Passive-sampler derived air concentrations of persistent organic pollutants on a north-south transect in Chile

Air monitoring of organochlorine pesticides (OCPs) in Bursa Türkiye: Levels, temporal trends and risk assessment

Monitoring concentration levels of persistent organic pollutants (POPs) is required to evaluate the effectiveness of international regulations to minimize the emissions of persistent organic pollutants (POPs) into the environment. In this manner, we evaluated the spatial and temporal variations of 22 organochlorine pesticides (OCPs) using polyurethane foam passive air samplers at ten stations in Bursa in 2017 and 2018. The highest concentration value for Σ22OCPs was detected in Ağaköy (775 pg/m3) and Demirtaş (678 pg/m3) sampling sites, while the lowest value was observed in Uludağ University Campus (UUC, 284 pg/m3) site. HCB, γ-HCH, Endo I, and Mirex were the most frequently detected OCPs, which shows their persistence. Diagnostic ratios of β-/(α + γ)-HCH have pointed to historical and possible illegal OCP usage in the study area. The seasonality of air concentrations (with spring and summer concentrations higher than winter and autumn concentrations) was well exhibited by α-HCH, β-HCH, ɣ-HCH, HCB, Endo I, and Mirex but not aldrin, dieldrin, and α-chlordane (CC). Levels of OCPs detected in ambient air in the current study were relatively similar to or lower than those reported in previous studies conducted in Türkiye. Back trajectory analysis was applied to identify the possible sources of OCPs detected in the sampling regions. The Clausius-Clapeyron approach was used to investigate the temperature dependence of OCP gas-phase atmospheric concentrations. The data showed that long-range atmospheric transport affects ambient air OCP concentrations in the study area.

An overview of air pollution research in Chile: Bibliometric analysis and scoping review, challenger and future directions

This study provides a comprehensive overview and bibliometric analysis of air pollution research in Chile from 1980 to 2022. The analysis reveals a significant increase in scientific production, a 9.2 annual growth rate, and an H-index of 60. The research spans 33 countries and is influenced by environmental sciences, meteorology, and atmospheric sciences journals. The top ten authors account for 33.49 % of all publications, with local institutions contributing more than 35 %. The University of Chile and the Pontifical Catholic University of Chile are significant contributors. The most cited articles focus on health impacts and various pollutant sources, emphasizing air pollution as a critical public health concern. The study also emphasizes environmental science, meteorology, and atmospheric science, focusing on topics such as air pollution and health, pollutants, models, sources and chemistry, and social sciences. The findings are affirmed through rigorous discussion and review, providing a roadmap for future research, guiding decision-making processes, and expanding the knowledge frontier in the field.

Calibration and Application of PUF Disk Passive Air Samplers To Assess Chlorinated Paraffins in Ambient Air in Australia, China, and Vietnam

Ambient air samples were collected in Brisbane (Australia), Dalian (China), and Hanoi (Vietnam) during Mar 2013-Feb 2018 using polyurethane foam based passive air samplers. A sampling rate calibration experiment was conducted for chlorinated paraffins (CPs, i.e., short-chain, medium-chain, and long-chain CPs), where the sampling rates were 4.5 ± 0.7, 4.8 ± 0.3, and 4.8 ± 2.1 m3 day-1 for SCCPs, MCCPs, and LCCPs, respectively. The atmospheric concentration of CPs was then calculated and the medians of ∑CPs were 0.079, 1.0, and 0.89 ng m-3 in Brisbane, Dalian, and Hanoi, respectively. The concentration of CPs in Brisbane's air remained at low levels, with no significant differences observed between the city background site and the city center site, indicating limited usage and production of CPs in this city. The highest concentration of MCCPs was detected in Dalian, while the highest concentration of SCCPs was detected in Hanoi. A decrease of SCCP concentration and an increase of MCCPs' were found in Brisbane's air from 2016 to 2018, while increasing trends for both SCCPs and MCCPs were observed in Dalian. These results indicated impacts from different sources of CPs in the investigated cities.

Dichlorodiphenyltrichloroethane (DDT) and Dichlorodiphenyldichloroethylene (DDE) levels in air and surface sea waters along the Antarctic Peninsula

Persistent organic pollutants (POPs) are widespread worldwide, even reaching polar regions. Among POPs, dichlorodiphenyltrichloroethane (DDT) and their metabolites have been reported scarcely in the Antarctic environment. Here we report the levels of p,p'-DDT, o,p'-DDT, p,p'-DDE, and o,p'-DDE in air and water samples collected during austral summer 2009. The levels found ranged from 0.25 to 4.26 pg m-3 in the atmospheric samples while in the water samples ranged from 0.07 to 0.25 pg L-1. These concentrations were within the range of the reported concentrations in the last 20 years in Antarctica. However, the source ratio showed that most of p,p'-DDT comes from fresh applications and Dicofol formulations. The back-trajectories estimated for the air masses revealed that most of the p,p'-DDT came from the continental Antarctic peninsula and surrounding waters. The diffusive exchange direction showed that Antarctic surface waters are the final sink of the studied compounds during the survey period.

A new insight into the emission source of DDT in indoor environment from rural area of South China and comprehensive human health exposure assessment

Human exposure to dichlorodiphenyltrichloroethanes (DDTs) and the subsequent risk to human health remain an important concern due to the "new" input of DDTs in the environment, especially since exposure to DDTs in indoor microenvironments is often ignored. In this study, we identified a new source of DDT emission in indoor environments and evaluated the health risk from the exposure to DDTs by investigating DDTs in indoor and outdoor dust, air, and coatings of household items in rural areas of Qingyuan, South China. The concentrations of DDTs in house dust and air were < MQL (method quantification limit)-3450 ng/g (median 42.4 ng/g) and 22.7-965 pg/m³ (median 49.5 pg/m³), respectively, which were significantly higher than the outdoor DDT values. Dichlorodiphenyldichloroethylene (DDE) was the main isomer in air samples, while DDT was the dominant isomer in indoor dust. Significant correlations between different DDT isomers were observed in indoor samples but not in outdoor samples. Furniture coating was identified as a source of DDTs in the indoor dust. The total daily exposure dose of DDTs (1.75 × 10^-2 ng/kg bw/day for adults and 1.28 × 10^-1 ng/kg bw/day for toddlers) through inhalation, dust ingestion, and dermal contact was found unlikely to pose a health risk. Our findings provide new insights into the emission sources and health risks caused by DDT indoors, highlighting the need to further investigate the toxicity mechanisms of parent DDT compound.

Novel eco-friendly methodology to determine polycyclic aromatic hydrocarbons in polyurethane foam for air monitoring: Application to spatial and temporal distribution survey

This study aimed at developing a new method for the extraction of polycyclic aromatic hydrocarbons (PAHs) in polyurethane foam (PUF). In the field of PAH monitoring, passive samplers using PUF disks are widely used. However, current extraction methods are time and solvent consuming. This new method employs 3 times a sixteenth of the PUF disk, with method detection limits (MDL) values below 5 and 13 ng/sampler for 3- and 4-rings PAHs, respectively. The use of only parts of the disk allows extraction by ultrasounds using exclusively 120 mL of ethanol, making it environmentally friendly. Ethanolic extracts are then purified and concentrated using microextraction by packed sorbent (MEPS) before GC-MS analyses. This method was applied for an environmental survey in a French urban area with an oceanic climate. Variations in PAH concentrations were observed depending on the site studied (urban, traffic, periurban and rural), as well as temporal variations.

Assessment of organochlorine pesticides in the atmosphere of South Korea: spatial distribution, seasonal variation, and sources

Organochlorine pesticides (OCPs) are widely used in certain countries. We determined atmospheric concentrations, distribution patterns, and seasonal variations of OCPs at four sites in South Korea for 1 year. Samples of 22 OCPs were collected using a high-volume air sampler, and measured via the isotope dilution method with HRGC/HRMS. In South Korea, pentachlorobenzene (PeCB), hexachlorocyclohexane (HCB), and endosulfan (EnSF) were dominant, accounting for > 87% of total OCPs. Spatial distributions showed significant differences and the highest levels were observed in Seosan (295.2 pg·m^-3), indicating the compounding potential of diverse sources as Seosan has concentrated large-scale industrial complexes and agricultural activity (Seoul: 243.6 pg·m^-3 > Jeju: 193.5 pg·m^-3 > Baengnyeong: 178.2 pg·m^-3). The isomeric ratios of OCPs in the South Korean atmosphere indicated that the dominant sources of HCB and dichlorodiphenyltrichloroethane were primarily used in the past; meanwhile, chlordane (CHL) and EnSFs were derived from recent material inputs. Seasonally, OCP concentrations largely peaked in summer with minimum values in winter. This apparent temperature dependence suggests the re-volatilization of accumulated chemicals into the atmosphere. Additionally, an air mass back trajectory indicated the influence of pollutants released from a reservoir through long-range atmospheric transport in the summer. In particular, restricted OCPs are primarily released into the atmosphere by inadvertent sources, such as industrial activities and volatilization from contaminated areas. Thus, severe OCP pollution in Korea is due to the mobile nature of the particles. These data can be useful for the continuous monitoring of long-range transported air pollutants that are transferred between countries.

