Air-soil cycling of oxygenated, nitrated and parent polycyclic aromatic hydrocarbons in source and receptor areas

Polycyclic aromatic hydrocarbons (PAHs) and their oxygenated and nitrated derivatives, OPAHs and NPAHs, are semivolatile air pollutants which are distributed and cycling regionally. Subsequent to atmospheric deposition to and accumulation in soils they may re-volatilise, a secondary source which is understudied. We studied the direction of air-soil mass exchange fluxes of 12 OPAHs, 17 NPAHs, 25 PAHs and one alkylated PAH in two rural environments being influenced by the pollutant concentrations in soil and air, by season, and by land cover. The OPAHs and NPAHs in samples of topsoil, of ambient air particulate and gas phases and in the gas-phase equilibrated with soil were analysed by GC-APCI-MS/MS. The pollutants soil burdens show a pronounced seasonality, a winter maximum for NPAHs and PAHs and a summer maximum for OPAHs. One order of magnitude more OPAH and parent PAH are found stored in forest soil than in nearby grassland soil. Among a number of 3-4 ring PAHs, the OPAHs benzanthrone and 6H-benzo(c,d)pyren-6-one, and the NPAHs 1- and 2-nitronaphthalene, 9-nitrophenanthrene and 7-nitrobenz(a)anthracene are found to re-volatilise from soils at a rural background site in central Europe in summer. At a receptor site in northern Europe, net deposition of polycyclic aromatic compounds (PACs) prevails and re-volatilisation occurs only sporadic. Re-volatilisation of a number of PACs, including strong mutagens, from soils in summer and even in winter indicates that long-range atmospheric transport of primary PAC emissions from central Europe to receptor areas might be enhanced by secondary emissions from soils.

Novel flame retardants detected in marine plastic litter in coastal areas in Central Chile

Flame retardants (FRs) are released throughout the plastic life cycle, potentially impacting the environment, biodiversity, and human health. This study analyzed novel flame retardants (NFR) in marine plastic litter (MPL) from six coastal areas in central Chile in November 2017. Target chemicals (n = 19) were analyzed using ultrasonic extraction with hexane, gas chromatography, and mass spectrometry (GC-MS). From all nineteen NFRs analyzed, only ten (53 %) were routinely detected. BTBPE (1,2-bis(2,4,6-tribromophenoxy) ethane) showed the highest concentrations at the Bellavista site (618 to 424,000 pg g-1), and HBB (Hexabromobiphenyl), banned since 1970, was detected in Coliumo (2630 to 13,700 pg g-1). These results show emerging transport patterns and underscore the critical need for enhanced waste management practices for MPL in coastal regions to prevent adverse impacts on marine biodiversity.

Widespread Pesticide Distribution in the European Atmosphere Questions their Degradability in Air

Risk assessment of pesticide impacts on remote ecosystems makes use of model-estimated degradation in air. Recent studies suggest these degradation rates to be overestimated, questioning current pesticide regulation. Here, we investigated the concentrations of 76 pesticides in Europe at 29 rural, coastal, mountain, and polar sites during the agricultural application season. Overall, 58 pesticides were observed in the European atmosphere. Low spatial variation of 7 pesticides suggests continental-scale atmospheric dispersal. Based on concentrations in free tropospheric air and at Arctic sites, 22 pesticides were identified to be prone to long-range atmospheric transport, which included 15 substances approved for agricultural use in Europe and 7 banned ones. Comparison between concentrations at remote sites and those found at pesticide source areas suggests long atmospheric lifetimes of atrazine, cyprodinil, spiroxamine, tebuconazole, terbuthylazine, and thiacloprid. In general, our findings suggest that atmospheric transport and persistence of pesticides have been underestimated and that their risk assessment needs to be improved.

Plastic debris, persistent organic pollutants and their toxicity impacts in coastal areas in Central Chile

The chemical components of plastic wastes have made their disposal a major economic, social, and environmental problem worldwide. This study evaluated the acute toxicity and genotoxicity of marine plastic debris on the beaches of Concepción Bay, Central Chile, taken during three periods (spring, summer, and winter). An integrated approach was used, including chemical and toxicological data, using the Microtox® test with Vibrio fischeri and SOS chromotest with Escherichia coli and concentrations of polychlorinated biphenyls (PCBs), Organochlorine Pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs). The results presented here exclusively include the novel data obtained from the winter campaign, revealing high concentrations of PBDEs (238 ± 521 ng g-1). In addition, the genotoxicity and acute toxicity tests were sensitive for most of the samples studied. This investigation is the first attempt to analyse the toxicity of plastic debris in coastal areas along the Chilean coast.

Spatial and Temporal Trends of Persistent Organic Pollutants across Europe after 15 Years of MONET Passive Air Sampling

The Global Monitoring Plan of the Stockholm Convention on Persistent Organic Pollutants (POPs) was established to generate long-term data necessary for evaluating the effectiveness of regulatory measures at a global scale. After 15 years of passive air monitoring (2003-2019), MONET is the first network to produce sufficient data for the analysis of continuous long-term temporal trends of POPs in air across the entire European continent. This study reports long-term concentrations of 20 POPs monitored at 32 sites in 27 European countries. As of January 1, 2019, the concentration ranges (pg/m3) were 1.1-52.8 (∑6PCB), 0.3-8.5 (∑12dl-PCB), 0.007-0.175 (∑17PCDD/F), 0.02-2.2 (∑9PBDE), 0.4-24.7 (BDE 209), 0.5-247 (∑6DDT), 1.7-818 (∑4HCH), 15.8-74.7 (HCB), and 5.9-21.5 (PeCB). Temporal trends indicate that concentrations of most POPs have declined significantly over the past 15 years, with median annual decreases ranging from -8.0 to -11.5% (halving times of 6-8 years) for ∑6PCB, ∑17PCDD/F, HCB, PeCB, and ∑9PBDE. Furthermore, no statistically significant differences were observed in either the trends or the concentrations of specific POPs at sites in Western Europe (WEOG) compared to sites in Central and Eastern Europe (CEE), which suggests relatively uniform compound-specific distribution and removal at the continental scale.

Exposure of children and adolescents from Northeastern Slovenia to per- and polyfluoroalkyl substances

Per- and polyfluoroalkyl substances (PFAS) are of high concern for the environment, wildlife, and human health due to their persistence and potential to cause adverse health effects. Despite political measures to restrict the production and distribution of PFAS and to limit the exposure of populations, PFAS can be measured at commonly high detection frequencies in human samples. Thus, this pilot study aimed to determine the serum concentrations of PFPA, PFHpA, PFOA, PFNA, PFDA, PFUnDA, PFHxS, PFHpS, PFOS, PFHxA, PFDoDA, and PFBS in 113 girls and 112 boys (age 7-10 and 12-15) from Northeastern Slovenia - a rural area characterized by agricultural activities - and to identify potential sources of exposure using questionnaire data. PFAS were analysed by liquid chromatography coupled to mass spectrometry after phospholipid removal. 9 out of 12 analytes were detected at detection frequencies above 30%, with the highest geometric means (GM) being observed for PFOS (GM 1.9 ng/mL) > PFOA (GM 1.0 ng/mL) > PFHxS (GM 0.3 ng/mL) = PFNA (GM 0.3 ng/mL). We identified the participants' socio-economic status, age, sex, sampling region, public water supply, and the consumption of fish and seafood, cereals, and locally produced fruits, vegetables, and mushrooms as the predominant determinants of exposure. Furthermore, we compared our results with the serum and plasma concentrations reported for similar age groups in other studies and concluded that PFAS exposure in this highly agricultural area in Slovenia is notably low. This is the first study systematic HBM study of PFAS exposure in Slovenia, although it was conducted on a limited number of participants representative of rural and agricultural areas, it represents a good basis for upgrading the approach to a nationwide HBM study.

