A study of aerosol entrapment and the influence of wind speed, chamber design and foam density on polyurethane foam passive air samplers used for persistent organic pollutants.

Polyurethane foam disks are a cheap and versatile tool for sampling persistent organic pollutants (POPs) from the air in ambient, occupational and indoor settings. This study provides important background information on the ways in which the performance of these commonly used passive air samplers may be influenced by the key environmental variables of wind speed and aerosol entrapment. Studies were performed in the field, a wind tunnel and with microscopy techniques, to investigate deployment conditions and foam density influence on gas phase sampling rates (not obtained in this study) and aerosol trapping. The study showed: wind speed inside the sampler is greater on the upper side of the sampling disk than the lower side and tethered samplers have higher wind speeds across the upper and lower surfaces of the foam disk at a wind speed 4 m/s; particles are trapped on the foam surface and within the body of the foam disk; fine (<1 um) particles can form clusters of larger size inside the foam matrix. Whilst primarily designed to sample gas phase POPs, entrapment of particles ensures some sampling of particle bound POPs species, such as higher molecular weight PAHs and PCDD/Fs. Further work is required to investigate how quantitative such entrapment or sampling is under different ambient conditions, and with different aerosol sizes and types

Screening for PFOS and PFOA in European air using passive samplers

Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) have been widely detected in the environment and in wildlife, including biota in remote areas, such as the Arctic. A monitoring programme to measure these two compounds in the atmosphere simultaneously at many sites using traditional sampling techniques (active air sampler) would be difficult to achieve. This study presents the results of using polyurethane foam-based passive air samplers (PUF-PASs) to sample ionic perfluoroalkyl sulfonates (PFASs) in three different areas: northwest of England (15 sites), UK-Norway transect (11 sites) and European survey (23 sites), for 2-3 months of exposure. Only PFOA and PFOS were regularly detected in the samplers. PFOA (200-27000 pg per sample per day) and PFOS (1.5-720 pg per sample per day) levels present in samplers deployed in northwest of England were estimated in this study. In the UK-Norway transect campaign, only the UK samples were found to contain PFOA (100-1200 pg per sample per day) and PFOS (2.7-7.7 pg per sample per day). It was difficult to see clear distribution trends of PFOA (4.7-540 pg per sample per day) and PFOS (1.9-69 pg per sample per day) in the EU survey. However, PFOA appeared relatively elevated in samples taken close to the coastline of the North Sea. This study gives some encouragement to the idea that PUF-PAS can be used to sample PFASs. From our knowledge, this is the first study using untreated PUF disks to sample ionic PFASs in the atmosphere

PCB and organochlorine pesticide burden in eels in the lower Thames River (UK)

Thirty-five European eels (Anguilla anguilla), caught in 2007 in the river Thames upstream and downstream of both London and the tidal limit, were analysed for PCBs and organochlorine pesticides. Most chemicals were detectable in every fish, although they have been banned or severely restricted for many years. In general, the tidal eels were more contaminated than upstream ones, which was related to their higher lipid contents. The ICES7 indicator PCB concentrations ranged overall from 4.2 to 124μgkg(-1) fresh weight with averages of 33 and 56μgkg(-1) for the upstream and tidal eels; 3.5-104μgkg(-1), average 26 and 48μgkg(-1) of that were ICES6 PCBs. Total DDT was on average 16μgkg(-1) (1.7-38μgkg(-1)) upstream and 18μgkg(-1) (8.6-35μgkg(-1)) downstream with about half of that provided by pp'DDE. Lindane (γ-HCH) was found at up to 2.8μgkg(-1) (averages 0.58 and 1.1μgkg(-1) upstream and downstream) and hexachlorobenzene (HCB) was on average 1.9 and 2.5μgkg(-1) in the two groups with a maximum of 6.4μgkg(-1) in each. Therefore all individuals passed the European Environmental Quality Standard (EQS) of 10μgkg(-1) for HCB. PCB contamination was fairly typical for recent UK eel data, whilst DDE and lindane concentrations were lower than most previous UK eel studies, perhaps reflecting a downward trend. Although not as highly contaminated as some eels from previous UK and European studies, the presence of so many of these chemicals, with their known health effects may represent a stress for the fish or higher predators, such as birds

Validation of a passive atmospheric deposition sampler for polybrominated diphenyl ethers.

An atmospheric deposition sampler was validated with respect to polybrominated diphenyl ethers (PBDEs), a compound group that is widely used as flame retardants in many types of consumer products. The deposition sampler consists of an adsorption cartridge that is connected to a glass funnel. Extraction tests with spiked cartridges using soxhlet extraction with acetone revealed recoveries of >80% for all of the investigated PBDEs. Once adsorbed, PBDEs are stable, as proven by extractions of spiked cartridges that were stored outdoors and collected after different periods of time, up to 84 days. High recoveries indicate that degradation of adsorbed PBDEs does not play a role under realistic field conditions. Bulk deposition rates of PBDEs were determined in a field test with 3 replicates, and a possible breakthrough of target compounds was assessed in the field using a second adsorption cartridge in series. No breakthrough of target compounds could be observed within a sampling period of 61 days, and a bulk deposition rate of approximately 1 ng m–2 day–1 for the sum of all analysed PBDEs was measured. The highest deposition rates were measured for octa-brominated congeners, followed by BDEs 99, 183, 153, and 47. Overall, the sampler was successfully validated regarding the atmospheric deposition of PBDEs

Concentrations of decabromodiphenyl ether in air from Southern Ontario : implications for particle-bound transport.

