A numerical study on the seasonal variability of polychlorinated biphenyls from the atmosphere in the East China Sea

A three-dimensional/high-resolution transport model for persistent organic pollutants (POPs) has been developed for the East China Sea (ECS). The POPs model has four compartments (gaseous, dissolved, phytoplankton-bound, and detritus-bound phases) and includes processes for diffusive air-water exchange, phytoplankton uptake/depuration to POPs, decomposition of dissolved phase, vertical sinking of phytoplankton, detritus production by phytoplankton mortality, and vertical sinking and decomposition of detritus. The POPs model is coupled with an ocean circulation model that can reproduce the seasonal variation in physical variables to represent the advection and diffusion of POPs. We applied the POPs model to the polychlorinated biphenyl congener 153 (PCB 153) from the atmosphere and examined the behavior of PCB 153 in the ocean. The model showed a remarkable seasonal variability of PCB 153. Concentrations in the dissolved and particulate phases are high in winter (January-March) and low in summer (July-September). In coastal regions, where chlorophyll a concentration is high, horizontal and vertical distributions in the dissolved and particulate PCB 153 concentrations are strongly affected by phytoplankton uptake. The sensitivity experiments on the dynamics of PCB 153 suggested that a change of Henry’s law constant associated with water temperature is the major factor controlling the seasonal variability of PCB 153. The model-based yearly mass balance of PCB 153 in the ECS indicated that most of the atmospheric input (35.5 kg year⁻¹) is removed by the horizontal advection outside the ECS (19.0 kg year⁻¹) and accumulates to the sea bottom by vertical sinking (15.7 kg year⁻¹). For comparison with PCB 153, we also conducted simulations for PCB 52, 101, and 180. The seasonal variations are similar to that of PCB 153. The mass balance of PCB 52 that has short half-life time and less hydrophobic property shows the different results compared with PCB 101, 153, and 180.     

PBDE flame retardants and PCBs in migrating Steller sea lions (Eumetopias jubatus) in the Strait of Georgia, British Columbia, Canada

Polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) were measured in blubber biopsy samples from 22 live-captured Steller sea lions (Eumetopias jubatus) that had just entered the Strait of Georgia, British Columbia, Canada, for their overwintering feeding season. ∑PBDE ranged from 50 μg kg⁻¹ (lipid weight) in adult females to 3780 μg kg⁻¹ in subadult individuals. ∑PCBs ranged from 272 μg kg⁻¹ in adult females to 14 280 μg kg⁻¹ in subadult individuals. While most PBDE and PCB congeners were transferred through milk to pups, PCBs with log K_OW > 7.0 (PCBs 206, 207, 208 and 209) appeared constrained, resulting in a lighter mixture in pups compared to adult females. The ratio of individual PCB congeners by metabolic group (Groups I, II, III, IV and V) to PCB-153 regressed against length of males suggested poor biotransformation of these compounds (slopes did not differ from zero, p > 0.05). PBDE congeners 49, 99, 153 and 183 appeared bioaccumulative (slopes of ratio BDE/PCB 153 versus length were higher than zero, p < 0.05), but the dominance of the single congener, BDE-47 (64% of total PBDEs), likely due in part to debromination pathways, reduced our ability to explore congener-specific dynamics of PBDEs in these pinnipeds. With 80% of our Steller sea lions exceeding a recent toxicity reference value for PCBs, the fasting-associated mobilization of these contaminants raises concerns about a heightened vulnerability to adverse effects during annual migrations.     