Occurrence and air-water diffusive exchange legacy persistent organic pollutants in an oligotrophic north Patagonian lake

In this study, the occurrence and diffusive air-water exchange of POPs in Panguipulli Lake (39°42'S-72°13'W), an oligotrophic lake located in northern Patagonia (Chile), were determined. Air and water samples were collected between March and August 2017 (autumn-winter) and analyzed for concentrations of OCPs (α-HCH, β-HCH, γ-HCH and HCB) and PCBs (PCB-28,-52,-101,-118,-153,-158,-180) using gas chromatography coupled with an electron capture detector. The direction of air-water exchange direction was evaluated using a fugacity approach (ƒ_w ƒ_a^-1), and net diffusive exchange fluxes (F_AW, ng m^-2 d^-1) were also estimated. Total ∑₄OCP levels in air ranged from 0.31 to 37 pg m^-3, with a maximum for β-HCH, while Σ₇PCB levels ranged from 3.05 to 43 pg m^-3. The most abundant congener was PCB-153, accounting for 60% of the total PCBs in air. Surface water ∑₄OCPs measured in this study ranged from 1.01 to 3.9 pg L^-1, with γ-HCH predominating, while surface water Σ₇PCB levels ranged from 0.32 to 24 pg L^-1, with PCB-101, PCB-118, and PCB-153 presenting the highest levels. Diffusive air-water exchanges of HCB, α-HCH, γ-HCH and PCBs in the form of volatilization from the lake to air predominated; in contrast, for β-HCH net deposition dominated during the sampling period. Estimates suggested faster microbial degradation in the dissolved phase compared to atmospheric degradation for all analyzed POPs. Overall, these results could indicate that the oligotrophic lakes of northern Patagonia act as a secondary source of atmospheric POPs, mainly PCBs and some OCPs. This study is a first attempt to understand the occurrence of POPs in air and water, as well as their dynamics in oligotrophic lakes in the southern hemisphere.

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.

Concentrations of polychlorinated biphenyl in indoor environment of public bars and its health implications

This study determined the indoor air levels of polychlorinated biphenyls (PCBs) in some selected public bars in Southern part of Nigeria. The result obtained was used to carry out health risk assessment of exposure to PCBs in these indoor environment.s. Air samples were obtained from the selected popular bars using polyurethane (PUF) passive samplers. PCB quantification was done using GC-MS operated in selected ionization mode (SIM). Health risk assessment from exposure of these pollutants was determining using toxicity equivalence quotient (TEQ), inhalation risk assessment (IRA), incremental life cancer risk (ILCR), and hazard quotient (HQ). The results showed the average concentration range of 0.15-0.17 µg/m³. The mean TEQ at various locations was 0.00050 ng WHO-TEQ/m³, while the calculated daily inhalation exposure values were 0.0004 ng TEQ kg^-1 day^-1 for adults and 0.0002 ng TEQ kg^-1 day^-1 for children. The values of IRA, ILCR for the children, and HQs for both adults and children were higher than the WHO permissible limits. The study revealed that both non-carcinogenic and carcinogenic risks associated with longtime exposure to PCBs in the indoor environment public bars.

Introducing a nested multimedia fate and transport model for organic contaminants (NEM)

Some organic contaminants, including the persistent organic pollutants (POPs), have achieved global distribution through long range atmospheric transport (LRAT). Regulatory efforts, monitoring programs and modelling studies address the LRAT of POPs on national, continental (e.g. Europe) and/or global scales. Whereas national and continental-scale models require estimates of the input of globally dispersed chemicals from outside of the model domain, existing global-scale models either have relatively coarse spatial resolution or are so computationally demanding that it limits their usefulness. Here we introduce the Nested Exposure Model (NEM), which is a multimedia fate and transport model that is global in scale yet can achieve high spatial resolution of a user-defined target region without huge computational demands. Evaluating NEM by comparing model predictions for PCB-153 in air with measurements at nine long-term monitoring sites of the European Monitoring and Evaluation Programme (EMEP) reveals that nested simulations at a resolution of 1°× 1° yield results within a factor of 1.5 of observations at sites in northern Europe. At this resolution, the model attributes more than 90% of the atmospheric burden within any of the grid cells containing an EMEP site to advective atmospheric transport from elsewhere. Deteriorating model performance with decreasing resolution (15°× 15°, 5°× 5° and 1°× 1°), manifested by overestimation of concentrations across most of northern Europe by more than a factor of 3, illustrates the effect of numerical diffusion. Finally, we apply the model to demonstrate how the choice of spatial resolution affect predictions of atmospheric deposition to the Baltic Sea. While we envisage that NEM may be used for a wide range of applications in the future, further evaluation will be required to delineate the boundaries of applicability towards chemicals with divergent fate properties as well as in environmental media other than air.

Tracking POPs in Global Air from the First 10 Years of the GAPS Network (2005 to 2014)

The Global Atmospheric Passive Sampling (GAPS) network, initiated in 2005 across 55 global sites, supports the global monitoring plan (GMP) of the Stockholm Convention on Persistent Organic Pollutants (POPs) by providing information on POP concentrations in air on a global scale. These data inform assessments of the long-range transport potential of POPs and the effectiveness evaluation of chemical regulation efforts, by observing changes in concentrations over time. Currently, measurements spanning 5-10 sampling years are available for 40 sites from the GAPS Network. This study was the first time that POP concentrations in air were reported on a global scale for an extended time period and the first to evaluate worldwide trends with an internally consistent sample set. For consistency between sampling years, site- and sample specific sampling rates were calculated with a new, public online model, which accounts for the effects of wind speed variability. Concentrations for legacy POPs in air between 2005 and 2014 show different trends for different organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). The POPs discussed in this study were chosen due to being the most frequently detected, with detection at the majority of sites. PCB, endosulfan, and hexachlorocyclohexane (HCH) concentrations in air are decreasing at most sites. The global trends reflect global sources and recycling of HCH, ongoing emissions from old stockpiles for PCBs, and recent use restrictions for endosulfan. These chlorinated OCPs continue to present exposure threat to humans and ecosystems worldwide. Concentrations of other OCPs, such as chlordanes, heptachlor and dieldrin, are steady and/or declining slowly at the majority of sites, reflecting a transition from primary to secondary sources (i.e., re-emission from reservoirs where these POPs have accumulated historically) which now control ambient air burdens.

Temporal Distribution and Gas/Particle Partitioning of Polycyclic Aromatic Hydrocarbons (PAHs) in the Atmosphere of Strasbourg, France

Gas and particulate phase ambient air concentrations of polycyclic aromatic hydrocarbons (Ʃ16PAHs) were determined in Strasbourg, a large city located in the Alsace region of northeastern France, from May 2018 to March 2020, to study the evolution of their temporal variations and their potential origins. The analysis of PAHs was performed using a global analytical method permitting the quantification of pesticides, PAHs, and polychlorobiphenyls (PCBs). Filters and Carbon doped silicon carbide NMC@SiC foams were extracted by accelerated solvent extraction (ASE) followed by a solid-phase extraction (SPE). Afterwards, extracts were analyzed using gas chromatography coupled to tandem mass spectrometry (GC-MS/MS). Prior to analysis, a pre-concentration step based on solid-phase microextraction (SPME) was used with a polydimethylsiloxane (PDMS) 100 µm fiber. The average total (gas plus particulate) concentration of Ʃ16PAHs varied from 0.51 to 117.31 ng m−3 with a mean of 16.87 ng m−3, with higher concentrations in the cold season of more than 2.5-fold and 6-fold that in the warm season for the gas and particulate phases, respectively. Moreover, low molecular weight (LMW) (2-ring and 3-ring) and medium molecular weight (MMW) (4-ring) PAHs contribute dominantly to the gas phase, while the particulate phase is associated with MMW (4-ring) and high molecular weight (HMW) (5-ring and 6-ring) PAHs. Gas/particle partitioning coefficient (log Kp) was calculated, and values varied between −4.13 and −1.49. It can be seen that the log Kp increased with the molecular weight of the PAHs and that the log Kp is different between cold and warm seasons for HMW PAHs but not for LMW PAHs. Diagnostic ratios of PAHs, which were employed to estimate the primary source of PAHs in Strasbourg, indicate that fuel combustion and biomass/coal burning are the possible origins of PAHs in Strasbourg’s atmosphere.

