.; Li, Q.; Yang, X.; Chen, J.M. Different formation mechanisms of PAH during wood and coal combustion under different temperatures. Atmos. Environ. 2020, 222, 117084. [Google Scholar] [CrossRef]
  86. Li, Z.Y.; Wang, Y.T.; Li, Z.X.; Guo, S.T.; Hu, Y. Levels and Sources of PM2.5-associated PAHs during and after the Wheat Harvest in a Central Rural Area of the Beijing-Tianjin-Hebei (BTH) Region. Aerosol Air Qual. Res. 2020, 20, 1070–1082. [Google Scholar] [CrossRef] [Green Version]
  87. Parvez, A.; Wu, T. Characteristics and interactions between coal and carbonaceous wastes during co-combustion. J. Energy Inst. 2017, 90, 12–20. [Google Scholar] [CrossRef]
  88. Kumar, P.; Kumar Nandi, B. Combustion characteristics of high ash Indian coal, wheat straw, wheat husk and their blends. Mater. Sci. Energy Technol. 2021, 4, 274–281. [Google Scholar] [CrossRef]
  89. Li, L.N.; Ren, Q.Q.; Wang, X.; Li, S.Y.; Lu, Q.G. TG–MS analysis of thermal behavior and gaseous emissions during co-combustion of straw with municipal sewage sludge. J. Therm. Anal. Calorim. 2014, 118, 449–460. [Google Scholar] [CrossRef]
  90. Shen, G.F.; Wang, W.; Yang, Y.F.; Ding, J.N.; Xue, M.; Min, Y.J.; Zhu, C.; Shen, H.Z.; Li, W.; Wang, B.; et al. Emissions of PAHs from Indoor Crop Residue Burning in a Typical Rural Stove: Emission Factors, Size Distributions, and Gas−Particle Partitioning. Environ. Sci. Technol. 2011, 45, 1206–1212. [Google Scholar] [CrossRef] [Green Version]
  91. Verma, P.; Sah, D.; Dubey, J.; Kumari, K.; Lakhani, A. Mutagenic and Cancer Risk Estimation of Particulate Bound Polycyclic Aromatic Hydrocarbons from the Emission of Different Biomass Fuels. Chem. Res. Toxicol. 2021, 34, 743–753. [Google Scholar] [CrossRef]
  92. Wang, X.L.; Yang, Z.L.; Liu, X.; Huang, G.Q.; Xiao, W.H.; Han, L.J. The composition characteristics of different crop straw types and their multivariate analysis and comparison. Waste Manag. 2020, 110, 87–97. [Google Scholar] [CrossRef]
  93. Shen, G.F.; Tao, S.; Chen, Y.C.; Zhang, Y.Y.; Wei, S.Y.; Xue, M.; Wang, B.; Wang, R.; Lu, Y.; Li, W.; et al. Emission Characteristics for Polycyclic Aromatic Hydrocarbons from Solid Fuels Burned in Domestic Stoves in Rural China. Environ. Sci. Technol. 2013, 47, 14485–14494. [Google Scholar] [CrossRef]
  94. Hosseini, S.; Urbanski, S.; Dixit, P.; Qi, L.; Burling, I.; Yokelson, R.; Johnson, T.; Shrivastava, M.; Jung, H.; Weise, D.; et al. Laboratory characterization of PM emissions from combustion of wildland biomass fuels. J. Geophys. Res. Atmos. 2013, 118, 9914–9929. [Google Scholar] [CrossRef]
  95. Lea-Langton, A.; Spracklen, D.; Arnold, S.; Conibear, L.; Chan, J.; Mitchell, E.; Jones, J.; Williams, A. PAH emissions from an African cookstove. J. Energy Inst. 2019, 92, 587–593. [Google Scholar] [CrossRef]
  96. Sun, J.; Shen, Z.X.; Zhang, Y.; Zhang, Q.; Lei, Y.L.; Huang, Y.; Niu, X.Y.; Xu, H.M.; Cao, J.J.; Ho, S.; et al. Characterization of PM2.5 source profiles from typical biomass burning of maize straw, wheat straw, wood branch, and their processed products (briquette and charcoal) in China. Atmos. Environ. 2019, 205, 36–45. [Google Scholar] [CrossRef]
