Influence of water quality parameters on occurrence of polybrominated diphenyl ether in sediment and sediment to biota accumulation

Polybrominated diphenyl ether (PBDE) concentrations in sediment and fish from 12 principal rivers in Taiwan were investigated to determine their association with water quality parameters as well as the biota-sediment accumulation factor (BSAF) in fish with different living patterns. The highest PBDE concentration in sediment was found in the Bajhang River (261 ng g^?1 dry weight (d.w.)) and the lowest in the Beinan River and the Da-an River (0.17 ng g^?1 d.w.). The PBDE concentrations in fish samples ranged from 1.28 ng g^?1 d.w. (Oreochromis niloticus niloticus) in the Yanshuei River to 33.7 ng g^?1 d.w. (Varico rhinos barbatulus) in the Da-an River. We conclude that PBDEs contamination in sediment was significantly affected by NH₃–N, pH, and DO. The BSAF results showed a parabolic trend from low- to high-brominated BDEs. Fish easily accumulated the congeners BDE-47, -100, -119, -126, and -154 from sediment. The BSAF decreased in the following order: PeBDE > HxBDE > TeBDE > other BDEs. Principle component analysis showed that demersal fish have different PBDE sources than do pelagic fish. We conclude that living and feeding habits are critical factors affecting PBDE accumulation in fish.     

Dietary assessment of human exposure to PBDEs in South Korea

This study was conducted to measure the concentration of PBDEs in various food stuffs from Korea and to estimate levels of PBDE intake from food for the Korean population according to geographical location and age. 20 types of food samples were collected from four heavily populated cities (Seoul, Gwangju, Daejeon, Pusan) and one rural city (Gangneung) and were analyzed for 19 polybrominated diphenyl ether congeners (BDE 15, 17, 28, 33, 47, 49, 66, 71, 85, 99, 100, 119, 126, 138, 153, 154, 183, and 209).No significant differences in total PBDE levels in foods were found among four large cities (Gwangju; 10.91 ng g^?1 wet weight (ww), Seoul; 7.66 ng g^?1 ww, Daejeon; 6.91 ng g^?1 ww, Pusan; 6.87 ng g^?1 ww) and one rural city (Gangneung; 8.72 ng g^?1 ww). Daily dietary intake of PBDEs does not appear to be related to the extent of urbanization.Total dietary intake of PBDE for the average general population was 72.30 ng d^?1 (not detected (ND) = 0) which was similar to other countries. In all food groups, the largest contribution to PBDE intake was from fish and shellfish (48.96 ng d^?1). Total PBDE consumed per kilogram of body weight was estimated to range from 2.70 ng kg^?1 d^?1 for infants 1 through 2 years of age to 0.85 ng kg^?1 d for 65 years and older and was highest in young children and decreased with increasing age.     

Polychlorinated biphenyls hot and cold seasons distribution in see water,sediment, and fish samples in the Khour-e-Mousa (Mah-Shahr), Iran

The concentrations of polychlorinated biphenyls (PCBs) were assessed at four sites in Khour-e-Mousa (Mah-Shahr), Iran. Sea water, sediment and fish (cynoglossus bilineatus) samples were taken at each site and were analysed for PCB levels. To investigate the possible source of PCBs found in fish samples, sediments and waters were collected from four sites (D1, D2, D3, and D4) and studied. The relationship between PCB concentrations in sediment, water and fish is discussed. The results indicate that PCBs are detected in all fish samples and its concentration range from 3.2 to 102.7 μg kg^?1 dry weight and 5.4–149.7 μg kg^?1 dry weight in cold and warm seasons, respectively. The D2 and D4 sites were found to have the highest and lowest levels of PCB concentrations, respectively. Total congener PCB (CB, 28, 52, 44, 101, 149, 118, 153, 138, and 180) concentrations at the sediment samples for D1, D2, D3, and D4 sites ranged from 1.6 to 30.9 μg kg^?1 dry weight and 2.3–47.1 μg kg^?1 dry weight in cold and warm seasons, respectively. The total PCB concentrations for D2 site were found to be significantly higher than other three sites. Total water congener PCB (CB, 28, 52, 44, 101, 149, 118, 153, 138, and 180) concentrations ranged from 0.01 to 0.25 μg L^?1 and 0.02–0.39 μg L^?1 in cold and warm seasons, respectively.     

