Typical dioxin concentrations in agriculture soils of Washington state and potential sources

Background or typical levels of polychlorinated dibenzo-p-dioxins and of polychlorinated dibenzo-p-furans in soils have become increasingly important in the regulatory community, as dioxins have come under increased scrutiny due to their toxicity and persistence. Knowing the typical levels of dioxin in soils is important to set regulatory levels, to prevent further contamination, and for setting cleanup levels. A random sample (n=54) of agricultural lands within Washington state revealed a typical concentration of "dioxin" of 0.14 ng/kg (toxicity equivalents, TEQ). For a comparison, residential urban areas, forested, and open areas were also investigated on a smaller scale (n=14, 8, and 8, respectively) with typical dioxin values of 4.1, 2.3, and 1.0 ng/kg (TEQs), respectively. A discriminant function analysis was used to examine soil dioxin profiles and associations with potential known dioxin sources in Washington state. Soil sample dioxin profiles could not be discriminated from those of biosolids and pentachlorophenol products.     

Aircraft measurements of nitrogen and phosphorus in and around the Lake Tahoe Basin: implications for possible sources of atmospheric pollutants to Lake Tahoe

Atmospheric deposition of nitrogen (N) and phosphorus (P) into Lake Tahoe appears to have been a major factor responsible for the shifting of the lake's nutrient response from N-limited to P-limited. To characterize atmospheric N and P in and around the Lake Tahoe Basin during summer, samples were collected using an instrumented aircraft flown over three locations: the Sierra Nevada foothills east of Sacramento ("low-Sierra"), further east and higher in the Sierra ("mid-Sierra"), and in the Tahoe Basin. Measurements were also made within the smoke plume downwind of an intense forest fire just outside the Tahoe Basin. Samples were collected using a denuder-filter pack sampling system (DFP) and analyzed for gaseous and water-soluble particle components including HNO3/ NO3-, NH3 /NH4+, organic N (ON), total N, SRP (soluble reactive phosphate) and total P. The average total gaseous and particulate N concentrations (+/- 1sigma) measured over the low- and mid-Sierra were 660 (+/- 270) and 630 (+/- 350) nmol N/m3-air, respectively. Total airborne N concentrations in the Tahoe samples were one-half to one-fifth of these values. The forest fire plume had the highest concentration of atmospheric N (860 nmol N/m3-air) and a greater contribution of organic N (ON) to the total N compared to nonsmoky conditions. Airborne P was rarely observed over the low- and mid-Sierra but was present at low concentrations over Lake Tahoe, with average +/- 1sigma) concentrations of 2.3 +/- 2.9 and 2.8 +/- 0.8 nmol P/m3-air under typical clear air and slightly smoky air conditions, respectively. Phosphorus in the forestfire plume was present at concentrations approximately 10 times greater than over the Tahoe Basin. P in these samples included both fine and coarse particulate phosphate as well as unidentified, possibly organic, gaseous P species. Overall, our results suggest that out-of-basin emissions could be significant sources of nitrogen to Lake Tahoe during the summer and that forest fires could be important sources of both N and P.     

Locating sources of surf zone pollution: a mass budget analysis of fecal indicator bacteria at Huntington Beach, California

The surf zone is the unique environment where ocean meets land and a place of critical ecological, economic, and recreational importance. In the United States, this natural resource is increasingly off-limits to the public due to elevated concentrations of fecal indicator bacteria and other contaminants, the sources of which are often unknown. In this paper, we describe an approach for calculating mass budgets of pollutants in the surf zone from shoreline monitoring data. The analysis reveals that fecal indicator bacteria pollution in the surf zone at several contiguous beaches in Orange County, California, originates from well-defined locations along the shore, including the tidal outlets of the Santa Ana River and Talbert Marsh. Fecal pollution flows into the ocean from the Santa Ana River and Talbert Marsh outlets during ebb tides and from there is transported parallel to the shoreline by wave-driven surf zone currents and/or offshore tidal currents, frequently contaminating >5 km of the surf zone. The methodology developed here for locating and quantifying sources of surf zone pollution should be applicable to a wide array of contaminants and coastal settings.     