Human Exposure to Pesticides in Dust from Two Agricultural Sites in South Africa

Over the last decades, concern has arisen worldwide about the negative impacts of pesticides on the environment and human health. Exposure via dust ingestion is important for many chemicals but poorly characterized for pesticides, particularly in Africa. We investigated the spatial and temporal variations of 30 pesticides in dust and estimated the human exposure via dust ingestion, which was compared to inhalation and soil ingestion. Indoor dust samples were collected from thirty-eight households and two schools located in two agricultural regions in South Africa and were analyzed using high-performance liquid chromatography coupled to tandem mass spectrometry. We found 10 pesticides in dust, with chlorpyrifos, terbuthylazine, carbaryl, diazinon, carbendazim, and tebuconazole quantified in >50% of the samples. Over seven days, no significant temporal variations in the dust levels of individual pesticides were found. Significant spatial variations were observed for some pesticides, highlighting the importance of proximity to agricultural fields or of indoor pesticide use. For five out of the nineteen pesticides quantified in dust, air, or soil (i.e., carbendazim, chlorpyrifos, diazinon, diuron and propiconazole), human intake via dust ingestion was important (>10%) compared to inhalation or soil ingestion. Dust ingestion should therefore be considered in future human exposure assessment to pesticides.

Personal care product use and lifestyle affect phthalate and DINCH metabolite levels in teenagers and young adults

Humans are widely exposed to phthalates and their novel substitutes, and considering the negative health effects associated with some phthalates, it is crucial to understand population levels and exposure determinants. This study is focused on 300 urine samples from teenagers (aged 12-17) and 300 from young adults (aged 18-37) living in Czechia collected in 2019 and 2020 to assess 17 plasticizer metabolites as biomarkers of exposure. We identified widespread phthalate exposure in the study population. The diethyl phthalate metabolite monoethyl phthalate (MEP) and three di (2-ethylhexyl) phthalate metabolites were detected in the urine of >99% of study participants. The highest median concentrations were found for metabolites of low-molecular-weight (LMW) phthalates: mono-n-butyl phthalate (MnBP), monoisobutyl phthalate (MiBP) and MEP (60.7; 52.6 and 17.6 μg/L in young adults). 1,2-cyclohexanedicarboxylic acid diisononyl ester (DINCH) metabolites were present in 68.2% of the samples with a median of 1.24 μg/L for both cohorts. Concentrations of MnBP and MiBP were similar to other European populations, but 5-6 times higher than in populations in North America. We also observed large variability in phthalate exposures within the study population, with 2-3 orders of magnitude differences in urinary metabolites between high and low exposed individuals. The concentrations varied with season, gender, age, and lifestyle factors. A relationship was found between high levels of MEP and high overall use of personal care products (PCPs). Cluster analysis suggested that phthalate exposures depend on season and multiple lifestyle factors, like time spent indoors and use of PCPs, which combine to lead to the observed widespread presence of phthalate metabolites in both study populations. Participants who spent more time indoors, particularly noticeably during colder months, had higher levels of high-molecular weight phthalate metabolites, whereas participants with higher PCP use, particularly women, tended to have higher concentration of LMW phthalate metabolites.

Using large amounts of firefighting foams releases per- and polyfluoroalkyl substances (PFAS) into estuarine environments: A baseline study in Latin America

We analyzed per- and polyfluoroalkyl substances (PFAS) in aqueous film-forming foams (AFFFs) used to extinguish a major fire in a petrochemical terminal from the Port of Santos (Brazil). Eight AFFFs from seven known commercial brands and one unknown sample (AFFF-1 to AFFF-8) were evaluated. 17 PFAS were identified and quantified using high performance liquid chromatography (LC/MS). The concentrations of Σ17 PFAS in the AFFFs ranged from 500 to 9000 ng/g, with prevalence of short chain PFAS (~85 %), followed by long chain PFAS. Perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), included in the global treaty of the Stockholm Convention, were also detected. We estimated that at least 635.96 g of PFAS were introduced in the estuary, representing a massive input of these substances. This investigation reports the PFAS composition of AFFFs used in firefighting in the GRULAC Region (Group of Latin American and Caribbean countries).

Nitro- and oxy-PAHs in grassland soils from decade-long sampling in central Europe

Long-term exposure to polycyclic aromatic hydrocarbons (PAHs) and their nitrated (NPAHs) and oxygenated (OPAHs) derivatives can cause adverse health effects due to their carcinogenicity, mutagenicity and oxidative potential. The distribution of PAH derivatives in the terrestrial environment has hardly been studied, although several PAH derivatives are ubiquitous in air and long-lived in soil and water. We report the multi-annual variations in the concentrations of NPAHs, OPAHs and PAHs in soils sampled at a semi-urban (Mokrá, Czech Republic) and a regional background site (Košetice, Czech Republic) in central Europe. The concentrations of the Σ₁₈NPAHs and the Σ₁₁₊₂OPAHs and O-heterocycles were 0.31 ± 0.23 ng g^-1 and 4.03 ± 3.03 ng g^-1, respectively, in Košetice, while slightly higher concentrations of 0.54 ± 0.45 ng g^-1 and 5.91 ± 0.45 ng g^-1, respectively, were found in soil from Mokrá. Among the 5 NPAHs found in the soils, 1-nitropyrene and less so 6-nitrobenzo(a)pyrene were most abundant. The OPAHs were more evenly distributed. The ratios of the PAH derivatives to their parent PAHs in Košetice indicate that they were long-range transported to the background site. Our results show that several NPAHs and OPAHs are abundant in soil and that gas-particle partitioning is a major factor influencing the concentration of several semi-volatile NPAHs and OPAHs in the soils. Complete understanding of the long-term variations of NPAH and OPAH concentrations in soil is limited by the lack of kinetic data describing their formation and degradation.

Comparability of semivolatile organic compound concentrations from co-located active and passive air monitoring networks in Europe

Passive air sampling (PAS) has been used to monitor semivolatile organic compounds (SVOCs) for the past 20 years, but limitations and uncertainties persist in the derivation of effective sampling volumes, sampling rates, and concentrations. As a result, the comparability of atmospheric levels measured by PAS and concentrations measured by active air sampling (AAS) remains unclear. Long-term PAS data, without conversion into concentrations, provide temporal trends that are similar to, and consistent with, trends from AAS data. However, for more comprehensive environmental and human health assessments of SVOCs, it is also essential to harmonize and pool air concentration data from the major AAS and PAS monitoring networks in Europe. To address this need, we calculated and compared concentration data for 28 SVOCs (including organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and polycyclic aromatic hydrocarbons (PAHs)) at the six monitoring sites in Europe with 10 years of co-located AAS (EMEP) and PAS (MONET) data: Birkenes, Košetice, Pallas, Råö, Stórhöfði, and Zeppelin. Atmospheric SVOC concentrations were derived from PAS data using the two most common computation models. Long-term agreement between the AAS and PAS data was strong for most SVOCs and sites, with 79% of the median PAS-derived concentrations falling within a factor of 3 of their corresponding AAS concentrations. However, in both models it is necessary to set a sampler-dependent correction factor to prevent underestimation of concentrations for primarily particle-associated SVOCs. In contrast, the models overestimate concentrations at sites with wind speeds that consistently exceed 4 m s^-1. We present two recommendations that, if followed, allow MONET PAS to provide sufficiently accurate estimates of SVOC concentrations in air so that they can be deployed together with AAS in regional and global monitoring networks.

