Polybrominated diphenyl ethers (PBDEs) and indicator polychlorinated biphenyls (PCBs) in marine fish from four areas of China

The levels of polybrominated diphenyl ethers (PBDEs) and indicator polychlorinated biphenyls (PCBs) were determined in marine fish from four areas of China (South China Sea, Bohai Sea, East China Sea, and Yellow Sea) using GC/NCI-MS and GC/ITMS, respectively. Total concentrations of eight PBDEs (BDE-28, 47, 99, 100, 153, 154, 183 and 209) in all samples ranged from 0.3 ng g⁻¹ ww (wet weight) to 700 ng g⁻¹ ww, with median and mean values of 85 ng g⁻¹ ww and 200 ng g⁻¹ ww, respectively. BDE-209 and BDE-47 were the major congeners in all samples, contributing 54% and 19% to the total concentration, respectively. The sum of seven indicator PCB levels (CB-28, 52, 101, 118, 138, 153, and 180) ranged from 0.3 ng g⁻¹ ww to 3.1 μg g⁻¹ ww, with median and mean values of 6.4 ng g⁻¹ ww and 398 ng g⁻¹ ww, respectively. High contributions of CB-138 (32%) and CB-153 (25%) were found in all samples. In general, pollutants measured in this study were at high levels when compared with previous studies from other regions in the world. The relative abundance of BDE-209 may suggest that deca-BDE sources existed in studied area. And principal component analysis (PCA) showed that there were other PBDE sources in Yellow Sea. The pattern and PCA showed that PCB pollutions came from similar sources in the studied areas. In addition, concentrations of ∑₇PBDEs (u/209) were strongly correlated with those of ∑₇PCBs in all fish (r = 0.907, n = 44).     

Removal of tetrabromobisphenol A by conventional activated sludge, submerged membrane and membrane aerated biofilm reactors

The goal of this study was to compare removal efficiencies of tetrabromobisphenol A (TBBPA) using typical wastewater treatment technologies, and to identify the most significant mechanisms of removal. Two types of municipal wastewater reactors were studied: a full-scale conventional activated sludge (CAS) reactor with tertiary treatment; and three pilot-scale membrane bioreactors (MBRs) having different sludge retention times (SRTs). All four reactors were fed the same influent. A third reactor type, a membrane aerated biofilm reactor (MABR) was fed tap water, ammonia, and TBBPA. TBBPA in municipal influent ranged from 1 to 41 ng L⁻¹ (n = 10). The CAS effluent had an average TBBPA concentration of 0.7 ± 1.3 ng L⁻¹ (n = 3). Effluent concentrations from the MBRs were an average of 6 ± 6 ng L⁻¹ TBBPA (n = 26). Significant TBBPA removal was observed in the MABR throughout the 5 week of study (p ? 0.05). Removal of TBBPA from wastewater treatment was found to be due to a combination of adsorption and biological degradation. Based on experimental results, nitrification is likely a key process therein. No significant relationship between removal of TBBPA and SRT was identified (p ? 0.05).     

Simultaneous determination of organochlorine pesticides and bisphenol A in edible marine biota by GC-MS

A study to assess the level of organochlorine pesticides (OCPs) and bisphenol A (BPA) in edible marine biota collected from coastal waters of Malaysia was conducted using GC-MS and SPE extraction. An analytical method was developed and validated to measure the level of 15 OCPs and BPA simultaneously from five selected marine species. It was observed that some samples had low levels of p,p′-DDE, p,p′-DDT and p,p′- DDD ranging from 0.50 ng g⁻¹ to 22.49 ng g⁻¹ dry weight (d.w) but significantly elevated level of endosulfan I was detected in a stingray sample at 2880 ng g⁻¹ d.w. BPA was detected in 31 out of 57 samples with concentration ranging from below quantification level (LOQ: 3 ng g⁻¹) to 729 ng g⁻¹ d.w. The presence of OCPs is most likely from past use although there is also indication of illegal use in recent times. The study also reveals that BPA is more widely distributed in coastal species caught off the coast of the most developed state. The potential health risk from dietary intakes of OCPs and BPA from the analysed fish species was negligible.     