Cost effectiveness of reducing dioxin emissions from municipal solid waste incinerators in Japan

The main sources of dioxin emissions are municipal solid waste incinerators. The Japanese national government has set an emission standard for dioxins to reduce dioxin exposure levels. In this study, cost-effectiveness analyses are carried out regarding countermeasures that were recently taken and are being taken at municipal solid waste incinerators in Japan. Annual costs were estimated by telephone survey and model calculations. Annual decrease in the incidence of cancer was estimated in three steps. First, the annual decrease in the volume of dioxin emissions was estimated. Next, using a mathematical model, the annual decrease in human exposure was estimated. Finally, the annual decrease in the incidence of cancer was estimated by applying the cancer slope factor. When annual costs are divided by the annual number of life-years saved, cost per life-year saved (CPLYS) was obtained. CPLYS was estimated to be 7.9 million yen for emergency countermeasures and 150 million yen for long-term countermeasures. However, it must be noted that these obtained CPLYSs are highly dependent on the cancer slope factor and should be considered as an upper limit since there may be a cancer effect threshold.     

Analysis of sources of dioxin contamination in sediments and soils using multivariate statistical methods and neural networks

Multivariate statistical methods and neuronal networks were used to evaluate the concentration dioxin patterns of a large data set (407 samples) in order to identify the dioxin sources of contaminated waters (sediment and suspended particulate matter samples). The evaluations indicated that a considerable proportion of the dioxin contamination of the river Elbe in the section between the Mulde tributary and the North Sea and their flood plains (soil samples) and the Port of Hamburg was caused by pollution originating from the Bitterfeld region, an industrial area of the former German Democratic Republic. The dioxin patterns of sediment samples from tributaries of the river Elbe in the Bitterfeld area itself are similar to dioxin patterns that can be attributed to metalworking processes. The dioxin patterns of the Hamburg inner city waters could be attributed to "incineration" dioxin sources, for example waste incineration plants. The results of cluster analysis applying different modes of distance measure and linkage compared well with neuronal networks. The number of clusters was determined based on the stability of the results of different cluster analyses and background information.     

Occurrence and sources of perfluorinated surfactants in rivers in Japan

We analyzed perfluorinated surfactants (PFSs) in 20 river samples and 5 wastewater secondary effluent samples in Japan to reveal their occurrence and sources. Nine PFS species were determined: perfluorooctanesulfonate (PFOS), perfluorooctane sulfonamide (FOSA), perfluoroheptanoate (PFHpA), perfluorooctanoate (PFOA), perfluorononanoate (PFNA), perfluorodecanoate (PFDA), perfluoroundecanoate (PFUA), perfluorododecanoate (PFDDA), and perfluorotridecanoate (PFTDA). PFSs were detected in all rivers, revealing nationwide contamination of rivers. In particular, 11 out of 20 river samples exceeded New Jersey guidance for PFOA in drinking water (40 ng/L). PFOS, PFHpA, PFOA, and PFNA were major species in Japan. Concentrations of PFOS, PFHpA, and PFNA in rivers were strongly correlated with population density, suggesting that the chemicals were derived from urban activities. PFOA showed a significant but weak correlation. We used crotamiton, a marker of sewage effluent, for further source analysis. Concentrations of PFOS, PFHpA, and PFNAwere strongly correlated with those of crotamiton, and plots of secondary effluents fell near the regression lines of rivers, indicating that the PFOS, PFHpA, and PFNA in rivers were derived from sewage effluent. On the other hand, PFOA was found at remarkably high levels (54-192 ng/L) in seven river samples containing low levels of crotamiton, suggesting that it was derived from nonsewage point sources, as well as sewage effluent. The total fluxes of sewage-derived PFOS, PFHpA, PFOA, and PFNA from Japan were estimated to be 3.6, 2.6, 5.6, and 2.6 t/year, respectively. This is the first report to identify PFOA in several rivers, derived from nonsewage point sources, by using a marker of sewage effluent.     

