Pollutants

Perfluoroalkyl substances (PFAS), also known as “forever chemicals”, are a class of highly stable chemical compounds that slowly contaminate waterbodies and soil. The widespread presence of PFAS is associated with adverse human health effects and is a major environmental concern. The conventional, highly sensitive methods used for PFAS detection are LC-MS/MS and solid phase extraction, but they are very complex and expensive. Therefore, there is an urgent need for sensitive, low-cost, and fast methods for the detection and removal of PFAS compounds from water and soil resources. The advancement of nanotechnology has significantly impacted advanced disease diagnosis and treatment in the last few decades. Currently, these engineered nanomaterials (ENMs) have been exploited for the development of advanced nano-enabled techniques for the detection and removal of environmental pollutants. Nano-enabled techniques also offer improved performance over conventional methods. In this review, the details of the detection and removal of PFAS, as well as their optimization and limitations, and future perspectives are discussed. We focused on the implementation of nanomaterials such as nanoparticles, nanotubes, nanorods, and nano*filtration membranes for efficient PFAS detection and removal. We also included the recent literature and global guidelines for PFAS use and the effect of PFAS exposure on human health. Full article

Exposure to contaminated soils can adversely affect health and the well-being of both humans and animals. Environmental stressors can influence the mobility and toxicity of contaminants, altering their potential impacts. This study aimed to assess the impact on the behavior of offspring from rats exposed during the gestation and lactation period to contaminated and acidified soils. Female Wistar rats were gavaged daily for 42 days with soil leachate from an industrial region known to be contaminated with metals and metalloids, using solvents with different pH values (6.0, 5.2, and 3.6). The offspring were evaluated in behavioral tests including Open Field, Elevated Plus Maze, and Inhibitory Avoidance. Our findings revealed significant statistical differences in all three tests conducted, indicating that the exposed groups exhibited lower exploratory behavior, higher anxiety behavior, and lower memory retention than the control groups. The difference was more pronounced in the soil leachate with acidified solvent, at both pH 5.2 and 3.6, suggesting that the combined effect of both stressors led to synergistic interactions, potentiating their impacts. Elemental analysis revealed elevated levels of neurotoxic metals, including Cr, Cu, and Ni, as well as the metalloid As, with acidification significantly enhancing their bioavailability. Moreover, our results demonstrate that acidification facilitated the mobilization of metals and the metalloid As, increasing their bioavailability and acting synergistically to exacerbate the behavioral impacts of contaminated soils. Special attention should be given to populations living in industrial areas that may be exposed to contaminated soils. Full article

The prevalence of hyperthyroidism in cats has been steadily increasing worldwide since the late 1970s. The main cause of feline hyperthyroidism remains unknown. The underlying cause was studied from the viewpoint of the “One Health” concept, which is an approach integrating environmental, animal and human health. Looking at the dietary difference between cats which are carnivores and dogs which appear to be omnivores like humans, there is a possibility that cats take in a comparatively greater amount of endocrine-disrupting chemicals such as polybrominated diphenyl ethers (PBDEs) than dogs and humans via the fish-based food web. PBDEs have been used worldwide as flame retardants since the 1970s. It is considered that PBDEs mimic thyroid-stimulating hormones to cause a thyroid adenoma, which is often active and produces excessive thyroid hormones, resulting in symptomatic hyperthyroidism. The increasing prevalence of feline hyperthyroidism may be associated with Minamata disease that was caused by methyl-mercury contamination in the 1950s. This environmental contamination firstly wreaked havoc as neurological disorders in local cats, and this occurrence was a sign that severe neurological disorders would next develop in large numbers of local people. The prevalence of feline hyperthyroidism may be a sign of what will next emerge in human beings. Full article

