Polyurethane Foam Disks Research Articles

Air monitoring with passive samplers for dioxin-like persistent organic pollutants in developing countries (2017–2019)

As part of the global monitoring plan on persistent organic pollutants (GMP) under the Stockholm Convention passive air samplers equipped with polyurethane foam disks (PUFs) were applied to monitor dioxin-like POPs. For sampling, toluene-pretreated PUFs were exposed for three months during two years. Chemical analysis was performed in one accredited expert laboratory using internationally accepted methods; for comparison, all results were normalized to one PUF and 3 month exposure. Total TEQs, using WHO2005-TEFs, were lowest in the Pacific Islands countries (PAC) and had similar mean values in Africa (16.8 pg TEQ/PUF), Asia (16.9 pg TEQ/PUF), and Latin American and Caribbean countries (GRULAC, 13.3 pg TEQ/PUF). Using median values, Asia (13.4 pg TEQ/PUF) and GRULAC (13.1 pg TEQ/PUF) had higher amounts than Africa (6.1 pg TEQ/PUF) and PAC (2.1 pg TEQ/PUF). The contribution of PCDD/PCDF to the total TEQ was 2-3-times higher than from the dl-PCB. Mono-ortho PCB did not play a role in any of the samples. The previous 40 samples during 2010/2011 and the present 195 samples from 2017/2018 did not show a statistical difference (p value = 0.3), only for GRULAC, a downward trend was identified. It is recommended combining 4 PUFs to ‘annual’ samples.

Ambient air monitoring around the dioxin remediation site in Da Nang, Vietnam, using passive air samplers.

The concentrations and temporal variations of polychlorodibenzo-p-dioxins and polychlorodibenzofurans (PCDDs/PCDFs) in ambient air between March 2013 and February 2017 were investigated by passive air samplers containing polyurethane foam (PUF) disks in the dioxin remediation area using in-pile thermal desorption (IPTD) technology at Da Nang airport, Vietnam. The PCDD/PCDF concentrations in ambient air at each site depended on the location of the emission sources and the wind direction, the dioxin contamination level of excavated materials, the periods of excavation and transport, and the operation of the IPTD treatment system. The PCDD/PCDF concentrations were the highest in the former Agent Orange mixing and loading area (AOMLA), which was the closest to the IPTD system, with total toxic equivalent (TEQ) values ranging from 0.437 to 15.3pg/PUF/day. The total TEQ concentrations in the Sen Lake area ranged from 0.138 to 2.41pg/PUF/day. The lowest concentration of PCDDs/PCDFs occurred in the northern perimeter area, with total TEQ values ranging from 0.164 to 0.972pg/PUF/day. The decreasing trend of the PCDD/PCDF concentrations in ambient air was confirmed over time at all three monitoring sites, among which there was a strong decrease in the former AOMLA after February 2015. Residents living near the Da Nang airport were at a low risk of being exposed to PCDDs/PCDFs through inhalation during remediation project implementation, while residents living close to the former AOMLA faced elevated risks with an average daily dose of PCDDs/PCDFs through inhalation ranging from 0.017 to 0.82pg TEQ/kg body weight/day.

Air monitoring with passive samplers for perfluoroalkane substances in developing countries (2017–2019)

To support the global monitoring plan on persistent organic pollutants (GMP) under the Stockholm Convention, 41 countries have exposed passive air samplers equipped with polyurethane foam disks (PUFs) to monitor perfluoroalkane substances (PFAS). The recommended procedure had PUFs exposed for three months during two years; analysis was performed in one expert laboratory to generate harmonized results. Chemical analysis using Soxhlet extraction with methanol or a 60:40 MTBE:methanol mixture, solid-phase extraction and UPLC/MSMS detection posed challenges as to matrix interference and sensitivity. Single PUFs as quarterly samples and combination of up to 4 PUFs as annual samples were analyzed; all concentrations were normalized to one PUF and 3 months exposure. Exceptionally high values (up to 36 000 pg SPFOS/PUF) were observed in nine samples from Zambia where a local source was identified. For the remaining 308 PUFs, PFOA had a higher median value (188 pg/PUF) than SPFOS (125 pg/PUF) whereas the mean value of SPFOS (254 pg/PUF) was slightly higher than the mean value for PFOA (230 pg/PUF). PFHxS concentrations were much lower in concentration and detection frequency and FOSA, as the only relevant PFOS precursor compound, showed a median value of zero. No clear regional differentiation was found.