食品重金属污染来源的研究进展

食品重金属污染严重危害食品安全。文中结合国内外研究现状,从食品原材料、食品加工制作、食品贮藏销售3个方面综述了食品重金属污染的来源,以期为探寻当前食品重金属残留的产生因素,并制订具体的防控措施提供参考。     

Identifying sources of nitrogen to Hanalei Bay, Kauai, utilizing the nitrogen isotope signature of macroalgae

Sewage effluent, storm runoff, discharge from polluted rivers, and inputs of groundwater have all been suggested as potential sources of land derived nutrients into Hanalei Bay, Kauai. We determined the nitrogen isotopic signatures (delta(15)N) of different nitrate sources to Hanalei Bay along with the isotopic signature recorded by 11 species of macroalgal collected in the Bay. The macroalgae integrate the isotopic signatures of the nitrate sources over time, thus these data along with the nitrate to dissolved inorganic phosphate molar ratios (N:P) of the macroalgae were used to determine the major nitrate source to the bay ecosystem and which of the macro-nutrients is limiting algae growth, respectively. Relatively low delta(15)N values (average -0.5% per hundred) were observed in all algae collected throughout the Bay; implicating fertilizer, rather than domestic sewage, as an important external source of nitrogen to the coastal water around Hanalei. The N:P ratio in the algae compared to the ratio in the Bay waters imply that the Hanalei Bay coastal ecosystem is nitrogen limited and thus, increased nitrogen input may potentially impact this coastal ecosystem and specifically the coral reefs in the Bay. Identifying the major source of nutrient loading to the Bay is important for risk assessment and potential remediation plans.     

Identifying sources and biomagnification of persistent organic contaminants in biota from mountain streams of southwestern British Columbia, Canada

We assessed whether biota occupying mountain streams accumulate and biomagnify remotely derived organic pollutants originating from atmospheric inputs to snowpack and glacial runoff and from marine sources introduced by migrating anadromous salmon. Several persistent organic pollutants including polychlorinated biphenyls (PCBs), p,p'-dichloro-diphenyl-dichloroethylene, hexachlorobenzene, and trans-nonachlor were commonly detected in benthic invertebrates, salmon fry (Oncorhynchus spp.), and eggs of an aquatic passerine, the American dipper (Cinclus mexicanus) from the Chilliwack River watershed, British Columbia, Canada. Total PCBs and several organochlorines (OCs) biomagnified from benthic invertebrate composites to salmon fry to dipper eggs. Invertebrate samples generally did not differ significantly in contaminant burdens between the river main stem where salmon are more abundant and higher-elevation tributaries where the salmon density is lower. Concentrations of total OCs and total PCBs in dipper eggs were positively related to drainage basin area and collection year but not to elevation. No differences in PCB congener patterns existed between dipper egg samples from the Chilliwack watershed and other watersheds in southwestern British Columbia. However, principal component analysis revealed significant spatial differences in egg PCB congener patterns between the main Chilliwack River and the higher-elevation tributaries. This difference was primarily due to a greater occurrence of lower chlorinated PCB congeners (66 and 105) in dipper eggs collected from the tributaries and higher loadings of the more stable and persistent congeners (153, 138, 130, and 128) in eggs from the river main stem. The results suggest that atmospheric sources are the main contributor of contaminants detected in biota from the region and that biomagnification is a common pathway for accumulation in lotic predators such as the American dipper.     