Toxicity to bronchial cells and endocrine disruptive potentials of indoor air and dust extracts and their association with multiple chemical classes

Pollution of indoor environment, where people spend much of their time, comprises complex mixtures of compounds with vastly understudied hazard potential. This study examined several important specific toxic effects and pollutant levels (177 compounds) of indoor samples (air gas phase, PM₁₀ and dust) from different microenvironments after two extractions with focus on their gas/particle/dust distribution and polarity. The endocrine disruptive (ED) potential was assessed by human cell-based in vitro bioassays addressing anti-/estrogenicity, anti-/androgenicity, aryl hydrocarbon, thyroid and peroxisome proliferator-activated receptor-mediated activities. Potential toxicity to respiratory tract tissue was assessed using human bronchial cell line. The toxicological analyses pointed out the relevance of both inhalation and ingestion exposure, with significant effects detected after exposure to extracts from all three studied matrices with distinct gas/particle distribution patterns. Chemical analyses document the high complexity of indoor pollutant mixtures with greatest levels of phthalates, their emerging alternatives, and PAHs in dust. Despite the detection of up to 108 chemicals, effects were explained only to low extent. This emphasizes data gaps regarding ED potencies of many detected abundant indoor contaminants, but also potential presence of other unidentified ED compounds. The omnipresent ED potentials in indoor environment rise concern regarding associated human health risk.

Seasonal variations in air concentrations of 27 organochlorine pesticides (OCPs) and 25 current-use pesticides (CUPs) across three agricultural areas of South Africa

For decades pesticides have been used in agriculture, however, the occurrence of legacy organochlorine pesticides (OCPs) and current-use pesticides (CUPs) is poorly understood in Africa. This study investigates air concentrations of OCPs and CUPs in three South African agricultural areas, their spatial/seasonal variations and mixture profiles. Between 2017 and 2018, 54 polyurethane foam-disks passive air-samplers (PUF-PAS) were positioned in three agricultural areas of the Western Cape, producing mainly apples, table grapes and wheat. Within areas, 25 CUPs were measured at two sites (farm and village), and 27 OCPs at one site (farm). Kruskal-Wallis tests investigated area differences in OCPs concentrations, and linear mixed-effect models studied differences in CUPs concentrations between areas, sites and sampling rounds. In total, 20 OCPs and 16 CUPs were detected. A median of 16 OCPs and 10 CUPs were detected per sample, making a total of 11 OCPs and 24 CUPs combinations. Eight OCPs (trans-chlordane, o,p'-/p,p'-dichlorodiphenyldichloroethylene (DDE)/dichlorodiphenyltrichloroethane (DDT), endosulfan sulfate, γ-hexachlorocyclohexane and mirex) and two CUPs (carbaryl and chlorpyrifos) were quantified in all samples. p,p'-DDE (median 0.14 ng/m³) and chlorpyrifos (median 0.70 ng/m³) showed the highest concentrations throughout the study. Several OCPs and CUPs showed different concentrations between areas and seasons, although CUPs concentrations did not differ between sites. OCPs ratios suggest ongoing chlordane use in the region, while DDT and endosulfan contamination result from past-use. Our study revealed spatial and seasonal variations of different OCPs and CUPs combinations detected in air. Further studies are needed to investigate the potential cumulative or synergistic risks of the detected pesticides.

Multicompartmental analysis of POPs and PAHs in Concepciόn Bay, central Chile: Part I - Levels and patterns after the 2010 tsunami

Persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs) were determined in abiotic samples from Concepción Bay in Central Chile. Samples were soxhlet extracted and injected in gas chromatography-mass spectrometry (GCMS). Polybrominated diphenyl ethers (PBDEs) showed the highest levels in air (3-1100 pg m^-3), in water (2-64 pg L^-1), in sediment, and soil (1-78 ng g^-1 (dw)). PAHs were also high in the air (1-6 ng m^-3), in water (1-7 ng L^-1), in sediment (90-300 ng g^-1 (dw)), and in soil (15-2300 ng g^-1 (dw)). The polychlorinated biphenyls (PCBs) and chlorinated pesticides were generally low and did not show clear trends along the water column, with exception of PAHs. New data are presented in this work to assess the health status of a relevant coastal area in central Chile.

Application of land use regression modelling to describe atmospheric levels of semivolatile organic compounds on a national scale

Despite the success of passive sampler-based monitoring networks in capturing global atmospheric distributions of semivolatile organic compounds (SVOCs), their limited spatial resolution remains a challenge. Adequate spatial coverage is necessary to better characterize concentration gradients, identify point sources, estimate human exposure, and evaluate the effectiveness of chemical regulations such as the Stockholm Convention on Persistent Organic Pollutants. Land use regression (LUR) modelling can be used to integrate land use characteristics and other predictor variables (industrial emissions, traffic intensity, demographics, etc.) to describe or predict the distribution of air concentrations at unmeasured locations across a region or country. While LUR models are frequently applied to data-rich conventional air pollutants such as particulate matter, ozone, and nitrogen oxides, they are rarely applied to SVOCs. The MONET passive air sampling network (RECETOX, Masaryk University) continuously measures atmospheric SVOC levels across Czechia in monthly intervals. Using monitoring data from 29 MONET sites over a two-year period (2015-2017) and a variety of predictor variables, we developed LUR models to describe atmospheric levels and identify sources of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and DDT across the country. Strong and statistically significant (R² > 0.6; p < 0.05) models were derived for PAH and PCB levels on a national scale. The PAH model retained three predictor variables - heating emissions represented by domestic fuel consumption, industrial PAH point sources, and the hill:valley index, a measure of site topography. The PCB model retained two predictor variables - site elevation, and secondary sources of PCBs represented by soil concentrations. These models were then applied to Czechia as a whole, highlighting the spatial variability of atmospheric SVOC levels, and providing a tool that can be used for further optimization of sampling network design, as well as evaluating potential human and environmental chemical exposures.

Occurrence of perfluoroalkyl substances (PFASs) in marine plastic litter from coastal areas of Central Chile

Perfluorinated alkyl substances (PFASs) were determined in marine plastic litter (MPL) on six beaches of central Chile. MPL was characterized physically and chemically, showing an abundance of macroplastic (size >2.5 cm). The polypropylene (PP) (47%) was the predominant polymer found. The Desembocadura beach, located at the mouth of the Biobio River, recorded the highest abundance of MPL (3.7 items m^-2). PFAS detected (n = 15/21) ranged from 279 to 1211 pg g^-1 and accounted for MeFOSE (46%) > PFHxS (14%) > PFPA (11%) > PFBS (6%) > PFOA (4%) and > PFOS (4%). Long-chain PFAS were prevalent, which can be metabolically degraded into PFOS (new POPs). This study i) highlights the need to further investigate the occurrence of chemicals in the MPL to reduce their impact on the environment; and ii) points out the need to improve future coastal management strategies for the elimination of solid waste along the coast of the country.

A comprehensive assessment of endocrine-disrupting chemicals in an Indian food basket: Levels, dietary intakes, and comparison with European data

Endocrine-disrupting chemicals (EDCs) in diet are a health concern and their monitoring in food has been introduced in the European Union. In developing countries, EDC dietary exposure data are scarce, especially from areas perceived as pollution hotspots, including industrialized countries like India. Several persistent organic pollutants (POPs) act as EDCs and pose a pressure to human health mainly through dietary exposure. In the present study, a range of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), dioxins and furans were measured in several food items collected from Indian urban (Delhi) and peri-urban (Dehradun) areas. Food basket contamination data were used to estimate EDC dietary exposure and compare it with that of the average European population estimated from available monitoring data. All the target contaminants were found in most food items, especially in dairies and meat products. OCPs were the main contributers to the measured EDC contamination. Food supplied to Delhi's markets had higher EDC contamination than that supplied to the peri-urban market in Dehradun. Despite lax compliance and control measures, Indian dietary exposure of OCPs and PBDEs were comparable with that of Europe and were lower for PCBs and dioxins. Higher meat consumption in Europe only partly explained this pattern which was driven also by the higher EDC residues in some European food items. A substantial part of endocrine disrupting potential in the diet derives from food and animal feeds internationally traded between developed and developing countries. With increasingly globalized food systems, internationally harmonized policies on EDC content in food can lead to better protection of health in both these contexts.