Passive Air Sampling of PCDD/Fs, PCBs, PAEs, DEHA, and PAHs from Informal Electronic Waste Recycling and Allied Sectors in Indian Megacities.

Xenobiotic chemical emissions from the informal electronic waste recycling (EW) sector are emerging problem for developing countries, with scale and impacts that are yet to be evaluated. We report an intensive polyurethane foam disk passive air sampling study in four megacities in India to investigate atmospheric organic pollutants along five transects viz., EW, information technology (IT), industrial, residential, and dumpsites. Intraurban emission sources were estimated and attributed by trajectory modeling and positive matrix factorization (PMF). ∑17PCDD/Fs, ∑25PCBs, ∑7plasticizers, and ∑15PAHs concentrations ranged from 3.1 to 26 pg/m3 (14 ± 7; Avg ± SD), 0.5-52 ng/m3 (9 ± 12); 7.5-520 ng/m3, (63 ± 107) and 6-33 ng/m3 (17 ± 6), respectively. EW contributed 45% of total PCB concentrations in this study and was evidenced as a major factor by PMF. The dominance of dioxin-like PCBs (dl-PCBs), particularly PCB-126, reflects combustion as the possible primary emission source. PCDD/Fs, PCBs and plasticizers were consistently highest at EW transect, while PAHs were maximum in industrial transect followed by EW. Concentrations of marker plasticizers (DnBP and DEHP) released during EW activities were significantly higher (p < 0.05) in Bangalore than in other cities. Toxic equivalents (TEQs) due to dl-PCBs was maximum in the EW transect and PCB-126 was the major contributor. For both youth and adult, the highest estimated inhalation risks for dl-PCBs and plasticizers were seen at the EW transect in Bangalore, followed by Chennai and New Delhi.

A first look at atmospheric concentrations and temporal trends of phthalates in distinct urban sectors of the Greater Toronto Area

Measurements of the outdoor air concentrations of phthalates (PHTs) using passive sampling media (polyurethane foam (PUF) disks) were conducted at 8 different sites across the Greater Toronto Area (GTA) during 2016–2017. Highest PHT levels were obtained at sites characterized by high levels of urban and traffic activity. The PHT profile was mainly dominated by bis(2-ethylhexyl) phthalate (DEHP), whose median air concentration across the examined sites was MDEHP = 1200 pg/m3. It was discovered that PHT levels had a strong correlation with the ambient temperature. Warmer months appeared to contribute to greater emission of PHTs at most sites. Clausius Clapeyron (CC) plots were used to investigate the presence of temperature dependent processes governing PHT emissions, such as secondary volatilization from environmental surfaces. Enthalpies of surface-air exchange calculated from CC plots were compared to respective enthalpies of vaporization for each PHT. Those values were used to examine importance of localized water-air and land-air exchanges on atmospheric levels of PHTs. The data suggested that secondary volatilizations are relevant PHT contributors and appear to depend on sampling site and PHT type. Enthalpies associated with Henry's law constant were also evaluated, providing evidence of secondary volatilization from water bodies. This work is part of an on-going study which already evaluated levels of organophosphate esters (OPEs), polybrominated diphenyl ethers (PBDEs) and polycyclic aromatic compounds (PACs) at the same sites. Ultimately, the variability in ambient concentrations of PHTs in the GTA are believed to be due to a combination of both primary and secondary sources.