Bioaccumulation of polybrominated diphenyl ethers in harbor seals from the northwest Atlantic

Polybrominated diphenyl ethers (PBDEs) were analyzed in blubber of harbor seals (Phoca vitulina concolor) collected between 1991 and 2005 along the northwest Atlantic. ∑PBDE concentrations (mono- to hexa-BDEs) detected in blubber samples (n = 42) ranged from 80 to 25 720 ng g⁻¹ lw, (overall mean 2403 ± 5406 ng g⁻¹ lw). By age, mean ∑PBDE concentrations were: 3645 ± 7388, 2945 ± 5995, 1385 ± 1265, and 326 ± 193 ng g⁻¹ lw in pups, yearlings, adult males, and adult females, respectively. Unlike the trend for PCBs, no decreasing gradient from urban to rural/remote areas was observed for PBDEs in these samples, likely reflecting inputs from local sources. No significant temporal trend was observed for PBDEs in harbor seals between 1991 and 2005, although congener profiles shifted over time. Tetra-BDE-47 was the dominant congener, followed by BDEs-99, -100, -153, -154, and -155 in varying order, suggesting exposure to the penta-BDE product. In adult males, the hexa-BDEs contributed more to the total (22%) than BDEs-99 and -100 (14%), and concentrations of BDE-155 were elevated compared with -154. Higher BDEs were detected in a subset of seals (n = 12) including hepta-BDE-183, the marker for the octa-BDE mixture, and octa-BDE-197, along with several unidentified hepta- and octa- congeners. BDE-209 was detected in seal blubber at concentrations ranging from 1.1 to 8 ng g⁻¹ lw, indicating that deca-BDE is bioavailable in this marine food web. This is the first study to document the accumulation of BDE-209 at measurable levels in wild harbor seals. While the PBDE patterns in blubber indicate exposure to all three BDE commercial mixtures, the data also suggest that BDE-209 debromination by seal prey fish may contribute to the loading of lower brominated congeners (hexa- to octa-BDEs) in these seals.     

Polychlorinated biphenyls (PCBs) and Polybrominated Diphenyl ethers (PBDEs) in three fish species from an estuary in the southeastern coast of Brazil

Polychlorinated biphenyls (PCBs) and Polybrominated Diphenyls Ethers (PBDEs) are two highly lipophilic classes of persistent organic pollutants able to resist degradation and with the ability to bioaccumulate through the food chain. In Brazil, there are still few studies on PCBs and PBDEs in aquatic organisms. In this study, we determined the levels of PBDEs and PCBs in three different fish species from the Ilha Grande Bay, located in the southern state of Rio de Janeiro, Brazil. PBDEs levels were very low, with values below the limit of quantification. PCBs concentrations ranged from 2.29 to 27.60 ng g^?1 ww in muscle and from 3.41 to 34.22 ng g^?1 ww in liver of the three investigated fish species. Significant positive correlations were established between PCBs concentration and fish biometric variables in mullet (length and lipid content) and a statistically significant change between seasons in croaker was observed.     

