Toxics

1466 KiB

Open AccessArticle

UNMIX Methods Applied to Characterize Sources of Volatile Organic Compounds in Toronto, Ontario

by Eugeniusz Porada and Mieczysław Szyszkowicz

Toxics 2016, 4(2), 11; https://doi.org/10.3390/toxics4020011 - 18 Jun 2016

Cited by 6 | Viewed by 6705

UNMIX, a sensor modeling routine from the U.S. Environmental Protection Agency (EPA), was used to model volatile organic compound (VOC) receptors in four urban sites in Toronto, Ontario. VOC ambient concentration data acquired in 2000–2009 for 175 VOC species in four air quality monitoring stations were analyzed. UNMIX, by performing multiple modeling attempts upon varying VOC menus—while rejecting the results that were not reliable—allowed for discriminating sources by their most consistent chemical characteristics. The method assessed occurrences of VOCs in sources typical of the urban environment (traffic, evaporative emissions of fuels, banks of fugitive inert gases), industrial point sources (plastic-, polymer-, and metalworking manufactures), and in secondary sources (releases from water, sediments, and contaminated urban soil). The remote sensing and robust modeling used here produces chemical profiles of putative VOC sources that, if combined with known environmental fates of VOCs, can be used to assign physical sources’ shares of VOCs emissions into the atmosphere. This in turn provides a means of assessing the impact of environmental policies on one hand, and industrial activities on the other hand, on VOC air pollution. Full article

(This article belongs to the Special Issue Air Toxics)

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948 KiB

Open AccessArticle

Development of a Biomarker for Penconazole: A Human Oral Dosing Study and a Survey of UK Residents’ Exposure

by Craig Sams, Kate Jones, Karen S. Galea, Laura MacCalman, John Cocker, Paul Teedon, John W. Cherrie and Martie Van Tongeren

Toxics 2016, 4(2), 10; https://doi.org/10.3390/toxics4020010 - 13 May 2016

Cited by 7 | Viewed by 5150

Abstract

Penconazole is a widely used fungicide in the UK; however, to date, there have been no peer-reviewed publications reporting human metabolism, excretion or biological monitoring data. The objectives of this study were to i) develop a robust analytical method, ii) determine biomarker levels in volunteers exposed to penconazole, and, finally, to iii) measure the metabolites in samples collected as part of a large investigation of rural residents’ exposure. An LC-MS/MS method was developed for penconazole and two oxidative metabolites. Three volunteers received a single oral dose of 0.03 mg/kg body weight and timed urine samples were collected and analysed. The volunteer study demonstrated that both penconazole-OH and penconazole-COOH are excreted in humans following an oral dose and are viable biomarkers. Excretion is rapid with a half-life of less than four hours. Mean recovery of the administered dose was 47% (range 33%–54%) in urine treated with glucuronidase to hydrolyse any conjugates. The results from the residents’ study showed that levels of penconazole-COOH in this population were low with >80% below the limit of detection. Future sampling strategies that include both end of exposure and next day urine samples, as well as contextual data about the route and time of exposure, are recommended. Full article

(This article belongs to the Collection Risk Assessment of Pesticide Exposure)

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642 KiB

Open AccessArticle

Assessing Potential Vulnerability and Response of Fish to Simulated Avian Predation after Exposure to Psychotropic Pharmaceuticals

by Melanie L. Hedgespeth, Per Anders Nilsson and Olof Berglund

Toxics 2016, 4(2), 9; https://doi.org/10.3390/toxics4020009 - 13 Apr 2016

Cited by 8 | Viewed by 5425

Abstract

Psychotropic pharmaceuticals present in the environment may impact organisms both directly and via interaction strengths with other organisms, including predators; therefore, this study examined the potential effects of pharmaceuticals on behavioral responses of fish to avian predators. Wild-caught juvenile perch (Perca fluviatilis) were assayed using a striking bird model after a seven-day exposure to psychotropic pharmaceuticals (the antidepressants fluoxetine or sertraline, or the β-blocker propranolol) under the hypotheses that exposure would increase vulnerability to avian predation via increasing the probability of predator encounter as well as degrading evasive behaviors upon encounter. None of the substances significantly affected swimming activity of the fish, nor did they increase vulnerability by affecting encounter probability or evasive endpoints compared to control treatments. Counter to our expectations, fish exposed to 100 μg/L fluoxetine (but no other concentrations or pharmaceuticals) were less likely to enter the open area of the arena, i.e., less likely to engage in risky behavior that could lead to predator encounters. Additionally, all fish exposed to environmentally relevant, low concentrations of sertraline (0.12 μg/L) and propranolol (0.1 μg/L) sought refuge after the simulated attack. Our unexpected results warrant further research as they have interesting implications on how these psychotropic pharmaceuticals may affect predator-prey interactions spanning the terrestrial-aquatic interface. Full article

(This article belongs to the Special Issue Toxic Effects of Pharmaceutical and Personal Care Products (PPCPs) on Non-Target Aquatic Organisms)

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Graphical abstract

192 KiB

Open AccessCommunication

Current Status of Air Toxics Management and Its Strategies for Controlling Emissions in Taiwan

by Wen-Tien Tsai

Toxics 2016, 4(2), 8; https://doi.org/10.3390/toxics4020008 - 12 Apr 2016

Cited by 13 | Viewed by 4589

Abstract

Since the 1970s, hazardous air pollutants (HAPs), so-called air toxics, have been of great concern because they can cause serious human health effects and have adverse effects on the environment. More noticeably, some of them are known to be human carcinogens. The objective of this paper is to investigate the regulatory systems and human health effects of air toxics which have been designated by the Taiwan government under the Air Pollution Control Act. These toxic air pollutants include acutely toxic gas (i.e., ammonia, chlorine, fluorides, hydrochloric acid, hydrogen cyanide, hydrogen sulfide, nitric acid, phosphoric acid and sulfuric acid), gas containing heavy metals, and carcinogenic chemicals (including formaldehyde, vinyl chloride, asbestos and matter containing asbestos, dioxins and furans, volatile organic compounds, polycyclic aromatic hydrocarbons, and polychlorinated biphenyls). In line with international concern about the carcinogenic risk and environmental persistence of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/PCDFs) and heavy metals in recent years, the current status in monitoring and reducing the emissions of PCDDs/PCDFs from stationary sources was analyzed as a case study in the present study. Furthermore, the control strategies for reducing emissions of air toxics from stationary sources in Taiwan were also addressed. Full article

(This article belongs to the Special Issue Air Toxics)

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Toxics, Volume 4, Issue 2 (June 2016) – 4 articles

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