High dye removal capacity of Peniophora laxitexta immobilized in a combined support based on polyurethane foam and lignocellulosic substrates

ABSTRACT Dye removal from effluents is a major problem for most textile industries. At present, wastewater treatments are currently based on physico-chemical methods which are expensive, energy inefficient and of limited versatility. The aim of this work was to find a low-cost and efficient method for dye removal. To do this, we designed a combined system based on the immobilization of the ligninolytic white-rot fungus Peniophora laxitexta (BAFC 4687) on mixed supports consisting of two polyurethane foam discs and a middle layer of diverse lignocellulosic substrates: soybean hulls, wheat straw or cellulose spent casings. As a corticioid fungus, P. laxitexta was able to completely colonize the supports developing a compact and tight structure that maintained the integrity of the system after several dye removal cycles. The immobilized fungus removed between 30% and 50% of the azoic dye Xylidine and more than 50% of the anthraquinonic dye RBBR in three successive cycles, and near 90% of the triphenylmethane Malachite Green in 10 repeated cycles without any loss of efficiency. Our analysis showed that the removal of the dyes was due to the combined effect of adsorption to the supports and enzymatic decolorization by soluble laccases and enzymes associated with the mycelium. Additionally, we showed that the presence of Malachite Green induced the expression of a new laccase isoform with high decolorization capacity. Based on these results, we propose that this inoculated laminar biocarrier could be effectively used for dye removal in textile wastewater.

PUF PAS를 이용한 대기 중 PCBs 농도 산정

This study was conducted to evaluate the use of low volume air sampler (LVAS) and polyurethane foam disk passive air samplers (PUF PAS) for better measurement of atmospheric polychlorinared biphenyls (PCBs) concentrations. Air samples were collected by a low volume air sampler (LVAS) and PUF PAS, a total of two pairs were continuously collected at the same time for 4 weeks. A good correlation was shown [MonoCB∼DiCB : R²=0.8289(p=0.012), TriCB∼HexaCB : R²=0.8388(p<0.0001)] between atmospheric PCBs concentration measured by the LVAS and PUF PAS. The sampling rate of all PCBs isomers showed higher than which were measured by other researchers in different cities. However, trace POPs such as PCBs may involve relatively large analytical errors in measurement, and as a result the air sampling rate of the respective PCB isomer is also likely to involve errors. The method of using a regression straight line between the concentrations obtained by the LVAS and those from the PUF PAS was judged better than the method using the sampling rate, since the former compensated for the experimental errors in the process of evaluation of atmospheric PCBs concentrations using the PUF PAS.

Spatial distribution, patterns and source contributions of POPs in the atmosphere of Great Mendoza using the WRF/CALMET/CALPUFF modelling system

Abstract Global monitoring of Persistent Organic Pollutants (POPs) has allowed the knowledge of levels and distribution around the world as well as the understanding of its transport through the atmosphere. However, there are still some gaps in this regard, especially in some locations, as the case of Great Mendoza, a medium-sized urban area located in the center-west of Argentina. In this work, the WRF/CALMET/CALPUFF modeling system was used to estimate airborne levels of four families of POPs (PCBs, PBDEs, DDTs and HCB) in the study area. The model was validated from measured data obtained from eleven sites using passive air samplers with polyurethane foam disks (PUFs), subsequently analyzed by GC-ECNI/MS. Considering both sets of data, measured and simulated airborne concentrations, five statistical performance metrics were calculated for each family of POP [Mean bias error, (MBE), Fractional Bias (FB), Normalized Mean Square Error (NMSE), Factor of two (Fa2) and Pearson correlation coefficient (r)]. Results exhibited a good agreement between modeled and measured data, showing that WRF/CALMET/CALPUFF modeling system predicts POPs airborne concentrations with reasonable accuracy at a local scale. Model output was used to examine the relative source contribution to ground-level concentrations and to assess the spatial variability of the studied POPs in the study area. Source apportionment showed the prevalence of emissions from open burning of municipal solid waste (ranging from 9% to 90%) on the simulated atmospheric concentrations. HCB presented the lowest mean contribution from this activity (37%) but the highest variability (SD = 20%), followed by PCBs (69 ± 9%), and PBDEs (84 ± 4%). The spatial pattern obtained from simulations exhibited that both, lowest and highest levels predicted by the model, occurred in areas where no samples were taken, suggesting that the real gradient in the POPs air concentrations would be much greater than those reflected by measured data. This work highlights the usefulness of the implementation of an atmospheric dispersion model, not only in the study of air quality and exposure levels but also as a tool for the proper design of monitoring networks, taking into account the time and cost that sampling campaigns take, and the conclusions that are intended to be made from the analysis of the obtained data.