Spatial and temporal distribution of Persistent Organic Pollutants and current use pesticides in the atmosphere of Argentinean Patagonia

XAD-based passive air samplers (PAS) were used to evaluate organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and some current use pesticides (chlorotalonil, trifluralin and dichlofluanid) in the atmosphere of Argentinian Patagonia. The PAS were deployed for 12 months during three consecutive years along a longitudinal (Rio Negro watershed) and a latitudinal (Patagonian coast) transect. Endosulfan, trifluralin and DDT-related substances were the most prevalent pesticides in the Rio Negro watershed, an intensive agricultural basin, consistent with ongoing use of endosulfan at the time of sampling. Concentrations of industrial contaminants were low (mean 25 pg/m³ and 1.9 pg/m³ for Σ₃₈ PCBs, and Σ₅PBDEs, respectively) and similar among sites. However, along the Patagonian coast, air concentrations of total contaminants were highly variable (14-400 pg/m³) with highest values recorded at Bahia Blanca, an important industrial area that is also downwind of the most intensively agriculturally used area of Argentina. Contaminant levels decreased toward the south, with the exception of the southernmost sampling site (Rio Gallegos) where a slight increase of total pollutant levels was observed, mainly due to the lower chlorinated PCB congeners. Interannual variability was small, although the last year tended to have slightly higher levels for different contaminant groups at most sampling sites. This large-scale spatial atmospheric monitoring of POPs and some CUPs in the South of Argentina highlights the important and continuing role of rural and urban areas as emission sources of these chemicals.

Preliminary Studies of Organochlorine Pesticides (OCPs) in Sediment, Water and Fish Samples from Ethiope River, Abraka Axis, Southern Nigeria

Selected persistent organochlorine pollutants, including DDT and its metabolites, hexachlorobenzene, dieldrin, Aldrin, heptachlor, HCH as well as some of their isomers were determined in water, sediment and fish samples from the Ethiope River in Southern Nigeria. Twenty organochlorine pesticides were detected in both seasons from October 2012 – September 2013. Results revealed ∑HCH to be 0.620µg/L (water), 33 ng/g (sediment) and 29.00 ng/g (fish) for the rainy season while concentrations of 0.170 µg/L (water), 14 ng/g (sediment) and 28.00 ng/g (fish) were obtained for the dry season. 0.05–0.15 ng/g for aldrin, 0.12–5.8 ng/g for dieldrin, 0.22–0.64 ng/g for endrin, 0.24–6.37 ng/g for endosulfan and 0.21–8.81 ng/g for ΣDDT (p, p` -DDD, p, p` -DDE, p, p` -DDT). Among the OCPs, ∑HCH, endosulfan and PDDT were the most dominant compounds in the river sediments. γ- HCH was the most frequent detected compound in all the samples from this river. Among the cyclodiene compounds, aldrin was in abundance in most of the sediments, water and fish samples. γ-HCH, γ-HCH and HCB contributed this highest value for the water, sediment and fish sample respectively in the rainy season while aldrin, endrin and HCB were the highest contributors to the ΣOCPs to the mean of water, sediment and fish respectively. Hazard quotient and bioaccumulation analysis carried out on the fish sample revealed that the fishes were heavily contaminated with values >1 for both seasons which possess a possibility for ecological concern.

Preliminary Studies of Organochlorine Pesticides (OCPs) in Sediment, Water and Fish Samples from Ethiope River, Abraka Axis, Southern Nigeria

Selected persistent organochlorine pollutants, including DDT and its metabolites, hexachlorobenzene, dieldrin, Aldrin, heptachlor, HCH as well as some of their isomers were determined in water, sediment and fish samples from the Ethiope River in Southern Nigeria. Twenty organochlorine pesticides were detected in both seasons from October 2012 – September 2013. Results revealed ∑HCH to be 0.620µg/L (water), 33 ng/g (sediment) and 29.00 ng/g (fish) for the rainy season while concentrations of 0.170 µg/L (water), 14 ng/g (sediment) and 28.00 ng/g (fish) were obtained for the dry season. 0.05–0.15 ng/g for aldrin, 0.12–5.8 ng/g for dieldrin, 0.22–0.64 ng/g for endrin, 0.24–6.37 ng/g for endosulfan and 0.21–8.81 ng/g for ΣDDT (p, p` -DDD, p, p` -DDE, p, p` -DDT). Among the OCPs, ∑HCH, endosulfan and PDDT were the most dominant compounds in the river sediments. γ- HCH was the most frequent detected compound in all the samples from this river. Among the cyclodiene compounds, aldrin was in abundance in most of the sediments, water and fish samples. γ-HCH, γ-HCH and HCB contributed this highest value for the water, sediment and fish sample respectively in the rainy season while aldrin, endrin and HCB were the highest contributors to the ΣOCPs to the mean of water, sediment and fish respectively. Hazard quotient and bioaccumulation analysis carried out on the fish sample revealed that the fishes were heavily contaminated with values >1 for both seasons which possess a possibility for ecological concern.

Passive air sampling for semi-volatile organic chemicals

During passive air sampling, the amount of a chemical taken up in a sorbent from the air without the help of a pump is quantified and converted into an air concentration. In an equilibrium sampler, this conversion requires a thermodynamic parameter, the equilibrium sorption coefficient between gas-phase and sorbent. In a kinetic sampler, a time-averaged air concentration is obtained using a sampling rate, which is a kinetic parameter. Design requirements for kinetic and equilibrium sampling conflict with each other. The volatility of semi-volatile organic compounds (SVOCs) varies over five orders of magnitude, which implies that passive air samplers are inevitably kinetic samplers for less volatile SVOCs and equilibrium samplers for more volatile SVOCs. Therefore, most currently used passive sampler designs for SVOCs are a compromise that requires the consideration of both a thermodynamic and a kinetic parameter. Their quantitative interpretation depends on assumptions that are rarely fulfilled, and on input parameters, that are often only known with high uncertainty. Kinetic passive air sampling for SVOCs is also challenging because their typically very low atmospheric concentrations necessitate relatively high sampling rates that can only be achieved without the use of diffusive barriers. This in turn renders sampling rates dependent on wind conditions and therefore highly variable. Despite the overall high uncertainty arising from these challenges, passive air samplers for SVOCs have valuable roles to play in recording (i) spatial concentration variability at scales ranging from a few centimeters to tens of thousands of kilometers, (ii) long-term trends, (iii) air contamination in remote and inaccessible locations and (iv) indoor inhalation exposure. Going forward, thermal desorption of sorbents may lower the detection limits for some SVOCs to an extent that the use of diffusive barriers in the kinetic sampling of SVOCs becomes feasible, which is a prerequisite to decreasing the uncertainty of sampling rates. If the thermally stable sorbent additionally has a high sorptive capacity, it may be possible to design true kinetic samplers for most SVOCs. In the meantime, the passive air sampling community would benefit from being more transparent by rigorously quantifying and explicitly reporting uncertainty.

Biotransport of persistent organic pollutants in the southern Hemisphere by invasive Chinook salmon (Oncorhynchus tshawytscha) in the rivers of northern Chilean Patagonia, a UNESCO biosphere reserve

Biotransport is often associated with migration patterns of species, including large, anadromous salmonids. Several studies have reported biotransport of persistent organic pollutants in the Northern Hemisphere, but there is no published information on biotransport ocurring south of the equator. Chile's Patagonia is one of the last largely intact natural areas in the world. The objective of this study was to determine whether persistent organic pollutants are transported by the invasive Pacific Chinook salmon (O. tshawytscha) from the Pacific Ocean to Chilean Patagonia. Samples of juvenile and adult Chinook salmon were analyzed for polychlorinated biphenyls, pesticides and polybrominated diphenyl ethers. The results revealed that concentrations of POPs in adults migrating into Patagonian rivers were significantly higher than those found in juveniles migrating seaward. A mass balance analysis indicates that Chinook salmon are a source of persistent organic pollutants to Chilean Patagonia inland waters. Capsule: Biotransport of Persistent Organic Pollutants (POPs) by Chinook salmon (O. tshawytscha) from the Pacific Ocean to Chilean Patagonia has been confirmed by mass balance of POPs.