NPAHs and OPAHs in the atmosphere of two central European cities: Seasonality, urban-to-background gradients, cancer risks and gas-to-particle partitioning

Derivatives of polycyclic aromatic hydrocarbons (PAHs) such as nitrated- and oxygenated-PAHs (NPAHs and OPAHs) could be even more toxic and harmful for the environment and humans than PAHs. We assessed the spatial and seasonal variations of NPAHs and OPAHs atmospheric levels, their cancer risks and their gas-to-particle partitioning. To this end, about 250 samples of fine particulate matter (PM2.5) and 50 gaseous samples were collected in 2017 in central Europe in the cities of Brno and Ljubljana (two traffic and two urban background sites) as well as one rural site. The average particulate concentrations were ranging from below limit of quantification to 593 pg m-3 for Σ9NPAHs and from 1.64 to 4330 pg m-3 for Σ11OPAHs, with significantly higher concentrations in winter compared to summer. In winter, the particulate levels of NPAHs and OPAHs were higher at the traffic site compared to the urban background site in Brno while the opposite was found in Ljubljana. NPAHs and OPAHs particulate levels were influenced by the meteorological parameters and co-varied with several air pollutants. The significance of secondary formation on the occurrence of some NPAHs and OPAHs is indicated. In winter, 27-47% of samples collected at all sites were above the acceptable lifetime carcinogenic risk. The gas-particle partitioning of NPAHs and OPAHs was influenced by their physico-chemical properties, the season and the site-specific aerosol composition. Three NPAHs and five OPAHs had higher particulate mass fractions at the traffic site, suggesting they could be primarily emitted as particles from vehicle traffic and subsequently partitioning to the gas phase along air transport. This study underlines the importance of inclusion of the gas phase in addition to the particulate phase when assessing the atmospheric fate of polycyclic aromatic compounds and also when assessing the related health risk.

Temporal Trends of Persistent Organic Pollutants across Africa after a Decade of MONET Passive Air Sampling

The Global Monitoring Plan of the Stockholm Convention on Persistent Organic Pollutants (POPs) was established to generate long-term data necessary for evaluating the effectiveness of regulatory measures at a global scale. After a decade of passive air monitoring (2008-2019), MONET is the first network to produce sufficient data for the analysis of long-term temporal trends of POPs in the African atmosphere. This study reports concentrations of 20 POPs (aldrin, chlordane, chlordecone, DDT, dieldrin, endrin, endosulfan, HBCDD, HCB, HCHs, heptachlor, hexabromobiphenyl, mirex, PBDEs, PCBs, PCDDs, PCDFs, PeCB, PFOA, and PFOS) monitored in 9 countries (Congo, Ghana, Ethiopia, Kenya, Mali, Mauritius, Morocco, Nigeria, and Sudan). As of January 1, 2019, concentrations were in the following ranges (pg/m³): 0.5-37.7 (∑₆PCB), 0.006-0.724 (∑₁₇PCDD/F), 0.05-5.5 (∑₉PBDE), 0.6-11.3 (BDE 209), 0.1-1.8 (∑₃HBCDD), 1.8-138 (∑₆DDT), 0.1-24.3 (∑₃endosulfan), 0.6-14.6 (∑₄HCH), 9.1-26.4 (HCB), 13.8-18.2 (PeCB). Temporal trends indicate that concentrations of many POPs (PCBs, DDT, HCHs, endosulfan) have declined significantly over the past 10 years, though the rate was slow at some sites. Concentrations of other POPs such as PCDD/Fs and PBDEs have not changed significantly over the past decade and are in fact increasing at some sites, attributed to the prevalence of open burning of waste (particularly e-waste) across Africa. Modeled airflow back-trajectories suggest that the elevated concentrations at some sites are primarily due to sustained local emissions, while the low concentrations measured at Mt. Kenya represent the continental background level and are primarily influenced by long-range transport.

Three years of atmospheric concentrations of nitrated and oxygenated polycyclic aromatic hydrocarbons and oxygen heterocycles at a central European background site

Nitrated and oxygenated polycyclic aromatic hydrocarbons (NPAHs, OPAHs) are abundant in the atmosphere and contribute significantly to the health risk associated with inhalation of polluted air. Despite the health hazard they pose, NPAHs and OPAHs were rarely included in monitoring. The aim of this study is to provide the first multi-year temporal trends of the concentrations, composition pattern and fate of NPAHs and OPAHs in air from a site representative of background air quality conditions in central Europe. Samples were collected every second week at a rural background site in the Czech Republic during 2015-2017. Concentrations ranged from 1.3 to 160 pg m^-3 for Σ₁₇NPAHs, from 32 to 2600 pg m^-3 for Σ₁₀OPAHs and from 5.1 to 4300 pg m^-3 for Σ₂O-heterocycles. The average particulate mass fraction (θ) ranged from 0.01 ± 0.02 (2-nitronaphthalene) to 0.83 ± 0.22 (1-nitropyrene) for individual NPAHs and from <0.01 ± 0.01 (dibenzofuran) to 0.96 ± 0.08 (6H-benzo (c,d)pyren-6-one) for individual OPAHs and O-heterocycles. The multiyear variations showed downward trends for a number of targeted compounds. This suggests that on-going emission reductions of PAHs are effective also for co-emitted NPAHs and OPAHs.

Chlorinated and brominated persistent compounds in hard coral, soft coral, and parrotfish from remote Mascarene islands

Persistent halogenated compounds (PHC) are of concern for human and environmental health. Persistent Organic Pollutants (POPs) are regulated by international treaties, but alternative compounds such as novel brominated flame retardants (NBFRs) and Dechlorane Plus (DP) are not-yet they are increasingly used. There are no data on PHCs in coral reef biota from tropical islands in the western Indian Ocean (WIO). For this assessment, three hard coral genera, two soft coral genera, and ember parrotfish (Scarus rubroviolaceus) were collected from the remote Rodrigues, Agalega, and St. Brandon's Atoll (Republic of Mauritius) in the Mascarene Basin of the WIO. Five compounds - Pentabromotoluene (PBT), γ-HCH, p,p'-DDE, HCB, and BDE-47- were quantifiable in all samples. Hard coral consistently contained the lowest concentrations of PHCs, except for NBFRs. The presence of BDE-47 suggests long-range aerial transport. We quantified DP, currently a candidate POP, in coral reef biota. PBT was measured in all samples also suggests long-range transport. Because the hard coral, soft coral, and fish had differing concentrations and patterns of PHCs, future surveys should stratify sampling accordingly. Agalega and St. Brandon's Atoll can be considered as locations to monitor changes in background concentrations of pollutants due to their remoteness.

Qualitative assessment of 27 current-use pesticides in air at 20 sampling sites across Africa

Increasing use of current-use pesticides (CUPs) in Africa raises environmental and public health concerns. But there is a large uncertainty about their occurrence and the composition of pesticide mixtures on this continent. This paper investigates the presence of 27 CUPs in air across 20 sampling sites in Africa. 166 passive air samples, consisting of polyurethane foam (PUF), were collected in 12 African countries between 2010 and 2018. Samples were extracted with methanol and analyzed via high-performance liquid chromatography coupled with tandem mass spectrometry. The detection frequencies of CUPs per site were compared to land use patterns and sampling years, while their similarities were assessed using hierarchical cluster analysis. Overall, 24 CUPs were detected at least once. In 93% of all samples, at least one CUP was detected, while 78% of the samples had mixtures of two or more CUPs (median 3, interquartile range 5). Atrazine and chlorpyrifos were detected in 19 out of 20 sampling sites. Carbaryl, metazachlor, simazine, tebuconazole and terbuthylazine had the highest detection frequencies at sampling sites dominated by croplands. Across all the sampling years, 16 CUPs were present. Seven CUPs were newly detected from 2016 onwards (azinfos-methyl, dimetachlor, chlorsulfuron, chlortoluron, isoproturon, prochloraz and pyrazon), while metamitron was only present before 2012. Sites within a radius of about 200 km showed similarities in detected CUP mixtures across all samples. Our results show the presence of CUP mixtures across multiple agricultural and urban locations in Africa which requires further investigation of related environmental and human health risks.