On-farm sources of microbial contamination of persimmon fruit in Japan

Potential sources of microbial contamination for persimmon fruit during growing and harvesting in the 2005 season were investigated to provide a baseline to design the good agricultural practices program for persimmons in Japan. Microbial counts in the peel of persimmon fruit during production season were close to or below 2.4 log CFU/g for bacteria and 3.0 log CFU/g for fungi but were above these values on harvested fruit. The counts in the flesh were below the detection level with all fruit. Bacteria and molds isolated from peel and flesh of persimmons during growing were phytopathogenic and soilborne organisms such as bacteria genera Enterobacter and Bacillus and mold genera Fusarium and Cladosporium, which were found in soil, weeds, agricultural water, and pesticide solution throughout the production season. The agricultural water was one of the most important potential preharvest sources, because Escherichia coli O157:H7 was identified from agricultural water in May, and Salmonella was detected in agricultural water, pesticide solution containing the agricultural water for the mixture, and soil after application of the pesticide solution in June. Neither of the two pathogenic bacteria was detected in any of the fruit samples. Microbial counts and diversity in the peel of persimmons at harvest increased after contact with plastic harvest basket and container, which could be sources of contamination during harvesting. Therefore, monitoring and management on-farm should focus on agricultural water and harvest equipment as important control points to reduce microbial contamination on persimmons.     

Relationship between environmental pollution in Manzala Lake and health profile of fishermen

Manzala Lake exposed to many pollultants including untreated sewage, agricultural and industrial wastes which increase the concentration of heavy metals, and compromize the health state of the fishermen. This study investigated 100 fishermen and 100 males of other occupations as controls. Both groups work in and live on and around the lake. Clinical examination revealed no significant changes between the fishermen and control group as regards the cardiovascular, gastrointestina and dermatological systems. However, the urinary, musculo-skeletal and respiratory symptoms were significantly higher in fishermen than in control males. There was a significant decrease in neutrophils (48.8%) and a significant increase in lymphocytes and eosinophils (35.4% and 9%), respectively. Hepatotoxicity was evidenced by an increase in serum aspartate transaminase and alanine transaminase. There were no significant differences in serum creatinine and urea between fishermen and control. Levels of lead, cadmium and mercury in water and sediment were 0.26, 0.014, 0.002 mg/l, and 33.5, 1.37, 0.28 lg/kg, respectively. Levels of the three heavy metals in the fish samples and serum of fishermen and control males in average were 1.06, 0.18, 0.00025 ppm, 523, 33.5, 13.7 lg/l and 374, 12.8, 11.2 lg/l, respectively. This study aimed to establish the relation between the environmental pollution and the health status of the popu-lation inhabiting the contaminated areas.     

Levels and toxicokinetic behaviors of PCDD, PCDF, and coplanar PCB congeners in common cormorants from Lake Biwa, Japan

Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (Co-PCBs) were determined in the liver and pectoral muscle of common cormorants (Phalacrocorax carbo) collected from Lake Biwa, Japan. To clarify the toxicokinetic behaviors and potential toxicities of these chemicals, the present study addresses life-stage- and tissue-specific accumulation of the congeners. Total 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents (TEQs) were in the range of 360 to 50,000 pg/g lipid weight in the liver and 310 to 12,000 pg/g lipid weight in the pectoral muscle. Among congeners, for which toxic equivalency factors were assigned, PCB126, 2,3,4,7,8-P5CDF, and 1,2,3,7,8-P5CDD made a greater contribution to total TEQs in the liver. Hepatic concentrations of T4- to H6CDDs, P5- and H6CDFs, and Co-PCBs (except PCB77) significantly increased with growth of cormorants, leading to life-stage-related compositional changes. The concentration ratios of liver to pectoral muscle revealed preferential accumulation of higher chlorinated congeners in hepatic tissue. For most congeners, concentration ratios significantly increased with an increase in hepatic total TEQs, suggesting their concentration-dependent hepatic sequestration. These results imply the presence of hepatic binding protein(s) such as cytochrome P450, inducible by these chemicals, which mayfunction as a binding species different from aryl hydrocarbon receptor. On the basis of these results, we conclude that the toxicokinetic behavior of each congener is life-stage-, tissue-, and concentration-dependent. TEQs in wildlife populations exposed to multiple congeners with varying concentrations should be used with caution for risk assessment, even within a species.     