Indoor persistent organic pollutants in agricultural areas from Argentina

Persistent Organic Pollutants (POPs) are anthropogenic chemicals extensively used in the past for industrial and agricultural purposes, characterized by their lipophilicity, ubiquity, volatility and environmental persistence. By other hand, chlorpyrifos is the most widely used current pesticide (CUPs) being the main insecticide used for crops in Argentina. The aim of this work was to assess levels of POPs and CUPs in different fractions of airborne particles collected indoor in agricultural areas from Argentina. Particles higher than 2.5 µm were trapped in polyurethane foams (PUF) while particles smaller than 1 µm and volatile compounds were adsorbed on activated charcoal. Compounds were analyzed by gas chromatograph with electron capture detector (GC-ECD). Endosulfans, chlordanes, PCBs, and HCHs were detected in all PUF samples, while endosulfans, chlorpyrifos, PCBs, and HCHs were the most abundant in smaller particles. Majority of pesticides showed higher concentrations during the summer season (1397.7 vs 832.5 pg/m³ ). Even adding up all measured organic compounds, no sample reaches the threshold limit value for indoor pesticides levels (0.1 pg/m³ ), neither in the large or small particle fraction. However, the fact that chronic exposure to POPs has been linked to several diseases raises concern for human health.

Polychlorinated biphenyls in the soil-crop-atmosphere system in e-waste dismantling areas in Taizhou: Concentrations, congener profiles, uptake, and translocation

Samples of soil, air, and locally grown crops from around an old e-waste dismantling area (Fengjiang) and a new e-waste dismantling area (Binhai) in Taizhou were analyzed to investigate the behavior of polychlorinated biphenyls (PCBs) released during e-waste dismantling in the soil-crop-atmosphere system. The results indicated that PCB pollution is still widespread in the study area. The PCB concentrations were clearly higher in soil from FJ than in soil from BH, and the concentrations in the functional zones decreased strongly in the order industry park > residential area > farmland. Historical and current emissions during e-waste dismantling processes are probably the main sources of PCBs to soil because PCB production and use are banned. The long half-lives of PCBs have caused the target congener concentrations in soil not to decrease markedly over 10 years. The "halo effect" may have caused PCBs in soil in the heavily polluted FJ area to diffuse into the surrounding area. Soil-air exchange of PCBs in heavily contaminated FJ area may supply PCBs to air because the temperatures in Taizhou are often high. PCBs can accumulate in crops through various pathways. Less-chlorinated PCBs (mainly including Tri-PCBs) can enter crops by root uptake and translocated to the aerial tissues, and more-chlorinated PCBs (including Penta-PCBs and Hexa-PCBs) at high concentrations in soil can enter underground crop tissues through passive transport. More-chlorinated PCBs in underground tissues cannot be transferred to aboveground tissues of tall crops but may be transferred to aboveground tissues of short crops through the root-to-stem pathway and through soil dust being transferred to aboveground external surfaces.

PAH levels in a furniture-manufacturing city atmosphere

In this study, in order to determine atmospheric PAH concentrations in Inegol/Turkey, ambient air samples were collected from two different sites representing industrial and uncontrolled furniture manufacturers regions. Sampling campaign took place between December 2017 and November 2018. Air samples were collected using high volume air samplers (HVAS) and PAH concentrations were determined in both gas and particulate phases. The mean of the atmospheric PAH concentrations obtained in the gas phase in the furniture workshops (FW) and industrial district (ID) regions were 697.82 ± 637 ng/m³ and 772.92 ± 864.23 ng/m³, respectively. The concentrations in the particulate phase in the regions were 413.52 ± 430.23 ng/m³ and 342.40 ± 527.48 ng/m³, respectively. The average total (gas + particlulate phases) concentration of ∑₁₆PAH determined in the site of FW was 1111.34 ± 1045.24 ng/m³ while that was 772.92 ± 864.23 ng/m³ in ID. These values are over the ambient levels reported for urban sites wherein big industries exist around the world. Additionally, the average of particle phase percentage was 30% because of nearby combustion sources. The determination of possible sources of PAHs in the regions was performed using principal component analysis (PCA). PCA results showed that the main sources of pollutants of the regions are intertwined (combustion, traffic, industries). However, the most effective source is thought to be uncontrolled combustion of furniture wastes as fuel for residential heating. Health risks for the citizens were calculated for both regions and were found not to be at high-class risk.

Toxic compounds in a cutlery microenterprise: A case study

BACKGROUND

The aim of this study was to characterize solid particulate aerosol derived from a cutlery microenterprise and to investigate substances associated with activities performed within the work environment.

OBJECTIVE

Suspended particulate matter (SPM) was collected at different locations in the cutlery workshop and near machines used by workers, using passive sampling devices fitted with polytetrafluoroethylene filters, onto which total particulate material was deposited. The substances present in the SPM were analyzed using gas chromatography-mass spectrometry (GC-MS).

RESULTS

Identification of the substances was performed using the National Institute of Standards (NIST) library and automated mass spectral deconvolution and identification system. (AMDIS) software, considering at least 70% probability. The concentration of total dust, obtained using a gravimetric method, was approximately 1 mg.m-3.

CONCLUSION

The toxic substances found in the SPM included halogenated hydrocarbons (containing chlorine, fluorine, and iodine) and aromatic hydrocarbons. The toxic substances included naphthalene, which is classified as carcinogenic.

Passive air sampling of halogenated polycyclic aromatic hydrocarbons in the largest industrial city in Korea: Spatial distributions and source identification

Some halogenated polycyclic aromatic hydrocarbons (Halo-PAHs) are known to be more toxic than their corresponding parent PAHs, but studies on Halo-PAHs have been somewhat limited. In this study, passive air samplers were used to monitor Halo-PAH and PAH contamination at 20 sampling sites in Ulsan, one of the largest industrial cities in South Korea. The mean concentrations of Σ₂₄ ClPAHs, Σ₁₁ BrPAHs, and Σ₁₃ PAHs were 207 pg/m³, 84 pg/m³, and 26 ng/m³, respectively. Industrial areas displayed higher concentrations of both Halo-PAHs and PAHs than urban and rural areas. Strong correlations between energetically unfavorable Halo-PAHs and their corresponding parent PAHs suggest that the main formation mechanism of Halo-PAHs is not direct halogenation of PAHs. Low molecular weight Halo-PAHs with one halogen atom and their parent PAHs were dominant. The profiles of ClPAHs and BrPAHs in petrochemical, automobile, shipbuilding, and non-ferrous industrial complexes were distinguished. The toxicity equivalency quantities (TEQs) of ClPAHs, BrPAHs, and PAHs at the industrial sites also showed the highest values of 4.2, 0.5, and 18.3 pg-TEQ/m³, respectively, reflecting the high toxicity of Halo-PAHs. To the best of our knowledge, this is the first study reporting atmospheric levels of both ClPAHs and BrPAHs using passive air samplers.

Occurrence of persistent organic pollutants in air at different sites in the province of Córdoba, Argentina

The occurrence of persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs) in the atmosphere of six sites with different emission sources in the province of Córdoba, Argentina, was analyzed. The sites included urban, industrial, agricultural, and mountain areas. Samples were collected using passive air samplers (PAS) consisting of polyurethane foam disks (PUF). Samples were analyzed for 12 PAHs, 31 polychlorinated biphenyls (PCBs), 12 organochlorine pesticides (OCPs), and 11 polybrominated diphenyl ethers (PBDEs). The concentrations of PAHs in the atmosphere were elevated at urban sites and were even higher at the industrial site. With respect to OCPs, it was observed that the concentrations of endosulfan were greater at the agricultural site (AGR) (416 ± 4 pg m^-3). For hexachlorocyclohexanes (HCHs), only the alpha isomer was detected and there were minimal differences between the different sampling sites (5.9-13.3 pg m^-3). In the case of dieldrin, the highest concentrations (33.6 pg m^-3) were found at the mountain site, which may have been due to its use for insect control. Although heptachlor epoxide was not detected, the concentration of heptachlor was significantly higher at the agricultural and downtown sites (∼ 3.6 pg m^-3). Regarding DDTs, the isomers p,p'-DDT and p,p'-DDE showed the highest concentrations at the mountain site (ΣDDT 120 ± 12 pg m^-3) and downtown site (ΣDDT 157 ± 62 pg m^-3). The relationship between the isomers suggested that at the downtown site, the contribution of this pesticide to the environment was recent, probably for the control of diseases vectors. The congener pattern of PBDEs was dominated by BDE-47, and BDE-99 at all sites, with the downtown site having the highest concentrations of compound esters (ΣPBDEs 118 ± 38 pg m^-3). Finally, high concentrations of PCBs were found at the industrial site (ΣPCBs 1677 ± 134 pg m^-3), and the predominating homologs were 5-Cl and 6-Cl, in contrast to the other sites where PCBs were dominated by 3-Cl and 4-Cl. This is the first study of POPs carried out in the province of Córdoba.