Polyurethane foam disk passive sampler derived air concentrations of persistent organic pollutants in an agricultural region with hot climate

Polyurethane foam (PUF) disks passive air samplers were deployed in an agricultural region with hot climate to determine atmospheric concentrations of 22 organochlorine pesticides (OCPs) and 15 polychlorinated biphenyls (PCBs). Sampling rates (2.39–15.9 m3.day−1) increased with rising ambient air temperatures. Total OCP and PCB concentrations were 0.884–97.0 pg.m−3 and nd-213 pg.m−3, respectively. The most prominent OCPs in the samples were hexachlorocyclohexane (HCH) isomers, chlordane compounds, dichlorodiphenyltrichloroethane (DDT) derivatives, and endosulfan isomers. The isomer ratios of DDT and Chlordane in the samples indicated older usage while endosulfan ratios showed recent input of technical endosulfan in the region. Total PCB levels were dominated by low chlorinated congeners. The contaminant levels in air samples were mainly lower or similar by comparison to other studies conducted at agricultural regions worldwide. Although the production and use of these chemicals have been banned, results of this study show that some of the chemicals could still be found in agricultural areas. Presence of these chemicals in environmental samples may be result of the degradation of formerly used chemicals, atmospheric transport or illegal use of banned chemicals.

Polyurethane Foam (PUF) Disk Samplers for Measuring Trace Metals in Ambient Air

A new method is presented for measuring atmospheric concentrations of trace metals in airborne particulate matter using polyurethane foam (PUF) disk passive air samplers (PUF-PASs) and passive dry ...

Direct measurements of polyurethane foam (PUF) ‒ air partitioning coefficients for chemicals of emerging concern capable of equilibrating in PUF disk samplers

Organophosphate esters (OPEs), novel flame retardants (NFRs) and organochlorine pesticides (OCPs) are volatile to semi-volatile chemicals and therefore susceptible to approach equilibrium during typical deployments of polyurethane foam (PUF) disk passive air samplers. A generator column approach was used to measure the PUF-air partitioning coefficient (KPUF-air) for these targeted chemicals. KPUF-air values are required for these chemicals to estimate sampled equivalent air volumes, which vary substantially with temperature. Log KPUF-air measurements were made at temperatures ranging from+6 to+35°C and resulting values ranged from 5.14 to 7.77. Enthalpies of phase change for PUF to air (ΔHPUF-air, kJ/mol) ranged from 51.3 to 98.9. Two relationships of log KPUF-air versus log Koctanol-air (KOA) were derived, grouping OPEs and NFRs separately. The relationship for NFRs was in fair agreement (within about 0.6 log units) to a long-standing relationship by Shoeib and Harner (since 2002) for polychlorinated biphenyls (PCBs). However, the estimated values using Shoeib-Harner relationship substantially underestimates KPUF-air for the OPEs than directly measured values (by about an order of magnitude). These findings highlight the importance of the direct measurements of KPUF-air for emerging classes of chemicals whose concentrations are at risk of equilibrating in PUF disk samplers.

Atmospheric Occurrence of Legacy Pesticides, Current Use Pesticides, and Flame Retardants in and around Protected Areas in Costa Rica and Uganda.

Protected areas have developed alongside intensive changes in land use and human settlements in the neighboring landscape. Here, we investigated the occurrence of 21 organochlorine pesticides (OCPs), 14 current use pesticides (CUPs), 47 halogenated flame retardants (HFRs), and 19 organophosphate esters (OPEs) in air around Las Cruces (LC) and La Selva (LS) Biological Stations, Costa Rica, and Kibale National Park (KNP), Uganda using passive air samplers (PAS) with polyurethane foam (PUF) discs (PAS-PUF). Significantly higher concentrations of CUPs were observed around LS, while LC had a higher concentration of OCPs. Land use analysis indicated that LS had a higher fraction of agriculture than LC (33% vs 14%), suggesting the higher CUPs concentration at LS was related to pesticide intensive crops, while higher OCPs concentration at LC may be attributed to the area's long agricultural history characterized by small-scale subsistence farming or long-range transport. In Uganda, CUPs and OCPs were generally lower than in Costa Rica, but high concentrations of HFRs were observed inside KNP, possibly due to human activity at research camps near the protected forest. This is the first study that documented the occurrence of anthropogenic chemicals in the air at protected areas with tropical forests.