A rapid method for screening of the Stockholm Convention POPs in small amounts of human plasma using SPE and HRGC/HRMS

A rapid analytical screening method allowing simultaneous analysis of 23 persistent organic pollutants (POPs) in human plasma was developed. Sample preparation based on solid-phase extraction (SPE) with additional clean-up using small multilayer silica gel columns. SPE was performed using a custom made polystyrene-divinylbenzene sorbent for the extraction of chlorinated and brominated POPs. Special efforts to reduce sample volume and improve speed and efficiency of the analytical procedure were made. Determination of 16 polychlorinated biphenyls (PCBs), 5 organochlorine (OC) pesticides, octachlorinated dibenzo-p-dioxin (OCDD) and polybrominated diphenyl ether (BDE #47) in 0.5 mL human plasma was performed by using high resolution gas chromatography coupled to high resolution mass spectrometry (HRGC/HRMS). Recovery of POPs ranged between 46% and 110%, and reproducibility was below 25% relative standard deviation (RSD) for all target compounds, except for trans-nonachlor and OCDD, which were present only at low levels. Limits of detection (LOD) were for the PCBs between 0.8 and 117.7 pg mL⁻¹ plasma and for the OC pesticides between 5.9 and 89.1 pg mL⁻¹ plasma. The LOD for OCDD and BDE #47 were 1.4 pg mL⁻¹ plasma, and 9.2 pg mL⁻¹ plasma, respectively. The presented method was successfully applied to 1016 human plasma samples from an epidemiological study on cardiovascular disease.     

Polybrominated diphenyl ethers occurrence in major inflowing rivers of Lake Chaohu (China): Characteristics,potential sources and inputs to lake

Eight commonly occurring polybrominated diphenyl ethers (PBDEs), including BDE 28, 47, 99, 100, 153, 154, 183, 207, and 209, were investigated in water samples from seven major inflowing rivers of Lake Chaohu to determine the distribution characteristics, potential sources and inputs to the lake. The sum of 8 BDE congeners (Σ₈PBDEs) had a concentration varied from 0.31 to 84 ng L⁻¹, with those of BDE 209, BDE 47, BDE 99, and BDE 153 being 0.31–83, <0.012–0.36, <0.012–1.3, and <0.012–0.77 ng L⁻¹, respectively. These levels were in the high range of the global PBDEs concentrations in the water environments. The highest concentrations of Σ₈PBDEs were detected in the western rivers, of which the main pollution sources were strongly related to human activities in urban centers, such as automobile-derived wastes. A sewage treatment plant was likely an important source of the lower brominated BDEs input to one western river. The correlation analyses (all p < 0.05) between PBDEs and DOC, TN, TP, and EC, suggested that the distributions and sources of PBDEs in rivers might also be related with the soil erosion by heave floods. Σ₈PBDEs input to Lake Chaohu from the rivers outlets was estimated at 344 kg yr⁻¹ during the flood season. BDE 209 was the dominant contributor with an input of 340 kg yr⁻¹, followed by BDE 99 (1.3 kg yr⁻¹), BDE 47 (0.83 kg yr⁻¹) and BDE 153 (0.60 kg yr⁻¹).     

Persistent organic pollutants (POPs) in human milk: A biomonitoring study in rural areas of Flanders (Belgium)

To collect information on the concentrations of persistent organic pollutants (POPs) in the rural areas in Flanders (Belgium), 84 breastfeeding mothers were recruited in rural communities in East and West Flanders and Flemish Brabant in 2009-2010. Polychlorinated biphenyl (PCB) congeners, organochlorine pesticides, brominated flame retardants, perfluorinated compounds, polychlorinated dibenzodioxines and dibenzofurans, and dioxin-like PCBs were measured in individual milk samples and in a pooled milk sample, while some additional pollutants were only measured in the pooled sample. For most pollutants, the concentrations in this study were lower or comparable to the concentrations measured in the pooled Belgian sample of the WHO human milk study of 2006, except for the pesticides dichlorodiphenyltrichloroethane DDT (+25% for ΣDDT and metabolites) and trans-nonachlor (+94%), and for the brominated flame retardant hexachlorocyclododecane HBCD (+153%). Perfluorinated compounds were for the first time determined in human milk samples from Belgium and the concentrations were comparable to those from other European countries. Also, interesting associations were found between the concentrations of POPs measured in human milk and personal characteristics as well as dietary habits of the study population. PFOS en PFOA concentrations were significantly higher in milk of primiparous participants compared to mothers who gave birth to their second child. Lower brominated PBDE congeners increased with increasing BMI of the mothers (p = 0.01 for BDE 47, p = 0.02 for BDE 99 and p = 0.02 for BDE 100). Participants consuming milk or dairy products daily had significant higher concentrations of ΣDDTs (p = 0.03) and oxychlordane (p = 0.047) in their human milk samples.     