Legacy and current-use pesticides (CUPs) in the atmosphere of a rural area in central Chile, using passive air samplers

Polyurethane foam (PUF) disks in passive air samplers (PAS) and passive dry deposition (Pas-DD) collectors were used to assess the presence of persistent organic pollutants (POPs) and current-use pesticides (CUPs) in a rural area of central Chile (Peumo, VI Region). The samplers were exposed from September 2015 (spring) to March 2016 (summer), with the PUFs collected at intervals of 30, 60, and 90 days. Both samplers (PUF-PAS and Pas-DD) captured more than one pesticide per sampling period. Chlorpyrifos-ethyl and pyrimethanil presented the highest air concentration with PUF-PAS (3470.2 ng m^-3 for chlorpyrifos-ethyl and 52.8 ng m^-3 for pyrimethanil). The deposited amount of chlorpyrifos-ethyl, pyrimethanil, penconazole, diazinon and malathion in some Pas-DD, was superior to amount of pesticides captured by PUF-PAS. Differences between the amount deposited and captured by each sampler should be studied in greater detail, because wind speed, atmospheric particulate matter size and sampler design are some fundamental variables in this process. These results provide preliminary information on the presence of current-use pesticides in the atmosphere of Peumo, VI Region, serving as a foundation for future environmental monitoring programs.

A preliminary investigation of 942 organic micro-pollutants in the atmosphere in waste processing and urban areas, northern Vietnam: Levels, potential sources, and risk assessment

Of 942 organic micro-pollutants screened, 167 compounds were detected at least once in the atmosphere in some primitive waste processing sites and an urban area in northern Vietnam by using a polyurethane foam-based passive air sampling (PUF-PAS) method and an Automated Identification and Quantification System with a Database (AIQS-DB) for GC-MS. Total concentrations of organic pollutants were higher in samples collected from an urban area of Hanoi city (2300-2600 ng m^-3) as compared with those from an end-of-life vehicle (ELV) dismantling area in Bac Giang (900-1700 ng m^-3) and a waste recycling cooperative in Thai Nguyen (870-1300 ng m^-3). Domestic chemicals (e.g., n-alkanes, phthalate ester plasticizers, and synthetic phenolic antioxidants) dominated the organic pollutant patterns in all the samples, especially in the urban area. Pesticides (e.g., permethrins, chlorpyrifos, and propiconazole) were found in the atmosphere around the ELV sites at more elevated concentrations than the other areas. Levels of polycyclic aromatic hydrocarbons and their derivatives in the Bac Giang and Thai Nguyen facilities were significantly higher than those measured in Hanoi urban houses, probably due to the waste processing activities. Daily intake doses of organic pollutants via inhalation were estimated for waste processing workers and urban residents. This study shall provide preliminary data on the environmental occurrence, potential emission sources, and effects of multiple classes of organic pollutants in urban and waste processing areas in northern Vietnam.

Spatio-temporal variations of atmospheric and soil polybrominated diphenyl ethers (PBDEs) in highly industrialized region of Dilovasi

Polybrominated diphenyl ethers (PBDEs) were investigated in ambient air of a highly industrialized region at 23 different sampling sites for 12 months. Total concentrations of 8 PBDE congeners (Σ₈PBDE) were found to be between 5.73 and 520 pg m^-3 (94.7 ± 78.9; average ± SD) and BDE-209 was the predominant congener, followed by BDE-47 and/or BDE-99. Their contributions to Σ₈PBDE were 71 ± 13, 9 ± 4% and 8 ± 4%; respectively. Compared to previous studies around the world, high concentrations detected in Dilovasi demonstrated the severity of atmospheric PBDE pollution in the area. For all sampling sites, average PBDE concentration obtained in summer (118.5 ± 98.7 pg m^-3) was higher than one found in winter period (79.7 ± 59.1 pg m^-3) and this seasonal difference was more obvious in industrial/urban sites (p < 0.05), probably due to enhanced volatilization from ongoing PBDE sources such as waste incineration and iron-steel plants. The soil-air exchange tendencies of PBDEs did not show substantial differences between the sampling periods with small variations for each congener. All congeners either tend to deposit to soil or to be within the equilibrium range for all seasons. This reflects the impact of local ongoing sources rather than temperature on the direction of soil-air exchange of PBDEs in this region. Specific congener ratios such as BDE-47/-99 and -99/-100 confirmed the impact of local sources rather than long-range transport on PBDE congeners in the study area. According to the Positive Matrix Factorization (PMF) results, the BDE-209 content of the first factor was found to be 91.7% and this factor was attributed to the deca-BDE technical formulations. The second factor was highly rich with both BDE-183 (%61) and BDE-28 (%52) and identified as octa-BDE technical products. The last factor was highly loaded with BDE-99, BDE-47, BDE-100, BDE-154 and BDE-153 and has been determined as the penta-BDE commercial formulations.

Air monitoring of new and legacy POPs in the Group of Latin America and Caribbean (GRULAC) region

A special initiative in the Global Atmospheric Passive Sampling (GAPS) Network was implemented to provide information on new and emerging persistent organic pollutants (POPs) in the Group of Latin America and Caribbean (GRULAC) region. Regional-scale atmospheric concentrations of the new and emerging POPs hexachlorobutadiene (HCBD), pentachloroanisole (PCA) and dicofol indicators (breakdown products) are reported for the first time. HCBD was detected in similar concentrations at all location types (<20-120 pg/m³). PCA had elevated concentrations at the urban site Concepción (Chile) of 49-222 pg/m³, with concentrations ranging <1-8.5 pg/m³ at the other sites in this study. Dicofol indicators were detected at the agricultural site of Sonora (Mexico) at concentrations ranging 30-117 pg/m³. Legacy POPs, including a range of organochlorine (OC) pesticides and polychlorinated biphenyls (PCBs), were also monitored to compare regional atmospheric concentrations over a decade of monitoring under the GAPS Network. γ-hexachlorocyclohexane (HCH) and the endosulfans significantly decreased (p < 0.05) from 2005 to 2015, suggesting regional levels are decreasing. However, there were no significant changes for the other legacy POPs monitored, likely a reflection of the persistency and slow decline of environmental levels of these POPs. For the more volatile OCs, atmospheric concentrations derived from polyurethane foam (PUF) (acting as an equilibrium sampler) and sorbent impregnated PUF (SIP) (acting as a linear phase sampler), were compared. The complimentary methods show a good agreement of within a factor of 2-3, and areas for future studies to improve this agreement are further discussed.

Using Polyurethane Foam-Based Passive Air Sampling Technique to Monitor Monosaccharides at a Regional Scale

Monosaccharides are important tracers of pollution aerosol from biomass burning. Air sampling of monosaccharides is often conducted using active samplers. However, applicability of sampling monosaccharides using polyurethane foam passive air samplers (PUF-PASs) has not been investigated, since passive air samplers are often applied to monitor semivolatile organic contaminants in large scale and remote area. Our study successfully collected atmospheric monosaccharides using PUF-PASs, providing a valuable tool for monosaccharides sampling. PUF-PAS sampling rates for individual monosaccharides were calibrated using an active sampler for 92 days, and were 1.1, 1.5, and 1.1 m³/d for levoglucosan, mannosan, and galactosan, respectively. Degradation of monosaccharides in PUF-PAS was demonstrated to be negligible by spike test of ¹³C-labeled levoglucosan. Furthermore, passive sampling was carried out at 11 sites in the Pearl River Delta of Southern China from January to April and July to September of 2015. Monosaccharide concentrations derived from PUF-PASs were comparable with the reported data obtained by active sampling, demonstrating that the PUF-PAS approach is valid for monosaccharides monitoring. On the basis of our approach, we found that there is a clear correlation between the monosaccharide concentrations and the MODIS fire activities during January-April.

