Polychlorinated dibenzo-p-dioxins and dibenzofurans in sediment, soil, fish, shellfish and crab samples from Tokyo Bay area, Japan

Levels, congener profiles, and dietary intake assessment of polychlorinated dibenzo-p-dioxins/dibenzofurans and dioxin-like polychlorinated biphenyls in beef, freshwater fish, and pork marketed in Guangdong Province, China

Persistent organic pollutants such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (DL-PCBs) consisting of non-ortho and mono-ortho PCBs are suggested to be very hazardous and have adverse effects on human health. However, their levels and congener profiles in retail foods marketed in Guangdong Province of China have not been elucidated thus far. Thus, in this study, 226 individual samples of beef, freshwater fish, and pork marketed across four regions of Guangdong Province were randomly collected during 2013-2015 to determine their levels of PCDD/Fs and DL-PCBs. The results showed that the total toxic equivalency quantities (TEQs) of most samples were below the maximum limits except for the 26 samples collected from the vicinities of pollution areas. The median total TEQs of these three categories were 0.174, 0.488, and 0.113pgTEQ/g fw, respectively, which indicated that the contamination status of the studied foods was not serious. For congener profiles, significantly different patterns were observed in three food groups, but with the same major TEQ contributors being 2,3,4,7,8-PeCDF in beef, freshwater fish, and pork. Regional differences of congener profiles in each food group were also found in this study, which might be attributed to the regionally different distributions of PCDD/Fs and DL-PCBs in environment media. The dietary exposures of four population subgroups (girls, boys, male adults, and female adults) to PCDD/Fs and DL-PCBs via three food groups were estimated to assessed the potential risks. They were all lower than the provisional tolerable monthly intake (PTMI, 70pgTEQ/kgbw/month) established by Joint FAO/WHO Expert Committee on Food Additive. In these food categories, the exposure to PCDD/Fs and DL-PCBs via freshwater fish was the highest one, which accounted for about 20% of PTMI, indicating that it was the major route to expose dioxin compounds.

Occurrence of Natural Mixed Halogenated Dibenzo-p-Dioxins: Specific Distribution and Profiles in Mussels from Seto Inland Sea, Japan

In addition to unintentional formation of polychlorinated (PCDD/Fs), polybrominated (PBDD/Fs), and mixed halogenated (PXDD/Fs) dibenzo-p-dioxins/dibenzofurans during industrial activities, recent studies have shown that several PBDD and PXDD congeners can be produced by marine algal species from the coastal environment. However, multiple exposure status of anthropogenic and naturally derived dioxins in marine organisms remains unclear. The present study examined the occurrence, geographical distribution, and potential sources of PCDD/Fs, PBDD/Fs, and PXDD/Fs using mussels and brown algae collected in 2012 from Seto Inland Sea, Japan. The results showed the widespread occurrence of not only PCDD/Fs but also PBDDs and PXDDs in Seto Inland Sea. The geographical distribution pattern of PBDDs was similar to that of PXDDs, which were obviously different from that of PCDDs and PCDFs, and a significant positive correlation was observed between the levels of their predominant congeners, i.e., 1,3,7-/1,3,8-TrBDDs and DiBMoCDDs. Interestingly, potential precursors of 1,3,7-/1,3,8-TrBDDs and DiBMoCDDs, hydroxylated tetrabrominated diphenyl ethers (6-HO-BDE-47 and 2'-HO-BDE-68) and their mixed halogenated analogue (HO-TrBMoCDE), were also identified in the mussel and brown alga samples collected at the same site, by comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GC × GC-ToFMS) analyses. It is noteworthy that residue levels of 1,3,7-/1,3,8-TrBDDs and DiBMoCDDs in the mussel were 30 times higher than those in the brown alga, suggesting the bioaccumulation of these natural dioxins.

Changing sources of polychlorinated dibenzo-p-dioxins and furans in sediments and ecological risk for nekton in the lower Passaic River and Newark Bay, New Jersey, USA

Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were measured in sediments (surface and deeper sediments) and porewater of the lower Passaic River and Newark Bay (New Jersey, USA) to apportion their sources and conduct an ecological risk assessment. Positive matrix factorization was applied to identify sources of PCDD/Fs. Five source profiles were extracted from the positive matrix factorization model applied to the sediment samples including chloranil, combustion, polychlorinated biphenyl impurities, mixed urban sources, and the historical contamination from the former Diamond Alkali plant. The ecological risk assessment was estimated using several lines of evidence depending on site-specific data (blue crab and fish samples representing different feeding habits and positions in the trophic wood web of the river). Porewater concentrations gave the best estimates of lipid concentrations especially in the blue crab samples (with an average factor difference of 3.8). Calculated hazard quotients (HQs) for the fish samples and blue crab were >1 based on the no-effect concentration and tissue screening concentration approaches. At the same time, calculated porewater toxic units were >1. Sediment concentrations exceeded the published sediment quality guidelines for the protection of fish and benthic species, indicating the existence of significant risk to the aquatic life in the Passaic River. Accordingly, further actions and control measures are needed to reduce the emission of PCDD/Fs from ongoing sources.

Bioaccumulation of mercury and polychlorinated dibenzo-p-dioxins and dibenzofurans in salty water organisms

Mercury and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) accumulate in organisms through food webs and exert potentially toxic effects on aquatic organisms and humans. This study examined the levels of mercury and PCDD/Fs in organisms and sediment samples collected from a saltwater pond at the An-Shun site, a chloralkali factory that shut down in Tainan City, Taiwan. It was also a pentachlorophenol production plant. After the factories were shut down in the 1980s, mercury and PCDD/Fs contamination remained, posing severe health hazards. The correlation between PCDD/Fs congener accumulation patterns in distinct fish organs and the sediment was evaluated. Mercury and PCDD/Fs levels in all the fish samples exceeded food safety limits, and the concentrations of mercury and PCDD/Fs in each species were closely correlated (n = 12, Spearman's rank correlation [R] = 0.811, p < 0.01). The mercury concentrations were positively but non-significantly correlated with the weight (n = 11, R = 0.741, p < 0.01) and length (n = 11, R = 0.618, p < 0.05) of the species. The fish likely accumulated the contaminants through ingestion of other organisms or the sediment. However, after the pollutants entered a fish, they exhibited distinct accumulation patterns because of their differing chemical properties. Specifically, the mercury concentration was correlated with organism weight and length, whereas the PCDD/Fs concentration was associated with organ lipid content. The study results are valuable for assessing the health risks associated with ingesting mercury- and PCFF/F-contaminated seafood from the study site.

Temporal trends for inflow of perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) to Tokyo Bay, Japan, estimated by a receptor-oriented approach

We estimated inflow rates of perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) to Tokyo Bay, Japan, between February 2004 and February 2011 by a receptor-oriented approach based on quarterly samplings of the bay water. Temporal trends in these inflow rates are an important basis for evaluating changes in PFOS and PFOA emissions in the Tokyo Bay catchment basin. A mixing model estimated the average concentrations of these compounds in the freshwater inflow to the bay, which were then multiplied by estimated freshwater inflow rates to obtain the inflow rates of these compounds. The receptor-oriented approach enabled us to comprehensively cover inflow to the bay, including inflow via direct discharge to the bay. On a logarithmic basis, the rate of inflow for PFOS decreased gradually, particularly after 2006, whereas that for PFOA exhibited a marked stepwise decrease from 2006 to 2007. The rate of inflow for PFOS decreased from 730kg/y during 2004-2006 to 160kg/y in 2010, whereas that for PFOA decreased from 2000kg/y during 2004-2006 to 290kg/y in 2010. These reductions probably reflected reductions in the use and emission of these compounds and their precursors in the Tokyo Bay catchment basin. Our estimated per-person inflow rates (i.e., inflow rates divided by the estimated population in the basin) for PFOS were generally comparable to previously reported per-person waterborne emission rates in Japan and other countries, whereas those for PFOA were generally higher than previously reported per-person waterborne emission rates. A comparison with previous estimates of household emission rates of these compounds suggested that our inflow estimates included a considerable contribution from point industrial sources.