This study evaluated heavy metal (HM) contamination in sediments from the Malbasag River in the Ormoc City port, Leyte, Philippines. A total of thirty sediment samples were collected randomly from ten locations along the river using an Ekman grab sampler. Atomic absorption spectrophotometry revealed HM concentrations in the order of Mn > Zn > Cu > Ni > Pb > Cd. All HMs exceeded their sediment quality guideline (SQG) thresholds except for Mn. Contamination was assessed using indices such as the contamination factor (CF), pollution load index (PLI), geo-accumulation index (I_geo), and enrichment factor (EF). The CF values indicated “moderate to considerable” contamination for Zn, Ni, and Cd, while Cu and Pb showed “very high” contamination levels. The PLI results indicated severe sediment degradation in 20% of samples. The I_geo analysis classified 60% of the samples as “heavily to extremely polluted” for Cd, Cu, and Pb. EF analysis suggested that anthropogenic sources contributed to elevated HM levels, including port activities and agricultural runoff. Ecological risk index (RI) analysis revealed moderate risk in 40% and considerable risk in 20% of sampling locations. Multivariate analyses suggested significant anthropogenic contributions to HM contamination, highlighting the need for further studies to assess the ecological impacts. Full article

The recent increase in industrial activities has raised concerns regarding environmental quality in urban areas in Malawi. In this study, the contents of heavy metals [copper (Cu), zinc (Zn) and cadmium (Cd)] were analysed in 15 sites selected from Makata, Limbe, Maselema, Chirimba, and Maone industrial zones of Blantyre City in Malawi. Soil sampling was conducted during dry and rainy seasons, followed by laboratory analysis. The results revealed a few cases of elevated content of heavy metals exceeding permissible England and Canadian standards with higher content detected during the dry season than in the rainy season. Chirimba soil had the highest mean Zn content of 822 mg/kg in the rainy season and 579 mg/kg in the dry season. Maone soils had the highest Cd content, measuring 2.09 mg/kg in the rainy season and 3.06 mg/kg in the dry season. Chirimba soils also had the highest Cu content with levels of 105 mg/kg in the dry season and 79 mg/kg in the rainy season. The geo-accumulation index indicated that Zn posed the most severe pollution. The results of the Positive Matrix Factorisation model suggest that heavy metal pollution primarily originates from metal processing and manufacturing industries, followed by plastic manufacturing industries. This finding is supported by the nature of emissions from these sectors, where metal processing activities release heavy metals through particulates and waste to the environment, suggesting collective actions to prevent soil contamination. Full article

This paper focuses on the environmental impact of urban surface transportation and the influence that driving mode and drivers’ attitudes have on it. This article emphasizes the importance of a respectful attitude toward the environment and adopting moderate or conservative driving modes. This study covers driving GHG emissions in urban and peripheral areas for variable driving conditions, evaluating reductions or increases in CO₂ emissions depending on the way of driving. The analysis of the different cases shows that pollutant emissions are significantly lower if a car driver reduces the acceleration rate and slows down by 10 to 20 km/h, or 6 to 12 mph, depending on the urban zone, downtown or peripheral, and traffic conditions. The reduction in GHG emissions can be as high as 0.083 kg of CO₂ per day, on average, representing a global yearly reduction of 30 kg of GHG emissions per vehicle. This paper analyzes how inadequate driving speed and the above traffic regulation limits have caused a surplus in GHG emissions and a severe impact on urban areas, which are sensitive to pollution, increasing the GHG emission rate by between 28% and 40% depending on driving mode and driver attitude. This study shows that vehicle speed reduction did not significantly increase traveling time, with an average time extension of 0.2 min per km, representing a global extended daily traveled time of 6.4 min for the average daily journey distance in many countries. GHG increases due to inadequate driving increase the early human mortality rate by 0.4%, representing nearly 35 million early deaths per year. Full article