Polybrominated diphenyl ethers in plastic waste of electrical and electronic equipment: a case study in Belarus

Plastic waste of electrical and electronic equipment (WEEE) can contain polybrominated diphenyl ethers (PBDEs) that have been used as fire retardants for a long time. PBDEs were listed in the Stockholm Convention as persistent organic pollutants, so PBDE-containing plastic waste should be separated and disposed of in an ecologically sound manner. In the article, the results of bromine and PBDE content in plastic samples of WEEE collected in Belarus are presented. The screening method for bromine identification and HRGC/HRMS for PBDE identification were applied. It is shown that bromine is present in 43% of the 111 studied samples. Most often, Br-containing plastic was found in CRT monitor, CRT TVs and LCD monitor (about 50%), printers (35%), and LCD TVs (25%). PBDEs were revealed in 12 Br-containing samples, representing TVs, monitors, and printers. The sum of ∑10PBDEs varied from 6.6 to 21,000 μg/kg. BDE-209 dominated in 9 samples (75% of cases); BDE-183, in two; and BDE-47 and BDE-99, in one sample. Based on the low content of PBDEs in the plastic, year of equipment production, and year of restriction of PBDEs applied in the countries-manufacturers, it was concluded that the presence of PBDEs in plastic is a consequence of contaminated waste recycling. Despite the relatively low concentrations of PBDEs (below the limit values established by the Stockholm and Basel conventions for POP wastes), further research is necessary with an extension of the list of analyzed types of equipment and identification of other brominated flame retardants.

Marine plastic debris in Central Chile: Characterization and abundance of macroplastics and burden of persistent organic pollutants (POPs)

In this study, we characterized plastic debris (PD) found on beaches from Concepción Bay in central Chile during spring 2017 and summer 2018. The identification of polymers was carried out using FT-IR. Persistent organic pollutants (POPs) were extracted with hexane using an ultrasonic bath and further quantified through GC-MS. The highest abundance of PD was obtained during the summer (4.1 ± 3.7 items/m²), with the most common size range between 2.5 and 10 cm (42%) and the most frequent shape were plastic fragments (44%). FT-IR analysis showed that polypropylene was the most recurrent plastic polymer found. The ∑10PBDEs ranged from 2.1 to 1300 ng/g in spring 2017 and 392 to 3177 ng/g in summer 2018. ∑7PCBs ranged from 0.9 to 93 ng/g during the spring 2017 and 0.3 to 4.5 ng/g for summer 2018. This study is the first with information on POPs occurrence in the plastic debris of central Chile.

Persistent organic pollutants sorbed in plastic resin pellet - "Nurdles" from coastal areas of Central Chile

Plastic resin pellets were collected from coastal areas (n = 7) of central Chile. Pellets were analyzed using Fourier-transform infrared spectroscopy for polymer identification and gas chromatography-mass spectrometry for Persistent Organic Pollutants (POPs) determination. Screened compounds were PBDEs (n = 10), PCBs (n = 7), and OCPs (n = 13). Pellets were only found at Lenga Beach (San Vicente Bay), which is likely influenced by the presence of industrial activities in the surrounding coastal area. The diameter of the pellets was 4.0 ± 0.6 cm (n = 370), the color varied from white (32%) to yellowing (68%), and the most prevalent polymer identified was high-density polyethylene (99%). POPs concentrations (ng/g-pellet) ranged from 10 to 133 for Ʃ10PBDEs, from 3 to 60 for Ʃ7PCBs and between 0.1 and 7 for DDTs. Levels of POPs are consistent with other investigations around the world and highlight the sorbtion capacity of plastics resin pellets, and consequently transport of POPs into coastal environments.

Multiyear levels of PCDD/Fs, dl-PCBs and PAHs in background air in central Europe and implications for deposition

This study presents four years ambient monitoring data of seventeen 2,3,7,8-chlorine substituted polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs), twelve dioxin-like polychlorinated biphenyls (dl-PCBs) and sixteen polycyclic aromatic hydrocarbons (PAHs) designed by the US EPA at a background site in central Europe during 2011-2014. The concentrations expressed as toxic equivalents (TEQs) using the WHO₂₀₀₅-scheme for PCDD/Fs (0.2 fg m^-3-61.1 fg m^-3) were higher than for dl-PCBs (0.01 fg m^-3-2.9 fg m^-3), while the opposite was found in terms of mass concentrations. ΣPAHs ranged from 0.20 ng m^-3 to 134 ng m^-3. The mass concentration profile of PCDD/Fs, dl-PCBs and PAHs was similar throughout the four years. PCDD/Fs and PAHs concentrations were dominated by primary sources peaking in winter, while those of dl-PCBs were controlled by secondary sources characterized by a spring-summer peak. During 2011-2014, no significant decrease in the atmospheric levels of ΣPCDD/Fs was observed. On the other hand, the concentrations of Σdl-PCBs and ΣPAHs were decreasing, with halving times of 5.7 and 2.7 years, respectively. We estimated that 422 pg m^-2 year^-1-567 pg m^-2 year^-1 TEQ PCDD/Fs and 3.48 pg m^-2 year^-1-15.8 pg m^-2 year^-1 TEQ dl-PCBs were transferred from the air to the ground surfaces via dry particulate deposition during 2011-2014.

Fast Formation of Nitro-PAHs in the Marine Atmosphere Constrained in a Regional-Scale Lagrangian Field Experiment

Polycyclic aromatic hydrocarbons (PAHs) and some of their nitrated derivatives, NPAHs, are seemingly ubiquitous in the atmospheric environment. Atmospheric lifetimes may nevertheless vary within a wide range, and be as short as a few hours. The sources and sinks of NPAH in the atmosphere are not well understood. With a Lagrangian field experiment and modeling, we studied the conversion of the semivolatile PAHs fluoranthene and pyrene into the 2-nitro derivatives 2-nitrofluoranthene and 2-nitropyrene in a cloud-free marine atmosphere on the time scale of hours to 1 day between a coastal and an island site. Chemistry and transport during several episodes was simulated by a Lagrangian box model i.e., a box model coupled to a Lagrangian particle dispersion model, FLEXPART-WRF. It is found that the chemical kinetic data do capture photochemical degradation of the 4-ring PAHs under ambient conditions on the time scale of hours to 1 day, while the production of the corresponding NPAH, which sustained 2-nitrofluoranthene/fluoranthene and 2-nitropyrene/pyrene yields of (3.7 ± 0.2) and (1.5 ± 0.1)%, respectively, is by far underestimated. Predicted levels of NPAH come close to observed ones, when kinetic data describing the reactivity of the OH-adduct were explored by means of theoretically based estimates. Predictions are also underestimated by 1-2 orders of magnitude, when NPAH/PAH yields reported from laboratory experiments conducted under high NO_x conditions are adopted for the simulations. It is concluded that NPAH sources effective under low NO_x conditions, are largely underestimated.

Bulk atmospheric deposition of persistent organic pollutants and polycyclic aromatic hydrocarbons in Central Europe

Polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) are ubiquitous and toxic contaminants. Their atmospheric deposition fluxes on the regional scale were quantified based on simultaneous sampling during 1 to 5 years at 1 to 6 background/rural sites in the Czech Republic and Austria. The samples were extracted and analysed by means of gas chromatography coupled to mass spectrometry. For all seasons and sites, total deposition fluxes for Σ₁₅PAHs ranged 23-1100 ng m^-2 d^-1, while those for Σ6PCBs and Σ12OCPs ranged 64-4400 and 410-7800 pg m^-2 d^-1, respectively. Fluoranthene and pyrene were the main contributors to the PAH deposition fluxes, accounting on average for 19% each, while deposition fluxes of PCBs and OCPs were dominated by PCB153 (26%) and γ-hexachlorobenzene (30%), respectively. The highest deposition flux of Σ₁₅PAHs was generally found in spring, while no seasonality was found for PCB deposition. For deposition fluxes for Σ₁₂OCPs, no clear spatial trend was found, confirming the perception of long-lived regional pollutants. Although most OCPs and PCBs hardly partition to the particulate phase in ambient air, on average, 42% of their deposition fluxes were found on filters, confirming the perception that particle deposition is more efficient than dry gaseous deposition. Due to methodological constraints, fluxes derived from bulk deposition samplers should be understood as lower estimates, in particular with regard to those substances which in ambient aerosols mostly partition to the particulate phase.