Characterization of polychlorinated biphenyls, pentachlorobenzene, hexachlorobenzene, polychlorinated dibenzo-p-dioxins, and dibenzofurans in surface sediments of Muroran Port, Japan

We determined the distribution of polychlorinated biphenyls (PCBs), pentachlorobenzene (PeCBz), hexachlorobenzene (HxCBz), and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in surface sediments at 21 sites inside and outside Muroran Port, Japan. The concentration ranges and geometric means of PCBs (Σ209PCB), PeCBz, HxCBz, and PCDD/Fs and toxicity equivalence quantity (total TEQ) of dioxins inside Muroran Port were 1,100-65,000 (mean, 17,000) pg/g dw, 37-220 (100) pg/g dw, 31-810 (84) pg/g dw, 69-410 (170) pg/g dw, and 0.51-6.2 (2.3) pg TEQ/g dw, respectively. Their corresponding inventories inside Muroran Port were estimated to be 76, 0.31, 0.32, 0.55, and 7.8 g TEQ, respectively. The amounts of these pollutants were higher inside the port than outside the port and especially large in the inner part of the port. Most PCBs were homologues and congeners of penta- to hepta-chlorinated compounds, and the PCBs around Muroran Port were derived from technical PCBs, especially KC500 and KC600. As for PCDD/Fs, the influence of pentachlorophenol was significant, although pollution due to chloronitrofen and combustion was detected. The congeners of PCDD/Fs predominantly contributed to total TEQ. The concentration distributions of PeCBz, HxCBz, and PCDD/Fs and total TEQ were highly correlated with one another. This indicates that they are derived from the same combustion process.

Guidelines for biomonitoring persistent organic pollutants (POPs), using lichens and aquatic mosses--a review

During the last decades, awareness regarding persistent organic pollutants (POPs), such dioxins and furans (PCDD/Fs) and polycyclic aromatic hydrocarbons (PAHs), has become a cutting-edge topic, due to their toxicity, bioaccumulation and persistency in the environment. Monitoring of PCDD/Fs and PAHs in air and water has proven to be insufficient to capture deposition and effects of these compounds in the biota. To overcome this limitation, environmental biomonitoring using lichens and aquatic mosses, have aroused as promising tools. The main aim of this work is to provide a review of: i) factors that influence the interception and accumulation of POPs by lichens; ii) how lichens and aquatic bryophytes can be used to track different pollution sources and; iii) how can these biomonitors contribute to environmental health studies. This review will allow designing a set of guidelines to be followed when using biomonitors to assess environmental POP pollution.

Levels, profiles and source identification of PCDD/Fs in farmland soils of Guiyu, China

The present study finished the first comprehensive survey of polychlorinated dibenzo-p-dioxin and dibenzofurans (PCDD/Fs) in farmland soils of Guiyu, China. Guiyu was a major electronic wastes (EWs) dismantling area, but primitive and crude EWs disposal manner had led to severe PCDD/Fs pollution there. Twenty-three farmland soil samples covering the entire Guiyu region were analyzed. Toxic equivalent quantities (I-TEQs) of soils in EWs disposal areas were 5.7-57pg TEQ g(-1), and the total concentrations of tetra- to octa-homologues were 2816-17738pgg(-1). The SL district was a heavily contaminated area, and the neighboring SMP town was influenced by Guiyu. EWs disposal might be the source of PCDD/Fs. The homologue profiles were of three types, representing different disposal manner of EWs. Tetrachlorodibenzo-p-dioxins (TCDDs) and octachlorodibenzo-p-dioxin (OCDD) could be used as indicators for source identification, open thermal disposal of EWs was inclined to lead to formation of TCDDs, OCDD was a product of non-thermal processes.

Sources and distribution of polychlorinated-dibenzo-p-dioxins and -dibenzofurans in soil and sediment from the Yellow Sea region of China and Korea

Polychlorinated-dibenzo-p-dioxins and -dibenzofurans (PCDD/Fs) were measured in soils and sediments from the Yellow Sea region. Korean soils and sediments mostly contained detectable PCDD/Fs and showed a widespread distribution among locations. Soil and sedimentary PCDD/Fs from China were comparable to or less than those in Korea. The patterns of relative concentrations of individual congeners in soils were different between the two countries, but similar in sediments. Sources of PCDD/Fs in China and Korea were found to be independent of each other and their distributions reflected matrix-dependent accumulation. Spatial distribution indicated some point sources in Korea while Chinese sources were more widespread and diffuse. PCDD/Fs measured in the coastal areas of the Yellow Sea were comparable to or less than those previously reported in for eastern Asia. However, ∑TEQs in soils and sediments were near to or, in some cases exceeded environmental quality guidelines.

Historical trends of polychlorinated dibenzo-p-dioxins and dibenzofurans in three dated sediment cores from Mexico

This paper describes the first report of dioxins and furans (PCDDs/Fs) in sediment cores from Mexico. Sedimentation rates and vertical fluxes were estimated using (210)Pb dating. Two cores correspond to marine sediments and one to an endorheic lake. Concentrations of PCDDs/Fs found in the three sites are typical of non-impacted areas with low concentrations when compared to reference values. However the PCDDs/Fs sediment profiles show an increasing concentration trend in the upper core sections. This behavior is different from that found at many sites around the globe where diminishing concentrations have been reported. A strong predominance of OCDD was observed, and a comparison to typical composition profiles of industrial and other sources did not result in clear origin assignments for these measured compounds. We suggest that local sources may be responsible for the increase in concentration and, because these undetermined sources have not been curtailed, their importance is still growing.

PCDD/Fs in sediments of Central Vietnam coastal lagoons: in search of TCDD

Samples from nine Central Vietnam coastal lagoons, together with three soils and sediments collected in two freshwater reservoirs of the Thua Thien-Hué province, were analysed for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Total concentrations are low, from 192 to 2912 pg g(-1) and depth profiles in Tam Giang-Cau Hai (TG-CH) sediment cores show only minor changes over time in PCDD/F input and composition. Octachloro dibenzo-p-dioxin (OCDD) is the prevailing congener (approximately 90%), indicating combustion as the main PCDD/F source to these coastal systems, whereas natural formation might be partly responsible for the presence at depth. 2,3,7,8-Tetrachloro dibenzo-p-dioxin (TCDD), largely sprayed together with Agent Orange over the study areas during the war (1961-1971), is absent or very low. This result supports the hypothesis of strong degradation soon after spraying. Multivariate statistical analyses account for the presence of local, short-range sources as observed in the northern part of the TG-CH lagoon.

Dioxin transfer from sediment to the infaunal surface deposit-feeding polychaete Perinereis nuntia in a laboratory-rearing experiment

In the presented study a laboratory experiment was conducted to investigate the transfer of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (PCBs) from environmentally contaminated marine sediment to an infaunal surface deposit-feeding polychaete, Perinereis nuntia. Polychaetes were exposed to contaminated sediment for 42 d, and elimination of these compounds was studied for an additional 28 d. The sediment uptake rate coefficients (ks), elimination rate constants (k2), and the biota-sediment accumulation factors (BSAFs) were determined for PCDDs, PCDFs (PCDD/Fs), and dioxin-like PCBs. Each of these compounds was transferred from sediment to polychaete except for hepta- and octachlorinated PCDD/Fs. The BSAFs for dioxin-like PCBs (0.13-2.2) were significantly higher than those for PCDD/Fs (0.00022-0.36). The BSAF, ks, and k2 values obtained in the present study indicate that the bioaccumulation characteristics of PCDD/Fs in polychaete are similar to those in fish, and depend on their physical and chemical properties such as hydrophobicity and size of molecules. The ks values for PCDD/Fs and dioxin-like PCBs declined with an increase in their log KOW values, indicating a decrease in bioavailability. The negative exponential relationships of k2 versus KOW were observed for these compounds. The slope for the log-normalized regression of k2 versus KOW for the PCDD/Fs was smaller than that for the dioxin-like PCBs and that of ks versus KOW for the PCDD/Fs. Therefore, the negative exponential relationship of BSAF versus KOW was observed for PCDD/Fs, but not for dioxin-like PCBs.