Air contamination by legacy and current-use pesticides in Brazilian mountains: An overview of national regulations by monitoring pollutant presence in pristine areas

In the last decades, research regarding the dynamics of pesticides has grown, even in remote regions. Due to long-range atmospheric transport, environmental persistence and toxicological potential of organochlorine pesticides (OCPs), similar characteristics of current-use pesticides (CUPs) and their massive use in Brazil, these contaminants have become a major concern for environmental and human life. Thus, this study aimed to evaluate subgroups or individual chemicals of OCPs and CUPs, which could have travelled over two Conservation Unit sites in the Rio de Janeiro state. The study was carried out for 24 months, (2013-2015), in Itatiaia National Park (INP) and in the Serra dos Órgãos National Park (SONP), at ∼2400 and ∼2200 meters above sea level, respectively. The study was based on atmospheric passive sampling (polyurethane foam disks). Target pesticides were detected by means of gas chromatography device coupled with mass spectrometry (GC-MS). Significantly higher concentrations were measured in SONP when compared to INP. However, in broad terms, the contamination profile was quite similar for both national parks: The highest concentrations of endosulfan (INP - 1275 pg m^-3 and SONP - 3202 pg m^-3) were followed by cypermethrin (INP - 148 pg m^-3 and SONP - 881 pg m^-3) and chlorpyrifos (INP - 67 pg m^-3 and SONP - 270 pg m^-3). In agreement with previous studies, the atmospheric concentrations of legacy OCPs showed background air levels. The decrease of endosulfan over the years was highlighted with a parallel increase of chlorpyrifos, suggesting a collateral effect of the national bias of permissive and massive use of agrochemicals. CUPs seemed to behave like pseudo-persistent pollutants (pseudo-POPs). This is the first report of atmospheric concentrations of pyrethroids in Brazilian mountain regions, and possibly the first to investigate them in the air in South America or in any mountain region in the world.

The occurrence of brominated flame retardants in the atmosphere of Gauteng Province, South Africa using polyurethane foam passive air samplers and assessment of human exposure

Polyurethane foam passive samplers were deployed between May 2016 and January 2017 to evaluate concentrations of polybrominated diphenyl ethers (PBDEs), selected alternative flame retardants (AFRs) and total hexabromocyclododecane (HBCDD) (sum of α-, β-, and γ-HBCDD). The PUF air samplers were deployed in semi-urban, urban, industrial and landfill sites in Gauteng Province, South Africa. The acquired results presented a clear semi urban-industrial-urban-landfill concentration gradient for all BFRs measured. Taking into account 2 sampling periods (cold and warm periods) (n = 16), the atmospheric concentrations of ∑₉PBDEs, HBCDDs and ∑AFRs were 100-2820 pg m^-3, 12-117 pg m^-3 and 41-4660 pg m^-3, respectively, for the sparsely populated residential area, densely populated residential area, industrial area and the landfill area. In all cases, BDE 47, 99, and 209 were the most dominant congeners with high detection frequencies. The highest calculated daily exposure dose in Gauteng Province atmosphere was 0.61 and 1.54 ng kg ^-1 - bw d ^-1 for adults and children respectively. The estimated total intake of PBDEs was 0.47-33.4 ng kg ^-1 - bw d ^-1, which was generally below the lowest adverse effect limit (LOAEL), suggesting that the residents of Gauteng Province may not be significantly affected as a result of their exposure to these pollutants through inhalation. However, this does not necessarily suggest that the pollutants are harmless to human health, since they have the tendency to bioaccumulate in biological systems. Incidentally, this is the first study from Africa to report on the atmospheric concentrations of PBDEs, HBCDDs and AFRs in urban, landfill and industrial areas. The findings from this study further highlight the contributory role of landfills as potential sources of BFRs into the atmosphere.

Atmospheric concentrations and trends of poly- and perfluoroalkyl substances (PFAS) and volatile methyl siloxanes (VMS) over 7 years of sampling in the Global Atmospheric Passive Sampling (GAPS) network

Poly- and per-fluoroalkyl substances (PFAS) and volatile methyl siloxanes (VMS) were monitored at 21 sites in the Global Atmospheric Passive Sampling (GAPS) Network. Atmospheric concentrations previously reported from 2009 were compared to concentrations measured at these sites in 2013 and 2015, to assess trends over 7 years of monitoring. Concentrations of the fluorotelomer alcohols (FTOHs) and fluorinated sulfonamides and sulfonamidoethanols (FOSAs and FOSEs) were stable at these sites from 2009 to 2015 with no significant difference (p > 0.05) in concentrations. Elevated concentrations of all the neutral PFAS were detected at the urban sites as compared to the polar/background sites. The perfluorosulfonic acids (PFSAs), meanwhile, saw a significant increase (p < 0.001) in concentrations from 2009 to 2015. The perfluorocarboxylic acids (PFCAs) had elevated concentrations in 2015, however, the difference was not statistically significant (p > 0.05). Concentrations of the PFSAs and the PFCAs were similar at all location types, showing the global reach of these persistent compounds. Concentrations of the cyclic VMS (cVMS) were at least an order of magnitude higher than the linear VMS (lVMS) and the PFAS. Octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6) saw a weak significant increase in concentrations from 2009 to 2013 (p < 0.05), however, hexamethylcyclotrisiloxane (D3) had a strong significant decrease in concentrations from 2009 to 2015 (p < 0.01).

Organophosphate ester (OPEs) flame retardants and plasticizers in air and soil from a highly industrialized city in Turkey

Passive air samples were collected at eight sites in Bursa, Turkey during five sampling periods between February-December 2014. Locations encompassed urban, suburban, industrial, rural and background environments. Soil samples (n=8) were collected at each site during February 2014. Six OPEs were detected in samples: tris(2-chloroethyl) phosphate (TCEP), tris(chloropropyl) phosphate (TCPP), triphenyl phosphate (TPHP), tris(2-butoxyethyl) phosphate (TBOEP), tris(2-ethylhexyl) phosphate (TEHP), and tris(2-isopropylphenyl) phosphate (T2iPPP). Frequency of detection in air samples was TCPP and TPHP (100%)>TBOEP (88%)>TCEP (85%)>TEHP (78%)>T2iPPP (20%). Total OPEs in air per site by sampling period (excluding non-detects) ranged from 529 to 19,139pg/m³. In soil, total OPEs ranged from 38 to 468ng/g dw. In air, alkylated OPEs dominated followed by halogenated and aryl OPEs. In air, annual mean concentrations were TBOEP>TCPP>TPHP>T2iPPP>TEHP>TCEP. In soils, alkylated OPEs were dominant at six sites and chlorinated OPEs at two sites. A comparison of OPE profiles between air and soil suggests that soils may be partly a source of OPEs to air. Mean concentrations in air were not directly proportional to temperature, and there were differences between alkylated compared to halogenated and aryl OPEs. In air, total and alkylated OPEs levels were fairly uniform, whereas more variability was found for the halogenated and aryl compounds. The relative contribution to total OPEs decreases for alkylated OPEs and increases for halogenated OPEs in samples going from background to suburban to urban and industrial sites. Levels of individual OPEs were all positively correlated between air and soils. In air, correlations between individual compounds were weak to moderate and were only statistically significant for TBOEP and TPHP. In soils, correlations were generally stronger and statistically significant only for TPHP and T2iPPP.

Effects of room airflow on accurate determination of PUF-PAS sampling rates in the indoor environment

Accurate and precise interpretation of concentrations from polyurethane passive samplers (PUF-PAS) is important as more studies show elevated concentrations of PCBs and other semivolatile air toxics in indoor air of schools and homes. If sufficiently reliable, these samplers may be used to identify local sources and human health risks. Here we report indoor air sampling rates (Rs) for polychlorinated biphenyl congeners (PCBs) predicted for a frequently used double-dome and a half-dome PUF-PAS design. Both our experimentally calibrated (1.10 ± 0.23 m3 d-1) and modeled (1.08 ± 0.04 m3 d-1) Rs for the double-dome samplers compare well with literature reports for similar rooms. We determined that variability of wind speeds throughout the room significantly (P < 0.001) effected uptake rates. We examined this effect using computational fluid dynamics modeling and 3-D sonic anemometer measurements and found the airflow dynamics to have a significant but small impact on the precision of calculated airborne concentrations. The PUF-PAS concentration measurements were within 27% and 10% of the active sampling concentration measurements for the double-dome and half-dome designs, respectively. While the half-dome samplers produced more consistent concentration measurements, we find both designs to perform well indoors.

Emissions of Tetrachlorobiphenyls (PCBs 47, 51, and 68) from Polymer Resin on Kitchen Cabinets as a Non-Aroclor Source to Residential Air

Both Aroclor and non-Aroclor sources of airborne polychlorinated biphenyls (PCBs) were found in residential homes. We deployed passive air samplers at 16 residences and found PCB-47, PCB-51, and PCB-68 to account for up to 50% of measured indoor ΣPCBs (2700 pg m-3). Although PCB-47 and PCB-51 are neurotoxins present in Aroclor mixtures (<2.5 and <0.3 wt %, respectively), we found them at much higher levels than expected for any Aroclor source. PCB-68 is not present in Aroclor mixtures. Another non-Aroclor congener, PCB-11, a byproduct of pigment manufacturing, was found inside and outside of every household and was frequently the predominate congener. We conducted direct measurements of surface emissions and identified finished cabinetry to be a major source of PCB-47, PCB-51, and PCB-68. We hypothesize that these congeners are inadvertent byproducts of polymer sealant manufacturing and produced from the decomposition of 2,4-dichlorobenzoyl peroxide used as an initiator in free-radical polymerization of polyester resins. The presence of these three compounds in polymer products, such as silicone, has been widely noted, but to our knowledge they have never been shown to be a significant environmental source of PCBs.