Concentrations of organochlorine pesticides (OCPs) residues in foodstuffs collected from traditional markets in Indonesia

A total 23 of organochlorine pesticides (OCPs) residues were determined in five groups of foodstuffs, i.e.: vegetables (carrot, potato, cucumber, corn, and onion), rice, pulses (green bean and soybean), nuts (peanut), and fish (milkfish), which collected from traditional markets in three big cities of Indonesia; Jakarta, Bogor, and Yogyakarta. OCPs were only detected in fatty foodstuffs, such as soybean, peanut, and milkfish. The concentration of HCB (expressed as ng g^?1 on a whole basis), ΣDrins, ΣDDTs, ΣHeptachlors, and ΣHCHs were in the range of <0.3–0.74 ng g^?1, <0.03–0.42 ng g^?1, <0.02–0.41 ng g^?1, <0.03–0.14 ng g^?1, and <0.03–0.06 ng g^?1, respectively, which were far below the maximum residue limits (MRLs) as established by FAO/WHO. These very low concentrations of OCPs residues in foodstuffs indicated that OCPs were used only in past time and no recent input into the environment. Furthermore, the estimated daily intake (EDI) of HCB, ΣDDTs, ΣDrins, ΣHeptachlors, and ΣHCHs in five group foodstuffs, which were 60% of total daily diet of Indonesian, were 0.09 ng kg^?1 bw d^?1, 0.04 ng kg^?1 bw d^?1, 0.01 ng kg^?1 bw d^?1, 0.003 ng kg^?1 bw d^?1, and 0.002 ng kg^?1 bw d^?1, respectively. These results were far below the acceptable daily intake (ADI) as established by FAO/WHO, which indicated that consumption of foodstuffs from Indonesia were at little risk to human health in term of OCPs at present.     

High concentrations of persistent organic pollutants including PCBs,DDT, PBDEs and PFOS in little brown bats with white-nose syndrome in New York,USA

White-nose syndrome (WNS) is a condition associated with white fungal growth on ears, wings, and nose of hibernating bats; this condition has recently resulted in high bat mortality in the northeastern United States. Nevertheless, the pathogenesis of morbidity and mortality are still unknown. Elevated exposure to toxic contaminants could be a contributing factor via the consequent immunosuppression and endocrine disruption. In this study, diseased little brown bats (Myotis lucifugus) were collected from several hibernacula in eastern New York State in 2008. Fat tissues of bats were analyzed for polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs), and organochlorine pesticides (OCPs; DDT, chlordanes, HCB, and HCH), and liver was analyzed for perfluorinated compounds (PFCs). A reference population of little brown bats, not affected by WNS, was also collected from a cave in Kentucky for the analysis of trace organic contaminants. Concentration of PCBs in fat tissues of bats from New York ranged from 1900 ng g^?1 to 35 000 ng g^?1, lipid wt, with the highest concentrations found in bats collected from caves in Albany County. High concentrations of PCBs were also found in bats from Kentucky (17 100–18 400 ng g^?1, lipid wt). Total PBDE concentrations in fat tissues ranged from 520 ng g^?1 to 10 900 ng g^?1, lipid wt, in bats from New York and from 4300 ng g^?1 to 13 000 ng g^?1, lipid wt, in bats from Kentucky. High concentrations of DDT (26 900 ng g^?1, lipid wt), chlordanes (6350 ng g^?1, lipid wt), and HCB (260 ng g^?1, lipid wt) were found in bats from New York. Concentrations of hexabromobiphenyl congener 153 (PBB 153) in bats from New York ranged from 8.6 ng g^?1 to 12 4000 ng g^?1, lipid wt. Concentrations of PFCs were on the order of a few tens to a few hundreds of nanograms per gram liver, on a wet weight basis. Overall, high concentrations of PCBs, PBDEs, DDT, and chlordanes were found in fat tissues of diseased bats from New York, although the concentrations in bats from non-diseased, reference population, from Kentucky were also high.     