Spatial, phase, and temporal distributions of perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) in Tokyo Bay, Japan

The spatial distribution, partitioning, and time trends of perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) were investigated in the water column and bottom sediment of Tokyo Bay, Japan, during 2004-2006. A total of 480 water and 60 sediment samples obtained by regular 20-station samplings ascertained the three-dimensional distributions of these compounds and changes in the seawater structure in the whole bay. The median of volume-based average water-borne concentrations of PFOS and PFOA was 3.7 and 12 ng/L, respectively. The median concentrations in sediment were 0.61 (PFOS) and 0.20 (PFOA) ng/g-dry. Vertical mixing of the water column probably affected the vertical distribution of these compounds. The negative correlations between PFOS and PFOA concentrations and water salinity and the horizontal distributions of their concentrations suggested that freshwater inputs into the bay were the source of these compounds. A mixing model estimated the average PFOS concentration in the freshwater inputs to be 29 ng/L. The common logarithm of the partition coefficients between the dissolved and suspended-particle-sorbed phases varied among samples, with the average of 4.2 (PFOS) and 3.5 (PFOA). Our analyses indicated no apparent time trends in the concentrations of these compounds during 2004-2006 in either the freshwater input or the bay.

Polychlorinated dibenzo-p-dioxin, polychlorinated dibenzofurans and polychlorinated biphenyls in farmed fish, water, sediment, and feed

This investigation was undertaken to determine the levels of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dizenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (DL-PCBs) in farmed grouper tissues and environmental medium samples, including sediment, water, and feed. The water concentrations of DL-PCBs were low at 4.33-7.63 pg/L, and those of PCDD/Fs were 0.399-0.794 pg/L. The concentrations of PCDD/Fs in sediment samples were 21.4-35.3 pg/g, and those of PCBs were 54.7-100 pg/g. To identify changes in PCDD/Fs and PCBs levels in fish throughout growth, the tissue samples from hatchlings, 2-month, 15-month, 24-month, and 36-month-old orange spotted grouper (Epinephelus coioides) were analyzed. In grouper tissue samples, the total toxicity equivalent (TEQ) of the total PCBs were 0.129-0.745 pg World Health Organization- toxicity equivalent (WHO-TEQ/g) wet weight (w.w.), while total PCDD/Fs TEQ were 0.022-0.073 pg WHO-TEQ/g w.w The DL-PCBs were contributed more to the TEQ than PCDD/Fs in all fish tissue samples. Both PCDD/F and DL-PCB concentrations increase as grouper age increased. Results of this study demonstrate that PCDD/Fs and PCBs accumulate in fish tissues, and diet is the main source of PCDD/Fs and PCBs accumulations.

Polychlorinated dibenzo-p-dioxins and dibenzofuran contents in fish and sediment near a pentachlorophenol contaminated site

Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in sediment and fish of aqua farms close to a contaminated site of a pentachlorophenol production plant (CPDC-ASS) were investigated. The total PCDD/F I-TEQ level in sediment and fish ranged from 0.725 to 87.9 ng I-TEQ kg(-1)d.w.(-1) and 0.044 to 3.10 pg I-TEQ g(-1)w.w.(-1), respectively, meaning that the CPDC-ASS was a long-term exposure PCDD/F contaminated area. The four dominant congeners in sediment and fish were OCDD, OCDF, 1,2,3,4,6,7,8-HpCDF and 1,2,3,4,6,7,8-HpCDD. The correlated coefficient of total I-TEQ PCDD/F contents between fish and sediment was 0.82 (R(2)), indicating a positive correlation between exposure to PCDD/Fs in sediment and biota. In addition, the biota-to-sediment accumulation factors (BSAFs) values of low chlorinated PCDD/F congeners such as those of 2,3,7,8-TeCDD for Milkfish and Tilapia were 0.00739 and 0.00593, respectively, which were much higher than those of highly chlorinated congeners. For example, the BSAFs of OCDD for Milkfish and Tilapia were 0.000207 and 0.000277, respectively. A negative relationship of log K(ow) and log BSAF for PCDD/F congeners was found, and the highest value was observed at approximately K(ow)= 7.0-7.5. The results of this study provide valuable information for establishing the PCDD/F regulated standard for the sediment of fish ponds.

Understanding the performance of different lichen species as biomonitors of atmospheric dioxins and furans: potential for intercalibration

The aim of this study was to compare the performance of two lichen species--Xanthoria parietina and Ramalina canariensis--as biomonitors of the toxic organic compounds dioxins and furans (PCDD/Fs). For that purpose, the concentrations and profiles of PCDD/Fs found in samples of these two lichen species were compared. Results showed that R. canariensis presented higher concentrations than X. parietina and that the PCDD/F homologue profiles were substantially different between these species. Xanthoria parietina appeared to be a more efficient interceptor of more chlorinated PCDD/Fs and also of particles, whereas R. canariensis mainly reflected less chlorinated PCDD/Fs. Results also showed that the PCDD/F profile of X. parietina differed from the one found in other foliose and fruticose lichen species. Despite the differences observed between the profiles of R. canariensis and X. parietina, the calibration of PCDD/F concentrations between the two species was achieved, allowing the biomonitoring of PCDD/Fs at a regional scale using both species simultaneously.

Mass loading and partitioning of dioxins in irrigation runoff from Japanese paddy fields: combination usage of the CALUX assay with HRGC/HRMS

Lack of understanding of dioxins mass loading into the aquatic environment motivated the quantitative investigation of dioxins runoff from paddy fields during one entire irrigation period in the Minakuchi region, Japan. Combination use of the chemically activated luciferase gene expression (CALUX) bioassay together with high resolution gas chromatography and high resolution mass spectrometry (HRGC/HRMS) enabled efficient investigation of dioxins contamination. The result shows that the congener profile in irrigation runoff is quite similar to those in paddy soil samples and that 1,3,6,8-/1,3,7,9-TeCDD and OCDD derived from pesticides (i.e., pentachlorophenol (PCP) and chloronitrophen (CNP)) are predominant congeners in irrigation runoff. Although it is not surprising that dioxins concentration was strongly dependent on the suspended solids (SS) and the particulate organic carbon (POC) concentration, the dioxins toxic equivalency (TEQ) concentration was extremely high in irrigation runoff (max: 16,380 pg/L, corresponding to 12 pg WHO-TEQ/L) due to runoff of highly contaminated paddy soils. The results imply that dioxins concentration in a river must be monitored considering soil contamination level, land use, and soil runoff events. Using experimental data and a theoretical model, the mass loading of dioxins from the paddy fields by irrigation runoff was estimated to be 1.50 x 10(-2)% of total amount of dioxins accumulated in the paddy fields. Given the results of other researches, it is implied the following: 1) large portion of paddy soils released into the river appear to be settled on the riverbed due to small water flux, and, then, washed out and transported by rainfall runoff after irrigation period, 2) rainfall runoff itself also wash out paddy soils directly from paddy fields. Combination use of the CALUX bioassay with HRGC/HRMS is demonstrated as an alternative strategy to assess dioxins contamination in the environment.

Particle-size-fractioned transfer of dioxins from sediments to water columns by resuspension process

Particle-size-fractioned transfer of dioxins from sediments to water columns by resuspension process was investigated, using supernatant samples obtained from shaking experiments of sediment-water pairs simulating natural disturbances. The concentrations (dry-matter mass basis) of individual compounds (C(fraction)) in two particle size fractions (0.1-1 and 1-10 microm) in the supernatants were generally slightly higher than those in the original sediment (C(sed)). C(fraction)/C(sed) ratios ranged from 0.45 to 5.9 (median 1.5) without consistent differences among congener groups or consistent correlations against the number of chlorine atoms. The dioxin concentrations in the water column associated with the remaining sediment particles can therefore be estimated by those in the original sediment and by the concentration of suspended sediment particles in the water. The concentration of each compound in the remaining sediment particles (mostly 0.1-10 microm in size) can be roughly estimated by multiplying the concentration in the original sediment by 1.5.