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 ± 4pgm-3). For hexachlorocyclohexanes (HCHs), only the alpha isomer was detected and there were minimal differences between the different sampling sites (5.9-13.3pgm-3). In the case of dieldrin, the highest concentrations (33.6pgm-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 (∼3.6pgm-3). Regarding DDTs, the isomers p,p'-DDT and p,p'-DDE showed the highest concentrations at the mountain site (ΣDDT 120 ± 12pgm-3) and downtown site (ΣDDT 157 ± 62pgm-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 ± 38pgm-3). Finally, high concentrations of PCBs were found at the industrial site (ΣPCBs 1677 ± 134pgm-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.

Determination of Semivolatile Organic Nitrates in Ambient Atmosphere by Gas Chromatography/Electron Ionization–Mass Spectrometry

Semivolatile organic nitrates (SVONs) contribute a large proportion of total organic nitrates and play an important role in the tropospheric chemistry. However, the composition and concentrations of SVONs in the atmosphere remain unclear due to the lack of reliable analytical techniques for specific organic nitrates. In this study, a method based on gas chromatography and electron ionization–mass spectrometry was developed to detect ambient SVONs that were collected via polyurethane foam disk enrichment. Three SVONs were identified in the semivolatile samples from urban Jinan during spring based on the characteristic fragment ions of [NO2]+ and [CH2NO3]+ and the characteristic fragment loss of NO2 and NO3: 1-pentyl nitrate (molecular weight [MW] = 133), 4-hydroxy-isoprene nitrate (MW = 147), and (3,4)-di-hydroxy-isoprene nitrate (MW = 163). The latter two isoprene nitrates were rarely detected in the real atmosphere in previous studies. The contents of 1-pentyl nitrate, 4-hydroxy-isoprene nitrate, and (3,4)-di-hydroxy-isoprene nitrate were roughly quantified based on the standard of 1-pentyl nitrate, with a detection limit of 50 μg L−1. In addition, Fourier transform infrared spectrometry was used to determine the total SVONs content. The average concentrations of 1-pentyl nitrate, 4-hydroxy-isoprene nitrate, (3,4)-di-hydroxy-isoprene nitrate, and total SVONs in Jinan during spring were 20.2 ± 7.2, 13.2 ± 7.2, 36.5 ± 8.4, and 380.0 ± 190.8 ng m−3, respectively. The three identified SVONs contributed only 20.2 ± 5.5% to the total SVONs, which suggests that some unidentified SVONs are present in the ambient atmosphere and that studies with improved or advanced analytical techniques will be required to identify them.

Temporal and Spatial Trends of Polycyclic Aromatic Compounds in Air across the Athabasca Oil Sands Region Reflect Inputs from Open Pit Mining and Forest Fires

Results of a passive air monitoring study for polycyclic aromatic compounds (PACs) in the Athabasca oil sands region (AOSR) in Alberta, Canada, are reported. Polyurethane foam disk passive air samplers were deployed for consecutive 2-month periods from November 2010 to January 2016 at 15 sites. Samples were analyzed for polycyclic aromatic hydrocarbons (PAHs), alkylated PAHs (alkPAHs), and dibenzothiophene and its alkylated derivatives (DBTs). Concentrations in air were in the ranges of 0.3–43, 0.15–460, and 0.04–130 ng/m3 for ∑PAHs, ∑alkPAHs, and ∑DBTs, respectively. The increase in the levels of PACs in air at most sites was small but statistically insignificant over this 5-year period, which is consistent with expectations as in situ bitumen extraction techniques have become predominant over open pit mining in the area. Significant increases in PAC levels were observed at a site that is within a few kilometers of open pit mining that expanded over the study period. The 5-year regional trend for PACs in...

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.

Passive indoor air sampling for consumer product chemicals: a field evaluation study.