Two sets of sediment samples were collected from the Sarigiol basin, Greece, aiming to evaluate the environmental consequences of the industrial activity in the area by assessing their magnetic properties with the magnetic susceptibility method. Chemical composition and morphological characteristics of magnetic particles were defined by EDX analysis and scanning electron microscopy, respectively. Based on the results, most of the study area shows positive values of the difference between X_LF values of the samples, indicating the influence of fly ash dispersion from Agios Dimitrios and Kardia power plants and the conveyor belt, down to a depth of 50 cm. Negative values in the NE, W and S parts of the study area are attributed to ophiolite complexes. Anthropogenic and lithogenic magnetic particles were identified at a 50 cm depth, in the form of spheres and octahedrons, respectively. Fe is the dominant element while Al, Si, Mg and Ca were found in minor amounts. Cr increases with depth, pointing mainly to a lithogenic source, while Ti decreases, suggesting a relationship with the dispersed fly ash particles. Mn and Zn were found in limited magnetic spheres. These findings highlight the need for effective environmental management strategies and are valuable keys for soil pollution control. Full article

Air pollution in urban centers comes from anthropogenic activities. Tropospheric ozone (O₃) depends on chemical precursors that promote an increase in its production, mainly in wind-dominated and large green areas. It is a gas produced by a series of complex chemical reactions catalyzed by sunlight in the atmosphere. It can be concentrated to a greater or lesser extent depending on factors such as the amount of volatile organic compounds (VOCs), the amount of nitrogen dioxide (NO₂), the intensity of solar radiation, or by climatic conditions such as temperature and other factors. The objective of this study was to predict tropospheric ozone levels from Land Surface Temperature (LST) data of Landsat 8 in the city of Durango, Dgo. Tropospheric O₃ and LST values were obtained from 14 sampling points in the urban area of the city of Durango, of which 11 were obtained by collecting from temperature-monitoring station data and the rest from three fixed monitoring stations established in the city, specifically located in Ministry of Natural Resources and Environment (SRNyMA), Durango Institute of Technology (ITD) and Interdisciplinary Research Center for Regional Integral Development Durango Unit (CIIDIR). A correlation analysis was performed for the 12 months of the year 2023. Subsequently, a linear regression analysis was executed for each month. The results showed a greater positive correlation between O₃ concentration and temperature for January (r = 0.91); additionally, this period showed a greater goodness of fit in the prediction of O₃ (R² = 0.91; RMSE = 0.65 ppm). The LST allows for the spatial prediction of ozone concentrations in terms of covering complete urban areas without measuring air stations. Full article

Differences in exposures and resources to manage personal health contribute to persistent inequities in air pollution burden despite vast air quality improvements over the past 2–3 decades in the United States. These factors are, partly, linked to historic racist practices, such as redlining, a discriminatory housing policy that was practiced legally between 1935 and 1968. Using 100 m × 100 m resolution land-use regression predicted surfaces of PM_2.5 constituents (black carbon, nickel, vanadium, and copper) as pollution source indicators, we fit Bayesian generalized linear mixed-effects models to examine differences in source exposures over two study periods, 2008–2015 and 2016–2019, comparing (1) redlined to not redlined and (2) high-asthma to low-asthma neighborhoods. We examine redlining as an indicator of historical, and structural racism and asthma rates as an indicator of present-day community burden. Redlined areas saw near elimination of disparities in exposure to residual oil boilers and marine residual oil but persistent disparities in traffic. High-asthma neighborhoods continue to have disproportionately high exposures to both residual oil boilers and traffic, with no discernable disparities related to marine residual oil emissions. Overall exposure disparities are small, with PM_2.5 disparities by both asthma morbidity and redlining amounting to less than 1 µg/m³ and NO₂ disparities by asthma and redlining amounting to less than 2 ppb in the post-2016 period. For context, 2019 NYC average PM_2.5 and NO₂ were 8.5 µg/m³ and 20 ppb, respectively. Our findings suggest that local pollution policy should focus on reducing traffic and building boiler emissions in high-asthma neighborhoods to reduce exacerbations. Full article