Calibration and evaluation of PUF-PAS sampling rates across the Global Atmospheric Passive Sampling (GAPS) network

Passive air samplers equipped with polyurethane foam (PUF-PAS) are frequently used to measure persistent organic pollutants (POPs) in ambient air. Here we present and evaluate a method to determine sampling rates (R_S), and the effective sampling volume (V_eff), for gas-phase chemical compounds captured by a PUF-PAS sampler deployed anywhere in the world. The method uses a mathematical model that requires only publicly available hourly meteorological data, physical-chemical properties of the target compound, and the deployment dates. The predicted R_S is calibrated from sampling rates determined from 5 depuration compounds (¹³C PCB-9, ¹³C PCB-15, ¹³C PCB-32, PCB-30, and d₆-γ-HCH) injected in 82 samples from 24 sites deployed by the Global Atmospheric Passive Sampling (GAPS) network around the world. The dimensionless fitting parameter, gamma, was found to be constant at 0.267 when implementing the Integrated Surface Database (ISD) weather observations and 0.315 using the Modern Era Retrospective-Analysis for Research and Applications (MERRA) weather dataset. The model provided acceptable agreement between modelled and depuration determined sampling rates, with ¹³C PCB-9, ¹³C PCB-32, and d₆-γ-HCH having mean percent bias near zero (±6%) for both weather datasets (ISD and MERRA). The model provides inexpensive and reliable PUF-PAS gas-phase R_S and V_eff when depuration compounds produce unusual or suspect results and for sites where the use of depuration compounds is impractical, such as sites experiencing low average wind speeds, very cold temperatures, or remote locations.

Organochlorine pesticides in surface waters from Reloncaví Fjord and the inner sea of Chiloé (~39.5°S - 43°S), Chilean Patagonia

Surface water samples from the environmental continuum spanning rivers (Petrohue, Cochamo, Puelo), fjord (Reloncaví), and the inner sea of Chiloé in Chilean Patagonia were analyzed to estimate concentration and distribution of dissolved Organochlorine pesticides (OCPs). High concentrations of HCHs, DDTs and endosulfan found in surface waters from rivers suggest that rivers are the major source of dissolved OCPs to coastal marine ecosystems. We interpret variations in the distribution and concentration as an apparent oscillation between rain and snow-scavenging processes that might determine the type of OCPs that can be preferentially deposited on mountains, glaciers, rivers, estuaries, and finally transferred to the marine realm. Predominance of α-HCH, γ-HCH, p,p'-DDE and α-endosulfan compounds suggest that the main deposition mechanism of OCPs to the Chilean Patagonia is rain scavenging. Snow and rain can be additional sources of OCPs that must be considered for future studies in fjord systems in Chilean Patagonia.

Understanding and Predicting the Fate of Semivolatile Organic Pesticides in a Glacier-Fed Lake Using a Multimedia Chemical Fate Model

Melting glaciers release previously ice-entrapped chemicals to the surrounding environment. As glacier melting accelerates under future climate warming, chemical release may also increase. This study investigated the behavior of semivolatile pesticides over the course of one year and predicted their behavior under two future climate change scenarios. Pesticides were quantified in air, lake water, glacial meltwater, and streamwater in the catchment of Lake Brewster, an alpine glacier-fed lake located in the Southern Alps of New Zealand. Two historic-use pesticides (endosulfan I and hexachlorobenzene) and three current-use pesticides (dacthal, triallate, and chlorpyrifos) were frequently found in both air and water samples from the catchment. Regression analysis indicated that the pesticide concentrations in glacial meltwater and lake water were strongly correlated. A multimedia environmental fate model was developed for these five chemicals in Brewster Lake. Modeling results indicated that seasonal lake ice cover melt, and varying contributions of input from glacial melt and streamwater, created pulses in pesticide concentrations in lake water. Under future climate scenarios, the concentration pulse was altered and glacial melt made a greater contribution (as mass flux) to pesticide input in the lake water.

Atmospheric concentrations, distributions and air-soil exchange tendencies of PAHs and PCBs in a heavily industrialized area in Kocaeli, Turkey

Dilovasi is one of the heavily industrialized areas in Turkey with serious environmental problems. In this study, the atmospheric concentration of PAHs and PCBs were measured for a whole year at 23 sites. The average ambient air Σ₁₅PAH and Σ₄₁PCB concentrations were found as 285 ± 431 ng m^-3 and 4152 ± 6072 pg m^-3, respectively. PAH concentrations increased with decreasing temperature especially in urban areas, indicating the impact of residential heating. However, PCB concentrations mostly increased with temperature probably due to enhanced volatilization from their sources. The gradient obtained for PCBs, rural < suburban < urban < industrial/urban, is more clear than those obtained for PAHs. The average Σ₁₅PAH and Σ₄₁PCB soil concentrations were found as 992 ± 1323 and 18.8 ± 32.0 μg kg^-1, respectively. PCB soil concentrations did not show significant temporal variations while PAH concentrations were variable especially for urban areas. The volatilization tendencies of low and medium molecular weight PAHs from soil to air were higher in industrial-urban areas than rural sites, showing that soil was a secondary source for PAHs. Fugacity ratios of PCBs were mostly <1.0 for the whole sampling period. Although the source/sink tendency of soil for some PCBs depends on their volatility, considering the whole data, PCBs were generally deposited to soil.

Evaluation and application of a passive air sampler for polycylic aromatic hydrocarbons (PAHs)

Sampling of 15 PAHs by the use of both passive air sampler developed (D-PAS) in our research group and PAS (C-PAS) having widespread use in the literature was conducted to compare the performances of the samplers. Sampling was carried out for 1-year period (February 2013-February 2014), in different sampling periods by employing D-PAS and C-PAS. D-PAS and C-PAS were run in parallel for 10, 20, 30, 40 and 60 days. Sampling rates were calculated for both PASs by the use of concentration values obtained from a high-volume air sampler (HVAS). It was determined that calculated sampling values are different from each other by definition of design of C-PAS and D-PAS and difference in environment as velocity of wind and temperature are having different effects upon sampling rates. Collected σ₁₅PAHs amounts of 10-day periods in spring, summer, autumn and winter were obtained as 576 ± 333, 209 ± 29, 2402 ± 910 and 664 ± 246 ng for D-PAS and 1070 ± 522, 318 ± 292, 6062 ± 1501 and 6089 ± 4018 ng for C-PAS, respectively. In addition, according to seasons, when collected PAHs in two different samplers were considered, similar results were obtained for the summer time in which no combustion takes place with the aim of domestic heating, while there were differences determined for the seasons with combustion in need of domestic heating. Gas-phase σ₁₅PAHs' concentrations were reported depending on seasons in the spring, summer, autumn and winter sequences as 46 ± 32, 9 ± 3, 367 ± 207 and 127 ± 93 ng m^-3 for HVAS, respectively.

Persistent organic pollutants (POPs) in the atmosphere of coastal areas of the Ross Sea, Antarctica: Indications for long-term downward trends

Passive air samplers were used to evaluate long-term trends and spatial distribution of trace organic compounds in Antarctica. Duplicate PUF disk samplers were deployed at six automatic weather stations in the coastal area of the Ross sea (East Antarctica), between December 2010 and January 2011, during the XXVI Italian Scientific Research Expedition. Among the investigated persistent organic compounds, Hexachlorobenzene was the most abundant, with air concentrations ranging from 0.8 to 50 pg m^-3. In general, the following decreasing concentration order was found for the air samples analyzed: HCB > PeCB > PCBs > DDTs > HCHs. While HCB concentrations were in the same range as those reported in the atmosphere of other Antarctic sampling areas and did not show a decline, HCHs and DDTs levels were lower or similar to those determined one or two decades ago. In general, the very low concentrations reflected the pristine state of the East Antarctica air. Backward trajectories indicated the prevalence of air masses coming from the Antarctic continent. Local contamination and volatilization from ice were suggested as potential sources for the presence of persistent organic pollutants in the atmosphere.