Air–water exchange fluxes of polycyclic aromatic hydrocarbons in the tropical coast,Taiwan

Air–water exchange fluxes of polycyclic aromatic hydrocarbons (PAHs) were simultaneously measured in air and water samples from two sites on the Kenting coast, located at the southern tip of Taiwan, from January to December 2010. There was no significant difference in the total PAH (t-PAH) concentrations in both gas and dissolved phases between these two sites due to the less local input which also coincided to the low levels of t-PAH concentration; the gas and dissolved phases averaged 1.29 ± 0.59 ng m^?3 and 2.17 ± 1.19 ng L^?1 respectively. The direction and magnitude of the daily flux of PAHs were significantly influenced by wind speed and dissolved PAH concentrations. Individual PAH flux ranged from 627 ng m^?2 d^?1 volatilization of phenanthrene during the rainy season with storm–water discharges raising dissolved phase concentration, to 67 ng m^?2 d^?1 absorption of fluoranthene during high wind speed periods. Due to PAH annual fluxes through air–water exchange, Kenting seawater is a source of low molecular weight PAHs and a reservoir of high molecular weight PAHs. Estimated annual volatilization fluxes ranged from 7.3 μg m^?2 yr^?1 for pyrene to 50 μg m^?2 yr^?1 for phenanthrene and the absorption fluxes ranged from ?2.6 μg m^?2 yr^?1 for chrysene to ?3.5 μg m^?2 yr^?1 for fluoranthene.     

Comprehensive assessment of pine needles as bioindicators of PAHs using multivariate analysis. The importance of temporal trends

The importance of the annual and seasonal trends associated to the polycyclic aromatic hydrocarbons (PAHs) biomonitoring by pine needles are studied with a comprehensive use of univariate and multivariate analysis tools. For this purpose, four pine needle sampling campaigns (winter, spring, summer and autumn 2007) were carried out in 29 sites from Portugal. Needles from Pinus pinaster Ait. and Pinus pinea L. trees were collected from all year-classes available in each tree, corresponding to the different shoots of needles coming out every spring and the results of both species were treated separately. Annual trends of polycyclic aromatic hydrocarbons (PAHs) contamination indicate a general increase from the least to the most exposed year-classes, for all seasons. The mean values for the sum of 16 PAHs ranged from 71 ± 33 ng g⁻¹ (dry weight – dw) for new year (2007) needles in the summer to 514 ± 317 ng g⁻¹ (dw) for 2-year needles (2005) in the spring for P. pinea, and between 90 ± 50 ng g⁻¹ (dw) for new year (2007) needles in the summer and 1212 ± 436 ng g⁻¹ (dw) for 3-year needles (2004) in summer for P. pinaster. The seasonal evolution shows the highest concentrations in the winter, then declining to the lowest levels in the summer and rising again from summer to autumn. Principal component analysis confirmed differences between seasons and needle year-classes, more visible for P. pinea samples. The cooler seasons have more affinity towards the lighter more abundant PAHs, as do the older needles. Differences between both pine species are also evident.     

Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) in biosolids from municipal wastewater treatment plants in China

Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) along with methoxylated polybrominated diphenyl ethers (MeO-PBDEs) have been frequently identified as natural compounds in marine environment and also assumed as metabolites of PBDEs. In the present study, nine OH-PBDE, nine MeO-PBDE and 10 PBDE congeners were studied in the sewage sludge collected from 36 municipal wastewater treatment plants (WWTPs) in 27 cities of China. The results suggest that OH-PBDEs and PBDEs are ubiquitous in sewage sludge in China, however, methoxylated PBDEs were not detectable. Composition profiles of detected OH-PBDE congeners were different depending on the sampling location. ΣOH-PBDEs in WWTPs sludge ranged from 0.04 to 2.24 ng g^?1 dry weight (mean: 0.35 ng g^?1 dry weight). The total amount of the two most prominent congeners (6-OH-BDE-47 + 2′-OH-BDE-68) accounted for about 53.3–100% of the sum of all six identified congeners. A significant linear relationship was found between 6-OH-BDE-47 and 2′-OH-BDE-68. A distinct geographical distribution of ΣOH-PBDEs was observed with greater concentrations of OH-PBDEs at coastal areas than inland regions in China.     