Levels and distribution of polybrominated diphenyl ethers (PBDEs) in marine fishes from Chinese coastal waters

Concentrations of polybrominated diphenyl ethers (PBDEs) in yellow croakers (Pseudosciaena crocea) and silver pomfrets (Pampus argenteus) collected from nine coastal cities along the eastern China coastline were investigated. PBDE congeners with mono- to hexa-brominated substitutions were detected in the samples, indicating their ubiquitous distribution in the marine environment of China. The total PBDE concentration averaged 3.04 ng g⁻¹ lipid wt, a level that was relatively lower than in other regions of the world, especially North America where Penta-BDE was extensively used. Geographically, the highest concentration of PBDEs was found in Xiamen, and the PBDE levels in yellow croakers were significantly higher than those in pomfrets in most of the selected cities, a pattern which may be related to the different feeding habits of the two species. The congener profiles of PBDEs were found to be different from the commonly detected pattern in fishes from other regions of the world (i.e., BDE47 > BDE99, BDE100 > BDE153, BDE154). BDE47 and BDE154 were the predominant congeners in both species, accounting for more than 60% of the total PBDE concentrations. The reasons for the relatively high proportion of BDE154 may be due to the debromination of higher brominated congeners such as BDE183 and BDE209 by these two species.     

Serum concentrations of persistent organic pollutants (POPs) in the inhabitants of a Sicilian city

Background

Polychlorinated biphenyls (PCBs) and organochlorine pesticides are common environmental contaminants that have been associated with human health problems.

Objectives

To assess serum concentrations of several organochlorine contaminants in general population living in a city with an ancient agricultural tradition and to identify possible exposure sources in Sicily.

Methods

A cross-sectional study was conducted on 101 individuals. Each participant answered a face-to-face questionnaire submitted by well-trained personnel and provided a serum sample which was analyzed for the concentrations of PCBs, HCB, HCHs and DDTs by using gas-chromatography coupled with mass spectrometry.

Results

HCB, p,p′-DDE, PCB 138, PCB 153 and PCB 180 were detected in more than 80% of the study participants. The ng g⁻¹ lipid median concentrations were: 18.6 for HCB; 175.1 for p,p′-DDE; 22. for PCB 138; 32.5 for PCB 153 and 23.0 for PCB 180. PCB 153 and PCB 138, PCB 138 and PCB 180, PCB 153 and PCB 180, and p,p′-DDE and HCB showed a high correlation each other (p < 0.05). HCB and p,p′-DDE concentrations were significantly higher in subjects >49 years old (adj-p = 0.03 in 50-69 years old and adj-p < 0.001 in >69 years old, respectively) whereas PCB 138, PCB 153 and PCB 180 concentrations were higher in males (adj-p = 0.03), in subjects >69 years old (adj-p = 0.04) and in current smokers (adj-p = 0.04).

Conclusions

The present study shows that serum concentrations of organochlorine compounds detected in subjects living in a small Sicilian city with ancient agricultural tradition are similar to those found in subjects living in urban areas of other countries. However, further investigations are needed to compare data from rural/urban areas in the same country, assessing correlations between serum concentrations of several chemical compounds and potential health effects in general population.     

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).     

