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

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

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.

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

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

Assessing persistent organic pollutants (POPs) in the Sicily Island atmosphere, Mediterranean, using PUF disk passive air samplers.

In this study, PUF disk passive air samplers were deployed at eight sites, during two sampling periods, on the Island of Sicily in the Mediterranean basin. Samples were screened for a number of persistent organic pollutants (POPs) including polychlorinated biphenyls (PCBs) (n = 28 congeners), organochlorine pesticides (OCPs) (n = 16 compounds), and polybrominated biphenyl ethers (PBDEs n = 28) using GC-MS. PCB concentrations in air ranged ~10-300 pg m-3. The PCB pattern was dominated by lower to middle molecular weight PCBs (Cl3-5) and PCB-28 and PCB-52 were the most abundant congeners. α- and γ-Hexachlorocyclohexanes (HCHs) concentrations in air were relatively high ~420 ± 320 (50-1000) and 460 ± 340 (30-1000) pg m-3, respectively, with an average α/γ ratio of 1 ± 0.5, indicating a tendency of higher use of lindane than of technical HCH. Among DDTs, only p,p'-DDT 90 ± 15 (~10-800) and p,p'-DDE 60 ± 60 (20-400) were frequently detected. DDT/DDE = 0.4-3.0 (1.0 ± 0.7 for both periods) suggesting past and fresh inputs of DDT at the sampling sites. α-Endosulfan, recently included in Annex A of the Stockholm Convention, fluctuated between 120 ± 50 (50-1000) pg m-3. In contrast, PBDE levels were very low (0.2-2 pg m-3). Back trajectories of advection suggest that POP levels are mainly related to local sources (primary or secondary) from Sicily (50-70 % contribution of air masses), Southern Italy, and Sardinia (20 %). This study provides new information for POP levels in the atmosphere of the Mediterranean region.

Assessing Polycyclic Aromatic Hydrocarbons (PAHs) using passive air sampling in the atmosphere of one of the most wood-smoke-polluted cities in Chile: The case study of Temuco.

This study addresses human health concerns in the city of Temuco that are attributed to wood smoke and related pollutants associated with wood burning activities that are prevalent in Temuco. Polycyclic Aromatic Hydrocarbons (PAHs) were measured in air across urban and rural sites over three seasons in Temuco using polyurethane foam (PUF) disk passive air samplers (PUF-PAS). Concentrations of ΣPAHs (15 congeners) in air ranged from BDL to ∼70 ng m(-3) and were highest during the winter season, which is attributed to emissions from residential heating by wood combustion. The results for all three seasons showed that the PAH plume was widespread across all sites including rural sites on the outskirts of Temuco. Some interesting variations were observed between seasons in the composition of PAHs, which were attributed to differences in seasonal point sources. A comparison of the PAH composition in the passive samples with active samples (gas+particle phase) from the same site revealed similar congener profiles. Overall, the study demonstrated that the PUF disk passive air sampler provides a simple approach for measuring PAHs in air and for tracking effectiveness of pollution control measures in urban areas in order to improve public health.

Assessing levels and seasonal variations of current-use pesticides (CUPs) in the Tuscan atmosphere, Italy, using polyurethane foam disks (PUF) passive air samplers.

Polyurethane foam disks (PUF) passive air samplers (PAS) were deployed over 4 sampling periods of 3-5-months (≥ 1 year) at ten urban and rural locations throughout the Tuscany Region. The purpose was to assess the occurrence and seasonal variations of ten current-use pesticides (CUPs). PUF disk extracts were analyzed using GC-MS. The organophosphates insecticides; chlorpyrifos (3-580 pg m(-3)) and chlorpyrifos-methyl (below detection limit - to 570 pg m(-3)) presented the highest levels in air, and showed seasonal fluctuation coinciding with the growing seasons. The relative proportion urban/(urban + rural) ranged from 0.4 to 0.7 showing no differences between urban and rural concentrations. Air back trajectories analysis showed air masses passing over agricultural fields and potentially enhancing the drift of pesticides into the urban sites. This study represents the first information regarding CUPs in the atmosphere of Tuscany region using PAS-PUF disk.

Altitudinal and seasonal variations of persistent organic pollutants in the Bolivian Andes Mountains.

Polyurethane foam disk passive air samplers were deployed over four periods of approximately 3 months along an altitudinal gradient (1820, 2600, 4650, and 5200 masl) on the east side of the Andean mountain range in Bolivia. The purpose of the study was to assess the gas-phase concentration and the altitudinal and seasonal trends of organochlorine pesticides and polychlorinated biphenyls (PCBs). Target compounds that were regularly detected included alpha- and gamma-hexachlorocyclohexane (HCH), endosulfans, and select PCB congeners. Endosulfans and HCH concentrations increased with altitude. Enrichment factors (concentration at the highest altitude divided by concentration at the lowest altitude) ranged from 10 to 20 for HCHs and 3 to 10 for endosulfans. Air parcel back trajectory analysis indicated that, in general, the high-altitude sites were exposed to a larger airshed and hence susceptible to long-range atmospheric transport from more distant regions. Seasonal differences were also observed with SigmaHCH concentrations peaking during periods 2 and 3 (March-September 2005). Airsheds (derived from the analysis of back trajectories) for periods 2 and 3 were less oriented along the Andes range (mountain air) with greater input from coastal regions. Endosulfans peaked during periods 1 and 2 (February-June 2005) and also exhibited the highest air concentrations of the target compounds, reaching approximately 1500 pg/m3 at the two highest elevation sites. PCB air concentrations at all sites were generally typical of global background values (<12 pg/m3) and showed no increase with altitude. This is the first study to measure air concentrations of persistent organic pollutants (POPs) in Bolivia and one of only a few studies to investigate altitudinal gradients of POPs.