  97. Shen, Z.X.; Cao, J.J.; Liu, S.X.; Zhu, C.S.; Wang, X.; Zhang, T.; Xu, H.M.; Hu, T.F. Chemical Composition of PM10 and PM2.5 Collected at Ground Level and 100 Meters during a Strong Winter-Time Pollution Episode in Xi’an, China. J. Air Waste Manag. Assoc. 2011, 61, 1150–1159. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  98. Kim Oanh, N.; Bætz Reutergårdh, L.; Dung, N. Emission of Polycyclic Aromatic Hydrocarbons and Particulate Matter from Domestic Combustion of Selected Fuels. Environ. Sci. Technol. 1999, 33, 2703–2709. [Google Scholar] [CrossRef]
  99. Soleimanian, E.; Taghvaee, S.; Sioutas, C. Characterization of organic compounds and oxidative potential of aqueous PM2.5 suspensions collected via an aerosol-into-liquid collector for use in toxicology studies. Atmos. Environ. 2020, 241, 117839. [Google Scholar] [CrossRef]
  100. Pehnec, G.; Jakovljević, I.; Šišović, A.; Bešlić, I.; Vađić, V. Influence of ozone and meteorological parameters on levels of polycyclic aromatic hydrocarbons in the air. Atmos. Environ. 2016, 131, 263–268. [Google Scholar] [CrossRef]
  101. Li, Q.; Qi, J.; Jiang, J.K.; Wu, J.J.; Duan, L.; Wang, S.X.; Hao, J.M. Significant reduction in air pollutant emissions from household cooking stoves by replacing raw solid fuels with their carbonized products. Sci. Total Environ. 2019, 650, 653–660. [Google Scholar] [CrossRef]
  102. Růžičková, J.; Kucbel, M.; Raclavská, H.; Švédová, B.; Raclavský, K.; Juchelková, D. Comparison of organic compounds in char and soot from the combustion of biomass in boilers of various emission classes. J. Environ. Manag. 2019, 236, 769–783. [Google Scholar] [CrossRef]
  103. Yang, C.R.; Lin, T.C.; Chang, F.H. Particle size distribution and PAH concentrations of incense smoke in a combustion chamber. Environ. Pollut. 2007, 145, 606–615. [Google Scholar] [CrossRef]
  104. McGrath, T.; Chan, W.; Hajaligol, M. Low temperature mechanism for the formation of polycyclic aromatic hydrocarbons from the pyrolysis of cellulose. J. Anal. Appl. Pyrolysis 2003, 66, 51–70. [Google Scholar] [CrossRef]
  105. Meï, C.; Michaud, M.; Cussac, M.; Albrieux, C.; Gros, V.; Maréchal, E.; Block, M.; Jouhet, J.; Rébeillé, F. Levels of polyunsaturated fatty acids correlate with growth rate in plant cell cultures. Sci. Rep. 2015, 5, 15207. [Google Scholar] [CrossRef] [Green Version]
  106. Ji, J.M.; Liu, Y.L.; Ma, Y.X. Variations of Polycyclic Aromatic Hydrocarbons in Vegetable Oils During Seed Roasting Pre-Treatment. Polycycl. Aromat. Compd. 2020, 1–18. [Google Scholar] [CrossRef]
  107. Wongmaneepratip, W.; Vangnai, K. Effects of oil types and pH on carcinogenic polycyclic aromatic hydrocarbons (PAHs) in grilled chicken. Food Control 2017, 79, 119–125. [Google Scholar] [CrossRef]
  108. Hays, M.; Fine, P.; Geron, C.; Kleeman, M.; Gullett, B. Open burning of agricultural biomass: Physical and chemical properties of particle-phase emissions. Atmos. Environ. 2005, 39, 6747–6764. [Google Scholar] [CrossRef]
  109. Sharma, R.; Wooten, J.; Baliga, V.; Lin, X.; Geoffrey Chan, W.; Hajaligol, M. Characterization of chars from pyrolysis of lignin. Fuel 2004, 83, 1469–1482. [Google Scholar] [CrossRef]
  110. Schmidt, G.; Trouvé, G.; Leyssens, G.; Schönnenbeck, C.; Genevray, P.; Cazier, F.; Dewaele, D.; Vandenbilcke, C.; Faivre, E.; Denance, Y.; et al. Wood washing: Influence on gaseous and particulate emissions during wood combustion in a domestic pellet stove. Fuel Process. Technol. 2018, 174, 104–117. [Google Scholar] [CrossRef] [Green Version]