Occurrence, compositional patterns, and possible sources of polybrominated diphenyl ethers in agricultural soil of Shanghai, China

The present study analyzed surface soil collected from agricultural region of Shanghai to determine the occurrence, compositional patterns and possible sources of polybrominated diphenyl ethers (PBDEs). The results showed that 32 PBDEs were detected among 44 target PBDEs. Total PBDE concentrations ranged from 129 to 1245 ng kg⁻¹ with a mean of 429 ng kg⁻¹. BDE209 was the predominant congener in a range of 33.2-796 ng kg⁻¹ with a mean of 254 ng kg⁻¹. Meanwhile, BDE47, BDE49, BDE153, BDE190, and BDE99 have the most abundant with high concentrations and detectable frequencies. PBDE congeners and homologues analysis and principal component analysis (PCA) also revealed that the major source of PBDE in the soil samples was associated with the prevalent use of technical decabromodiphenyl ether (Deca-BDE) and pentabromodiphenyl ether (Penta-BDE). The correlation analysis proved that there was a significant correlation between total organic carbon (TOC) and lower brominated PBDEs, indicating the significant diffuse nature of the sources of these congeners.     

Polychlorinated biphenyls (PCBs) and Polybrominated Diphenyl Ethers (PBDEs) in surface sediments from Monastir Bay (Tunisia,Central Mediterranean): Occurrence,distribution and seasonal variations

An assessment of PCB and PBDE contamination of surface sediments in Monastir Bay was carried out in two contrasted seasons of the year. Samples were collected from 5 sites and analyzed for the ∑₇ marker PCBs (i.e. PCBs 28, 52, 101, 118, 138, 153 and 180) and ∑₄ PBDE congeners (PBDEs 47, 99, 119 and 153) by GC/ECD. Concentrations of both PCBs and PBDEs showed seasonal variations. PCB concentrations were in the range of 3.1–9.3 ng g⁻¹ and 1.1–8.1 ng g⁻¹ in wet and dry season respectively, and sediments were considered moderately contaminated with PCBs. All PCBs analyzed were detected in surface sediments. PCB 153 and 52 congeners showed the highest relative abundance in both winter and summer. PBDE concentrations ranged from not detect to 0.1 ng g⁻¹, with only BDE-47 congener detected in sediments and only in winter. Analysis of spatial and seasonal variations indicated that PCB distribution is governed by hydrodynamics and temporal variability of inputs. While the PCB contamination appeared to be mainly land-based, PBDEs are suspected to originate from atmospheric deposition.     

PCDD/F, PCB, PBDE, HBCD and chlorinated pesticides in a Swedish market basket from 2005--levels and dietary intake estimations

Based on consumption data statistics, food items from four regions in Sweden were sampled in a so-called market basket study. Food items from five food groups, i.e. fish, meat, dairy products, eggs and fat/oils, were analyzed for persistent organic pollutants (POPs) followed by per capita intake calculations. The highest levels of PCDD/F, PCB, PBDE, HBCD and chlorinated pesticides were found in the fish/fish products. The estimated market basket per capita intake of PCDD/F and dl-PCB was 0.7 pg WHO-TEQ kg bw⁻¹ d⁻¹ (TEFs from 1998). The intake of ∑PCB was estimated to 4.9 ng kg bw⁻¹ d⁻¹ and fish was found to be the major contributor with 64%. The intake of ∑PBDE was found to be 0.7 ng kg bw⁻¹ d⁻¹. Fish (38%) and dairy products (31%) were the largest contributors to the total PBDE intake. The intake of HBCD was estimated to 0.14 ng kg bw⁻¹ d⁻¹. HBCD mainly came from fish (65%), but also dairy products (24%) and meat (10%) contributed. Also regarding the chlorinated pesticides, fish was found to be the major contributor, with 51% of the ∑DDT coming from fish. The intake of ∑DDT, ∑HCH and HCB was 4.0, 1.0 and 1.1 ng kg bw⁻¹ d⁻¹, respectively. Most of the ∑HCH and HCB originate from dairy products (43% and 55%, respectively). This study shows that the levels, and intake, of different POPs from food of animal origin in the market basket of 2005 seem to have decreased since the market basket study in 1999.     