Using native epiphytic ferns to estimate the atmospheric mercury levels in a small-scale gold mining area of West Java, Indonesia

Mercury pollution is caused by artisanal and small-scale gold mining (ASGM) operations along the Cikaniki River (West Java, Indonesia). The atmosphere is one of the primary media through which mercury can disperse. In this study, atmospheric mercury levels are estimated using the native epiphytic fern Asplenium nidus complex (A. nidus) as a biomonitor; these estimates shed light on the atmospheric dispersion of mercury released during mining.Samples were collected from 8 sites along the Cikaniki Basin during September-November, 2008 and September-November, 2009.The A. nidus fronds that were attached to tree trunks 1-3 m above the ground were collected and measured for total mercury concentration using cold vapor atomic absorption spectrometry (CVAAS) after acid-digestion. The atmospheric mercury was collected using porous gold collectors, and the concentrations were determined using double-amalgam CVAAS.The highest atmospheric mercury concentration, 1.8 × 10³ ± 1.6 × 10³ ng m⁻³, was observed at the mining hot spot, and the lowest concentration of mercury, 5.6 ± 2.0 ng m⁻³, was observed at the remote site from the Cikaniki River in 2009. The mercury concentrations in A. nidus were higher at the mining village (5.4 × 10³ ± 1.6 × 10³ ng g⁻¹) than at the remote site (70 ± 30 ng g⁻¹). The distribution of mercury in A. nidus was similar to that in the atmosphere; a significant correlation was observed between the mercury concentrations in the air and in A. nidus (r = 0.895, P < 0.001, n = 14). The mercury levels in the atmosphere can be estimated from the mercury concentration in A. nidus using a regression equation: log (Hg_A.nidu/ng g⁻¹) = 0.740 log (Hg_Air/ng m⁻³) − 1.324.     

Assessment of risk to humans of bisphenol A in marine and freshwater fish from Pearl River Delta, China

Bisphenol A (BPA) is a high production-volume chemical used in the manufacture of a wide variety of consumer products. However it is also a ubiquitous contaminant that can interfere with endocrine systems of wildlife and humans. China is the “world factory” and the Pearl River Delta is the major manufacturing center and is consequently polluted. Concentrations of BPA in meats of marketable fish had not been previously reported for this region. In the study upon which we report here concentrations of BPA were determined in 20 common species of freshwater and marine fish, collected from markets in Hong Kong, SAR, China. A comprehensive analytical method based on SPE extraction and liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) was developed, validated and applied. The method limit of detection (LOD) and limit of quantification (LOQ) were 0.5 and 1.25 ng g⁻¹ dw, respectively. BPA was detected in 19 species of fish at concentrations, ranging from 0.5 to 2.0 ng g⁻¹ ww. Average daily BPA intake per person ranged from 1.1 × 10² ng d⁻¹ for marine fish and 2.2 × 10² ng d⁻¹ for freshwater fish. Concentrations of BPA in fish from Hong Kong markets unlikely would be causing adverse population-level effects in humans.     

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.     

Mercury levels and trends (1993-2009) in bream (Abramis brama L.) and zebra mussels (Dreissena polymorpha) from German surface waters

Mercury concentrations have been analysed in bream (Abramis brama L.) and zebra mussels (Dreissena polymorpha) collected at 17 freshwater sites in Germany from 1993-2009 and 1994-2009, respectively, within the German Environmental Specimen programme. Mercury concentrations in bream ranged from 21 to 881 ng g⁻¹ wet weight with lowest concentrations found at the reference site Lake Belau and highest in fish from the river Elbe and its tributaries. Statistical analysis revealed site-specific differences and significant decreasing temporal trends in mercury concentrations at most of the sampling sites. The decrease in mercury levels in bream was most pronounced in fish from the river Elbe and its tributary Mulde, while in fish from the river Saale mercury levels increased. Temporal trends seem to level off in recent years. Mercury concentrations in zebra mussels were much lower than those in bream according to their lower trophic position and varied by one order of magnitude from 4.1 to 42 ng g⁻¹ wet weight (33-336 ng g⁻¹ dry weight). For zebra mussels, trend analyses were performed for seven sampling sites at the rivers Saar and Elbe of which three showed significant downward trends. There was a significant correlation of the geometric mean concentrations in bream and zebra mussel over the entire study period at each sampling site (Pearson’s correlation coefficient = 0.892, p = 0.00002). A comparison of the concentrations in bream with the environmental quality standard (EQS) of 20 ng g⁻¹ wet weight set for mercury in biota by the EU showed that not a single result was in compliance with this limit value, not even those from the reference site. Current mercury levels in bream from German rivers exceed the EQS by a factor 4.5-20. Thus, piscivorous top predators are still at risk of secondary poisoning by mercury exposure via the food chain. It was suggested focusing monitoring of mercury in forage fish (trophic level 3 or 4) for compliance checking with the EQS for biota and considering the age dependency of mercury concentrations in fish in the monitoring strategy.     