Acid mine drainage (AMD), which is primarily caused by the exposure of sulfidic minerals to oxygen and water during mining operations, remains a significant contributor to environmental pollution. Numerous technologies have been developed to prevent/control and treat AMD, including the isolation of waste from the atmosphere and treatment systems for AMD-impacted water. Many field studies on mine site reclamation have involved an individual AMD source and/or technology, with a limited number of studies looking at reclamation programs integrating multiple approaches to manage AMD stemming from both surface and underground sources. The former Franklin mine site in Nova Scotia, Canada, was impacted by the deposition of waste rock across the site and the discharge of mine water from underground workings, with the adjacent Sullivan’s Pond serving as the main environmental receptor. Site reclamation was completed in 2010 and involved the following: (1) excavation of the dispersed waste rock (117,000 m²) and backfilling with clean soil; (2) consolidation of the excavated waste rock into a covered, compact waste rock pile (WRP) (25,000 m²); and (3) construction of a passive treatment system for the discharging underground mine water. An extensive field sampling program was conducted between 2011 and 2018 to monitor a range of meteorological, cover material, waste rock, groundwater, and surface water quality parameters. The results confirm that the multi-layer, geomembrane-lined WRP cover system is an extremely effective barrier to air and water influx, thereby minimizing the rate of AMD generation and seepage into groundwater and eliminating all contaminated surface water runoff. A small AMD groundwater plume emanates from the base of the WRP, with 50% captured by the underground mine workings over the long term and 50% slowly migrating towards Sullivan’s Pond. Excavation of the former waste disposal area eliminated the AMD source from the previously dispersed waste, with only clean surface water runoff and a diminishing legacy groundwater plume remaining. Finally, the passive treatment system, which contains a series of treatment technologies such as a limestone leach bed and settling pond, successfully treats all mine water loading (~50 kg/day) discharging from the underground workings and surface runoff. Its additional treatment capacity (up to ~150 kg/day) ensures it will be able to manage any potential drop in treatment efficiency and/or increased AMD loading from long-term WRP seepage. This comprehensive study of mine site reclamation and AMD management at an abandoned mining site can be of great reference value for environmental management and policymakers in the mining sector. Full article

Cigarette butts (CBs) are emerging soil contaminants, releasing chemicals upon contact with moisture. This study examined heavy metal concentrations leached from smoked and unsmoked CBs (Pall Mall, Philip Morris, and Marlboro) into OECD artificial soil and Vertisol soil and their accumulation in white mustard (Sinapis alba L.). Key physiological parameters, including germination rate, plant height, fresh weight, and dry weight, were analyzed, along with the uptake of heavy metals (Al, Fe, Mn, Zn, Ba, Ti, and Cu) and essential elements (Ca, Mg, Na, and K). Results showed that Mn had the highest bioaccumulation index (BAI = 1.10) in OECD soil, while Zn uptake was consistently high across soil types. Soil type significantly influenced plant height (χ² = 41.269, p < 0.01) and elemental composition, with Vertisol soil facilitating greater overall growth and heavy metal uptake than OECD soil. MANOVA revealed no three-way interaction among soil type, CB use, and CB brand on elemental uptake. However, two-way interactions, particularly between soil type and CB use (F (4, 39) = 40.233, p < 0.001, Wilk’Λ = 0.195), showed significant effects on heavy metal uptake. These findings highlight the complex interactions influencing plant contamination, underlining the ecological risks of CB pollution in soils. Full article

Analyzing the fluctuations of particulate matter (PM) concentrations and their scaling correlation structures are useful for air quality management. Multifractal characterization of PM2.5 and PM10 of three cities in India wase considered using the detrended fluctuation procedure from 2018 to 2021. The cross-correlation of PM concentration in a multifractal viewpoint using the multifractal cross-correlation analysis (MFCCA) framework is proposed in this study. It was observed that PM2.5 was more multifractal and complex than PM10 at all the locations. The PM–gaseous pollutant (GP) and PM–meteorological variable (MV) correlations across the scales were found to be weak to moderate in different cities. There was no definite pattern in the correlation of PM with different meteorological and gaseous pollutants variables. The nature of correlation in the pairwise associations was found to be of diverse and mixed nature across the time scales and locations. All the time series exhibited multifractality when analyzed pairwise using multifractal cross-correlation analysis. However, there was a reduction in multifractality in individual cases during PM–GP and PM–MV paired analyses. The insights gained into the scaling behavior and cross-correlation structure from this study are valuable for developing prediction models for PMs by integrating them with machine learning techniques. Full article