  111. Shen, G.F.; Xue, M.; Wei, S.Y.; Chen, Y.C.; Zhao, Q.Y.; Li, B.; Wu, H.S.; Tao, S. Influence of fuel moisture, charge size, feeding rate and air ventilation conditions on the emissions of PM, OC, EC, parent PAHs, and their derivatives from residential wood combustion. J. Environ. Sci. 2013, 25, 1808–1816. [Google Scholar] [CrossRef]
  112. Guerrero, F.; Yáñez, K.; Vidal, V.; Cereceda-Balic, F. Effects of wood moisture on emission factors for PM2.5, particle numbers and particulate-phase PAHs from Eucalyptus globulus combustion using a controlled combustion chamber for emissions. Sci. Total Environ. 2019, 648, 737–744. [Google Scholar] [CrossRef]
  113. Rogge, W.; Hildemann, L.; Mazurek, M.; Cass, G.; Simoneit, B.R. Sources of Fine Organic Aerosol. 9. Pine, Oak, and Synthetic Log Combustion in Residential Fireplaces. Environ. Sci. Technol. 1998, 32, 13–22. [Google Scholar] [CrossRef]
  114. Simoneit, B. Biomass burning—A review of organic tracers for smoke from incomplete combustion. Appl. Geochem. 2002, 17, 129–162. [Google Scholar] [CrossRef]
  115. Korenaga, T.; Liu, X.X.; Huang, Z.Y. The influence of moisture content on polycyclic aromatic hydrocarbons emission during rice straw burning. Chemosphere Glob. Chang. Sci. 2001, 3, 117–122. [Google Scholar] [CrossRef]
  116. Sanchis, E.; Ferrer, M.; Calvet, S.; Coscollà, C.; Yusà, V.; Cambra-López, M. Gaseous and particulate emission profiles during controlled rice straw burning. Atmos. Environ. 2014, 98, 25–31. [Google Scholar] [CrossRef] [Green Version]
  117. Noblet, C.; Besombes, J.; Lemire, M.; Pin, M.; Jaffrezo, J.; Favez, O.; Plouzeau, R.; Dermigny, A.; Karoski, N.; Elsuve, D.; et al. Emission factors and chemical characterization of particulate emissions from garden green waste burning. Sci. Total Environ. 2021, 798, 149367. [Google Scholar] [CrossRef] [PubMed]
  118. Zeng, X.Y.; Ma, Y.T.; Ma, L.R. Utilization of straw in biomass energy in China. Renew. Sustain. Energy Rev. 2007, 11, 976–987. [Google Scholar] [CrossRef]
  119. Stelte, W.; Sanadi, A.; Shang, L.; Holm, J.; Ahrenfeldt, J.; Henriksen, U. Recent developments in biomass pelletization—A review. BioResources 2012, 7, 4451–4490. [Google Scholar] [CrossRef]
  120. Nunes, L.; Matias, J.; Catalão, J. Mixed biomass pellets for thermal energy production: A review of combustion models. Appl. Energy 2014, 127, 135–140. [Google Scholar] [CrossRef]
  121. Shen, G.F.; Tao, S.; Wei, S.Y.; Zhang, Y.Y.; Wang, R.; Wang, B.; Li, W.; Shen, H.Z.; Huang, Y.; Chen, Y.C.; et al. Reductions in Emissions of Carbonaceous Particulate Matter and Polycyclic Aromatic Hydrocarbons from Combustion of Biomass Pellets in Comparison with Raw Fuel Burning. Environ. Sci. Technol. 2012, 46, 6409–6416. [Google Scholar] [CrossRef] [Green Version]
  122. Shen, G.F. Quantification of emission reduction potentials of primary air pollutants from residential solid fuel combustion by adopting cleaner fuels in China. J. Environ. Sci. 2015, 37, 1–7. [Google Scholar] [CrossRef]
  123. Singh, D.; Gadi, R.; Mandal, T.; Saud, T.; Saxena, M.; Sharma, S. Emissions estimates of PAH from biomass fuels used in rural sector of Indo-Gangetic Plains of India. Atmos. Environ. 2013, 68, 120–126. [Google Scholar] [CrossRef]