Persistent organic pollutants in plastic marine debris found on beaches in San Diego, California

Plastic debris were collected from eight beaches around San Diego County, California. Debris collected include: pre-production pellets and post-consumer plastics including fragments, polystyrene (PS) foam, and rubber. A total of n = 2453 pieces were collected ranging from <5 mm to 50 mm in size. The plastic pieces were separated by type, location, and appearance and analyzed for polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT) and its breakdown products, and chlordanes. PAH concentrations ranged from 30 ng g⁻¹ to 1900 ng g⁻¹, PCBs from non-detect to 47 ng g⁻¹, chlordanes from 1.8 ng g⁻¹ to 60 ng g⁻¹, and DDTs from non-detect to 76 ng g⁻¹. Consistently higher PAH concentrations found in PS foam samples (300-1900 ng g⁻¹) led us to examine unexposed PS foam packaging materials and PS virgin pellets. Unexposed PS foam contained higher concentrations of PAHs (240-1700 ng g⁻¹) than PS virgin pellets (12-15 ng g⁻¹), suggesting that PAHs may be produced during manufacturing. Temporal trends of debris were investigated at one site, Ocean Beach, where storm events and beach maintenance were found to be important variables influencing debris present at a given time.     

Levels of organochlorine pesticides and polychlorinated biphenyls in the critically endangered Iberian lynx and other sympatric carnivores in Spain

Accumulation of organochlorine compounds is well studied in aquatic food chains whereas little information is available from terrestrial food chains. This study presents data of organochlorine levels in tissue and plasma samples of 15 critically endangered Iberian lynx (Lynx pardinus) and other 55 wild carnivores belonging to five species from three natural areas of Spain (Doñana National Park, Sierra Morena and Lozoya River) and explores their relationship with species diet. The Iberian lynx, with a diet based on the consumption of rabbit, had lower PCB levels (geometric means, plasma: <0.01 ng mL⁻¹, liver: 0.4 ng g⁻¹ wet weight, fat: 87 ng g⁻¹ lipid weight) than other carnivores with more anthropic and opportunistic foraging behavior, such as the red fox (Vulpes vulpes; plasma: 1.11 ng mL⁻¹, liver: 459 ng g⁻¹, fat: 1984 ng g⁻¹), or with diets including reptiles at higher proportion, such as the Egyptian mongoose (Herpestes ichneumon; plasma: 7.15 ng mL⁻¹, liver: 216 ng g⁻¹, fat: 540 ng g⁻¹), or the common genet (Genetta genetta; liver: 466 ng g⁻¹, fat: 3854 ng g⁻¹). Chlorinated pesticides showed interspecific variations similar to PCBs. Organochlorine levels have declined since the 80s in carnivores from Doñana National Park, but PCB levels are still of concern in Eurasian otters (Lutra lutra; liver: 3873-5426 ng g⁻¹) from the industrialized region of Madrid.     

Historical trends in human dietary intakes of endosulfan and toxaphene in China, Korea and Japan