食品中烷基酚类物质污染现状、来源及其检测技术研究进展

烷基酚聚氧乙烯醚(APEO)是一类由烷基酚(AP)和环氧乙烷反应合成的化合物,因其具有优良的表面活性,广泛应用于农药、包装材料、乳化剂和洗涤剂等产品中。环境中长链的APEO会降解为AP、短链APnEO(n≤2)等代谢物,这些产物会在生物体内累积,并对生物体产生雌激素效应等毒效应。目前,在许多国家和地区的人体血液、尿液、脂肪和母乳等中都检出了AP和短链APEO,而膳食摄入可能是人体暴露AP、APEO的主要途径,因此,有必要对食品中AP、APEO展开进一步研究。文中梳理了国内外食品中AP、APEO的污染现状及其来源,并综述了食品中AP、APEO的提取及检测技术。     

应用PCR-DGGE对巴氏消毒乳中腐败细菌的污染溯源研究

运用PCR-DGGE技术分析了巴氏杀菌乳从原料乳到杀菌、灌装这两个加工关键控制点的微生物动态变化和差异性,容易发生污染的环节是挤乳环节、杀菌后的加工管道和包装环节。原料乳中易携带的细菌是乳酸链球菌（Lactococcus lactis subsp.）和乳酸杆菌（Lactobacillus sp.）;挤乳环节中易受无乳链球菌（Streptococcus agalactiae）污染;杀菌后的加工管道易受热杀环丝菌（Brochothrix thermosphacta）、钻黄肠球菌（Enterococcus casseliflavus）、瑞士乳杆菌（Lactobacillus helveticus）和2株非培养的假单胞菌属（Uncultured Pseudomonas sp.）污染;肉杆菌属（Carnobacterium sp.）和产乳酸菌素的肉杆菌（Carnobacterium maltaromaticum）则在挤乳环节、杀菌后的加工管道或包装环节都可能被污染。      

Hypothesis-driven approach for the identification of fecal pollution sources in water resources

Water resource management must strive to link catchment information with water quality monitoring. The present study attempted this for the field of microbial fecal source tracking (MST). A fecal pollution source profile based on catchment data (e.g., prevalence of fecal sources) was used to formulate a hypothesis about the dominant sources of pollution in an Austrian mountainous karst spring catchment. This allowed a statistical definition of methodical requirements necessary for an informed choice of MST methods. The hypothesis was tested in a 17-month investigation of spring water quality. The study followed a nested sampling design in order to cover the hydrological and pollution dynamics of the spring and to assess effects such as differential persistence between parameters. Genetic markers for the potential fecal sources as well as microbiological, hydrological, and chemo-physical parameters were measured. The hypothesis that ruminant animals were the dominant sources of fecal pollution in the catchment was clearly confirmed. It was also shown that the concentration of ruminant markers in feces was equally distributed in different ruminant source groups. The developed approach provides a tool for careful decision-making in MST study design and might be applied on various types of catchments and pollution situations.     

全国及重点地区印染行业污染源排放数据对比

印染行业污染源排放情况存在多套统计数据。通过对比排污许可、总量控制、环境统计等各口径印染行业排放数据,分析印染行业污染源统计过程中存在的口径不对应、企业不匹配等问题。结果表明:目前印染行业的污染物排放数据尚不足以支撑环境管理工作,依然存在排污许可证缺乏水量管控、排污许可证排放量数据管理难以满足其他污染源政策管理需求、多套数据不统一影响"十四五"总量控制基数确定等问题,并指出已发证企业的证后管理及大规模数据校核迫在眉睫。