Distribution of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/Fs) and dioxin-like polychlorinated biphenyls (dioxin-like PCBs) in the soil in a typical area of eastern China

The distribution and concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dioxin-like PCBs, also called co-PCBs) in a typical area of eastern China were evaluated by analysis of 21 soil and 6 sediment samples. The range of WHO-TEQ values for the PCDD/Fs and dioxin-like PCBs in 17 soil samples representing the background investigation in the study area was 0.017-5.04 pg g(-1) (dry weight, dw), with a mean value 0.967(+/-1.361)pg g(-1) and medium value 0.348 pg g(-1), which indicates that the levels of PCDD/Fs and dioxin-like PCBs over the major part of this district were low. However, the WHO-TEQ values (6.52-16.7 pg g(-1) dw) for PCDD/Fs and dioxin-like PCBs in soil samples to the leeward of a known contaminated disassembly industrial park were much higher than that of the background investigation, and the levels of sediment samples downstream of this area were in the range 2.25-34.6 pg g(-1) (dw). The levels of WHO-TEQ in soil and sediment samples decreased with an increase in distance from the researched pollution source. The principal component analysis demonstrated that the PCDD/Fs and dioxin-like PCBs in major part of contaminated sediment and soil samples derived from the correlative matrix. Yet the different distribution patterns of them in part of sediment samples strongly indicate that other potential sources may be exist, further researches should be done to get more information about the sources and the distributions of the PCDD/Fs and PCBs.

Polychlorinated dibenzo-p-dioxins/furans and polychlorinated biphenyls in human adipose tissue from Zhejiang Province, China

This is the first report on polychlorinated dibenzo-p-dioxin/furan (PCDD/F) and polychlorinated biphenyl (PCB) contamination of human adipose tissue from China. A total of 24 human adipose tissue samples from a general population in Zhejiang Province were analyzed for PCDD/F and PCB by high-resolution gas chromatography-high-resolution mass spectrometry. Total PCDD/F concentrations in human adipose tissue ranged from 33.9 to 504 pg g(-1)lipid (mean 108 pg g(-1)lipid). Corresponding values for dioxin-like PCBs ranged from 4.1 to 125 ng g(-1)lipid (mean 32.8 ng g(-1)lipid). Mean total WHO toxicity equivalent (TEQ) values for PCDD/Fs and PCBs in human adipose tissue were 9.22 and 16.2 pg g(-1)lipid, respectively. OCDD was the dominant PCDD/F congener, and 2,3,4,7,8-PeCDF and 1,2,3,7,8-PeCDD accounted for more than 70% of the WHO PCDD/F TEQ. In all samples, PCB-118, PCB-156 and PCB-105 were the main PCB congeners. PCB-153 concentrations were the highest of all indicator PCBs (mean 52.5 ng g(-1)lipid). The contamination levels and profiles are compared with those reported for European and Asian countries.

Spatial and temporal trends of PCDDs and PCDFs in bivalve mollusc coming from Galicia (2000-2005). Possible relationship between biometric parameters and PCDDs and PCDFs levels

Levels and specific profiles of PCDD/F congeners were determined in bivalve mollusc coming from several Rías (estuarine bays) in Galicia (Spanish northwest Atlantic coast). Three species of bivalve mollusc, Mytilus galloprovincialis, Cerstoderma edulis and Ostrea edulis, from several points of littoral collected in the period from 2000 to 2005 were analysed. WHO-TEQ concentrations ranged from 0.08 to 1.62 pg g(-1) wet weight, values below the maximum concentration established by the EU. The PCDD/PCDF congeners profile in the studied samples was dominated by 2,3,7,8-TCDF and 2,3,4,7,8-PeCDF. The possible influence between biometric parameters (fat and condition index) and the culture type of mussel (wild or raft) on PCDDs and PCDFs levels were studied using statistical analysis. The coefficients of Pearson product-moment correlation indicated the existence of positive significant relationship between 2,3,7,8-TCDF and 2,3,4,7,8-PeCDF levels and fat content. There was not correlation between condition index and PCDD/Fs content. ANOVA also revealed there were significant differences between SigmaPCDD/Fs, 2,3,7,8-TCDF and 2,3,4,7,8-PeCDF levels in raft and wild mussels. Spatial and temporal trends were supported by patterns in ANOVA, using a general linear model (GLM) showing a clear separation in the composition of these compounds in more and less contaminated Rías and a decrease of PCDD/FS levels along the years.

How do the partitioning properties of polyhalogenated POPs change when chlorine is replaced with bromine?

Information about the mobility and the partitioning properties of brominated persistent organic pollutants, the environmental levels of which are sometimes higher than those of the chlorinated analogues, is limited. We estimated n-octanol/ water (log K(OW)), n-octanol/air (log K(OA)), and air/water (log K(AW)) partition coefficients for 1436 chloro- and bromo-analogues of dibenzo-p-dioxins, dibenzofurans, biphenyls, naphthalenes, diphenyl ethers, and benzenes by employing quantitative structure-property relationship (QSPR) techniques. The searches for similar partitioning patterns were performed by means of two-dimensional cluster analysis. Five classes of compounds were identified. Each of the class is characterized by similar partition coefficients and, in consequence, similar environmental properties. Finally the data was fitted into a simple multimedia model involving the partitioning map. In addition, we found thatthe changes in the partition coefficients upon the replacement of chlorine with bromine were constant: 0.11, 0.31, and -0.21 per bromine atom for log K(OW), log K(OA), and log K(AW), respectively. On the basis of this observation, a method for rapid estimation of changes in the partition coefficient upon chlorine-bromine substitution was proposed.

Source identification of PCDD/Fs in agricultural soils near to a Chinese MSWI plant through isomer-specific data analysis

Isomer-specific data were investigated in order to identify the sources of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in agricultural soils, including Fluvo-aquic and paddy soils, in the vicinity of a Chinese municipal solid waste incineration (MSWI) plant. Homologue and isomer profiles of PCDD/Fs in soils were compared with those of potential sources, including combustion sources, i.e., MSWI flue gas and fly ash; and the impurities in agrochemicals, such as the pentachlorophenol (PCP), sodium pentachlorophenate (PCP-Na) and 1,3,5-trichloro-2-(4-nitrophenoxy) benzene (CNP). The results showed that the PCDD/F isomer profiles of combustion sources and agricultural soils were very similar, especially for PCDFs, although their homologue profiles varied, indicating that all the isomers within each homologue behave identically in the air and soil. Moreover, factor analysis of the isomer compositions among 33 soil samples revealed that the contamination of PCDD/Fs in agricultural soils near the MSWI plant were primarily influenced by the combustion sources, followed by the PCP/PCP-Na and CNP sources. This implication is consistent with our previous findings based on chemometric analysis of homologue profiles of soil and flue gas samples, and identifies PCP/PCP-Na as an additional important source of PCDD/Fs in the local area. This makes the similarities and differences of isomer profiles between Fluvo-aquic and paddy soils more explainable. It is, therefore, advisable to use isomer-specific data for PCDD/F source identifications where possible.