Comparability of long-term temporal trends of POPs from co-located active and passive air monitoring networks in Europe

The comparability of data from active (ACT) and passive sampling (PAS) of persistent organic pollutants (POPs) in air is hindered by uncertainties related to the derivation of sampling rates and concentrations, as well as differences in the duration, volume and frequency of sampling. Although data from ACT have been used extensively in short-term PAS calibration studies, no attempts have been made to evaluate the comparability of long-term trends calculated from PAS to established ACT trends. This is crucial, as continuous long-term ACT is unfeasible in most regions of the world. To address these challenges, we calculated and compared trends for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) at the six sites in Europe with at least 5 years of co-located ACT and PAS data (2012-2016): Birkenes, Košetice, Pallas, Råö, Stórhöfði and Zeppelin. Strong agreement of ACT and PAS trends was observed for most OCPs and PCBs. Apart from two PCBs at Stórhöfði, all pairs of ACT and PAS trends followed the same direction. However, differences in the magnitude, significance and confidence intervals of their slopes were observed for some compounds and were primarily attributed to the short duration of the PAS time series. Despite some limitations, our results suggest that the comparability of ACT and PAS POP trends will continue to improve with additional years of data. This study confirms the suitability of PAS for the calculation of long-term POP trends in air, and highlights the importance of continuous sampling at established monitoring sites with consistent analytical methods.

Presence and characterization of microplastics in fish of commercial importance from the Biobío region in central Chile

In this study we have identified and characterized microplastic particles (MPs) found in six fish species of commercial importance in central Chile. The fish species belong to different trophic levels and were obtained from the oceanic and coastal habitats. To analyze MPs, the fish gastrointestinal content was extracted, analyzed and characterized using a microscopy equipped with Fourier-transform infrared spectroscopy (FT-IR). The MPs found in fish samples were mainly constituted by red microfibers (70-100%) with sizes ranging between 176 and 2842 μm. Polyester, polyethylene (PE) and polyethylene terephthalate (PET) were identified as the prevalent polymers detected. The coastal species showed the presence of microfibers with a higher size and abundance (71%) compared to oceanic species (29%), suggesting there is a greater exposure risk. These findings are consistent with results found in other investigations worldwide. However, further research is still needed to accurately establish the potential exposure risk for the public consuming these fish and the impact of MPs in the Chilean fishery activities.

Characterizing Spatial Diversity of Passive Sampling Sites for Measuring Levels and Trends of Semivolatile Organic Chemicals

Passive air sampling of semivolatile organic compounds (SVOCs) is a relatively inexpensive method that facilitates extensive campaigns with numerous sampling sites. An important question in the design of passive-sampling networks concerns the number and location of samplers. We investigate this question with the example of 17 SVOCs sampled at 14 background sites across the Czech Republic. More than 200 time series (length 5-11 years) were used to characterize SVOC levels and trends in air between 2003 and 2015. Six polychlorinated biphenyls (PCBs), 6 polyaromatic hydrocarbons (PAHs), and 5 organochlorine pesticides (OCPs) at 14 sites were assessed using data from the MONET passive sampling network. Significant decreases were found for most PCBs and OCPs whereas hexachlorobenzene (HCB) and most PAHs showed (mostly insignificant) increases. Spatial variability was rather low for PCBs and OCPs except for dichlorodiphenyltrichloroethane (DDT) and rather high for PAHs. The variability of the SVOC levels and trends depends on characteristics of the sites including their remoteness, landscape, population, and pollution sources. The sites can be grouped in distinct clusters, which helps to identify similar and, thereby, potentially redundant sites. This information is useful when monitoring networks need to be optimized regarding the location and number of sites.

Contamination Profile of DDTs in the Shark Somniosus microcephalus from Greenland Seawaters

DDT isomers were detected in all the liver and muscle samples of Greenland sharks Somniosus microcephalus (n = 15) caught in Greenland seawaters. The mean concentrations of ΣDDTs (sum of o,p' and p,p' DDT, DDD, and DDE isomers) were 1094 ± 818 ng/g lipid weight (lw) in the muscle and 761 ± 416 ng/g lw in the liver. The p,p'-DDE accounted for 48% ± 41% and 53% ± 54% of the total DDT residue in the white muscle and liver, respectively. The lipid content was 48% ± 10% in the muscle and 43% ± 17% in the liver. Female sharks showed the highest concentrations of ΣDDTs. The youngest shark showed higher concentrations of ΣDDTs in the liver than the older sharks. To our knowledge, this is one of the few investigations on DDT levels in S. microcephalus where concentrations were correlated to lipid content and sex/size.

Spatial gradients of polycyclic aromatic hydrocarbons (PAHs) in air, atmospheric deposition, and surface water of the Ganges River basin

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous semi-volatile organic pollutants. Their environmental occurrence is of global concern as some of them are carcinogens, mutagens, and teratogens. In this study, concentrations and distributions of 16 priority PAHs (∑PAHs) were measured in air, atmospheric deposition, and surface water at various locations in Himalayan, Middle, and Lower Reaches of the Ganges River, covering a spatial transect of 2500km, during two seasons (pre-monsoon and monsoon). The concentration of ∑PAHs ranged between 2.2 and 182.2ngm^-3 in air, between 186 and 8810ngm^-2day^-1 in atmospheric deposition, and between 0.05 and 65.9ngL^-1 in surface water. Air concentrations were strongly correlated with human population density. In the Middle and Lower Reaches of the Ganges River, atmospheric PAHs were mainly attributed to fossil fuel combustion sources. In the Himalayan Reach the influence of forest fire or biomass combustion was evident during the dry pre-monsoon season. Seasonality in concentrations of PAHs in river water was evident in the Himalayan Reach of the river, as a probable consequence of climate-modulated secondary source intensity (i.e. releases from glacier melting). Seasonality faded in the Middle and Lower Reaches of the Ganges where water contamination is expected to mainly reflect anthropogenic primary sources. Ambient air concentrations were used to calculate the probabilistic incremental lifetime cancer risk (ILCR). It was expectedly found to be higher in the Middle and Lower Reaches compared to the Himalayan Reach. The strong correlation between population density and air concentrations suggests population density may be used as a surrogate variable to assess human health risk in data-sparse regions such as the Ganges River basin.

Bioindication of PBDEs and PCBs by native and transplanted moss Pleurozium schreberi

PBDEs and PCBs are toxic, persistent organic pollutants (POPs), and the use of PCBs is forbidden, but they are still present in many environments and biota. 90-day assays were conducted with the moss Pleurozium schreberi transplanted from an uncontaminated control site to ten sites (rural and urban) selected in one of the most polluted regions of Upper Silesia in Poland. Native P. schreberi mosses were collected from the same ten polluted sites. Concentrations of PBDEs (28, 47, 66, 85, 99, 100, 153, 154, 183 and 209) and PCBs (28, 52, 101, 118, 138, 153, 180) were determined in all native and transplanted P. schreberi from all sites. Native P. schreberi contained the highest ΣPBDE and ΣPCB levels (63.6ngg^-1 and 4.47pgg^-1, respectively) when collected in the vicinity of a steel smelter. After 90 days of the experiment native and transplanted P. schreberi contained the highest concentrations of the same BDE 209 congener (88-91% of total PBDEs in the native mosses and 85-90% of the total PBDE burden in the transplants). The native and transplanted mosses from the industrial sites after 90 days of exposure contained significantly higher concentrations of all the examined PBDE and PCB congeners (except for 153 and 180) than mosses from rural sites. PBDE and PCB values were higher in native than in transplanted mosses after 90 days of exposure in both rural and industrial sites.