Polychlorinated biphenyls in vacuum dust and blood of residents in 20 Wisconsin households

Human exposure to PCBs is nearly universal in North America. While most exposure can be linked to consumption of contaminated fish, detection of PCBs in non-fish eating populations suggests that other routes of exposure including inhalation of PCB-laden particles or volatile congeners, ingestion of contaminated soil or dust, or dermal absorption following direct contact are also important. In an effort to assess the role of the residential environment as a source of exposure, vacuum dust was collected from the homes of 26 Wisconsin residents whose serum PCB levels had been measured approximately 2 years earlier. More than 60 congeners were detected in dust with all of the samples containing congeners 101, 110, 138 and 153. Total PCB levels ranged from 8.8 to 1186 ng g⁻¹ with levels being highest in vacuum dust from homes built between 1959 and 1970. Total PCB levels ranged from 0.05 to 8.34 μg L⁻¹ in serum collected from the adults living in these households, with congeners 138, 153 and 180 predominating. Hexa- and hepta-chlorinated biphenyls comprised 73% of the total residues detected in serum. However, most of the residues found in dust were lower chlorinated congeners with tetra- and penta-chlorinated biphenyls being dominant. Following log transformation, a positive association was found between serum and house dust PCB levels. This association was stronger among infrequent consumers of Great Lake fish, but of borderline statistical significance. This exploratory study suggests that house dust may be a significant source of exposure to PCBs and supports the need for further investigations.     

Relative bioavailability to laying hens of indicator polychlorobiphenyls present in soil

Transfer of indicator polychlorobiphenyls (PCBs) from soil into hen eggs may occur in hens reared outdoor, which ingest significant amounts of soil. This transfer depends on the bioavailability of the ingested compounds. The impact of soil on the bioavailability of indicator PCBs was assessed by means by a relative bioavailability (RBA) trial, in which their deposition in egg yolk and in abdominal fat, in response to their ingestion through contaminated-soil and through spiked-oil were compared. A sandy soil (709 μg indicator PCBs kg⁻¹ dry matter) was collected in the vicinity of a former fire involving treated wood. Twenty-eight laying hens were individually housed and fed one of the seven experimental diets during 14 d. The seven experimental diets were an uncontaminated control diet, three diets in which contaminated soil was introduced at levels of 3%, 6% and 9% and three diets in which spiked oil was introduced to achieve similar levels and profile of contaminants. Yolk, abdominal fat and liver were collected at the end of exposure. Indicator PCBs were extracted by ASE (Accelerated Solvent Extraction) and analyzed by GC-HMRS. Within each ingested matrix, the concentration of indicator PCBs in yolk and in abdominal fat linearly increased with the amount of indicator PCB ingested (P < 0.001). Except for PCB 28, the slopes of the responses to soil and to oil could not be differentiated (P > 0.1). RBA estimates did not differ from 1 for all indicator PCBs except for PCB 28, for which it was 0.58-0.59. Measurements performed on liver confirm these conclusions.     

Persistent organic pollutants (PCB, DDT, HCH, HCB & BDE) in eels (Anguilla anguilla) in Scotland: Current levels and temporal trends

Eels are an ideal biomonitor for persistent organic pollutants (POPs) because of their high lipid content, longevity and tendency to remain within a defined range during their freshwater life phase. This study investigated concentrations of POPs in eels (Anguilla anguilla) from 30 sites across Scotland, including polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (BDEs), DDT (and metabolites), hexachlorocyclohexanes (α, β, γ-HCH), hexachlorobenzene (HCB), hexachlorobutadiene (HCBD) and pentachlorobenzene. Despite its EU-wide ban ∼30 years ago, DDT and its derivatives were detected in almost all samples. PCB 153 and 138 were the most widely detected PCB congeners, while BDE 47 was the dominant BDE. Pentachlorobenzene was not detected, while HCBD was detected once only. α-HCH, β-HCH and HCB concentrations were very low (generally <3 μg/kg or below detection). When compared with 1986 and 1995 data, the results revealed considerable decreases in p,p′-DDE concentrations. More drastic reductions were evident for γ-HCH, reflecting the tightening restrictions on pesticide use imposed over the previous decades.     