Recently, the Stockholm Convention prohibited the use of toxaphene and has been reviewing endosulfan. The historical use of these pesticides may contaminate food and tend to accumulate in the food chain. In this study, to evaluate the spatial and temporal trends of food contamination, the endosulfan and toxaphene levels were measured in pooled 24-h food composite samples from Chinese (n = 10), Korean (n = 10) and Japanese (n = 40) adults in the 1990s and 2007-2009. Endosulfan was detected in 32 of 40 samples from Japan, but its levels (sum of α- and β-isomers) were low in both the 1990s and 2009 (range as geometric mean (geometric standard deviation) [GM (GSD)]: 0.96 (1.6)-1.42 (1.4) ng kg⁻¹ d⁻¹). The dietary intakes of endosulfan in Seoul as GM (GSD) were 38.68 (1.3) ng kg bw⁻¹ d⁻¹ in 1994 and 92.17 (4.4) ng kg bw⁻¹ d⁻¹ in 2007, and significantly higher than those in Japan (p < 0.05). The samples from Beijing showed a 50-fold increase in the endosulfan levels from 1993 (GM: 0.58 ng kg⁻¹ d⁻¹) to 2009 (GM: 24.91 ng kg bw⁻¹ d⁻¹) (p < 0.05). Toxaphene was detected in 33 of 40 samples from Japan. The dietary intake of toxaphene in Japan (sum of Parlars #26, #50 and #62) was 0.32-1.21 ng kg bw⁻¹ d⁻¹ (range as geometric mean) and no temporal trend was observed. The dietary intake of toxaphene in Seoul increased significantly from 0.2 ng kg bw⁻¹ d⁻¹ (GM) in 1994 to 3.6 ng kg bw⁻¹ d⁻¹ (GM) in 2007 (p < 0.05). Only one of 10 pooled samples from Beijing contained a detectable level of toxaphene (0.3 ng kg bw⁻¹ d⁻¹). For the entire population, the risk of adverse health effects from dietary intakes of endosulfan and toxaphene is unlikely. However, the concentrations of endosulfan in several samples exceeded 10% of the acceptable daily intake limit value of 6 μg kg bw⁻¹ d⁻¹ set by the World Health Organization (WHO). It appears important to refine dietary intake estimates targeting food types and source identification to ensure safe food for consumers.     

Accumulation of organochlorine contaminants in loggerhead sea turtles, Caretta caretta, from the eastern Adriatic Sea

We analyzed 15 polychlorinated biphenyls (PCBs) and five organochlorine pesticides (OCPs) in fat tissue of 27 loggerhead sea turtles (Caretta caretta) from eastern Adriatic Sea with the curved carapace length ranging from 25.0 to 84.5 cm. The PCB profile was dominated by hexa- and hepta-chlorinated congeners, with PCB-153 (median: 114.9 ng g⁻¹ wet mass), PCB-138 (80.0 ng g⁻¹ w.m.), and PCB-180 (26.7 ng g⁻¹ w.m.) detected with the highest levels. Toxic mono-ortho congeners PCB-118, PCB-105 and PCB-180 with dioxin-like toxicity were found in >70% samples. 4,4′-DDE (81.0 ng g⁻¹ w.m.) prevailed the OCP signature, accounting for 80% of the total DDTs. A significant increasing trend in accumulation with size was found for PCB-52 (r_s = 0.512, p < 0.01) and PCB-114 (r_s = 0.421, p < 0.05). Comparison of our results with organochlorine contaminant (OC) pattern in some prey taxa suggest that contamination occurs primarily through the food web, with biomagnification factors of 0.14-6.99 which were positively correlated with the octanol-water partition coefficient (log K_ow; p < 0.05). This study, based upon a fairly large sample size collected mostly from incidentally captured animals over a short time period (June 2001-November 2002), present a temporal snapshot of OC contamination in wild, free-ranging loggerheads from Adriatic feeding grounds and provide a baseline for monitoring the regional OC trends in this endangered species.     

Persistent organic pollutants in food items collected in Hong Kong

This study aims to investigate levels of POPs in meat, edible oils, nuts, milk and wine collected from Hong Kong. Naphthalene, pp-DDE, beta-, gamma-HCH and PBDE 47 were detected in most of the food items. Goose liver accumulated the highest PAHs (47.9 ng g⁻¹ wet wt), DDTs (25.6), HCHs (13.0), PCBs (4.17), PBDEs (468 pg g⁻¹ wet wt) among all the selected food. Meat and nut groups had significant (p < 0.01 or 0.05) correlations between lipid contents and concentrations of PAHs (meat: r = 0.878), HCHs (meat: r = 0.753), DDTs (meat: r = 0.937; nuts: r = 0.968) and PCBs (meat: r = 0.832; nut: r = 0.946). The concentrations of DDTs, HCHs and PCBs in vegetable oil were lower, but HCHs in fish oil were higher, when compared with other countries. The concentrations of PAHs, DDTs, PCBs and PBDEs in food tested in the present study were all below various safety guidelines.     