Assessing dioxin precursors in pesticide formulations and environmental samples as a source of octachlorodibenzo-p-dioxin in soil and sediment

An as yet unidentified origin of elevated concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) in soil and sediment has repeatedly been described from different locations around the world, including Australia. Natural sources have been hypothesized to account for such contamination, which is characterized by a distinctive dioxin profile, in particular, elevated levels of octachlorodibenzo-p-dioxins (OCDD) as well as relatively low contributions of polychlorinated dibenzofurans (PCDFs). The present study investigated whether OCDD formation via anthropogenically derived precursors represents a possible source in such samples. Soil and sediment from Australia and Hawaii were screened for known pesticide derived dioxin precursors. Two pesticide formulations containing pentachlorophenol (PCP), which are well-known to contain predominantly OCDD impurities, were also analyzed. Polychlorinated phenoxyphenols (PCPPs), common byproducts of pesticide production, were detected at parts-per-billion (ppb) levels in two PCP formulations and in five environmental samples. Of particular interestwasthe presence of the PCPP isomer 3,4,5,6-tetrachloro-2-(2,3,4,5,6-pentachlorophenoxy)phenol (nonaC2PP), often also termed predioxin, in these samples. This compound readily undergoes ring closure to form OCDD under a range of conditions and environments. In addition, the pesticide PCP itself, which also represents a potent precursor to OCDD formation and is known to contain OCDD impurities, was detected in some environmental samples. The evidence from this study indicates that pesticides and their impurities play an important role in the dioxin contamination of Australian soils and sediments, as well as other locations with similar PCDD/F patterns. The results further suggest that formation of OCDD from pesticide derived precursors may be a possible past, present, and future pathway for contamination of environmental samples.

Distribution characteristics and source analysis of dioxins in sediments and mussels from Qingdao coastal sea

Seven of surface sediments, one sediment core and two mussel samples were collected from the Qingdao coastal sea of the western Yellow Sea and analyzed to determine the horizontal distribution, deposition flux, and toxicity equivalency (TEQs) of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). The total PCDD/Fs concentrations in the surface sediments ranged between 10.7 and 428 ng kg(-1) dry wt. The horizontal distribution of PCDD/F congeners in the sediments was characterized by elevated concentrations at the locations in the east of Jiaozhou Bay with the highest concentration occurring near the Haibo River mouth. Physical parameters (total organic carbon contents and sediment types) and the current circulation systems in Jiaozhou Bay can be important factors controlling the horizontal distribution pattern of PCDD/Fs in the bay. The influence of the Haibo River as a source of pollution was evidenced by PCDD/F homologue profiles, indicating a contribution from sewage sludge in addition to other possible sources. Records from the sediment core revealed that the total PCDD/Fs in the Qingdao coastal sea were nearly constant since 1951 till 1980s and increased remarkably after 1980s. The total 2,3,7,8-substituted PCDD/Fs and total TEQs of PCDD/Fs on the lipid basis in the mussel sample inside the bay were significantly higher than in the adjacent sediment. The homologue profiles of PCDD/Fs in the mussels were quite different from those of the sediments, characterized by high TCDF (50% of the total PCDD/Fs).

Levels of polychlorinated dibenzo-p-dioxins and dibenzofurans in China and chemometric analysis of potential emission sources

Aimed to give a preliminary image of dioxin pollution in China, chemometric analysis was performed to determine background dioxin levels during the period 1994-2002 and potential emission sources. Using principal components analysis (PCA), the congener profiles of 71 sediment samples from rivers, lakes, and sea bays around China were compared with the congener profiles of various known or suspected industrial, residential, and municipal dioxin sources to determine whether the dioxin residues typically found in a broad range of potential environmental sources could explain the presence of these chemicals in China. It was found that the background dioxin levels of China were similar to those of lightly polluted samples from other countries during the period 1994-2002. Primary ferrous ore sintering and secondary lead and aluminum smelters were the major sources of dioxin emission in China. Chloranil and wastewater from chemical plants, sodium pentachlorophenate, and pulp bleaching were also important sources of dioxin emission. Open burning of e-waste as well as diesel-fueled and leaded gas-fueled vehicles were additional possible sources of dioxin. In contrast to other countries, in China, flue gases from incineration of municipal waste, hazardous waste, and medical waste might be minor sources of dioxin emission.

Polychlorinated dibenzo-p-dioxins, dibenzofurans, and dioxin-like polychlorinated biphenyls in sediment and mussel samples from Kentucky Lake, USA

Sediment and mussel tissues from the Kentucky Dam Tailwater (KDTW) and Ledbetter Embayment (LE) of Kentucky Lake, Kentucky, USA, were analyzed to examine the presence of 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and non-, mono-, and di-ortho-chlorine-substituted polychlorinated biphenyls. Concentrations of target compounds varied with locations and sample matrices. In general, KDTW sediment samples contained slightly higher amounts of PCDD/DFs (average: 1100, range: 120-2400) than the LE sediments (average: 920, range: 580-1300) on a pg/g dry wt (dw) basis. Dioxin-like PCBs in KDTW were (average: 550, range: 70-2,000) higher than in LE (average: 320, range: 44-1000) on a ng/g dw basis. In contrast, mussel tissues had greater concentrations of PCDD/DFs in LE (average: 6500, range: 2200-13,000) than in KDTW (average: 3500, range: 2500-4800). Dioxin-like PCBs were slightly higher in KDTW (average: 76, range: 18-100) than in LE (average: 49, range: 24-96) on a ng/g fat wt basis. Biota sediment accumulation factors (BSAFs) were calculated using tissue concentrations and sediment concentrations based on dry weight. PCDD/DFs BSAF was in the range of 0.21-25 in LE and 0.093-13 in KDTW. 1,2,3,7,8,9-HxCDF in LE and 2,3,7,8-TCDF in KDTW had a greater BSAF, while BSAF for dioxin-like PCBs ranged from 0.84 to 13 in LE and from 2.3 to 12 in KDTW in which PCB-169 had the greatest BSAF in LE and PCB-167 in KDTW. Toxic equivalency (TEQ) was greatest in mussel from LE (mean: 193 pgTEQ/g fat wt) followed by mussel from KDTW (32 pgTEQ/g fat wt), sediment in KDTW (13 pgTEQ/g dry wt), and sediment in LE (7.6 pgTEQ/g dry wt). In general, PCDD/DF had a greater contribution to toxicity in mussels, while dioxin-like PCBs had a greater contribution to toxicity in sediment at both locations.

Fingerprinting localized dioxin contamination: Ichihara Anchorage case

Although concentrations of polychlorinated dibenzo-p-dioxins and dibezofurans (PCDD/Fs; dioxins) in majority of Japanese river and ocean sediments decreased below the national environmental quality standard of 150 pg-TEQ. (g-dry sediment)(-1) by 2004, localized contamination inasmuch as 100-fold excess of the environmental quality standard has been reported at various locations including Ichihara Anchorage in northeastern Tokyo Bay. In the present study, we analyzed all mono- to octachlorinated dioxins in 12 surface sediments from Ichihara Anchorage and applied positive matrix factorization (PMF) to quantitatively fingerprintthe congener pattern and geographical distribution of a factor causing the localized contamination. A PMF-derived fingerprint attributable to dioxin impurities in pentachlorophenol (PCP) exerted more than 90% contribution to total dioxin concentrations in Ichihara Anchorage surface sediments. Although majority of Ichihara Anchorage-born dioxins were trapped at the origin, contribution of the PCP-derived dioxins in overall Tokyo Bay gradually increased toward Ichihara Anchorage, indicating the impact of localized dioxin contamination on a large proportion of Tokyo Bay. We suggest that, in addition to runoff from rice paddies (to which PCP had long been applied as herbicide) at the basin, Ichihara Anchorage serves as a significant source of PCP-derived dioxins especially in eastern Tokyo Bay.

PCB, PCDD/F and PBDE levels and profiles in crustaceans from the coastal waters of Brittany and Normandy (France)

Polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were analysed in the muscle of various edible marine crustaceans (spider crab, edible crab, velvet swimming crab and Norway lobster) from the Brittany and Normandy coasts (France). The highest concentrations were measured in species collected from Antifer (Seine Bay). PCB and PBDE patterns in crustacean muscles were similar and independent of the geographical area with the predominance of the high chlorinated PCBs (CB153, 138, 118 and 180), and of a few PBDE congeners (BDE47, BDE99, BDE100 and BDE28). Oppositely, dioxin contamination differed with site. The major component in crustaceans from the Seine Bay was 2378-TCDF, whereas specimens from cleaner areas had higher relative concentrations of OCDD. Finally, the comparison of the spider crab contaminant profiles to those measured in mussel and sea bass highlighted two different trends: decapod crustaceans possess relatively strong capacity to metabolise PCBs and PBDEs; however these species might be used as bioindicators for dioxin pollution monitoring in the marine coastal environment.