Measurement of the vapor phase deposition of polychlorinated bipheyls (PCBs) using a water surface sampler

A water surface sampler (WSS) was employed in combination with greased knife-edge surface deposition plates (KSSs) to measure the vapor phase deposition rates of PCBs to the sampler at an urban site, Chicago, IL. This sampler employed a water circulation system that continuously removed deposited PCBs. Total (gas+particle) and particulate PCB fluxes were collected with the WSS and KSSs, respectively. Gas phase PCB fluxes were then calculated by subtracting the KSS fluxes (particulate) from the WSS fluxes (gas+particle). The calculated gas phase PCB fluxes averaged 830±910 ng m⁻²d⁻¹. This flux value is, in general, higher than the fluxes determined using simultaneously measured air–water concentrations in natural waters and is in the absorption direction. This difference is primarily because the PCBs were continuously removed from the WSS water keeping the water PCB concentration near zero.Concurrently, ambient air samples were collected using a modified high volume air sampler. The gas phase PCB concentrations ranged between 1.10 and 4.46 ng m⁻³ (average±SD, 2.29±1.28 ng m⁻³). The gas phase fluxes were divided by the simultaneously measured gas phase ambient concentrations to determine the overall gas phase mass transfer coefficients (MTCs) for PCBs. The average gas phase overall MTCs (K_g) for each homolog group ranged between 0.22 and 1.32 cm s⁻¹ (0.54±0.47 cm s⁻¹). The average MTC was in good agreement with those determined using similar techniques.     

Atmospheric deposition of organochlorine contaminants to Galveston Bay,Texas

Atmospheric monitoring of PCBs and chlorinated pesticides (e.g., HCHs, chlordanes, and DDTs) in Galveston Bay was conducted at Seabrook, Texas. Air and wet deposition samples were collected from 2 February 1995 and continued through 6 August 1996. Vapor total PCB (tPCB) concentrations in air ranged from 0.21 to 4.78 ng m⁻³ with a dominance of tri-chlorinated PCBs. Dissolved tPCBs in rain ranged from 0.08 to 3.34 ng l⁻¹, with tetra-chlorinated PCBs predominating. The predominant isomers found in air and rain were α- and γ-HCH, α- and γ-chlordanes, 4,4′-DDT, and dieldrin. The concentrations of PCBs and pesticides in the air and rain revealed no clear seasonal trend. Elevated levels of PCBs in the air occurred when temperatures were high and wind came from urban and industrialized areas (S, SW, NW, and W of the site). Concentrations of HCHs were elevated in April, May, and October, perhaps due to local and/or regional applications of γ-HCH (lindane). Other pesticides showed no notable temporal variation. When winds originated from the Gulf of Mexico (southeasterly), lower concentrations of organochlorines were detected in the air. The direct deposition rate (wet+dry) of PCBs to Galveston Bay (6.40 μg m⁻² yr⁻¹) was significantly higher than that of pesticides by a factor of 5–10. The net flux from gas exchange estimated for PCBs was from Galveston Bay water to the atmosphere (78 μg m⁻² yr⁻¹). Gas exchange of PCBs from bay water to the atmosphere was the dominant flux.     

Polybrominated diphenyl ethers and their methoxylated and hydroxylated analogs in Brown Bullhead (Ameiurus nebulosus) plasma from Lake Ontario

Polybrominated diphenyl ethers (PBDEs), methoxylated PBDEs (MeO-PBDEs) and hydroxylated PBDEs (OH-PBDEs) were detected and quantified in Brown Bullhead (Ameiurus nebulosus) from Lake Ontario. Samples were collected in 2006 from three different locations near the city of Toronto: Frenchman’s Bay, Toronto Island, and Tommy Thompson Park. A total of 117 plasma samples were pooled into 19 samples, separating males and females by site of capture. Pooled samples were analyzed for 36 PBDEs, 20 MeO-PBDEs and 20 OH-PBDEs, but only six PBDEs, five MeO- and eight OH-compounds were confirmed against standards currently available. These peaks were quantified as “identified” peaks, while peaks matching ion ratios but not matching the retention time of the available standards were quantified as “unidentified” peaks. Both “identified” and “unidentified” concentrations were combined to obtain a total concentration. No significant variations were obtained for total PBDE concentrations, ranging from 3.33 to 9.02 ng g^?1 wet weight. However, OH- and MeO-PBDE totals ranged over 1 order of magnitude among the samples (not detected – 3.57 ng g^?1 wet weight for OH-PBDEs and not detected ?0.10 ng/g wet weight for MeO-PBDE). The results of this study suggested that these compounds are ubiquitous in biota. Source estimation of MeO- and OH-PBDEs in freshwater fish were discussed. Considering that up to date no freshwater sources for MeO- or OH-PBDEs have been reported, concentrations found should be mainly related to bioaccumulation from anthropogenic sources, although other sources could not be dismissed.     