Atmospheric concentrations are reported for the main component of the brominated flame retardant decaBDE (BDE-209) in air samples collected from Southern Ontario for the period January 23–June 06, 2002. Levels ranged from below detection to 105 pg m−3 with virtually all of BDE-209 being trapped by the filter and thus deduced to be sorbed to aerosol particles. Thus, it is likely that the long-range atmospheric transport (LRAT) of BDE-209 is controlled by the transport characteristics of the aerosols. This conclusion that BDE-209 does not have the same potential for LRAT as other more volatile PBDEs is subject to possible complications arising from the uncertainties about the LRAT potential of aerosols

The influence of land use on the concentration and vertical distribution of PBDEs in soils of an e-waste recycling region of South China

Accepted ManuscriptRGCOthersNational Natural Science Foundation of China; Natural Science Foundation of Guangdong Province; GIGCASPublishe

Further studies on the uptake of persistent organic pollutants (POPs) by polyurethane foam disc passive air samplers

Passive air samplers (PAS) can be used to monitor semi-volatile organic compounds in the atmosphere. Polyurethane foam (PUF) disks are a popular sampling medium because they have a high retention capacity for such compounds. This paper reports a highly time-resolved uptake study, to derive uptake rate data under field conditions, and investigate the effects of using different foam densities on the uptake rate. PUF disks were deployed alongside an active sampler, for periods of up to 12 weeks. The uptake rates were measured for a range of gas- and particle-bound persistent organic pollutants (polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs)), of different properties, to explore whether gas–particle partitioning affected uptake rate. Uptake rates for two different densities of foam (0.021 and 0.035 g cm−3) were not statistically significantly different from each other. Uptake rates of light PCBs averaged 6.5 m3 day−1, somewhat higher than in previous studies; higher wind speeds and lower temperatures in this study are the likely reason for this difference. The study showed: i) the uptake rate of the compound with lowest KOA considered in this study (PCB-28/31) declined in the later weeks, indicating an approach to equilibrium; ii) uptake rates of lighter BDEs and heavier PCBs (compounds of intermediate KOA in this study) remain similar throughout the study period, indicating that they are not approaching equilibrium during the 12-week-study; iii) uptake rates were typically: 8 m3 day−1 for PCB-52; 9.5 m3 day−1 for PCB-95; 11 m3 day−1 for BDE-28 and 2 m3 day−1 BDE-99. The latter compound has an important particle-bound component and this lowers the sampling rate compared to predicted uptake rates for compounds which are in the gas phase only. It is shown that knowledge of gas–particle partitioning is needed to correct for this effect, and to improve predicted uptake rates

Screening of Atmospheric Short- and Medium-Chain Chlorinated Paraffins in India and Pakistan using Polyurethane Foam Based Passive Air Sampler

Production and use of chlorinated paraffins (CPs) have been increasing in India. Distribution of CPs in the area and vicinity have become a great concern due to their persistency and toxicity. Polyurethane foam based passive air samplers (PUF-PAS) was deployed in order to screen the presence of short- and medium- chain chlorinated paraffins (SCCPs and MCCPs) in the outdoor atmosphere at many sites in India (in winter 2006) and Pakistan (in winter 2011). Concentrations of SCCPs and MCCPs ranged from not detected (ND) to 47.4 and 0 to 38.2 ng m(-3) with means of 8.11 and 4.83 ng m(-3), respectively. Indian concentrations showed higher average levels of both SCCPs and MCCPs India (10.2 ng m(-3) and 3.62 ng m(-3) than the samples from Pakistan (5.13 ng m(-3) and 4.21 ng m(-3)). Relative abundance patterns of carbon number are C10 > C11 > C12 similar to C13 for SCCPs and C14 > C15 > C16 C17 for MCCP with similarity to the profiles of samples from China, the biggest CPs producer in the world. Principal Component Analysis suggested that detected SCCPs and MCCPs in this study originated from the same emission source.Production and use of chlorinated paraffins (CPs) have been increasing in India. Distribution of CPs in the area and vicinity have become a great concern due to their persistency and toxicity. Polyurethane foam based passive air samplers (PUF-PAS) was deployed in order to screen the presence of short- and medium- chain chlorinated paraffins (SCCPs and MCCPs) in the outdoor atmosphere at many sites in India (in winter 2006) and Pakistan (in winter 2011). Concentrations of SCCPs and MCCPs ranged from not detected (ND) to 47.4 and 0 to 38.2 ng m(-3) with means of 8.11 and 4.83 ng m(-3), respectively. Indian concentrations showed higher average levels of both SCCPs and MCCPs India (10.2 ng m(-3) and 3.62 ng m(-3) than the samples from Pakistan (5.13 ng m(-3) and 4.21 ng m(-3)). Relative abundance patterns of carbon number are C10 > C11 > C12 similar to C13 for SCCPs and C14 > C15 > C16 C17 for MCCP with similarity to the profiles of samples from China, the biggest CPs producer in the world. Principal Component Analysis suggested that detected SCCPs and MCCPs in this study originated from the same emission source