Polychlorinated dibenzo-p-dioxins/furans and polychlorinated biphenyls in fresh fishes from Qiantangjiang River, China

Muscles of two species of fish collected in Qiangtangjiang River were analyzed for polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) by high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS). Average concentrations of total PCDD/Fs in Crucian carp and White Amur bream were 1.14-7.88 pg g(-1)ww and 1.02-8.18 pg g(-1)ww respectively. Corresponding values for PCBs were 469.36-10972 pg g(-1)ww and 364.79-4948.0 pg g(-1)ww. Average total WHO-TEQ of Crucian carp and White Amur bream from five areas ranged from 0.25 to 2.33 pg g(-1)ww and 0.30 to 1.70 pg g(-1)ww. The contamination level was compared with other studies and risk assessment was discussed.

Time trends in sources and dechlorination pathways of dioxins in agrochemically contaminated sediments

Although polychlorinated dibenzo-p-dioxins and dibezofurans (PCDD/Fs) are considered recalcitrant toward biotic and abiotic degradation processes, laboratory studies indicated lateral dechlorination pathways (removal of 2,3,7,8-substituted chlorines) as possible natural remediation strategies under highly reducing conditions prevailing in contaminated sediments. Previous principal component analysis (PCA) of PCDD/Fs in Japanese sediments left unidentified a factor characterized by penta- to octa- homologues fully chlorinated at 1,2,6,9-positions (1,2,6,9-pattern). In the present study, we reexamined PCDD/Fs in sediment cores from urban (Tokyo Bay) and remote (Lake Shinji) areas of Japan using positive matrix factorization (PMF) and revealed a lateral dechlorination fingerprint exhibiting the 1,2,6,9-pattern. Relative molar concentrations of putative lateral dechlorination products linearly increased with sediment depth, suggesting that decades of reaction resulted in the accumulation of hepta- and hexa- chlorinated lateral dechlorination products in the bottom sediment layers. Times required for in situ formation of dechlorination products were estimated to be at least 27.8 +/- 17.9 year(mole %)(-1) in Lake Shinji and 4.7 +/- 0.5 year(mole %)(-1) in Tokyo Bay (both for the formation of 1,2,3,4,6,7,9-HpCDD) and are significantly longer than the dechlorination pathways observed in the laboratory.

PCDD/F contamination over time in Japanese paddy soils

Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs)were analyzed in preserved paddy soils periodically collected from 7 sites around Japan since 1960 to trace the changes in concentrations, to elucidate their sources, and to estimate their mass balance in Japanese paddy fields. Concentrations of sigma PCDD/Fs in paddy soils from all sites increased during the 1960s and the 1970s, then decreased. The results of principal component analysis and chemical mass balance based on functional relationship analysis indicate that the increase in sigma PCDD/F concentrations in paddy soils was due to the increased use of pentachlorophenol (PCP) and chlornitrofen (CNP); more than 95% of PCDD/Fs in all paddy soils were derived from impurities in these herbicides. The half-lives of PCDD/F for disappearance from the paddy soils were estimated to be 10 to 20 years (mean: 17.3 years). The estimated PCDD/F mass balance using the above half-life during the past 40 years in paddy fields indicates that about 80% of PCDD/Fs have disappeared. The soil puddling (mechanically mixing of paddy soil with pooled irrigation water) is implied as one reason for the PCDD/F disappearance from paddy fields. However, as the amounts of PCDD/Fs added through the use of PCP and CNP were extremely large, PCDD/F concentrations in Japanese paddy soils will decrease gradually, and PCDD/F runoff from paddy fields to surrounding catchments will continue.

Dioxin concentrations in sediments of the Baltic Sea--a survey of existing data

Recent survey results for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs, dioxins) in Baltic Sea sediments from Finland, Sweden and Denmark were merged with previously published Baltic Sea data. Regional distribution of concentration levels, differences in congener patterns, and temporal changes in sediment profiles were examined. One of the main objectives was to study if any major point sources for different PCDD/F congeners could be identified on a regional scale, based on sediment records. The survey confirmed the impact of chlorophenol production derived highly chlorinated PCDF-congeners on the total toxicity in sediments in the Gulf of Finland near the Kymijoki river estuary. Signatures of other point sources or combined point sources pertinent to specific industry branches or particular production processes (such as pulp bleaching, vinyl chloride production, thermal processes) may be discerned. However, the findings did not support any of the known point sources significantly influencing those congeners that are most abundant in Baltic herring and salmon. Instead, regional distributions in the Baltic Sea indicate that atmospheric deposition may act as a major source for those congeners and especially for 2,3,4,7,8-PeCDF. There were clear indications of declines in levels in sediment in some areas, but generally the levels of highly chlorinated PCDD/Fs on the northern coast of the Gulf of Finland were still high when compared with other areas of the Baltic Sea. Major areas with data gaps cover the south-eastern and eastern coastal regions of the Baltic Proper and the southern Gulf of Finland.

Polychlorinated dibenzo-p-dioxins and dibenzofurans in paddy soils and river sediments in Akita, Japan

Paddy soils and sediments from the Yoneshirogawa, Omonogawa, and Koyoshigawa River Basins in Akita were analyzed for polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). The levels and compositions in those samples including soils from non-agricultural areas (non-agricultural soils) were investigated using isomer-specific analysis to determine characteristic sources. The PCDD/PCDF compositions in the samples were compared with respect to possible sources. The PCDD/PCDF concentrations in paddy soils were much higher than those in the non-agricultural soils and much higher than those found in other parts of Japan. Although PCDD/PCDFs were ubiquitous in sediments from river sources to mouths of the respective river basins, those concentrations were much lower than those from paddy soils and non-agricultural soils, and from other parts of Japan. Comparison of PCDD/PCDF homologues and isomer compositions for samples indicated that compositions of paddy soils and sediments, except for those from river sources, had similar characteristics to PCDD/PCDFs originating from impurities in herbicides, 2,4,6-trichlorophenyl 4-nitrophenyl ether (CNP) and pentachlorophenol (PCP), and that compositions of river-source sediments and non-agricultural soils resembled those of atmospheric depositions. Results of statistical analyses suggest that PCDD/PCDF contamination of paddy soils and sediments is attributable mainly to three sources: CNP, PCP, and atmospheric deposition. Results of this study also demonstrate that CNP and PCP are not only important contaminants of local areas of Japan, but that they exist throughout Akita, in northern Japan. We therefore conclude that PCDD/PCDF pollution caused by those compounds has a widespread influence on paddy soils and river sediments in Japan.

Polychlorinated dibenzo-p-dioxin and dibenzofuran concentrations in common fish species in the Pearl River Delta area, China

Polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/Fs) concentrations in 31 fish samples from 19 commonly consumed freshwater and saltwater species from the Pearl River Delta Area were analyzed. The PCDD/Fs dietary intake from fish for the local population was evaluated to provide a database for setting the national PCDD/F limits in fish for the People's Republic of China. The median concentration from the 31 fish samples was 1.27 pg/g wet weight for the total of PCDD/Fs, and the median WHO-TEQ was 0.26 pg/g wet weight, and ranged from 0.063 to 1.30 pg WHO-TEQ/g wet weight. The dominant contributors to the WHO-TEQ were 1,2,3,7,8-PeCDD and 2,3,4,7,8-PeCDF, which accounted for 38% and 28%, respectively. The dietary intake of PCDD/Fs from fish for local people was estimated to be 0.47 pg WHO-TEQ/kg bw x day. In view of the findings, the dietary of PCDD/Fs from other foods of animal origins in China should be studied in more detail as soon as possible in order that standards can be put forward to protect human health.