Suitability of a magnetic particle immunoassay for the analysis of PBDEs in Hawaiian euryhaline fish and crabs in comparison with gas chromatography/electron capture detection-ion trap mass spectrometry

A gas chromatograph/electron capture detector-ion trap mass spectrometer (GC/ECD-ITMS) was used for the determination of polybrominated diphenyl ethers (PBDEs) in euryhaline fish and crabs. GC/ECD-ITMS results showed that average recoveries from the spiked fish samples are in a range of 58-123% with relative standard deviations (RSDs) of 5-19%. PBDE concentrations obtained from GC/ECD-ITMS ranged from 28 ng/g to 1845 ng/g lipid weight (lw) in all aquatic species collected from Hawaiian brackish waters. The general BDE congener concentration profile observed in this study is BDE-47 > BDE-100 > BDE-154 > BDE-99 > BDE-153 > BDE-28 > BDE-183. The ELISA results expressed as BDE-47 equivalents correlated well with those of GC/ECD-ITMS, with a correlation coefficient (R² = 0.68) and regression coefficient (slope = 0.82). Comparison of ELISA with GC/ECD-ITMS results demonstrated that ELISA provides a timely and cost-effective method to screen PBDEs in fish and crab samples.     

Polychlorinated biphenyls (PCBs) residues in milk from an agroindustrial zone of Tuxpan, Veracruz, Mexico

The coasts of the Gulf of Mexico are zones exposed to the exploration and exploitation of petroleum sources, and the products generated in agricultural zones may become contaminated by persistent organic pollutants (POPs). The objective of the present study was to evaluate the presence of polychlorinated biphenyl compounds (PCBs) in milk from dairy production units near sources of environmental pollutants. It was confirmed that the seven congeners of nondioxin-like PCBs (NDL-PCBs) are present in milk where compounds PCB101, PCB118, PCB153 and PCB180 appear in 100% of the samples analyzed, the rank of concentration for the sum of the seven congeners fluctuating between 2.6 and 26 ng g⁻¹ with a median of 6 ng g⁻¹. None of the samples surpassed the provisional value established by the EU of 40 ng g⁻¹ of milk fat for the sum of the seven congeners, indicator that was not affected by the season of the year (p < 0.05), whose median of 8.6 ng g⁻¹ and 6.3 ng g⁻¹ for rain and drought respectively. The concentrations of NDL-PCBs found in milk do not represent a problem for human health; however, they alert the existence of spontaneously generated, uncontrolled sources that may represent a potential danger for human and animal health.     

PCDDs, PCDFs, dioxin-like PCBs and indicator PCBs in soil from five selected areas in Slovakia

There is a lack of information regarding persistent organic pollutants (POPs) in soil from Slovakia. This paper reports the concentrations of 17 polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), 12 dioxin-like polychlorinated biphenyls (dl-PCBs) and 6 indicator PCBs associated with 32 soil samples collected in 2007 from areas in the vicinity up to several kilometres from four selected industrial PCDD/F sources in Slovakia and one background area.The results show that the total WHO₁₉₉₈-PCDD/F/dl-PCB-TEQ concentrations varied from 0.34 to 18.05 pg g⁻¹ dry weight (dw) and the average total TEQ concentrations in samples collected at the Šala, Košice, Krompachy and Dubová areas were 3.18, 2.64, 7.80, and 3.19 pg g⁻¹ dw respectively. The average of the total WHO₁₉₉₈-TEQ values in three soil samples representing the background Starina area was 0.66 pg g⁻¹ dw. The predominant contaminants among 2,3,7,8-substituted PCDD/Fs, dl-PCB, and indicator PCBs was OCDD, PCB 118, and PCB 153 respectively. The major contributors to the TEQ were 2,3,4,7,8-PeCDF, PCB 126, 1,2,3,7,8-PeCDD, PCB 156 and 1,2,3,4,7,8-HxCDF + 1,2,3,4,7,9-HxCDF in descending order.     