Diastereoisomer- and enantiomer-specific determination of hexabromocyclododecane in fish oil for food and feed

Fish oils are one of the main sources of ω-3 fatty acids. However, they can present elevated levels of some lipophilic pollutants, such as hexabromocyclododecanes (HBCDs). Since data about HBCDs in fish oil samples are very limited, in this study, 25 samples of fish oil for feed and food have been analyzed. Total HBCDs, as well as, α-, β- and γ-diastereoisomers have been determined. Total HBCDs ranged from 0.09 to 26.8 ng g⁻¹, with higher concentrations in fish oil for feed (average value of 9.69 ng g⁻¹) than those for food (1.14 ng g⁻¹). Concentrations of α-HBCD (average value of 4.12 ng g⁻¹ in feed samples and 0.48 ng g⁻¹ in food samples) and γ-HBCD (5.05 and 0.43 ng g⁻¹ respectively) were higher than that of β-HBCD (0.52 and 0.19 ng g⁻¹ respectively) in most of the samples. However, none of them was predominant in the samples. Concentrations of HBCDs were compared to concentrations of other pollutants and correlation between dioxin and dioxin-like PCBs levels and HBCDs levels were observed. Intake of HBCDs was calculated for fish oil with human consumption purposes and it ranged from 0.08 to 5.38 ng HBCDs d⁻¹, which could contribute significantly to HBCDs total intake. Enantiomeric fractions were also determined. No clear enrichment was observed for γ-HBCD, while (−)-α-HBCD enrichment was detected in some samples.     

Risk ranking of multiple-POPs in detritivorous fish from the Río de la Plata

To evaluate the bioaccumulation and the risk associated to consumption of lipid-rich detritivorous fish, a comprehensive set of organic pollutants (n = 213) including polychlorinated biphenyls (PCBs), dioxin like PCBs (dlPCBs), chlorinated pesticides (CHLPs), chlorobenzenes (CBzs), polybrominated diphenyl ethers (PBDEs), polychlorinated dibenzo dioxins and furans (PCDD/F), resolved (ALI) and unresolved aliphatic hydrocarbons (UCM) and linear alkyl benzenes (LABs) were analyzed in Sábalo fish (Prochilodus lineatus) collected in the polluted Metropolitan Buenos Aires coast and in migrating specimens. Fatty fish muscles (lipids: 74 ± 9.3% dry weight) contained homogeneous (24-51% variability) and very high-concentrations of organic pollutants ranging from 60 to 1300 μg g⁻¹ fresh weight (fw) ALI + UCM; 10-40 μg g⁻¹ fw LABs and PCBs; 0.1-1 μg g⁻¹ fw dlPCBs, DDTs, chlordanes, CBzs and PBDEs; 0.01-0.1 μg g⁻¹ fw mirex, endosulfans, aldrin, dieldrin, endrin and 0.07-0.2 ng g⁻¹ PCDD/F. Total toxicity equivalents (TEQs) ranged from 60 to 395 pg g⁻¹ fw (34 ± 17 and 213 ± 124 pg g⁻¹ TEQs for PCDD/F and dlPCBs respectively). These are among the highest concentrations reported for fish and point out the remarkable ability of Sábalo to feed on anthropogenic organic-enriched particles and tolerate a high pollutant load. Contaminant signatures show partial alteration with still abundant lower molecular weight components indicating that fish feeds directly in the outfalls. Consumption limits based on reference doses ranged from 0.1 (PCBs) to >12 000 g d⁻¹ (endosulfan) allowing a comprehensive risk-based ranking of contaminants in this long-range migrating, detritivorous fish.     

Bioaccumulation of the pharmaceutical 17α-ethinylestradiol in shorthead redhorse suckers (Moxostoma macrolepidotum) from the St. Clair River, Canada

17α-ethynylestradiol (EE2), a synthetic estrogen prescribed as a contraceptive, was measured in Shorthead Redhorse Suckers (ShRHSs) (Moxostoma macrolepidotum) collected near a wastewater treatment plant (WWTP) in the St. Clair River (Ontario, Canada). We detected EE2 in 50% of the fish samples caught near the WWTP (Stag Island), which averaged 1.6 ± 0.6 ng/g (wet weight) in males and 1.43 ± 0.96 ng/g in females. No EE2 was detected in the samples from the reference site (Port Lambton) which was 26 km further downstream of the Stag Island site. Only males from Stag Island had VTG induction, suggesting the Corunna WWTP effluent as a likely source of environmental estrogen. EE2 concentrations were correlated with total body lipid content (R² = 0.512, p < 0.01, n = 10). Lipid normalized EE2 concentrations were correlated with δ¹⁵N (R² = 0.436, p < 0.05, n = 10), suggesting higher EE2 exposures in carnivores. Our data support the hypothesis of EE2 bioaccumulation in wild fish.     