Monitoring of polychlorinated dibenzo-p-dioxins and dibenzofurans, dioxin-like PCBs and polycyclic aromatic hydrocarbons in food and feed samples from Ismailia city, Egypt

Concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyl (PCBs) and polycyclic aromatic hydrocarbons (PAHs) have been determined using GC/HRMS in food (butter, seafood and meat) and feed samples (chicken, cattle and fish) purchased from Ismailia city, Egypt. PCDD/F concentrations in food samples ranged between 0.12 and 3.35 pg WHO TEQ/g wet w, while those in feed samples were between 0.08 and 0.2 pg WHO TEQ/g dry w. Levels of PCB TEQ ranged from 0.14 to 3.2 pg/g wet w in the food samples. The feed samples have an average of 0.35 pg PCB TEQ /g dry w. In this study, butter samples showed the highest contamination levels of PCDD/Fs and PCBs. The PCBs contribution to the total TEQ was on average 63% in seafood and on average 49% for meat and butter. The highest contamination levels of PCDD/Fs and PCBs were found in butter samples. The butter TEQ content is several times higher than that reported in all EU countries and exceeded the EU limits, while the PCDD/F levels in seafood and the feed samples is far below the current EU limit. Generally, congener profiles in the food samples reflect the non-industrialized nature of the city and suggest solid waste burning as a significant source of emission. Nevertheless, the profiles for butter suggest an impact from various sources. In the case of the sum of 16 PAH contamination levels in food samples were in the range of 11.7-154.3 ng/g wet w and feed samples had a range of 116-393 ng/g dry w. Benzo(a)pyrene (BaP) has been detected in the range of 0.05-3.29 ng/g wet w in the food samples; butter showed the highest contamination which exceeded the EU standard set for fats and oil. Fingerprints of PAHs suggested both petrogenic and pyrolytic sources of contamination.

Horizontal distribution of steroid estrogens in surface sediments in Tokyo Bay

A monitoring survey was conducted to investigate the distribution of steroid estrogens and their conjugates in surface sediments of Tokyo Bay for the first time, which is known as one of the most heavily polluted marine embayments in the world. The surface sediment samples were collected at 20 locations covering the whole area of Tokyo Bay and analyzed for steroid estrogens and their conjugates using liquid chromatography-tandem mass spectrometry. The concentrations of 17beta-estradiol (beta-E2) and estrone (E1) ranged from ND (below the detection limit; <0.07) to 0.59 and from 0.05 to 3.60 ng g-1 dry, respectively. Those concentrations were higher in the northern part of the bay, which is directly receiving huge quantities of pollutants from adjacent rivers containing a large amount of municipal and industrial wastewater. 17alpha-Estradiol (alpha-E2) and estrone-3-sulfate (E1-3S) were detected in some of the samples, whereas neither of the other conjugates, estriol (E3) or 17alpha-ethynylestradiol (EE2), was found.

Characterization of polychlorinated dibenzo-p-dioxins and dibenzofurans in different particle size fractions of marine sediments

The distribution of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) was examined according to particle size in marine sediments, with a particular focus on fine particulates. Samples from different coastal sites were fractionated into five size groups (<2, 2-5, 5-10, 10-20, and 20-63 microm diameter) by gravitational split-flow thin fractionation. Despite the different size profiles and PCDD/F contents of the sediments at each site, PCDD/F levels in fractionations tended to increase as the particle size decreased; the PCDD/F levels in the finest particles were up to 16 times higher than in the coarsest particles, which was associated with their organic carbon contents. Log normalization showed high levels of PCDD/Fs in the fine silt particles (2-10 microm), which are consumable by aquatic biota. Because of the different toxicity and bioavailability of PCDD/Fs in different sediment particle sizes, it is important to study particle actions to understand their effects on the aquatic ecosystem.

Organochlorine compounds (PCBs, PCDDs and PCDFs) in seafish and seafood from the Spanish Atlantic Southwest Coast

Concentrations and congener specific profiles of PCDD/Fs and PCBs were determined in edible fish and seafood species from the Coast of Huelva, in the Spanish southwest Atlantic coast. Five fish species, namely wegde sole (Dicologoglossa cuneata), common sole (Solea vulgaris), white seabream (Diplodus sargus), sardine (Sardina pilchardus), angler fish (Lophius piscatorius), two shellfish species (Donax trunculus and Chamelea gallina), common cuttlefish (Sepia officinalis) and prawns (Parapenaeus longirostris), frequently found and consumed in the area were analysed. Concentrations ranged from 861 to 23787pg/g wet weight for total PCBs, while 2,3,7,8-PCDD/Fs showed concentrations ranging from 0.2 to 1.18pg/g wet weight. WHO-TEQ concentrations ranged from 0.038 to 0.186pg WHO-TEQ(PCDD/Fs)/g wet weight, values well below the maximum concentrations established by the EU. When non- and mono-ortho PCBs were included the values increased to a maximum of 0.99pg WHO-TEQ(PCDD/Fs+PCBs)/g wet weight. The PCB and PCDD/F accumulation pattern found in the samples analysed showed a distribution typically reported for marine samples, and no remarkable differences were found between species. The PCBs were the ones contributing with the highest percentage to the total TEQ content in most species studied. Concerning the seafood, specially prawns and shellfish, the opposite was observed and PCDD/Fs were found to contribute with a higher percentage than PCBs. The congener specific contribution to the TEQ showed PCB 126 followed by 1,2,3,7,8-PeCDD and 2,3,4,7,8-PeCDF as the most abundant ones.

PCDDs, PCDFs, and coplanar PCBs in wild terrestrial mammals from Japan: congener specific accumulation and hepatic sequestration

The present study determined the contamination levels and congener-specific accumulation features of dioxins and related compounds (DRCs) in wild terrestrial mammals such as large Japanese field mice (LJFM), lesser Japanese moles (LJMs), and raccoon dogs (RDs) collected from Kanto region in Japan during 2001. The toxic equivalent quantity (TEQ) levels in the carcasses or adipose tissues were in the order of RDs > or = LJMs > LJFM. Comparison of DRC congener profiles in the three species and principal component analysis (PCA) demonstrated a higher contribution of OCDD, T4CB77, and P5CB118 in LJMs. Analysis of liver-adipose distribution of DRC congeners in RDs showed that livers contained significantly higher TEQs than adipose tissues, indicating that liver is a depository organ and critical for determining the toxicokinetics of DRCs. As for most T4, P5, H6CDD/DFs and for P5CB126, H6CB169 and mono-ortho PCB congeners, their liver/adipose concentration ratios in RDs revealed a tendency to increase with hepatic TEQ levels, suggesting TEQ-dependent hepatic sequestration.

Congener profiles of PCDDs, PCDFs, and dioxin-like PCBs in the breast milk samples in Tokyo, Japan

Exposure to dioxins has raised much public concern recently. We determined the congeners' distribution of polychlorinated-dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs) in the breast milk samples collected in Tokyo, Japan. Breast milk was taken from 240 mothers, 30 days after delivery in 1999 and 2000 in Tokyo, Japan. The actual concentration and TEQ concentration of PCDDs (14 congeners), PCDFs (15 congeners), and dl-PCBs (12 congeners), and each congener's contribution to the total TEQ level were calculated. Among all the samples, PCDDs accounted for 34.8%, PCDFs accounted for 23.5%, dl-PCBs accounted for 41.7%, which was also similar in the breast milk from the primiparae and secundiparae. The main contributors to the total TEQ with increasing percentages were 2,3,4,7,8-PeCDF, 1,2,3,7,8-PeCDD and 3,3',4,4',5-PCB (#126), and they accounted for more than 65% of the total TEQ. Detailed congener analysis in breast milk samples is effective to understand dioxin sources.