  124. Riojas-Rodriguez, H.; Schilmann, A.; Marron-Mares, A.; Masera, O.; Li, Z.; Romanoff, L.; Sjödin, A.; Rojas-Bracho, L.; Needham, L.; Romieu, I. Impact of the Improved Patsari Biomass Stove on Urinary Polycyclic Aromatic Hydrocarbon Biomarkers and Carbon Monoxide Exposures in Rural Mexican Women. Environ. Health Perspect. 2011, 119, 1301–1307. [Google Scholar] [CrossRef] [Green Version]
  125. Munyeza, C.; Osano, A.; Maghanga, J.; Forbes, P. Polycyclic Aromatic Hydrocarbon Gaseous Emissions from Household Cooking Devices: A Kenyan Case Study. Environ. Toxicol. Chem. 2020, 39, 538–547. [Google Scholar] [CrossRef]
  126. Zhang, Y.X.; Dou, H.; Chang, B.; Wei, Z.C.; Qiu, W.X.; Liu, S.Z.; Liu, W.X.; Tao, S. Emission of Polycyclic Aromatic Hydrocarbons from Indoor Straw Burning and Emission Inventory Updating in China. Ann. N. Y. Acad. Sci. 2008, 1140, 218–227. [Google Scholar] [CrossRef] [PubMed]
  127. Xu, S.S.; Liu, W.X.; Tao, S. Emission of Polycyclic Aromatic Hydrocarbons in China. Environ. Sci. Technol. 2006, 40, 702–708. [Google Scholar] [CrossRef] [PubMed]
  128. Ozgen, S.; Becagli, S.; Bernardoni, V.; Caserini, S.; Caruso, D.; Corbella, L.; Dell’Acqua, M.; Fermo, P.; Gonzalez, R.; Lonati, G.; et al. Analysis of the chemical composition of ultrafine particles from two domestic solid biomass fired room heaters under simulated real-world use. Atmos. Environ. 2017, 150, 87–97. [Google Scholar] [CrossRef] [Green Version]
  129. Du, W.; Wang, J.Z.; Zhuo, S.J.; Zhong, Q.R.; Wang, W.; Chen, Y.C.; Wang, Z.L.; Mao, K.; Huang, Y.; Shen, G.F.; et al. Emissions of particulate PAHs from solid fuel combustion in indoor cookstoves. Sci. Total Environ. 2021, 771, 145411. [Google Scholar] [CrossRef]
  130. Venkataraman, C.; Negi, G.; Brata Sardar, S.; Rastogi, R. Size distributions of polycyclic aromatic hydrocarbons in aerosol emissions from biofuel combustion. J. Aerosol Sci. 2002, 33, 503–518. [Google Scholar] [CrossRef]
  131. Lu, H.; Zhu, L.Z.; Zhu, N.L. Polycyclic aromatic hydrocarbon emission from straw burning and the influence of combustion parameters. Atmos. Environ. 2009, 43, 978–983. [Google Scholar] [CrossRef]
  132. Iinuma, Y.; Brüggemann, E.; Gnauk, T.; Müller, K.; Andreae, M.; Helas, G.; Parmar, R.; Herrmann, H. Source characterization of biomass burning particles: The combustion of selected European conifers, African hardwood, savanna grass, and German and Indonesian peat. J. Geophys. Res. Atmos. 2007, 112, D08209. [Google Scholar] [CrossRef]
  133. Vicente, E.D.; Vicente, A.M.; Evtyugina, M.; Oduber, F.I.; Amato, F.; Querol, X.; Alves, C. Impact of wood combustion on indoor air quality. Sci. Total Environ. 2020, 705, 135769. [Google Scholar] [CrossRef]
  134. De Gennaro, G.; Dambruoso, P.; Di Gilio, A.; Di Palma, V.; Marzocca, A.; Tutino, M. Discontinuous and Continuous Indoor Air Quality Monitoring in Homes with Fireplaces or Wood Stoves as Heating System. Int. J. Environ. Res. Public Health 2015, 13, 78. [Google Scholar] [CrossRef]
  135. Wei, S.Y.; Shen, G.F.; Zhang, Y.Y.; Xue, M.; Xie, H.; Lin, P.C.; Chen, Y.C.; Wang, X.L.; Tao, S. Field measurement on the emissions of PM, OC, EC and PAHs from indoor crop straw burning in rural China. Environ. Pollut. 2014, 184, 18–24. [Google Scholar] [CrossRef] [Green Version]