NDL-PCBs in muscle of the European catfish (Silurus glanis): An alert from Italian rivers

The non-dioxin-like polychlorinated biphenyls (NDL-PCBs) highly contribute to the PCB dietary intake of total PCBs. Most of the NDL-PCBs are assumed through ingestion of contaminated fish and fishery products. Therefore, it is important to quantify their presence in aquatic organisms to evaluate human risks associated with fish consumption. The European catfish is a top food-chain predator and is considered a reliable bio-monitoring tool reflecting the state of the environmental organic pollution. From 2006 to 2009, 54 European catfish were captured in four sites covering the area of the Po River (North Italy), and their muscles were analysed to determine the levels of 18 PCBs congeners. All samples presented detectable levels of 18 congeners and, on average, results showed an important presence of NDL-PCBs. The sum of the six congeners (28, 52, 101, 138, 153, 180 IUPAC) was used as indicator of the total PCBs concentration. The 33% of the samples analysed exceeded the maximum levels of 125 ng g⁻¹ set by European regulations in fish. The values measured ranged from 19.7 to 1015.4 ng g⁻¹ (mean 135.6 ± 149.8 ng g⁻¹).     

Nationwide monitoring of atmospheric PCDD/Fs and dioxin-like PCBs in South Korea

Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) were measured in ambient air samples collected from different parts of South Korea in 2008, and the measured levels were used for assessing the spatial and temporal distribution of atmospheric PCDDFs and DL-PCBs in South Korea. The average concentrations of atmospheric PCDD/Fs and DL-PCBs among the 37 sites were 28 fg I-TEQ m⁻³ (ND ∼ 617) and 1 fg WHO-TEQ m⁻³ (ND ∼ 0.016). Elevated atmospheric levels of PCDD/Fs and DL-PCBs observed at residential/industrial sites and in the north-west of Korea, indicated a potential contribution and impacts of anthropogenic sources of PCDD/Fs and DL-PCBs. These levels were similar or lower than those previously reported in other ambient air surveys. Average concentrations of PCDD/Fs showed small seasonal variations (ANOVA analysis, p = 0.144). The highest concentrations of PCDD/Fs were observed during winter, followed by spring, autumn and summer. Atmospheric PCDD/Fs and DL-PCBs in South Korea rapidly decreased during the last 10 years (1998-2008), demonstrating the efficiency of stricter regulations and the application of best available technologies/best environmental practices at emission sources. Comparison of the congener profiles and principal component analysis showed that current atmospheric PCDD/Fs are mostly influenced by industrial sources and PCBs from old commercial PCB uses. Nationwide POPs monitoring will continue and allows an effective evaluation of the implementation of the Stockholm Convention on POPs.     

Occurrence of co-planar polybrominated/chlorinated biphenyls (PXBs), polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in breast milk of women from Spain

In this study, for the first time, levels and accumulation profiles of eight currently available polybrominated/chlorinated biphenyl congeners (PXBs; XB-77, -105, -118, -126A, -126B, -126C, -156 and -169, named according to IUPAC nomenclature) in human breast milk collected form Spanish women in 2005 were reported. Concentrations and congener specific profiles of polychlorinated biphenyls (PCBs), including co-planar PCBs, (co-PCBs) and polybrominated diphenyl ethers (PBDEs) were also reported.A concentration of 0.45 pg g⁻¹ lipid weight was found for total PXBs, and arithmetic mean concentrations of 125, 25 and 5.5 ng g⁻¹ lipid weight were determined for total PCBs, co-PCBs and total PBDEs respectively. Detectable levels of all congeners investigated, except CB-123 and XB-169 were found. Levels of PCBs were similar to those found in Spanish samples collected after 2000, and lower than those obtained before 2000. CB-138, -153 and -180 were the predominant PCB congeners. PBDE levels, dominated by BDE-47, -99, -100 and -209, were lower than PCB levels. PXB concentrations were the lowest, with XB-156 being the most abundant. The concentration levels of PCBs and PBDEs found in this study were in the same range as those from other European countries. Levels of PXBs were much lower than published values determined in Japan which were the only data found in the literature.