Effects of sampling interval on the passive air sampling of atmospheric PCBs levels

In this study, we collected Polychlorinated biphenyls (PCBs) using passive air samplers (PASs), between February 4, 2013 and February 2, 2014, with the sampling periods ranging from 10 to 60 days. The samples were collected with PASs that contained polyurethane foam (PUF). With these samples, 87 PCB congeners were analyzed. Sampling coefficient (R) values for the four seasons were calculated using both the high volume air sampler (HVAS) and PAS samples collected with the same time interval. The average of the annual concentrations of 87 PCB congeners, calculated using the R values specific to this study, was 234 ± 175 pg/m³. PCB congeners with 3- and 4- chlorines were dominant. The samples were collected at the same time interval but at different times to represent accumulation in the PASs. The linear regression coefficients (r) of the PCB mass accumulated in PASs against time ranged from 0.89 and 0.97 indicating that accumulation was linear. Moreover, the concentrations of the PCB congeners were statistically correlated with atmospheric conditions.

Chlorinated pesticides and natural brominated anisoles in air at three northern Baltic stations

Polyurethane foam (PUF) disk passive samplers were deployed at one inland and two island locations in the Bothnian Bay region of the northern Baltic Sea. Uptake was linear over 81-147 d and a temperature range of -2.6 to 14.2 °C for organochlorine pesticides (OCPs) and current-use pesticides (CUPs) having log K_OA ≥9 at ambient temperatures. Partial saturation of the PUF disks occurred for the more volatile OCPs hexachlorocyclohexanes (HCHs) and hexachlorobenzene (HCB), and for bromoanisoles (BAs), which are products of bromophenols released by natural and anthropogenic sources. Correction for nonlinear uptake of these was made using experimentally measured PUF-air partition coefficients. Passive-derived air concentrations of pesticides were uniform over the bay and agreed within a factor of 2 or better with levels determined by active (pumped) sampling at one of the island stations. Levels of OCPs were similar to those reported at background sites in the European and Canadian Arctic and at monitoring stations in the central Baltic and southern Scandinavia, indicating long-range transport. The insecticide chlorpyrifos was 10 times lower at bay stations than in the Canadian Arctic. Insight to sources and processes was gained by examining compound profiles. Fractions F_alpha = α-HCH/(α-HCH + γ-HCH) and F_TC = trans-chlordane/(trans-chlordane + cis-chlordane) at bay stations were higher than in the Norwegian and Finnish Arctic and similar to those at the southern monitoring stations. Volatilization of chlordanes from Baltic seawater may also modify F_TC. Higher F_TriBA = 2,4,6-TriBA/(2,4,6-TriBA + 2,4-DiBA) distinguished local volatilization from the Baltic Sea versus lower F_TriBA found at the inland site and reported in air on the Norwegian coast, suggesting westerly transport from the Atlantic across Norway and Sweden.

Field Calibration of XAD-Based Passive Air Sampler on the Tibetan Plateau: Wind Influence and Configuration Improvement

The passive air sampler based on XAD-2 resin (XAD-PAS) has proven useful for collecting atmospheric persistent organic pollutants (POPs) in remote regions. Whereas laboratory studies have shown that, due to the open bottom of its housing, the passive sampling rate (PSR) of the XAD-PAS is susceptible to wind and other processes causing air turbulence, the sampler has not been calibrated in the field at sites experiencing high winds. In this study, the PSRs of the XAD-PAS were calibrated at three sites on the Tibetan Plateau, covering a wide range in temperature (T), pressure (P) and wind speed (v). At sites with low wind speeds (i.e., in a forest and an urban site), the PSRs are proportional to the ratio T^1.75/ P; at windy sites with an average wind speed above 3 m/s, the influence of v on PSRs cannot be ignored. Moreover, the open bottom of the XAD-PAS housing causes the PSRs to be influenced by wind angle and air turbulence caused by sloped terrain. Field calibration, wind speed measurements, and computational fluid dynamics (CFD) simulations indicate that a modified design incorporating an air spoiler consisting of 4 metal sheets dampens the turbulence caused by wind angle and sloped terrain and caps the PSR at ∼5 m³/day, irrespective of ambient wind. Therefore, the original XAD-PAS with an open bottom is suitable for deployment in urban areas and other less windy places, the modified design is preferable in mountain regions and other places where air circulation is complicated and strong.

Persistent Organic Pollutants (POPs) in the atmosphere of three Chilean cities using passive air samplers

In this study passive air samplers containing polyurethane foam (PUF) disks were deployed in three cities across Chile; Santiago (STG) (n=5, sampling sites), Concepciόn (CON) (n=6) and Temuco (TEM) (n=6) from 2008 to 2009. Polychlorinated biphenyls (PCBs) (7 indicator congeners), chlorinated pesticides hexachlorocyclohexanes (HCHs), dichlorodiphenyl trichloroethanes (DDTs) and flame retardants such as polybrominated diphenyl ethers (PBDEs) were determined by gas chromatography coupled mass spectrometry (GC/MS). A sampling rate (R) typical of urban sites (4m³/day) was used to estimate the atmospheric concentrations of individual compounds. PCB concentrations in the air (pg/m³) ranged from ~1-10 (TEM), ~1-40 (STG) and 4-30 (CON). Higher molecular weight PCBs (PCB-153, -180) were detected at industrial sites (in Concepción). The HCHs showed a prevalence of γ-HCH across all sites, indicative of inputs from the use of lindane but a limited use of technical HCHs in Chile. DDTs were detected with a prevalence of p,p'-DDE accounting for ~50% of the total DDTs. PBDE concentrations in air (pg/m³) ranged from 1 to 55 (STG), 0.5 to 20 (CON) and from 0.4 to 10 (TEM), and were generally similar to those reported for many other urban areas globally. The pattern of PBDEs was different among the three cities; however, PBDE-209 was dominant at most of the sites. These results represent one of the few assessments of air concentrations of POPs across different urban areas within the same country. These data will support Chilean commitments as a signatory to the Stockholm Convention on POPs and for reporting as a member country of the Group of Latin America and Caribbean Countries (GRULAC) region.

Monitoring PAHs in the petrochemical area of Tarragona County, Spain: comparing passive air samplers with lichen transplants

The levels of 16 polycyclic aromatic hydrocarbons (PAHs) were determined in 8 passive air samples (PAS) and 6 lichen transplants (Ramalina fastigiata) deployed for a period of 2 months in different zones of Tarragona County (Catalonia, Spain), an area with an important number of chemical and petrochemical industries. The accumulated amount of the sum of the 16 PAHs ranged between 1363 to 7866 ng/sample in air samples. The highest concentration was found in the neighborhood of Puigdelfí (village of Perafort), in the vicinity of a big oil refinery and well under the potential influence of the petrochemical emissions. In lichen samples, the sum of the 16 PAHs ranged between 247 and 841 ng/g (dry weight), being the greatest value also observed in Puigdelfí. Data on the levels and profiles of PAHs in both passive monitoring methods were compared. A significant positive linear correlation was found between the concentrations of low molecular weight PAHs in lichens and the amounts accumulated in passive air samples (R = 0.827, P < 0.05), being especially significant the correlation of 4-ring PAHs (R = 0.941, P < 0.05). These results strongly suggest that lichens can be used to monitor gas-phase PAHs, providing data that can be quantitatively translated into equivalents for air.

Using a passive air sampler to monitor air-soil exchange of organochlorine pesticides in the pasture of the central Tibetan Plateau

Air-soil exchange is a key process controlling the fate of persistent organic pollutants (POPs). However, the "sink effect" of soil for POPs in Tibetan pasture has not been clear. In NamCo, in the central Tibetan Plateau (TP) where the land is covered by grass, a modified passive air sampler (PAS) (thickness: 2cm) was tested. Using the PAS, the atmospheric gaseous phase organochlorine pesticides (OCPs) at 11 heights from close-to-surface (2cm) to 200cm above ground, in summer and in winter, were measured. Concentrations of OCPs in summer were higher than those in winter. Both in summer and winter, atmospheric concentrations of OCPs decreased with decreasing height from 200 to 2cm, indicating that OCPs were being deposited from air to soil. Air deposition of OCPs was possibly driven by wind speed. Furthermore, based on air OCPs at 0-3cm near the surface, the interface exchange of OCPs between air and soil was studied by the fugacity method. The results showed that pastural soil in the TP was a "sink" of OCPs even in summer. The mean deposition fluxes of α-HCH, γ-HCH and o,p'-DDT were 0.72, 0.24 and 0.54pg/h/m², respectively, and it was estimated that the level of these pollutants in the soil will double every 24, 66 and 206years, respectively. This study will contribute to the further understanding of global cycling of POPs in different land covers.