Passive Air Samplers As a Tool for Assessing Long-Term Trends in Atmospheric Concentrations of Semivolatile Organic Compounds

Many attempts have been made to quantify the relationship between the amount of persistent organic pollutants sequestered by passive air sampling devices and their actual concentrations in ambient air. However, this information may not be necessary for some applications. In this study, two sets of 30 ten-year-long time series of simultaneous passive and high-volume active air sampling carried out at the Košetice observatory in the Czech Republic were used for a comparison of temporal trends. Fifteen polyaromatic hydrocarbons, seven polychlorinated biphenyls and eight organochlorine pesticides were investigated. In most cases, a good agreement was observed between the trends derived from passive and active monitoring with the exception of several compounds obviously affected by sampling artifacts. Two sampling artifacts were observed: breakthrough of high-volume sampler filters for penta- and hexachlorobenzene and semiquantitative values for PAHs with a high molecular weight. It has been suggested before that annually aggregated results of passive air monitoring may be used directly for the assessment of the long-term behavior of these compounds. The extensive set of long-term data used in this study allowed us to confirm this finding and to demonstrate that it is also possible to derive temporal trends and the compounds' half-lives in air from the passive-sampling time series.

Assessment of seasonal variations in persistent organic pollutants across the region of Tuscany using passive air samplers

Concentrations of persistent organic pollutants (POPs) were measured for an entire year in the region of Tuscany, Italy. Passive air samplers consisting of polyurethane foam (PUF) disks were deployed over four sampling periods of 3-5 months from April 2008 to July 2009 in urban (n = 6) and rural (n = 4) sites. The aim of the study was to characterize the spatial and seasonal variations in selected POPs. The POP concentrations (pg m^-3) in the air were dominated by dichlorodiphenyltrichloroethane and metabolites (DDTs) and polychlorinated biphenyls (∑₇PCBs). DDTs, and ∑₇PCBs showed a clear decreasing urban > rural gradient. The concentrations of DDTs and PCBs were up to 10 and 6 times higher, respectively, in urban sites than in rural sites. ∑₇PCBs showed a significant correlation with the urbanized areas located <5 km around the sampling sites. For hexachlorocyclohexanes (HCHs), α-HCH concentrations were similar at both sampling sites and were found to be quite uniform during the four sampling periods. Seasonal fluctuations were observed for DDTs, and ∑₇PCBs, with the highest concentrations observed during period 4 (summer-spring); this is most likely due to a temperature-driven re-emission from local sources. These findings were also supported by an air back trajectory analysis in the study area. This study contributes new information about POP levels in the Italian atmosphere and demonstrates the feasibility of using PUF disks to simultaneously assess seasonal concentrations at different sampling sites.

Passive air sampling of persistent organic pollutants (POPs) and emerging compounds in Kolkata megacity and rural mangrove wetland Sundarban in India: An approach to regional monitoring

Polyurethane foam (PUF) disk passive air samplers were deployed concurrently at five sites across Kolkata megacity and the rural mangrove wetland of Sundarban (UNESCO World Heritage Site) between January-March in 2014. Samples were analyzed for hexachlorocyclohexanes (HCHs), dichlorodiphenyltricholoroethanes (DDTs), polychlorinated biphenyls (PCBs) and, polybrominated diphenyl ethers (PBDEs) using gas chromatography and mass spectrometry (GC-MS). Derived air concentrations (pg/m³) for Kolkata ranged: for ∑α- and γ-HCH between 70 and 207 (114 ± 62), ∑₆DDTs: 127-216 (161 ± 36), ∑₇PCBs: 53-213 (141 ± 64), and ∑₁₀PBDEs: 0.30-23 (11 ± 9). Low values for all the studied POPs were recorded in the remote area of the Sundarban site (with the exception of DDTs: o,p'-DDT and p,p'-DDT), where ∑₄DDTs was 161 ± 36. In particular, the site of Ballygunge, located in the southern part of Kolkata, showed the highest level of all the metabolites/congeners of POPs, suggesting a potential hot spot of usage and emissions. From HCHs, α-/γ-HCH isomers ratio was low (0.67-1.96) indicating a possible sporadic source of lindane. γ-HCH dominated the HCH signal (at 3 sites) reflecting wide spread use of lindane both in Kolkata and the Sundarban region; however, isomeric composition in Kolkata also suggests potential technical HCHs use. Among DDT metabolites, both o,p'-DDT and p,p'-DDT shared the dominant percentages accounting for ∼26-46% of total DDTs followed by p,p'-DDE (∼12-19%). The PCB congener profile was dominated by tri- and tetra-Cl at the southern and eastern part of Kolkata. These results are one of the few contributions that reports air concentrations of POPs, concurrently, at urban and remote villages in India. These data are useful to assess atmospheric pollution levels and to motivate local and regional authorities to better understand the potential human exposure risk associated to urban areas in India.

Tracking polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in sediments and soils from the southwest of Buenos Aires Province, Argentina (South eastern part of the GRULAC region)

PCBs and PBDEs (7 and 10 congeners, respectively) were analyzed in four coastal surface sediments collected from the northern shore of Bahía Blanca estuary and in nine soils from different locations of Bahía Blanca city and the surrounding region (Southwest of Buenos Aires Province, Argentina). Sediment samples showed PCBs_(Σ7) concentrations ranged from 0.61 to 17.6ngg^-1 (dry weight=dw) and PBDEs_(Σ10) from 0.16 to 2.02ngg^-1 dw, whereas in soil samples ranged from 0.04 to 1.67ngg^-1 dw for PCBs_(Σ7) and 0.04 to 10.7ngg^-1 dw for PBDEs_(Σ10). The highest concentrations of both chemicals were detected in the urban and industrial/port areas showing a dominance of the higher chlorinated PCB congeners: in sediments for PCB-180 (56±33%) and PCB-153 (11±6%); and in soils for PCB-138 (23±3%), PCB-153 (22±2%) and PCB-180 (18±7%). In contrast, lower chlorinated PCB congeners were predominant at more distant sites; in sediments for congeners PCB-28 (33±4%) and PCB-52 (14.5±0.2%); and in soils PCB-28 (56±14%) and PCB-52 (33±19%). PBDE-209 (high brominated PBDE) showed the highest relative abundance in both sample types i.e., sediment (94±7%) and soil (80±12%). These findings can be considered lower or similar when compared with other sites of the world, and are likely associated with anthropogenic activities in their surrounding area, which has experienced a fast industrial growth in the last decade. This is the first investigation of PBDEs levels in the whole study area and of PCBs in soils from the Bahía Blanca city and surrounding region. This article provides new and useful information on POP levels in the South eastern part of the GRULAC region.

Distribution of legacy and emerging semivolatile organic compounds in five indoor matrices in a residential environment

Seven types of indoor samples, covering five indoor matrices, were collected in a residential room, and analyzed for five classes of semivolatile organic compounds (SVOCs). The goal was to improve the understanding of the relationship between indoor air, surface films and dust, based on differences in sources, physicochemical properties, and indoor environmental characteristics. Comparisons of the five matrices (gas- and particle-phase air, floor dust, surface dust/films and window films) demonstrated that within our test room a semi-quantitative measurement of the SVOC distributions and concentrations could be obtained by air, and composite dust or furniture surface wipes. Dust concentrations varied within the room, and spot samples were not necessarily representative of the average room conditions. Polyurethane foam passive air samplers (PUF-PAS) successfully quantified the total air concentrations of the studied SVOC compound groups, as indoor air concentrations were dominated by gas-phase compounds, however air concentrations of individual particle-bound compounds had higher uncertainty. Measured concentrations of dust/surfaces could be used to estimate air concentrations of legacy SVOCs, demonstrating equilibrium in the room. However, air concentrations of current-use compounds (flame retardants, polycyclic aromatic hydrocarbons (PAHs)) could not be estimated from dust/surface concentrations, demonstrating the influence of ongoing primary emissions and non-equilibrium status in the room.