  136. Shen, G.F.; Chen, Y.C.; Xue, C.Y.; Lin, N.; Huang, Y.; Shen, H.Z.; Wang, Y.L.; Li, T.C.; Zhang, Y.Y.; Su, S.; et al. Pollutant Emissions from Improved Coal- and Wood-Fuelled Cookstoves in Rural Households. Environ. Sci. Technol. 2015, 49, 6590–6598. [Google Scholar] [CrossRef] [PubMed]
  137. Fuchs, J.; Schmid, J.; Müller, S.; Mauerhofer, A.; Benedikt, F.; Hofbauer, H. The impact of gasification temperature on the process characteristics of sorption enhanced reforming of biomass. Biomass Convers. Biorefinery 2020, 10, 925–936. [Google Scholar] [CrossRef] [Green Version]
  138. Akhavan, O.; Bijanzad, K.; Mirsepah, A. Synthesis of graphene from natural and industrial carbonaceous wastes. RSC Adv. 2014, 4, 20441–20448. [Google Scholar] [CrossRef]
  139. Jouyandeh, M.; Tavakoli, O.; Sarkhanpour, R.; Sajadi, S.; Zarrintaj, P.; Rabiee, N.; Akhavan, O.; Lima, E.; Saeb, M. Green products from herbal medicine wastes by subcritical water treatment. J. Hazard. Mater. 2022, 424, 127294. [Google Scholar] [CrossRef] [PubMed]
  140. Wahyudiono, W.; Machmudah, S.; Goto, M. Utilization of Sub and Supercritical Water Reactions in Resource Recovery of Biomass Wastes. Eng. J. 2013, 17, 1–12. [Google Scholar] [CrossRef]
  141. Zhang, H.W.; Wang, C.Y.; Zhang, X.M.; Zhang, R.H.; Ding, L. Formation and inhibition of polycyclic aromatic hydrocarbons from the gasification of cyanobacterial biomass in supercritical water. Chemosphere 2020, 253, 126777. [Google Scholar] [CrossRef]
  142. Jetter, J.; Zhao, Y.; Smith, K.; Khan, B.; Yelverton, T.; DeCarlo, P.; Hays, M. Pollutant Emissions and Energy Efficiency under Controlled Conditions for Household Biomass Cookstoves and Implications for Metrics Useful in Setting International Test Standards. Environ. Sci. Technol. 2012, 46, 10827–10834. [Google Scholar] [CrossRef]
  143. Riva, G.; Pedretti, E.; Toscano, G.; Duca, D.; Pizzi, A. Determination of polycyclic aromatic hydrocarbons in domestic pellet stove emissions. Biomass Bioenergy 2011, 35, 4261–4267. [Google Scholar] [CrossRef]
  144. Szramowiat-Sala, K.; Korzeniewska, A.; Sornek, K.; Marczak, M.; Wierońska, F.; Berent, K.; Gołaś, J.; Filipowicz, M. The properties of particulate matter generated during wood combustion in in-use stoves. Fuel 2019, 253, 792–801. [Google Scholar] [CrossRef]
Table
Table 1. Top three industries in PAHs emissions in different countries and around the world.
Table 1. Top three industries in PAHs emissions in different countries and around the world.
RegionFirst PAH Emissions 1Second PAH Emissions 1Third PAH Emissions 1
IndustryAmount (Gg)IndustryAmount (Gg)IndustryAmount (Gg)
WorldIBB 2293Motor Vehicle64.5Wildfire56.4
ChinaIBB57.7Coke burning13.8Motor Vehicle13.4
IndiaIBB55.8Motor Vehicle5.03BOB 32.35
BrazilWildfire17.4IBB5.13Motor Vehicle4.35
IndonesiaIBB15.4Motor Vehicle2.89Wildfire0.43
RussiaMotor Vehicle2.83Wildfire1.87Industry1.11
AngolaWildfire3.49IBB0.86Motor Vehicle0.14
The United StatesIBB4.96Motor Vehicle1.50Wildfire1.02
1 Shen et al. [35]; 2 IBB: Indoor biomass burning; 3 BOB: Biomass open burning.
Table
Table 2. Comparison of the EFs of PAHs emission from traditional fuels and biomass fuels.