Microplastics, defined as plastic particles less than 5 mm in size, have become a pervasive environmental contaminant detected across a wide range of ecosystems. While the presence of microplastics in marine life and humans has been extensively documented, there remains a significant gap in understanding their full health impacts. Moreover, the effects of microplastics on animals, particularly those in close proximity to human activities, remain underexplored, representing a key area for future research. In this study, we found high levels of microplastic accumulation in animal tissues, particularly in the lungs, intestines, and reproductive organs. Our results also indicate that ingestion of microplastics occurs through multiple environmental sources, including contaminated food, water, and air, reflecting their widespread distribution. Evidence of microplastics crossing biological barriers and accumulating in critical organ systems suggests potential long-term health risks for animals that may also have implications for humans through environmental and food-chain exposure. Given the interconnectedness of ecosystems and the potential for these contaminants to enter the food chain, the presence of microplastics in animals raises serious concerns for broader ecological and human health. The findings underscore the urgent need for further research to clarify the long-term effects and to develop effective strategies for mitigating this emerging global threat. Full article

Atmospheric pollution of metals negatively impacts the health of terrestrial and aquatic plants and animals. Despite implementation of policies that have substantially decreased emissions of metal pollutants, their legacy continues in temperate forest ecosystems across the globe. Here, we evaluated throughfall and litterfall concentrations and fluxes of Cu, Zn, Cd, and Pb via in rural temperate forests along the Appalachian Mountain range in eastern United States. Our five years of data show that throughfall fluxes of Cu, Cd, and Pb have decreased >89% since the 1980s. However, throughfall Zn and litterfall Cu, Zn, and Cd fluxes remain comparable or greater than the 1980s. These results suggest that Cd, Cu, and Pb emissions have decreased, but trees retain and recycle Cd, Cu, and Zn pollution, extending their legacy for decades following the emission. Full article

The Tula industrial area in Central Mexico comprises, among other industries, a refinery and a thermoelectric power plant. It is well known for its constant emissions of gases into the atmosphere and considered an important area where pollutants released into the atmosphere have an influence on local and regional air quality. During March and April 2017, a field campaign was conducted with the objective of quantifying formaldehyde (HCHO), sulfur dioxide (SO₂), and nitrogen dioxide (NO₂) emissions from this industrial area using mobile differential optical absorption spectroscopy (DOAS) instruments. Calculated average emissions of the Francisco Perez Rios Power Plant and the Miguel Hidalgo Refinery were 3.14 ± 2.13 tons per day of HCHO, 362.08 ± 300.14 tons per day of SO₂, and 24.76 ± 12.82 tons per day of NO₂. From the measurements conducted, the spatial distribution patterns of SO₂, NO₂, and HCHO were reconstructed, showing a dispersion pattern of SO₂ and NO₂ towards the southwest of the industrial complex, impacting agricultural and urban areas. Occasionally, and usually during the morning hours, SO₂ and NO₂ were dispersed towards the north or northeast of the industrial complex. In the case of HCHO, dispersion was observed towards the south and southeast of the industrial complex. The far-reaching implications of this study are that for the first time, formaldehyde emissions were quantified. In addition, a follow-up study was conducted regarding nitrogen dioxide and sulfur dioxide emissions from the Tula Industrial area. Full article