Partitioning behaviour of perfluorinated alkyl contaminants between water, sediment and fish in the Orge River (nearby Paris, France)

This paper reports on the partitioning behaviour of 15 perfluorinated compounds (PFCs), including C₄-C₁₀ sulfonates and C₅-C₁₄ carboxylic acids, between water, sediment and fish (European chub, Leuciscus cephalus) in the Orge River (nearby Paris). Total PFC levels were 73.0 ± 3.0 ng L⁻¹ in water and 8.4 ± 0.5 ng g⁻¹ in sediment. They were in the range 43.1-4997.2 ng g⁻¹ in fish, in which PFC tissue distribution followed the order plasma > liver > gills > gonads > muscle. Sediment-water distribution coefficients (log K_d) and bioaccumulation factors (log BAF) were in the range 0.8-4.3 and 0.9-6.7, respectively. Both distribution coefficients positively correlated with perfluoroalkyl chain length. Field-based biota-sediment accumulation factors (BSAFs) are also reported, for the first time for PFCs other than perfluorooctane sulfonate. log BSAF ranged between −1.3 and 1.5 and was negatively correlated with the perfluoroalkyl chain length in the case of carboxylic acids.     

The impact of production type and region on polychlorinated biphenyl (PCB), polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/F) concentrations in Canadian chicken egg yolks

Chicken eggs from five different production types (conventional, omega-3 enriched, free range, organic and free run) were collected, when available, from three regions (west, central and east) of Canada to determine persistent organic pollutant (POP) concentrations. Total polychlorinated biphenyl (PCB) concentrations (∑37 congeners) in yolks from the eggs ranged from 0.162 ng g⁻¹ lipid to 24.8 ng g⁻¹ lipid (median 1.25 ng g⁻¹ lipid) while the concentration of the sum of the 6 indicator PCBs ranged from 0.100 ng g⁻¹ lipid to 9.33 ng g⁻¹ lipid (median 0.495 ng g⁻¹ lipid). Total polychlorinated dibenzo-p-dioxin/dibenzofuran (PCDD/F) concentrations ranged from 2.37 pg g⁻¹ lipid to 382 pg g⁻¹ lipid (median 9.53 pg g⁻¹ lipid). The 2005 WHO toxic equivalency (TEQ) ranged from 0.089 pg TEQ_{PCDD/F+dioxin-like[DL]-PCB} g⁻¹ lipid to 12.8 pg TEQ_{PCDD/F+DL-PCB} g⁻¹ lipid (median 0.342 pg TEQ_{PCDD/F+DL-PCB} g⁻¹ lipid). PCB and PCDD/F concentrations were significantly different (p < 0.001) in egg yolks from different regions of collection. In contrast to observations in Europe, PCB and PCDD/F concentrations in Canadian egg yolks were not impacted solely by the production type (e.g., conventional, free range, organic, etc.) used to maintain the laying chickens. Additionally, only one Canadian free range yolk from western Canada (12.8 pg TEQ_{PCDD/F+DL-PCB} g⁻¹ lipid) exceeded the European toxic equivalent concentration limits for eggs (5 pg TEQ_{PCDD/F+DL-PCB} g⁻¹ lipid). This differs from observations in Europe where free range/home produced eggs frequently have higher POP concentrations than eggs from other production types. Median PCB dietary intake estimates based on consumption of eggs were less than 10 ng d⁻¹ while median PCDD/F intakes were less than 45 pg d⁻¹.     

Environmental release of dioxins from reservoir sources during beach nourishment programs