Organochlorine pesticides and polychlorinated biphenyls in soil and water samples in the Northeastern part of São Paulo State,Brazil

Detailed analyses of persistent organic pollutants (POPs) such as organochlorine pesticides (OCPs), hexachlorocyclohexane (HCH) isomers (HCHs), dichlorodiphenyltrichloro ethane (DDT) and its metabolites (DDTs) and congeners of polychlorinated biphenyls (PCBs) in soil and surface water from the northeastern São Paulo, Brazil allowed the evaluation of the contamination status, distribution and possible pollution sources. The pesticides and PCBs demonstrated markedly different distributions, reflecting different agricultural, domestic and industrial usage in each region studied. The ranges of HCH, DDT, and PCBs concentrations in the soil samples were 0.05–0.92, 0.12–11.01, 0.02–0.25 ng g⁻¹ dry wt, respectively, and in the surface water samples were 0.02–0.6, 0.02–0.58 and 0.02–0.5 ng l⁻¹, respectively. Overall elevated levels of DDT and PCB were recorded in region 2, a site very close to melting, automotive batteries industries, and agricultural practice regions. High ratios of metabolites of DDT to DDT isomers revealed the recent use of DDT in this environment. The sources of contamination are closely related to human activities, such as domestic and industrial discharge, street runoff, agricultural pesticides and soil erosion, due to deforestation as well as atmospheric transport.     

Persistent organochlorine pesticide and PCB residues in surface sediments of Lake Qarun,a protected area of Egypt

Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were determined in sediment samples collected from 34 locations in Lake Qarun, Egypt to elucidate their concentrations, distribution, possible sources and potential ecological risk. A total of 25 OCPs and 29 PCBs were identified and quantified. OCPs and PCBs were found to be ubiquitous pollutants in the aquatic environment of Lake Qarun, particular near urban areas reflecting the local usage and input of these pollutants. Total concentrations of OCPs and PCBs in sediments ranged from 1.01 to 164.8 ng g^?1 and 1.48 to 137.2 ng g^?1, respectively. Among OCPs, γ-HCH, heptachlor, aldrin, endrin, p,p′-DDE, oxy-chlordane and endosulfan I and II were the most abundant compounds. The composition of PCB congeners was dominated by the tri-, tetra-, penta- and hexa-chlorinated biphenyls. The ratios of certain metabolites (isomers) to their parent compounds (mixtures) indicated there are still new inputs of lindane, endrin, heptachlor and technical endosulfan to Qarun Lake, while the ratios of (p,p′-DDE + p,p′-DDD)/∑p,p′-DDTs indicate earlier usage of DDT. Contamination levels of PCBs and HCHs can be categorized as moderate to high compared to other urbanized regions worldwide. According to established sediment quality guidelines, γ-HCH, endrin and chlordanes would be more concerned OCP species for the ecotoxicological risk in Lake Qarun.     