Diurnal Variations of Air-Soil Exchange of Semivolatile Organic Compounds (PAHs, PCBs, OCPs, and PBDEs) in a Central European Receptor Area

Concentrations of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs) in air and soil, their fugacities, and the experimental soil-air partitioning coefficient (KSA) were determined at two background sites in the Gt. Hungarian Plain in August 2013. The concentrations of the semivolatile organic compounds (SOCs) in the soil were not correlated with the organic carbon content but with two indirect parameters of mineralization and aromaticity, suggesting that soil organic matter quality is an important parameter affecting the sorption of SOCs onto soils. Predictions based on the assumption that absorption is the dominant process were in good agreement with the measurements for PAHs, OCPs, and the low chlorinated PCBs. In general, soils were found to be a source of PAHs, high chlorinated PCBs, the majority of OCPs and PBDEs, and a sink for the low chlorinated PCBs and γ-hexachlorocyclohexane. Diurnal variations in the direction of the soil-air exchange were found for two compounds (i.e., pentachlorobenzene and p,p'-dichlorodiphenyldichloroethane), with volatilization during the day and deposition in the night. The concentrations of most SOCs in the near-ground atmosphere were dominated by revolatilization from the soil.

Melting Himalayan glaciers contaminated by legacy atmospheric depositions are important sources of PCBs and high-molecular-weight PAHs for the Ganges floodplain during dry periods

Melting glaciers are natural redistributors of legacy airborne pollutants, affecting exposure of pristine proglacial environments. Our data shows that melting Himalayan glaciers can be major contributors of polychlorinated biphenyls (PCBs) and high-molecular-weight polycyclic aromatic hydrocarbons (PAHs) for surface water in the Gangetic Plain during the dry season. Glacial emissions can exceed in some cases inputs from diffuse sources within the catchment. We analyzed air, deposition and river water in several sections along the Ganges River and its major headwaters. The predominant glacial origin of these contaminants in the Himalayan reach was demonstrated using air-water fugacity ratios and mass balance analysis. The proportion of meltwater emissions compared to pollutant discharge at downstream sections in the central part of the Gangetic Plain was between 2 and 200%. By remobilizing legacy pollutants from melting glaciers, climate change can enhance exposure levels over large and already heavily impacted regions of Northern India.

Air and seawater pollution and air-sea gas exchange of persistent toxic substances in the Aegean Sea: spatial trends of PAHs, PCBs, OCPs and PBDEs

Near-ground air (26 substances) and surface seawater (55 substances) concentrations of persistent toxic substances (PTS) were determined in July 2012 in a coordinated and coherent way around the Aegean Sea based on passive air (10 sites in 5 areas) and water (4 sites in 2 areas) sampling. The direction of air-sea exchange was determined for 18 PTS. Identical samplers were deployed at all sites and were analysed at one laboratory. hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs) as well as dichlorodiphenyltrichloroethane (DDT) and its degradation products are evenly distributed in the air of the whole region. Air concentrations of p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) and o,p'-DDT and seawater concentrations of p,p'-DDE and p,p'-DDD were elevated in Thermaikos Gulf, northwestern Aegean Sea. The polychlorinated biphenyl (PCB) congener pattern in air is identical throughout the region, while polybrominated diphenylether (PBDE)patterns are obviously dissimilar between Greece and Turkey. Various pollutants, polycyclic aromatic hydrocarbons (PAHs), PCBs, DDE, and penta- and hexachlorobenzene are found close to phase equilibrium or net-volatilisational (upward flux), similarly at a remote site (on Crete) and in the more polluted Thermaikos Gulf. The results suggest that effective passive air sampling volumes may not be representative across sites when PAHs significantly partitioning to the particulate phase are included.

Polybrominated Diphenyl Ethers (PBDEs) in Concepción Bay, central Chile after the 2010 Tsunami

PBDEs (10 congeners) were analyzed using GC-MS in superficial sediments and organisms of the Concepción Bay after the 2010 Tsunami. From all congeners analyzed PBDE-47, -99, -100 and -209 were the most frequently detected. Concentrations (ngg(-1) d.w.) in sediments for ΣPBDE-47, -99, -100 were low (0.02-0.09). However, PBDE-209 showed significantly higher values ∼20ngg(-1) d.w. This result were ∼10 times lower than those reported in a previous study of the 2010 Tsunami. The high result might be influenced by the massive urban debris dragged by the 2010 Tsunami. In organisms, concentrations of PBDE-47, -99, -100 (∼0.4ngg(-1) d.w.) were higher than those found in sediments (∼0.04ngg(-1) d.w.). Differences in PBDE pattern were also observed between different levels of the trophic food chain (primary and secondary consumers). This is the first attempt to assess the current status of Concepción Bay after the 2010 Tsunami.

Evaluation and guidelines for using polyurethane foam (PUF) passive air samplers in double-dome chambers to assess semi-volatile organic compounds (SVOCs) in non-industrial indoor environments

Indoor air pollution has been recognized as an important risk factor for human health, especially in areas where people tend to spend most of their time indoors. Many semi-volatile organic compounds (SVOCs) have primarily indoor sources and are present in orders of magnitude higher concentrations indoors than outdoors. Despite this, awareness of SVOCs in indoor air and assessment of the link between indoor concentrations and human health have lagged behind those of outdoor air. This is partially related to challenges associated with indoor sampling of SVOCs. Passive air samplers (PASs), which are widely accepted in established outdoor air monitoring networks, have been used to fill the knowledge gaps on indoor SVOCs distribution. However, their applicability for indoor environments and the assessment of human health risks lack sufficient experimental data. To address this issue, we performed an indoor calibration study of polyurethane foam (PUF) PAS deployed in a double-dome chamber, covering both legacy and new SVOC classes. PUF-PAS and a continuous low-volume active air sampler (AAS) were co-deployed for a calibration period of twelve weeks. Based on the results from this evaluation, PUF-PAS in a double-bowl chamber is recommended for indoor sampling and health risk assessment of gas phase SVOCs, including novel brominated flame retardants (nBFR) providing sufficient exposure time is applied. Data for particle associated SVOCs suffered from significant uncertainties caused by low level of detection and low precision in this study. A more open chamber design for indoor studies may allow for higher sampling rates (RS) and better performance for the particle associated SVOCs.

Outdoor passive air monitoring of semi volatile organic compounds (SVOCs): a critical evaluation of performance and limitations of polyurethane foam (PUF) disks

The most commonly used passive air sampler (PAS) (i.e. polyurethane foam (PUF) disk) is cheap, versatile, and capable of accumulating compounds present both in gas and particle phases. Its performance for particle associated compounds is however disputable. In this study, twelve sets of triplicate PUF-PAS were deployed outdoors for exposure periods of 1-12 weeks together with continuously operated active samplers, to characterize sampling efficiency and derive sampling rates (RS) for compounds belonging to 7 SVOC classes (including particle associated compounds). PUF-PAS efficiently and consistently sampled polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polycyclic aromatic hydrocarbons (PAHs), and eight novel brominated flame retardant (nBFR) compounds. Low accuracy and lack of sensitivity was observed for most polychlorinated dibenzo-p-dioxins/furans PCDD/Fs and polybrominated diphenyl ethers (PBDEs) (under the conditions of this study), with the exception of some congeners which may be used as qualitative markers for their respective classes. Application of compound specific RS was found crucial for all compounds except PCBs. Sampling efficiency of the particle associated compounds was often low.