Table 2. Comparison of the EFs of PAHs emission from traditional fuels and biomass fuels.
Traditional Fuel Biomass FuelReference
Fuel TypeEFs
(mg/kg)		Fuel Type EFs
(mg/kg)
Anthracite2.1Mixed wood60.6[40]
Mixed coal119.1Mixed wood38.9[43]
Mixed coal15.5Crop residue pellets43.9[44]
Anthracite and bituminous123.1Crop residue and wood191.1[54]
Table
Table 3. Comparison of the concentration of PAHs in non-burning period with open burning period.
Table 3. Comparison of the concentration of PAHs in non-burning period with open burning period.
PAHs NumberCitiesNon-Burning Period
(ng/m3)		Open Burning Period
(ng/m3)		Reference
16Taichung, China11.0 ± 1.5130.8 ± 3.93[41]
9Hanoi, Vietnam14.4 ± 3.694488 ± 3850[53]
9Hanoi, Vietnam2.60 ± 1.313064 ± 2370[53]
16Bangkok, Thailand 32.4 ± 17.1108 ± 25.7[66]
14Klong Luang, Thailand43.4 ± 20.0414 ± 24.0[67]
Table
Table 4. Comparison of the concentration of PAHs in non-cooking with cooking.
Table 4. Comparison of the concentration of PAHs in non-cooking with cooking.
PAHs NumberCitiesNon-Cooking
(ng/m3) 		Cooking
(ng/m3) 		Reference
7Lucknow, India1120 ±190 9110 ± 3570[73]
7Lucknow, India3530 ± 890 15600 ± 2950[73]
15Laiyang, China513 ± 225 696 ± 230[74]
16Nanyang, China210 ± 23.4 443 ± 59.7[75]
15Zhuanghu, China1530 ± 244 2660 ± 1120[76]
Table
Table 5. Comparison of PAHs concentration in the non-heating period with heating period.
Table 5. Comparison of PAHs concentration in the non-heating period with heating period.
PAHs
Number		CitiesNon-Heating Period (ng/m3)Heating Period (ng/m3)Reference
10Zagreb, Croatian0.5441.2[80]
15Warsaw, Poland (Outdoor)36.0106[81]
15Warsaw, Poland (Indoor)131461[81]
10Delnice, Croatia (Rural)0.8048.5[82]
10Delnice, Croatia (Urban)0.4021.7[82]
9Rome, Italy1.2810.6[83]
9Augsburg, Germany0.4413.0[84]
Table
Table 6. Composition of the PAHs in different studies in normal period and biomass burning period.
Table 6. Composition of the PAHs in different studies in normal period and biomass burning period.
City4-Ring PAHs
(ng/m3)		5-Ring PAHs
(ng/m3)		6-Ring PAHs
(ng/m3)		Total PAHs
(ng/m3)		Reference
Tainan, China6.640.561.122.83[49]
Hanoi, Vietnam40121986.0311[53]
Baoding, China3.893.583.273.59[86]
Table
Table 7. The ignition, peak and burnout temperature of biomass.
Table 7. The ignition, peak and burnout temperature of biomass.
BiomassIgnition (°C)Peak (°C)Burnout (°C)Reference
Oat straw260300512[87]
Wheat straw 227281436[88]
Wheat husk242299490[88]
cotton stalks261294480[89]
Table
Table 8. Emission factors and composition of PAHs from the burning of different biomass in the same conditions.
Table 8. Emission factors and composition of PAHs from the burning of different biomass in the same conditions.
3-Ring4-Ring5-Ring6-RingTotal PAHs (mg/kg)StoveReference
Rice Straw 49%38%8%4%42.5Brick cooking stove[90]
Wheat Straw63%28%6%3%65.2
Corn Straw60%30%7%3%19.0
Dung Cakes30%44%16%11%53.8Open burning[91]
Charcoal21%47%19%13%27.3
Crop residue66%26%6%3%30.0Brick cooking stove[93]
Fuel wood59%33%5%2%6.76
Brushwood38%42%12%7%47.1
Ceanothus37%34%23%6%6.47Laboratory burning stove[94]
California sage5%47%39%8%11.7
Coastal sage6%49%30%15%11.3
Table
Table 9. The emission of PAHs under the burning of same biomass contains different volatile matter in the same stove during the laboratory-simulated stove burning.