Innovative exposure measurement methods are needed for large environmental health studies, particularly for semivolatile organic compounds (SVOCs). Active air sampling methods are costly to implement, but passive air sampling presents a viable method. To expand and improve the use of passive air samplers (PAS) for indoor SVOC monitoring, we designed a unique, compact sampler using commercially available polyurethane foam (PUF) disks housed within durable, easy-to-setup, low-profile enclosures. We evaluated the new design using co-located active air samplers (AAS) and analyzed for SVOCs. Most of the targeted SVOCs found using active sampling (27 of 33) were also detected using passive sampling. We found good agreement (R2 = 0.88) between active and passive sampling methods for characterizing the relative abundance of each chemical, and the measured active sampler concentrations and passive sampler masses were significantly positively correlated for 14 of 21 chemicals, for which correlations could be estimated. We found that measurements of many SVOCs originating from consumer products and typically found in the gas-phase (log KOA < 10) can be reliably ranked-and thus appropriate for epidemiological studies-using this PAS design. These SVOCs include diethyl phthalate, AHTN, HHCB, tris(2-chloroethyl) phosphate, dibutyl phthalate, and tris(1-chloro-2-propyl) phosphate, as well as methyl paraben, benzophenone, and benzophenone-3, which have not previously been measured by passive sampling. This PAS can be used in epidemiological studies involving consumer product chemicals and complements other novel exposure tools.

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.

Global Atmospheric Concentrations of Brominated and Chlorinated Flame Retardants and Organophosphate Esters.

Polyurethane foam (PUF) disk passive air samples, deployed during 2014 in the Global Atmospheric Passive Sampling (GAPS) Network, were analyzed for a range of flame retardants (FRs) including polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), brominated and chlorinated novel FRs, and organophosphate esters (OPEs). Mean concentrations of PBDEs and novel FRs at the 48 sites monitored ranged from 0.097 to 93 pg/m3 for Σ14PBDEs and from below detection limits to 126 pg/m3 for Σ15novel FRs. For PBDEs, the detected concentrations were similar to those previously reported from samples collected in 2005 at GAPS sites, suggesting global background atmospheric concentrations of PBDEs have not declined since regulatory measures were implemented. OPEs were detected at every GAPS site, with Σ18OPEs ranging from 69 to 7770 pg/m3. OPE concentrations were at least an order of magnitude higher than the PBDEs. This study presents the first data on global distributions of OPEs in the atmosphere, obtained from a single passive sampling monitoring network. Challenges that can arise in passive air sampling campaigns are also highlighted and addressed with suggested recommendations for future campaigns.

Passive air sampling of polybrominated diphenyl ethers in New Delhi, Kolkata, Mumbai and Chennai: Levels, homologous profiling and source apportionment

Several studies in the recent past reported new sources for industrial persistent organic pollutants (POPs) from metropolitan cities of India. To fill the data gap for atmospheric polybrominated diphenyl ethers (PBDEs), polyurethane foam disk passive air sampling (PUF-PAS) was conducted along urban-suburban-rural transects in four quadrilateral cities viz., New Delhi, Kolkata, Mumbai and Chennai from northern, eastern, western and southern India respectively. Average concentration of Σ8PBDEs in pg/m3 for New Delhi, Kolkata, Mumbai and Chennai were 198, 135, 264 and 144 respectively. We observed a distinct urban > suburban > rural trend for atmospheric PBDEs in Mumbai. Principal component analysis (PCA) attributed three different source types. BDE-47, -99, −100, −153 and −154 loaded in the first component were relatively high in the sites where industrial and informal electronic waste (e-waste) recycling activities were prevalent. Penta congener, BDE-99 and tetra congener, BDE-47 contributed 50%–75% of total PBDEs. Ratio of BDE-47 and -99 in Indian cities reflected the usage of penta formulations like Bromkal −70DE and DE-71 in the commercial and electrical products. PC-2 was loaded with BDE-28 and -35. Percentage of BDE-28 and BDE-35 (>10%) were comparatively much higher than commercial penta products. Abundance of BDE-28 in majority sites can be primarily due to re-emission from surface soil. PC-3 was loaded with BDE-183 and elevated levels were observed mostly in the industrial corridor of Indian cities. BDE-183 was notably high in the urban industrial sites of New Delhi. We suspect this octa-BDE congener resulted from recycling process of plastic products containing octa-BDE formulation used as flame retardants.