In late 1990s, USEPA/FDA made an important connection regarding the presence of elevated levels of dioxins (e.g., 1500 ng kg⁻¹ TEQ) in ball clays mined in Mississippi (USA) from a geological deposit dated to ∼40 million years (Mississippi Embayment) that stretches over several states (northern part of Mississippi to Kentucky) and levels of dioxins in selected animal food sources. Following a recent beach nourishment program along the mid-Atlantic coast of the US, a number of dark gray, blue tinted nuggets of varying sizes were found on beach strands and near the shoreline. Using the presence of these balls of clay (shape, color, and knowledge regarding their use in pottery) on the beach, together with our direct experience analyzing ball clays for dioxins, we made a possible association between these clays and elevated dioxins. Concerns regarding the potential of nourishment programs to cause severe damage to our beaches drove us to test the dioxin content of nourishment exposed clays. A number of the nuggets, along with freshly dredged and deposited sand (collected the morning after nourishment) with the same coloration, and others (sun-bleached), collected approximately 2 weeks after the completion of the nourishment efforts, were analyzed for the presence of PCDD/Fs, PCBs, and selected semi-volatile chlorinated organics. The clay PCDD/F WHO2005-TEQs (dry weight; ND = DL; EMPC = EMPC) ranged from 0.41 to 5.78 ng kg⁻¹ with an average of 2.64 ng kg⁻¹, whereas the sand sample’s TEQs ranged from 0.18 to 0.31 ng kg⁻¹ PCDD/F WHO-2005, with an average of 0.22 ng kg⁻¹. The average total tetra- through octachlorinated dibenzo-p-dioxin concentration was 2700 ng kg⁻¹ (with a maximum of 5800 ng kg⁻¹) for the clays and 8.5 ng kg⁻¹ (with a maximum of 16.8 ng kg⁻¹) for the sand samples. The congener 2,3,7,8-TCDD (TEF = 1) was detected in half of the clay samples (0.11-0.77 ng kg⁻¹). All of the clay and sand samples displayed an unambiguous and dominating 1,4,6,9-chlorination pattern across homolog groups. No other chlorinated aromatics were detected above background levels. The observations, along with the absence or an extremely low level of polychlorinated dibenzofurans, together with the mineralogical analysis, supports the conclusion that off-shore dredging activities are reaching reservoir sources containing dioxin-tainted, smectic/kaolinite clay minerals. Subsequent beach erosion provides additional environmental releases over time, as buried balls of clay from previous nourishment efforts become exposed.     

Polybrominated diphenyl ethers (PBDEs) and mercury in fish from lakes of the Tibetan Plateau

High mountains may act as cold traps for globally transported persistent organic pollutants (POPs) and mercury (Hg). In the present study, 60 fish samples were collected from eight alpine lakes across the Tibetan Plateau. Concentrations of polybrominated diphenyl ethers (PBDEs), total mercury (HgT) and methyl mercury (MeHg) were quantified in the fish muscle tissues to improve the understanding of pollution status and factors regulating the transport and fate of these contaminants on the Plateau. The results showed that lake-averaged ∑₁₄PBDEs concentration was between 0.09 ng g⁻¹ dw and 4.32 ng g⁻¹ dw, which was lower than those reported for European mountains. The total mercury concentration in individual fish ranged from 243 to 2384 ng g⁻¹ dw, and that of MeHg from 131 to 1610 ng g⁻¹ dw, which is much higher than those reported in other mountain fish. The spatial variation of PBDEs and mercury in the Plateau is largely controlled by the specific meteorological patterns.     

Organochlorine contaminants in the hair of Iranian pregnant women

In the present study, the hair of pregnant women was sampled between November 2007 and January 2008 in Ahvaz and Noushahr cities and the countryside of Noushahr, Iran. They were analyzed for organochlorine pesticides (OCPs), such as dichlorodiphenyltrichloroethane (DDT) and its metabolites, hexachlorobenzene (HCB), α-, β-, and γ-hexachlorocyclohexane (HCH) isomers and seven polychlorinated (PCBs) congeners (IUPAC Nos. 28, 52, 101, 118, 138, 153 and 180). Significant differences between the concentrations of investigated pollutants were found between the locations (p < 0.05). For HCHs, the γ-HCH isomer was measured at higher mean concentrations (6 ng g⁻¹ hair) compared to the β-HCH isomer (0.03 ng g⁻¹), which generally is the most prevalent HCH in biological matrices. Very high mean concentrations of p,p′-DDT in countryside of Noushahr (24 ng g⁻¹) combined with lower values (0.6) of ratio p,p′-DDE/p,p′-DDT in the hair samples suggest recent exposure to “fresh” DDT in this region. Significant differences in OCPs and PCBs were found between primiparous and multiparous mothers (p < 0.05). There was no correlation between levels of OCPs and PCBs in the hair of Iranian pregnant women and their age. There was a significant difference (p < 0.05) in the organochlorine levels, including HCHs, between mothers who have eaten fish once a week and those who consumed fish more than once per week in Noushahr.