Comparison of organic compositions in dust storm and normal aerosol samples collected at Gosan,Jeju Island,during spring 2005

To better understand the current physical and chemical properties of East Asian aerosols, an intensive observation of atmospheric particles was conducted at Gosan site, Jeju Island, South Korea during 2005 spring. Total suspended particle (TSP) samples were collected using pre-combusted quartz filters and a high-volume air sampler with the time intervals ranging from 3 h to 48 h. The kinds and amount of various organic compounds were measured in the samples using gas chromatography–mass spectrometry. Among the 99 target compounds detected, saccharides (average, 130 ± 14 ng m^?3), fatty acids (73 ± 7 ng m^?3), alcohols (41 ± 4 ng m^?3), n-alkanes (32 ± 3 ng m^?3), and phthalates (21 ± 2 ng m^?3) were found to be major compound classes with polyols/polyacids, lignin and resin products, PAHs, sterols and aromatic acids being minor. Compared to the previous results reported for 2001 late spring samples, no significant changes were found in the levels of their concentrations and compositions for 4 years, although the economy in East Asia, especially in China, has sharply expanded from 2001 to 2005. During the campaign at Gosan site, we encountered two distinct dust storm episodes with high TSP concentrations. The first dust event occurred on March 28, which was characterized by a predominance of secondary organic aerosols. The second event that occurred on the next day (March 29) was found to be characterized by primary organic aerosols associated with forest fires in Siberia/northeastern China. A significant variation in the molecular compositions, which was found within a day, suggests that the compositions of East Asian aerosols are heterogeneous due to multi-contributions from different source regions together with different pathways of long-range atmospheric transport of particles.     

Atmospheric distribution of polycyclic aromatic hydrocarbons and deposition to Galveston Bay,Texas, USA

Estimates of the atmospheric deposition to Galveston Bay of polycyclic aromatic hydrocarbons (PAHs) are made using precipitation and meteorological data that were collected continuously from 2 February 1995 to 6 August 1996 at Seabrook, TX, USA. Particulate and vapor phase PAHs in ambient air and particulate and dissolved phases in rain samples were collected and analyzed. More than 95% of atmospheric PAHs were in the vapor phase and about 73% of PAHs in the rain were in the dissolved phase. Phenanthrene and napthalene were the dominant compounds in air vapor and rain dissolved phases, respectively, while 5 and 6 ring PAH were predominant in the particulate phase of both air and rain samples. Total PAH concentrations ranged from 4 to 161 ng m⁻³ in air samples and from 50 to 312 ng l⁻¹ in rain samples. Temporal variability in total PAH air concentrations were observed, with lower concentrations in the spring and fall (4–34 ng m ⁻³) compared to the summer and winter (37–161 ng m⁻³). PAHs in the air near Galveston Bay are derived from both combustion and petroleum vaporization. Gas exchange from the atmosphere to the surface water is estimated to be the major deposition process for PAHs (1211 μg m^{− 2} yr^{− 1}), relative to wet deposition (130 μg m⁻² yr^{− 1}) and dry deposition (99 μg m⁻² yr^{− 1}). Annual deposition of PAHs directly to Galveston Bay from the atmosphere is estimated as 2  t yr⁻¹.     

Hexabromocyclododecanes in surface sediments and a sediment core from Rivers and Harbor in the northern Chinese city of Tianjin

In the present study, hexabromocyclododecanes (HBCDs) were investigated in the sediment from Haihe River (HR), Dagu Dainage Canal (DDC) and Tianjin Harbor (TH) at Bohai Bay using a total of 51 samples of surface sediments and a sediment core collected from May to September in 2010, and its diastereomer- and enantiomer-specific profiles were analyzed. The concentration of total HBCDs were generally high, with mean value and ranges of 31.0 and 1.35–634 ng g^?1 dw, respectively. The contamination followed the order of TH > DDC > HR. Higher levels (up to 634 ng g^?1 dw) occurred in the lower reach of HR and DDC located in an industrial area of Tianjin. This is the first time to report so high concentration of HBCDs in sediment in Southeast Asia. The γ-diastereomer dominated in most samples (44 out of 51), and this is in agreement with the diastereomer distribution pattern in industrial products, while α-HBCD was the dominant diastereomer in the other seven samples. However, only few samples exhibited γ-diastereomer ratio similar to that (75–89%) in technical products, indicating the inter-transformation and variable degradation of the different isomers. The high ratio of γ-diastereomer could be used as an indicator for fresh contamination input. Enantiomeric factors (EFs) of HBCD isomers in most of the samples were statistically different from technical products (p < 0.05), showing a trend of more easily enrichment of the (?)-HBCD-enantiomer compared to the (+)-HBCD-enantiomer. The δ- and ε-diastereomers were frequently detected but at low level. The HBCDs in the sediment core showed several peaks, and the greatest value occurred in 2005, when a plastic manufacture plant using HBCD was set up nearby.     