Table 9. The emission of PAHs under the burning of same biomass contains different volatile matter in the same stove during the laboratory-simulated stove burning.
BiomassVolatile Matter (wt%)PAHs (μg/g)Reference
Maize straw (Raw)76.007.70[96]
Maize straw (Carbonization)25.011.10
wheat straw (Raw)67.3618.8
wheat straw (Carbonization)16.951.60
Wood branch (Raw)82.968.70
Wood branch (Carbonization)44.942.90
Wheat straw (Raw)73.27213[101]
Wheat straw (Carbonization)29.9913.1
Rice Straw (Raw)71.53189
Rice Straw (Carbonization)25.6718.2
Maize Straw (Raw)74.22203
Maize Straw (Carbonization)28.264.03
Sawdust (Raw)77.47241
Sawdust (Carbonization)38.444.73
Table
Table 10. The EF and composition of PAHs at different biomass moisture content.
Table 10. The EF and composition of PAHs at different biomass moisture content.
Moisture (%)Total PAHs (mg/kg)Reference
03.19 × 10−3[112]
255.57 × 10−3
033.87[115]
54.22
102.42
151.75
204.06
253.43
305.42
53.02[116]
108.14
2017.1
153.20[117]
2524.3
Table
Table 11. Emission factors of PAHs of the same biomass burning in different stoves.
Table 11. Emission factors of PAHs of the same biomass burning in different stoves.
Stove TypePAHs EFs (mg/kg)Reference
Top-feed pellet stove0.04[128]
Wood stove0.96
Gasifier wood stove31.2[129]
Guizhou brick stove132
Sichuan brick stove262
Metal stove5.50[130]
Grihalaxmi stove3.80
Traditional stove3.10
Table
Table 12. Relative changes in PAH composition from rice and bean burning at different temperatures.
Table 12. Relative changes in PAH composition from rice and bean burning at different temperatures.
PAHsR300/200 1,2R400/200 2R500/200 2R600/200 2R700/200 2
Rice
3-ring 1.481.501.742.522.63
4-ring1.682.433.726.267.35
5-ring1.811.952.543.043.15
6-ring2.331.562.242.113.35
Bean
3-ring1.061.283.545.1716.1
4-ring0.871.192.044.109.16
5-ring0.750.991.832.9319.7
6-ring1.011.041.452.4624.5
1 Represents the result of PAHs EF values of biomass burning in 300 °C divided with PAHs EF values of biomass burning in 200 °C; 2 Lu et al. [131].
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Share and Cite

MDPI and ACS Style

Zhang, H.; Zhang, X.; Wang, Y.; Bai, P.; Hayakawa, K.; Zhang, L.; Tang, N. Characteristics and Influencing Factors of Polycyclic Aromatic Hydrocarbons Emitted from Open Burning and Stove Burning of Biomass: A Brief Review. Int. J. Environ. Res. Public Health 2022, 19, 3944. https://doi.org/10.3390/ijerph19073944

AMA Style

Zhang H, Zhang X, Wang Y, Bai P, Hayakawa K, Zhang L, Tang N. Characteristics and Influencing Factors of Polycyclic Aromatic Hydrocarbons Emitted from Open Burning and Stove Burning of Biomass: A Brief Review. International Journal of Environmental Research and Public Health. 2022; 19(7):3944. https://doi.org/10.3390/ijerph19073944

Chicago/Turabian Style

Zhang, Hao, Xuan Zhang, Yan Wang, Pengchu Bai, Kazuichi Hayakawa, Lulu Zhang, and Ning Tang. 2022. "Characteristics and Influencing Factors of Polycyclic Aromatic Hydrocarbons Emitted from Open Burning and Stove Burning of Biomass: A Brief Review" International Journal of Environmental Research and Public Health 19, no. 7: 3944. https://doi.org/10.3390/ijerph19073944

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop