Persistent organochlorine pollutants in ringed seals and polar bears collected from northern Alaska

Blubber samples from ringed seal (Phoca hispida; n = 8) and polar bear subcutaneous fat (Ursus maritimus; n = 5) were collected near Barrow, Alaska in 1996 as part of the Alaska Marine Mammal Tissue Archival Project (AMMTAP) and retained in the National Biomonitoring Specimen Bank at the National Institute of Standards and Technology in Gaithersburg, Maryland (USA). The samples were analyzed for a variety of persistent organochlorine pollutants (POPs) including polychlorinated biphenyls (PCBs), hexachlorocyclohexanes (HCHs), chlordane and metabolites, hexachlorobenzene (HCB) and DDTs and metabolites. The geometric mean, on a wet mass basis, of sigmaPCBs (sum of 29 congeners and congener groups) were 732+/-282 ng/g (1 S.D.) in seals and 3395+/-1442 ng/g in polar bears. The geometric mean of sigmaDDTs, sigmaHCHs (alpha-, beta- and gamma- HCH) and HCB concentrations (wet mass basis) in seals and bears were 562+/-261 ng/g vs. 74.8+/-39 ng/g, 380+/-213 ng/g vs. 515 ng/g, and 17.4+/-10.1 ng/g vs. 183+/-153 ng/g, respectively. The geometric mean sum of chlordane (sigmachlordane, sum of cis- and trans-chlordane, cis- and trans-nonachlor, oxychlordane and heptachlor epoxide) and dieldrin concentrations in ringed seals and polar bears were 753+/-617 ng/g vs. 720+/-315 ng/g and 38.6+/-22.8 ng/g vs. 130+/-65 ng/g, respectively. Apparent bioaccumulation factors (polar bear/ringed seal POP concentrations) were lower in the animals sampled near Barrow, Alaska than in those from locations in the Canadian Arctic. This suggests that polar bears are also preying on marine mammals from lower trophic levels than the ringed seals with correspondingly lower organochlorine levels, such as bowhead whale carcasses. PCB congener patterns in the samples demonstrated the metabolism of certain PCB congeners in the polar bear relative to the ringed seal in agreement with previous studies. Regional comparisons of animals collected in Alaska and Arctic Canada are presented.     

Bioaccumulation of polychlorinated dibenzo-p-dioxins, dibenzofurans, and dioxin-like polychlorinated biphenyls in fishes from the Tittabawassee and Saginaw Rivers, Michigan, USA

Characterizing biological factors associated with species-specific accumulation of contaminants is one of the major focuses in ecotoxicology and environmental chemistry studies. In this study, polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and non- and mono-ortho-substituted polychlorinated biphenyl (PCB) congeners were analyzed in various fish species from the Tittabawassee and Saginaw Rivers (12 fish species; n = 314 individuals), Michigan, USA. Due to their migratory habits, greater δ¹³C stable isotope values were found in walleye and white sucker among 12 fish species. Meanwhile, the δ¹⁵N values indicated that the trophic status was least in carp and greatest in largemouth bass. The greatest total concentrations of dioxins were found in fishes with the lowest trophic status (carp (n = 50) followed by channel catfish (n = 49)), and concentrations of ΣPCDD/Fs (20-440 pg/g ww (wet weight)), ΣPCBs (16-690 ng/g ww), and TEQs (6.8-350 pg/g ww) in carp were also greater than the least mean concentrations in other fishes. Contributions of various biological factors to the species accumulation were assessed. Body weight and lipid content were found to be the most significant factors influencing accumulation of ΣPCDD/Fs. Lipid content and trophic level seemed to be dominant factors determining accumulation of ΣPCB and TEQs, but negative correlations between trophic status and concentrations of ΣPCBs and TEQs were observed possibly due to the great concentrations in benthivorous fishes such as carp occupying lower trophic levels. These factors can be used to predict the contaminant levels of dioxins and health risks of the fishes in the river ecosystem.     

Dietary intake of dioxins and dioxin-like PCBs, due to the consumption of dairy products, fish/seafood and meat from Ismailia city, Egypt

Although dietary intake studies have been carried out extensively in most developed countries, to evaluate the health risks of PCDD/Fs and DL-PCBs, no data of this kind exists for Egypt. In this study, concentrations of PCDD/Fs and DL-PCBs were measured using HRGC/HRMS in the most contributing foodstuffs (dairy products, fish/seafood, and meat) randomly collected from Ismailia city, Egypt. The dietary intake of PCDD/Fs and DL-PCBs were subsequently determined, and compared with the most recent studies. To provide a primary estimation of the whole TEQ intake in Egypt if all the main food categories included, an estimation of the dietary intake (based on EU data) for some important and non-measured groups (cereals, vegetables/fruits, eggs and milk) was carried out. The calculated dietary intake based on the WHO assumption of 60 kg bw ranged from 3.69 to 4.0 pg WHO-TEQ/kg bw/day for PCDD/Fs and from, 6.04 to 6.68 pg WHO-TEQ/kg bw/day, if DL-PCBs were included. PCBs intake contributed about 40% of the total TEQ intake. Dairy products (mainly cheese) were the main contributor to the intake of PCDD/Fs (89%), while fish/seafood and meat have more or less the same percent share (5.4%). The dairy products contamination was the reason for our elevated dietary intake, as the content of PCDD/Fs and DL-PCBs is several times higher than in all the developed countries. The total intake (PCDD/Fs+DL-PCBs) due to consumption of dairy products, fish/seafood and meat, is close to that reported in EU countries at the beginning of 1980s, but much higher than all those mentioned in all the recent reports, and higher than the maximum WHO TDI of 4 pg TEQ/kg bw/day. A recalculation of the dietary intake to include not only our measured data but also the data for the non-measured groups, yielded a total intake in the range of 4.06-6.38 pg TEQ/kg bw/day for PCDD/Fs and a range of 6.59-9.98 pg TEQ/kg bw/day for total including PCBs. Results show that cereals and vegetables/fruits contribute significantly to PCDD/Fs TEQ intake in Egypt and play a more important role than fish/seafood and meat. This is the case even though the intake for cereals and vegetables/fruits based on EU data.     

Characterization of aryl hydrocarbon receptor agonists in sediments of Wenyu River, Beijing, China

Aryl hydrocarbon receptor agonistic (Ah-agonistic) effects of 23 sediments from Wenyu River in Beijing, China were evaluated using the H4IIE cell bioassay. Five samples were selected for chemical analysis of most concerned Ah-agonists, i.e. polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs). All raw sediment extracts induced significant Ah-agonistic effects, and the bioassay-derived 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) equivalents of raw extracts (TEQ_raws) ranged from 8.5 to 336.0 pg/g dry weight (dw). Chemical analysis-derived TEQs (TEQ_chems) ranged from 20.5 to 64.8 pg/g dw. When raw extracts were purified by sulphuric acid silica gel column to derive acid stable fraction, the TCDD equivalents in this fraction (TEQ_stables) ranged from 2.7 to 63.8 pg/g dw. PCBs, PCDDs and PCDFs contributed about 51.4-72.1%, 1.2-7.3%, and 16.4-34.8% of TEQ_stables, respectively, and the sum was 69.1-108.6%. Therefore, about 65.0% of TEQ_raws could be attributed to acid labile fraction and only 3.3-9.6% to PAHs. These observations suggested that acid stable fraction and labile fraction contributed together to total Ah-agonistic effects in the sediments, and PCBs and PCDFs might be the two main components in acid stable Ah-agonists. The proposed approach using both H4IIE cell bioassay and chemical analysis could be used for characterization and prioritization of Ah-agonists in river sediments and helpful to the following progression of ecological remediation.     

Differences between Arctic and Atlantic fjord systems on bioaccumulation of persistent organic pollutants in zooplankton from Svalbard

Differences in bioaccumulation of persistent organic pollutants (POPs) between fjords characterized by different water masses were investigated by comparing POP concentrations, patterns and bioaccumulation factors (BAFs) in seven species of zooplankton from Liefdefjorden (Arctic water mass) and Kongsfjorden (Atlantic water mass), Svalbard, Norway. No difference in concentrations and patterns of POPs was observed in seawater and POM; however higher concentrations and BAFs for certain POPs were found in species of zooplankton from Kongsfjorden. The same species were sampled in both fjords and the differences in concentrations of POPs and BAFs were most likely due to fjord specific characteristics, such as ice cover and timing of snow/glacier melt. These confounding factors make it difficult to conclude on water mass (Arctic vs. Atlantic) specific differences and further to extrapolate these results to possible climate change effects on accumulation of POPs in zooplankton. The present study suggests that zooplankton do biomagnify POPs, which is important for understanding contaminant uptake and flux in zooplankton, though consciousness regarding the method of evaluation is important.     

Concentrations in bird feathers reflect regional contamination with organic pollutants

Feathers have recently been shown to be potentially useful non-destructive biomonitoring tools for organic pollutants. However, the suitability of feathers to monitor regional variations in contamination has not been investigated until now. Here concentrations of organic pollutants were compared in feathers of common magpies (Pica pica) between urban and rural areas in Flanders, Belgium. The results showed that concentrations of p,p'-dichlorodiphenyldichloroethylene (DDE) were significantly higher in the rural areas (rural: 12-140 ng/g feather, urban: 1.1-7.2 ng/g feather), while polychlorinated biphenyls (PCBs) were significantly more available in an urban environment (sum PCBs — rural: 2.9-22 ng/g feather, urban: 41-240 ng/g feather). This pattern agrees with previous studies using other tissues than feathers as a biomonitoring tool. In addition, differences in PCBs and PBDEs profiles were found with lower halogenated congeners being more prominent in the urban areas in comparison to the rural areas. In summary, feathers seem to reflect regional variations in contamination, which strengthens their usefulness as a non-destructive biomonitor for organic pollutants.     

Combining data sets of organochlorines (OCs) in human plasma for the Russian Arctic

As part of AMAP's human circumpolar study of POPs, an international effort was initiated to extend coverage to communities across the Russian Arctic. Two additional laboratories were invited to join the analytical component of this effort, resulting in four participating analytical centres. Although quality assurance measures were put in place, and the level of performance of the laboratories was generally acceptable, deficiencies in the analytical protocols used were recognized subsequent to the collection and analyses of the plasma specimens. The current paper describes the criteria employed to critically appraise the four data bases and guide their integration into a single data set. Summary statistics are presented for plasma concentrations of major PCBs, p,p′-DDE, p,p′-DDT, β-HCH, and HCB for communities/regions across the arctic/subarctic Russian continent, and for one community located in the Aral Sea area of Uzbekistan (a control group). Highly exposed people were identified in the coastal communities of Chukotka, which appears mainly related to marine mammal intake, but recent pesticide use is also suspected. Other communities with intermediate levels of PCBs had relatively elevated β-HCH, p,p′-DDT and HCB concentrations and low DDE/DDT ratios (<10), suggesting recent pesticide use.     

Characteritization of, and health risks from, polychlorinated dibenzo-p-dioxins/dibenzofurans from incense burned in a temple

Polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) may cause adverse health effects. However, PCDD/F emissions from burning incense in temples have rarely been addressed. This study investigates PCDD/F emissions from burning incense in a temple. The mean total PCDD/F concentrations were 72.4-82.2 pg Nm^− 3 at two indoor sites; their corresponding mean total PCDD/Fs I-TEQ concentrations (0.24-0.27 pg I-TEQ Nm^− 3) were ~ 11 times that at a background location. In air samples collected from burning incense, OCDFs accounted for approximately 90% of total PCDD/Fs at the two indoor sites and an outdoor site near the temple, while the major PCDD/Fs in incense ash were PCDDs. The total PCDD/F content and toxic equivalent value of incense ash were 617 pg g^− 1 and 1.55 pg I-TEQ g^− 1, respectively. At the three sites inside/outside the temple, the air and ash samples contained the same four primary PCDD/Fs-OCDD, 1,2,3,4,6,7,8-HpCDD, OCDF and 1,2,3,4,6,7,8-HpCDF. The Cl⁻ emission factor, which is related to the PCDD/F formation, from burning incense was 0.454 mg g^− 1. The resultant lifetime average daily dose and cancer risk for temple workers were 0.00964 pg I-TEQ day^− 1 kg^− 1 and 9.64 × 10^− 6, respectively, approximately 2 times that for residents near the temple (0.00489 pg I-TEQ day^− 1 kg^− 1 and 4.89 × 10^− 6, respectively). We suggest that the chlorine content in incense must be regulated, and the high risk of PCDD/F exposure from burning incense for temple workers and visitors should be of concern.     

Congener-specific accumulation and patterns of chlorinated and brominated contaminants in adult male walruses from Svalbard, Norway: indications for individual-specific prey selection

Blubber samples from 17 adult, male walruses were sampled in eastern Svalbard and analyzed for chlorinated and brominated contaminants. A wide range of contaminants were detected, including PCBs (mean 2000; 95% range 1165-4005 ng/g lipid), DDE (mean 100: 95% range 50-310) ng/g lipid), chlordanes (mean 2500; 95% range 1347-5009) ng/g lipid, toxaphenes (mean 80; 95% range 51-132 ng/g lipid) and polybrominated diphenyl ethers (PBDEs) (mean 15 ng/g; 95% range 9-27 ng/g lipid). PCB and DDE levels were substantially lower than those of animals sampled 10 year earlier in this area, confirming a decreasing trend for these compounds in the Arctic. However, compared to other recently sampled marine mammals from Svalbard, walruses showed relatively high PCB and chlordane levels although they had lower levels of DDE, toxaphenes, and PBDEs, possibly due to species- and location-specific differences in exposure and metabolism. The range in contaminant levels found within the sample group was vast, despite the fact that the animals investigated were all adult males from the same location. The PCB pattern in highly contaminated animals was different from that in animals with low levels of contamination, with relatively more persistent PCBs in the highly contaminated group. This suggests that the more contaminated animals were feeding at higher trophic levels; possibly targeting seals in addition to mollusks as their prey. This suggestion was reinforced by the fatty acid profiles of the inner blubber layer of walruses with low versus high contaminant levels, which suggested different diets for the two groups.     

Persistent organic pollutants (POPs) in the sewage treatment plant of Thessaloniki, northern Greece: occurrence and removal

The occurrence and the removal of persistent organic pollutants (POPs) during the conventional activated sludge treatment process were investigated in the wastewater treatment plant of the city of Thessaloniki, northern Greece. POPs of interest were seven polychlorinated biphenyls (PCBs) and 19 organochlorine pesticides. Target compounds were determined at six different points across the treatment system. Most abundant compounds in raw wastewater at all treatment stages were PCB-52, PCB-110, PCB-180 and Heptachlor-exo-epoxide. Quintozene occurred frequently but in relatively low concentrations. Hexachlorocyclohexanes, DDT and its metabolites (DDE, DDD) and Aldrin, Dieldrin, Endrin, Isodrin ("Drins") were found at medium or low frequencies and in concentrations close to their detection limits. Removal percentages throughout the whole treatment process ranged from 65% to 91% for individual POP species. Significant linear relationship was observed between removal efficiency and log Kow for PCBs suggesting that compounds with a strong hydrophobic character are principally removed through sorption to sludge particles and transfer to the sludge processing systems. Total PCBs' concentrations in sewage sludge ranged between 185 and 765 ng g(-1) dw being below the EU limit for use of sludge in agriculture.     

Atmospheric monitoring of organic pollutants in the Arctic under the Arctic Monitoring and Assessment Programme (AMAP): 1993-2006

Continuous and comparable atmospheric monitoring programs to study the transport and occurrence of persistent organic pollutants (POPs) in the atmosphere of remote regions is essential to better understand the global movement of these chemicals and to evaluate the effectiveness of international control measures. Key results from four main Arctic research stations, Alert (Canada), Pallas (Finland), Storhofdi (Iceland) and Zeppelin (Svalbard/Norway), where long-term monitoring have been carried out since the early 1990s, are summarized. We have also included a discussion of main results from various Arctic satellite stations in Canada, Russia, US (Alaska) and Greenland which have been operational for shorter time periods. Using the Digital Filtration temporal trend development technique, it was found that while some POPs showed more or less consistent declines during the 1990s, this reduction is less apparent in recent years at some sites. In contrast, polybrominated diphenyl ethers (PBDEs) were still found to be increasing by 2005 at Alert with doubling times of 3.5 years in the case of deca-BDE. Levels and patterns of most POPs in Arctic air are also showing spatial variability, which is typically explained by differences in proximity to suspected key source regions and long-range atmospheric transport potentials. Furthermore, increase in worldwide usage of certain pesticides, e.g. chlorothalonil and quintozene, which are contaminated with hexachlorobenzene (HCB), may result in an increase in Arctic air concentration of HCB. The results combined also indicate that both temporal and spatial patterns of POPs in Arctic air may be affected by various processes driven by climate change, such as reduced ice cover, increasing seawater temperatures and an increase in biomass burning in boreal regions as exemplified by the data from the Zeppelin and Alert stations. Further research and continued air monitoring are needed to better understand these processes and its future impact on the Arctic environment.     

Remediation of PCB contaminated soils in the Canadian Arctic: excavation and surface PRB technology

The site BAF-5 is located on the summit of Resolution Island, Nunavut, just southeast of Baffin Island at 61 degrees 35'N and 60 degrees 40'W. The site was part of a North American military defense system established in the 1950s that became heavily contaminated with PCBs during and subsequent, its operational years. Remediation through excavation of the PCB contaminated soil at Resolution Island began in 1999 and at its completion in 2006 approximately 5 tonnes of pure PCBs in approximately 20,000 m3 of soil were remediated. Remediation strategies were based on both quantity of soil and level of contamination in the soil. Excavation removed 96% of the PCB contaminated soil on site. In 2003, a surface funnel-and-gate permeable reactive barrier was design and constructed to treat the remaining contamination left in rock crevices and inaccessible areas of the site. Excavation had destabilized contaminated soil in the area, enabling contaminant migration through erosion and runoff pathways. The barrier was designed to maximize sedimentation through settling ponds. This bulk removal enabled the treatment of highly contaminated fines and water through a permeable gate. The increased sediment loading during excavation required both modifications to the funnel and a shift to a more permeable, granular system. Granulated activated charcoal was chosen for its ability to both act as a particle retention filter and adsorptive filter. The reduction in mass of PCB and volume of soils trapped by the funnel of the barrier indicate that soils are re-stabilizing. In 2007, nonwoven geotextiles were re-introduced back into the filtration system as fine filtering could be achieved without clogging. Monitoring sites downstream indicate that the barrier system is effective. This paper describes the field progress of PCB remediation at Resolution Island.     

Hexachlorocyclohexanes (HCH) in ringed seal (Phoca hispida) from Ulukhaktok (Holman), NT: Trends from 1978 to 2006

Trends in α-, β-, and γ-hexachlorocyclohexane (HCH) concentrations were examined in blubber lipid of ringed seals (Phoca hispida) from Ulukhaktok (Holman), NT (Canada) sampled at intervals between 1978 and 2006. α-HCH usually represented approximately 90% of the total HCH isomers. α-HCH and γ-HCH concentrations showed no change over the sampling interval, but β-HCH concentrations increased significantly, about 8-10-fold in females and 4-5-fold in males. Residue concentrations showed no dependence on age. Concentrations (all data as ng/g lipid, GM (range)) of α-HCH were significantly higher (P < 0.001 by t-test) in males (217 (93.9-517), n = 37) than those in females (138 (40.9-402), n = 38). β-HCH concentrations did not differ between the sexes. Concentrations of γ-HCH were significantly higher (P < 0.05) in males (6.74 (0-46.7)) than in females (4.35 (0-19.0)). Although global emissions of both α-HCH and β-HCH have declined since the early 1980's, the “signal” of HCH emission changes has not yet resulted in a “response” in ringed seal residue concentrations. In the light of our current understanding of the dynamics of HCH in the Arctic, we conclude that any such response may not be detected by retrospective analyses of the sort describe here at least for another decade or so, because of the longevity of the seals.     

Long-term changes of mercury levels in ringed seal (Phoca hispida) from Amundsen Gulf, and beluga (Delphinapterus leucas) from the Beaufort Sea, western Canadian Arctic

Mercury (Hg) concentrations were determined in the canine teeth of ringed seals (Phoca hispida) harvested during the 13th–14th, late 19th and early 21st Centuries in Amundsen Gulf, Northwest Territories, Canada. Most historical and pre-industrial teeth contained undetectable Hg levels (i.e. < 1.0 ng/g DW), whereas samples from 2001–03 contained up to 12 ng/g DW in an age-dependent pattern. Assuming a median [Hg] value in 13th–14th Century teeth of half the detection limit (i.e. 0.5 ng/g DW), geometric means of Hg in modern teeth were 9–17 times those of seals in the 14th Century, equivalent to an anthropogenic input of 89–94% of total Hg in modern seals. These results corroborate a previous study of beluga (Delphinapterus leucas) in the nearby Beaufort Sea. While the seals' trophic position (inferred from δ¹⁵N values) did not change over time, modern δ¹³C values were lower by about 2‰ than in the 14th and 19th Centuries. This could be due to increased dissolution of anthropogenically derived CO₂ in the ocean from the atmosphere, but could also indicate more offshore pelagic feeding by modern seals, which might be a factor in their Hg exposure. New tooth [Hg] data are also presented for the Beaufort Sea beluga, using recently-discovered museum samples collected in 1960/61, which showed that most of the anthropogenic contribution to beluga Hg had already taken effect by 1960 (reaching  75% of total Hg). Taken together, the long-term seal and beluga data indicate that whereas Hg levels in the marine ecosystems of the western Canadian Arctic were probably unchanged from pre-industrial times up to the late 19th Century, there was a significant, many-fold increase in the early to mid-20th Century, but little or no change after about the early 1960s.     

A model assessment of polychlorinated dibenzo-p-dioxin and dibenzofuran sources and fate in the Baltic Sea

The contamination of the Baltic Sea with polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) has resulted in restrictions on the marketing and consumption of Baltic Sea fish, making this a priority environmental issue in the European Union. To date there is no consensus on the relative importance of different sources of PCDD/Fs to the Baltic Sea, and hence no consensus on how to address this issue. In this work we synthesized the available information to create a PCDD/F budget for the Baltic Sea, focusing on the two largest basins, the Bothnian Sea and the Baltic Proper. The non-steady state multimedia fate and transport model POPCYCLING-Baltic was employed, using recent data for PCDD/F concentrations in air and sediment as boundary conditions. The PCDD/F concentrations in water predicted by the model were in good agreement with recent measurements. The budget demonstrated that atmospheric deposition was the dominant source of PCDD/Fs to the basins as a whole. This conclusion was supported by a statistical comparison of the PCDD/F congener patterns in surface sediments from accumulation bottoms with the patterns in ambient air, bulk atmospheric deposition, and a range of potential industrial sources. Prospective model simulations indicated that the PCDD/F concentrations in the water column will continue to decrease in the coming years due to the slow response of the Baltic Sea system to falling PCDD/F inputs in the last decades, but that the decrease would be more pronounced if ambient air concentrations were to drop further in the future, for instance as a result of reduced emissions. The study illustrates the usefulness of using monitoring data and multimedia models in an integrated fashion to address complex organic contaminant issues.     

Characterization of dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the atmosphere of different workplaces of a sinter plant

This study investigated concentrations, contents and congener profiles of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the workplaces of a sintering plant. Air samples were collected from the charging zone, the sintering zones of the sintering grate and the rough roll shredder, and the control room. The charging zone was found to have a higher total suspended particulate (TSP) but lower PCDD/F concentrations (=4969 microg nm(-3) and 7.61 pg nm(-3), respectively) than the sintering zone (=1422-1448 microg nm(-3) and 19.16-23.17 pg nm(-3), respectively). The TSP and PCDD/F concentrations were lowest in the control room (=98 microg nm(-3) and 1.75 pg nm(-3), respectively). However, the above concentrations were within the range of a typical urban-industrial area. Quite similar PCDD/F contents were found in particles in the sintering zones and control room (=11.72-14.30 and 15.85 ng g(-1), respectively) suggesting that the sintering zone and the control room are very similar. In both charging and sintering zones, 2,3,4,7,8-PeCDF contributed 40-60% to the total I-TEQ in both the gas phase and particle phase. However, in control room, both congeners 2,3,4,7,8-PeCDF and 2,3,7,8-TCDD were the main contributors; the later contributed 30% of the total I-TEQ in gas phase. In control room, the contribution of 2,3,7,8-TCDD to the total PCDD/F concentration in the gas phase greatly exceeded that in particle phase (=5.5% and 0.8%, respectively). Therefore, solutions must be sought to avoid the transfer of not only the particle-phase but also the gas-phase PCDD/Fs from the sintering zone to the control room in the future.     

Characterization of polychlorinated dibenzo-p-dioxin/dibenzofuran emissions from joss paper burned in a furnace with air pollution control devices

Burning joss paper, a common practice in temples in some Asian countries, can release toxic pollutants. This study investigated polychlorinated dibenzo-p-dioxin/dibenzofuran (PCDD/F) emissions and profiles from burning joss paper in a temple furnace connected to two wet scrubbers. The mean total PCDD/F content and corresponding toxic equivalent quantity (TEQ) in joss paper were 193 ng kg^− 1 and 0.645 ng I-TEQ kg^− 1, respectively, whereas those in bottom ash from burned joss paper were 18.5 ng kg^− 1 and 1.92 ng I-TEQ kg^− 1, respectively. The wet scrubbers decreased individual PCDD/F emissions by 26.7-71.0% and those of total PCDD/Fs and I-TEQ by 47.2% and 66.0%, respectively. The total PCDD/F TEQ emission factors before and after the wet scrubbers were 8.14 and 3.42 µg I-TEQ ton-feedstock^− 1, respectively. The estimated total PCDD/F and corresponding TEQ emissions were 5.29 g year^− 1 and 0.462 g I-TEQ year^− 1, respectively, in Taiwan. Burning joss paper in temple furnaces is a significant source of PCDD/F emissions.     

Levels of brominated flame retardants and other pesistent organic pollutants in breast milk samples from Limpopo Province, South Africa

The non-occupational exposure to brominated flame retardants, and other persistent organic pollutants (POPs) was studied by collecting human breast milk samples from mothers residing in Thohoyandou area, a rural district in the Limpopo Province, northern part of South Africa (SA). Of all collected samples to be analysed (n = 28), those with large enough milk volumes, (n = 14) were quantified for polybrominated diphenyl ethers (PBDEs) (9 congeners: BDE-28, 47, 66, 99, 100, 138, 153, 154, and 183) and hexabromocyclododecane (HBCD) on a GC equipped with dual capillary columns and dual electron-capture detectors (ECD). The levels of PBDE congeners (median sumBDE 1.3 ng/g of lipids) and of HBCD were not far from levels generally found in European studies, and this study may be the first report on the presence of PBDEs and HBCD in SA breast milk. On a congener basis, the finding of comparably high BDE-183 levels suggests a specific PBDE usage, or contamination situation in SA. Apart from BFRs, the high DDT levels found in the breast milk from this area (median and maximum sumDDT levels of about 4 600 and over 20 000 ng/g of lipids, respectively; n = 28) have earlier been reported. In addition, other POPs (PCBs, HCB and HCHs) were found in SA breast milk, at relatively low levels. To conclude, measurable levels of PBDEs and HBCD, and a specific BDE congener pattern, were found in breast milk from the Limpopo province, SA. A number of other POPs, including DDTs in high levels, were also present.     

Persistent organic pollutants in edible marine species from the Gulf of Naples, Southern Italy

Edible tissues from 10 marine species, collected from the Gulf of Naples in the Southern Tyrrhenian Sea (Italy) between February and July 2003, were analysed for the presence of organochlorine pesticides hexachlorobenzene (HCB) and DDTs (p,p'-DDT, p,p'-DDE, and p,p'-DDD), and 20 polychlorinated biphenyls (PCBs). The PCB levels (calculated as the sum of all the determined congeners) were found to be the highest (from 56.8 to 47909.5 ng/g on lipid basis), followed by the DDTs (sum of p,p'-DDT and its metabolites; 相似文献   

Persistent organic pollutants in outmigrant juvenile chinook salmon from the Lower Columbia Estuary, USA

Although chemical contaminants are recognized as a potential factor contributing to the salmon declines in the Pacific Northwest, United States, information on contaminant concentrations in threatened and endangered salmon from the Columbia Estuary is limited. In this study we monitored exposure to several persistent organic pollutants [polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethanes (DDTs) and other organochlorine pesticides] in outmigrant juvenile fall chinook salmon (Oncorhynchus tschawytscha) in the Lower Columbia River, and evaluated the potential for adverse effects on salmon and the estuarine food web. Contaminants were measured in whole bodies and stomach contents of subyearling to yearling chinook collected in 2001 and 2002 from sites near the confluence of the Columbia and Willamette Rivers, Longview, and within the lower Estuary. The contaminants detected at highest concentrations in salmon whole bodies were PCBs and DDTs. Average concentrations of PCBs in salmon from the sampling sites ranged from 1300 to 14,000 ng/g lipid, in some cases exceeding the recently estimated threshold for adverse health effects in juvenile salmonids of 2400 ng/g lipid. Average DDT concentrations ranged from 1800 to 27,000 ng/g lipid. These levels are among the highest measured in juvenile salmon from Pacific Northwest estuaries to date. Concentrations of PCBs and DDTs in salmon whole bodies showed no clear spatial gradient from the Willamette/Columbia Confluence to the mouth of the Columbia, but tended to be higher in larger fish and older fish, suggesting a correlation with estuarine residence time. PCBs, DDTs, and PAHs were all found in salmon stomach contents, indicating that prey is a source of exposure. Hatchery feed may have contributed to contaminant body burdens in those fish that were of hatchery origin. Contaminant body burdens in salmon were poorly correlated with contaminant concentrations previously measured in local bed sediments, suggesting that pelagic as well as benthic sources are important in determining salmon exposure.