Speciated mercury in size-fractionated particles in Shanghai ambient air

Size-fractionated particles were collected at two sites from July 2004 to April 2006 in Shanghai. The mercury in particles was extracted and divided operationally into four species: exchangeable particulate mercury (EXPM), HCl-soluble particulate mercury (HPM), elemental particulate mercury (EPM) and residual particulate mercury. The total particulate Hg concentration during the study period ranged from 0.07 ng m^?3 to 1.45 ng m^?3 with the average 0.56 ± 0.22 ng m^?3 at site 1, while 0.20 ng m^?3–0.47 ng m^?3 with the average 0.33 ± 0.09 ng m^?3 at site 2, which is far higher than some foreign cities and comparable to some cities with heavy air pollution in China. The Hg mass content also displayed evident size distribution, with higher value in PM_1.6–3.7, somewhat higher or lower than the source profile. EXAM was only found in the summer, HPM have higher percentage in summer and fall rather than in winter and spring. The different mercury species showed different correlation to temperature, relative humidity, wind speed. HPM positively depends on temperature at both sites which implies the importance of mercury transformation on particles. In foggy days TPM increased greatly, but HPM didn't vary greatly as anticipated. Instead, RPM gained a distinguished increase. It demonstrated that aqueous reaction and complex heterogenic reactions in droplet might happen in acidic environment. The correlation of mercury with other pollutants including SO₂, NO₂, CO and PM₁₀ varies with the different mercury forms. Hybrid single-particle lagrangian integrated trajectories (HYSPLIT) model was used to back trace air mass at different representative days and results indicated that transportation from Huabei Plain will increase mercury concentration in winter and fall to some extent. The possible existing compounds and their atmospheric behavior of HPM, EPM and RPM were calculated and the compared to analyze its implication on atmospheric mercury cycle.     

Triclosan in individual human milk samples from Australia

Triclosan is a chlorinated phenol ether that has been in widespread use as a broad-spectrum antibacterial agent for four decades. When compared to the limited international data available on human body burden of triclosan, results from a pooled blood study suggested that triclosan concentrations in Australia were a factor two higher than observed in Sweden. This study determined triclosan levels in individual human milk samples (n = 151) collected between 2002 and 2005 from primiparous Australian mothers. It provided the first report of population triclosan levels and individual variation in Australia and gave a measure of infant exposure via breast feeding. The distribution of triclosan concentration was positively skewed, with 7.2% of the samples below the LOQ, 66% with a concentration of less than or equal to 1.0 ng g⁻¹ fresh weight and the remaining samples above 1 ng g⁻¹ reaching a maximum concentration of 19 ng g⁻¹ fresh weight. The mean and median triclosan concentrations were 1.3 ± 2.7 ng g⁻¹ f.w. and 0.26 ng g⁻¹ f.w., respectively. The results of this study showed high variability in triclosan concentrations between individuals and no correlations with maternal age (p = 0.094), maternal weight (p = 0.971) or infant age at the time of sample collection (p = 0.621). A large number of samples contained low or non-quantifiable concentrations of triclosan and so, in Australia, ubiquitous background exposure due to environmental sources is low. This means that body burden can be influenced by an individual’s use of triclosan containing product. Given that triclosan containing product use is continuing, it is important that monitoring in both humans and the environment is continued and that triclosan containing products are adequately labeled so that an individual can choose to avoid exposure.