Comparison of biota-sediment accumulation factors across ecosystems

Sets of biota-sediment accumulation factors (BSAFs) for fish were compared across ecosystems for nonionic organic chemicals. The sets of BSAFs, when plotted against each other, in log-log space, formed linear relationships and demonstrated that the relative scaling or ranking of the individual BSAFs within a set are consistent, if not the same, across ecosystems. This behavior holds for chemicals that either are, or are not, metabolized by fish. These results demonstrate that sets of BSAF values can differ but with parallel shifts in magnitude between ecosystems (for example, all of the BSAFs in the set are uniformly larger in one ecosystem, while in another they all are uniformly smaller) in response to underlying differences in ecosystem conditions and parameters such as trophic level, diet of the organisms, and distribution of the chemical between the sediment and water column.

Bioaccumulation of organochlorines in crows from an indian open waste dumping site: evidence for direct transfer of dioxin-like congeners from the contaminated soil

To assess the significance of waste dumping sites as a source of chemical contamination to ecosystems, we analyzed the residue levels of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), and other organochlorines in the breast muscle of crows from a dumping site in the south of Chennai city, South India. Crows from the dumping site contained significantly higher total TEQs (60 +/- 27 pg/g lipid wt) than those from the reference sites (26 +/- 18 pg/g lipid wt). Especially, certain dioxin-like coplanar PCB congeners (Co-PCBs), such as CB-77 and CB-105, whose source is commercial PCBs,were significantly higher in crows from the dumping site than those from the reference sites. Profiles of PCDDs/DFs and Co-PCBs in crows from the dumping site were similar to those of soil at the same site, which was confirmed by principal component analysis. Furthermore, significant positive correlations were obtained between the congener-specific bioconcentration factors (BCFs) of PCDDs/DFs estimated from concentrations in crows and soil from the dumping site and the theoretical BCFs calculated from water-particle and lipid-water partitioning coefficients. On the other hand, the estimated BCFs had significant negative correlations with the molecular weight of PCDDs/DFs, indicating that molecular size limits their bioaccumulation. These results suggest that dioxin-like congeners in the soil of the dumping site were transferred directly to the crows through the ingestion of on-site garbage contaminated with soil, rather than through trophic transfer in the ecosystem. The present study provides insight into the ecological impacts of dumping sites.

Determination of polychlorinated dibenzo-p-dioxins and dibenzofurans and comparison of extraction methods for edible freshwater fish and frogs in South Korea by using a high-resolution GC/MS

Three different extraction methods were evaluated: Soxhlet extraction, accelerated solvent extractor extraction and alkali digestion with high-resolution gas chromatography/high-resolution mass spectrometry, for the analysis of edible freshwater fish and frogs. The recovery efficiencies for the different extraction methods were also compared. Using these extraction methods, the concentrations and spatial distributions of these compounds in freshwater fish and frogs (n = 99), collected from 31 locations on four major river systems (Han, Nakdong, Kum and Youngsan) and two wetlands in South Korea, were examined. The concentrations of total polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in all the freshwater fish and frog samples were analysed. The toxic equivalency (TEQ) concentration of PCDD/Fs in fish ranged from 0 (n.d.) to 1.309 pg I-TEQ g(-1) wet weight. Detailed concentrations for different types of fish were as follows (pg I-TEQ g(-1) wet weight): 0 (n.d.)-1.309 for crucian (mean 0.331, n = 28), 0.004-0.743 for carp (0.244, n = 10), 0.004-0.592 for dace (0.198, n = 8), 0.187-0.400 for cornet fish (0.287, n = 3), 0.164-0.410 for Korean piscivorous chub (0.303, n = 6), 0.105-0.516 for bass (0.310, n = 2), 0.451-0.812 for mullet (0.631, n = 2), 0.082 for long-nosed barbell, 0.100 for common Korean bitterling and 0.995 for dark chub. The total TEQ concentration ranged from 0 (n.d.) to 1.258 pg I-TEQ g(-1) wet weight for the two kinds of frogs (n = 36) investigated: 0 (n.d.)-1.258 pg I-TEQ g(-1) (mean 0.346, n = 29) for the bullfrog and from 0 (n.d.)-0.474 pg I-TEQ g(-1) (0.185, n = 7) for the mountain frog.

Concentrations and accumulation profiles of polychlorinated dibenzo-p-dioxins and dibenzofurans in aquatic tissues, and ambient air from South Korea

Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/DFs), including 2378-substituted isomers were present in samples of shellfish and fish, and ambient air collected from Masan Bay, and Masan City, South Korea. Total concentrations of PCDDs/DFs in mussel and clam were 750 pg g(-1), lipid weight (lw), and 3418 pg g(-1), lw, respectively. Total concentrations of PCDDs/DFs in mullet, gizzard and flounder were 52, 82, and 122 pg g(-1), lw, respectively. Shellfish tissues contained a greater number of PCDD/DF isomers, contributing greater total concentrations of PCDDs/DFs compared to fish collected from the same locations. The predominance of 2378-substituted PCDDs/DFs in fish is represented in greater total concentrations of 2378-TeCDD equivalents (TEQs), whereas there was very limited occurrence of 2378-substituted isomers in shellfish. TEQ concentrations in samples of mussel and clam were 0.97 and 12 pg g(-1), lw, respectively. Total TEQs in mullet, gizzard and flounder were 12, 22 and 18 pg g(-1), lw, respectively. In fish 2378-substituted PCDDs accounted for 100% of the total concentrations of PCDDs, and 2378-substituted PCDFs accounted from 59% to 73% of the total PCDFs. The 2378-substituted isomers accounted for only 3% of the total PCDDs/DFs in shellfish. Ambient air collected from two sites contained a wide range of isomers of tetra- through heptachlorinated PCDDs/DFs. Even though the total concentration of PCDDs/DFs in ambient air (12.8 pgm(-3)) collected from an industrial area was 2-fold greater than that in air samples (6.3 pgm(-3)) collected from an urban/rural area, total TEQs (0.07 and 0.08 pgm(-3)) there was no statistical difference between the two samples.

Profile analysis of organic micropollutants in the environment of a coal burning area, NW Greece

The concentrations and profiles of dibenzo-p-dioxins, dibenzofurans, polychlorinated biphenyls and polynuclear aromatic compounds in various environmental matrices are presented in this study. The examined environmental matrices are total suspended particles, fly ash and soil collected in NW Greece, an area characterized by intensive coal burning for electrical power generation. Moreover, the occurrence of organic micropollutants in soot after an accidental fire was examined and the possible impact on the outdoor environment was evaluated. Results were statistically treated to obtain information on representative PCDD/F profiles in each matrix and to compare these profiles with the compositional patterns of possible sources from literature. Coal combustion, fly ash and vehicle exhausts appeared to be the most possible sources in local atmosphere.

Dynamics of PCDDs/DFs and coplanar-PCBs in an aquatic food chain of Tokyo Bay

Concentrations and accumulation profiles of PCDDs/DFs and coplanar-PCBs (co-PCBs) in aquatic biota (e.g., plankton, shellfish, benthic invertebrate, and fish) and sediment from Tokyo Bay were examined to elucidate the relationship between bioaccumulation and trophic level in the food web as determined by the stable nitrogen isotope analysis. Bioaccumulation patterns of PCDDs/DFs and co-PCBs varied greatly among congeners. Accumulation patterns of PCDDs/DFs and co-PCBs are not solely explained by their physicochemical properties. Biota-sediment accumulation factors (BSAFs) for co-PCBs in biota from Tokyo Bay were significantly greater than those of PCDDs/DFs. Furthermore, the slopes of the plots of delta15N and BSAF values and water solubility of 2,3,7,8-substituted PCDDs/DFs and co-PCBs were highly correlated. The results of our study would provide the valuable information to understand the accumulation properties of PCDDs/DFs and co-PCBs that can be used as a scientific basis to determine the sediment quality criteria of PCDDs/DFs and co-PCBs.