Nitrite is a common pollutant in marine environments and can cause mortality in crustaceans and bivalves. The purpose of the current study is to understand nitrate’s toxicity to juvenile clams due to its potential impact on aquaculture and marine ecosystems. Juvenile sunray surf clams (Mactra chinensis Philippi) (1.00 ± 0.10 cm shell length, 0.75 ± 0.04 cm shell height) were exposed to varying concentrations of nitrite for 96 h and 20 days, respectively. The LC₅₀ for survival at 96 h was 37 mg/L NO₂-N. Histological evaluations were made on juvenile clams exposed at 30 mg/L after 20 d of exposure. Epithelial cells and digestive diverticulum are the best sub-lethal effect indicators. Shell length and antioxidant enzyme activities were measured at the beginning of the experiment and then observed 10 and 20 days after exposure. A logarithmic relationship was obtained between the relative growth rate (based on the shell length) of juvenile M. chinensis and the nitrite concentration. Compared to the control, activity suppression of superoxide dismutase and catalase activity was detected from the concentration of 1 mg/L NO₂-N. It is recommended that nitrite concentrations remain below 1 mg/L to prevent stress during the early developmental stages of clams. Full article

This work aims to assess the bioavailability and bioaccumulation of Cr, Cu, Pb, and Zn in the soil–plant system (Erigeron canadensis L.) in the zone of anthropogenic impact in Dnipro city, a significant industrial and economic centre of Ukraine. Sampling was carried out at three locations at distances of 1.0 km, 5.5 km, and 12.02 km from the main emission sources associated with battery production and processing plants in Dnipro. The concentrations of heavy metals such as Cr, Cu, Pb, and Zn were analysed using atomic emission spectrometry from soil and parts of Erigeron canadensis L. The highest concentrations of elements in the soil, both for the mobile form and the total form, were determined to be 48.96 mg kg⁻¹ and 7830.0 mg kg⁻¹, respectively, for Pb in experimental plot 1. The general ranking of accumulation of elements in all experimental plots, both for the plant as a whole and for its parts, was as follows: Zn > Cu > Cr > Pb. Zn for plants was the most available heavy metal among all studied sites and had the highest metal content in the plant (339.58 mg kg⁻¹), plant uptake index (PUI-506.84), bioabsorption coefficient (BAC-314.9), and bioconcentration coefficient (BCF-191.94). According to the results of the study, it is possible to evaluate Erigeron canadensis L. as a hyperaccumulator of Zn, Cu, and Cr and recommend it for phytoextraction of soils contaminated with Zn, Cu, and Cr and phytostabilization of soils contaminated with Pb. Full article

The emergence of infectious disease outbreaks and ‘superbugs’ related to pollution combined with climate change is a current problem, not just a future threat. In May 2024, an extreme flood hit the Rio Grando Sul State, southern Brazil, triggering an important leptospirosis outbreak in urban settings with deficient sanitation systems. This and other cases discussed in this article exemplify how extreme weather events exacerbate the consequences of environmental pollution by multiple classes of pathogens in the global scenario of increasing anthropogenic pressures on the environment. A combination of actions to combat climate change and improvements in sanitation systems is essential to mitigate this problem. Full article

Aquaculture and waste valorization have the potential to show solid achievements toward food security and improvements in the circularity of resources, which are crucial aspects of achieving a sustainable lifestyle in agreeance with Agenda 2030 goals. This study aims to optimize and simplify the decision-making processes for the valorization of marine wastes (natural and from aquaculture) as secondary raw materials to produce high-value-added market goods. However, significant concentrations of pollutants may be present within wastes, compromising overall quality, and social dynamics can hinder their usage further. Goro’s lagoon was chosen as a case study, where the relations between the ecosystem services, a thriving bivalve economy, and social dynamics are deeply rooted and intertwined. Therefore, in the manuscript cost–benefit and foresight analyses are conducted to determine the best usage for algal biomass considering pollution, social acceptance, and profitability. These analyses are virtually conducted on bio-refineries that could be operating in the case study’s area: briefly, for a thirty-year running bio-plant, the CBA indicates the two best alternatives with an income of 5 billion euros (NPV, with a 5% discount rate) for a biofuel-only production facility, and a half for a multiproduct one, leading to the conclusion that the first is the best alternative. The foresight, instead, suggests a more cautious approach by considering external factors such as the environment and local inhabitants. Hence, the main innovation of this work consists of the decision-maker’s holistic enlightenment toward the complexities and the hidden threats bound to this kind of closed-loop efficiency-boosting process, which eventually leads to optimized decision-making processes. Full article