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1.
The study demonstrated that the mature dates we investigated were considered safe for human consumption. However, our findings revealed that much of the early fruit and leaves, which appeared at the advent of the fruiting season, possessed elevated levels of cadmium (Cd) that could accumulate in the food chain and thus impact adversely on the environment. In addition, animal feed for livestock contains date leaves, which should be restricted to the mature ones. The monitoring of cadmium in date palms is of considerable interest to environmental science and the thrust of this work, therefore, involved measurement, by ICP, of Cd in dates and corresponding leaf specimens, and evaluation of its distribution during the developmental stages of the fruiting season. Thirty-six date samples and 36 leaf specimens of the Fard cultivar were collected from "on" and "off" date palms during the Kimri, Bisir and Rutab stages of the fruiting season and subjected to suitable digestion procedures. Sample masses of typically 1 g (dry weight) were prepared in 25 ml dilute acid solution and investigated for trace levels of Cd by ICP-AES. Special attention was paid to contamination and the validation of our methodology. The Cd "threshold" in our study was 50 ng/g, in keeping with the levels of tolerance appearing in the literature. For the dates we found elevated levels of Cd [> 50 ng/g] in most of the samples, for both categories of "on" and "off" trees, during the Kimri stage. In the case of the leaves, the "on" samples revealed significant values up to 125 ng/g in Bisir, in some cases, but the trend for the "off" trees remained the same with the highest levels [> 100 ng/g] recorded during Kimri. Safe levels were attained during Rutab for all specimens. The possibility of a connection between Cd toxicity and the alternate-bearing phenomenon is discussed and this could be the subject of future interest.  相似文献   

2.
Three hundred samples of Mytilus galloprovincialis were collected from five stations (north, south, east, west and centre) of Lake Faro to evaluate the concentrations of organochlorine compounds and heavy metals. Quantitative determinations of organochlorine pesticides and PCBs were made by GC-ECD and confirmed with GC-MS. Concentrations of "essential" (Cu, Se and Zn) and "toxic" (As, Cd, Hg and Pb) metals were determined by an atomic absorption spectrophotometer. The results obtained show the low residue levels of p,p'-DDE in six samples of M. galloprovincialis from southern (7.00-11.00 ng/g w.w. and 148.3-275 ng/g l.w.) and western (7.60-15.37 ng/g w.w. and 126.7-256.2 ng/g l.w.) areas of Lake Faro. No appreciable residues of PCBs were found in any of the samples examined. Zn concentrations (range 11.0-18.5 microg/g w.w.) were higher than Cu (range 188.3-396.0 ng/g w.w.) and Se (range 93.5-288.9 ng/g w.w.) in all areas of origin. Cd (range 41.9-63.8 ng/g w.w.), Pb (range 64.8-93.0 ng/g w.w.) and Hg levels (range 5.7-13.1 ng/g w.w.) showed lower concentrations than permitted MRLs. The As levels were below detection limits for the all mussel samples. In conclusion, the absence of PCBs, the low levels of p,p'-DDE, the concentrations of Cd, Hg and Pb below permitted MRLs in M. galloprovincialis, used as a "biological indicator", show that Lake Faro is not at contamination risk from these contaminants and moreover is free from health problems for the consumer of mussel products.  相似文献   

3.
Pentachlorophenol (PCP) was investigated in freshwater sediments and human breast milk collected from the Pearl River Delta, China. The average level of PCP in river sediments was 7.93 ng/g based on dry weight, ranging from 1.44 to 34.4 ng/g. As to the sediments from fishponds, samples from Zhongshan had the highest PCP levels (37.5 ng/g on average), followed by Dongguan (21.1 ng/g on average) and the least in Shenzhen (3.69 ng/g on average) and Shunde (2.20 ng/g on average). Negative relationship was obtained between the PCP level and pH value in sediment (r=0.553, n=13, p<0.05), while positive relationship was found between the PCP levels and the total organic matter (TOM) levels in sediment (r=0.700, n=17, p<0.01). These results indicated that pH and TOM played important roles during the process of PCP settling down to the sediment. PCP was also detected in human breast milk with an average of 2.15 ng/g. The PCP concentration increased with the age increasing of donors. The estimated PCP body burden for mother, daily and yearly PCP intake of infants ranged from 0.16 to 4.17 mg/person, from 0.26 to 10.23 mug/infant.day and from 0.09 to 3.73 mg/infant.year, respectively.  相似文献   

4.
As polybrominated diphenyl ethers (PBDEs) face increasing restrictions worldwide, several alternate flame retardants are expected to see increased use as replacement compounds in consumer products. Chemical analysis of biosolids collected from wastewater treatment plants (WWTPs) can help determine whether these flame retardants are migrating from the indoor environment to the outdoor environment, where little is known about their ultimate fate and effects. The objective of this study was to measure concentrations of a suite of flame retardants, and the antimicrobial compound triclosan, in opportunistic samples of municipal biosolids and the domestic sludge Standard Reference Material (SRM) 2781. Grab samples of biosolids were collected from two WWTPs in North Carolina and two in California. Biosolids samples were also obtained during three subsequent collection events at one of the North Carolina WWTPs to evaluate fluctuations in contaminant levels within a given facility over a period of three years. The biosolids and SRM 2781 were analyzed for PBDEs, hexabromobenzene (HBB), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), 2-ethylhexyl 2,3,4,5-tetrabromobenzoate (TBB), di(2-ethylhexyl)-2,3,4,5-tetrabromophthalate (TBPH), the chlorinated flame retardant Dechlorane Plus (syn- and anti-isomers), and the antimicrobial agent 5-chloro-2-(2,4-dichlorophenoxy)phenol (triclosan). PBDEs were detected in every sample analyzed, and ΣPBDE concentrations ranged from 1750 to 6358 ng/g dry weight. Additionally, the PBDE replacement chemicals TBB and TBPH were detected at concentrations ranging from 120 to 3749 ng/g dry weight and from 206 to 1631 ng/g dry weight, respectively. Triclosan concentrations ranged from 490 to 13,866 ng/g dry weight. The detection of these contaminants of emerging concern in biosolids suggests that these chemicals have the potential to migrate out of consumer products and enter the outdoor environment.  相似文献   

5.
Surface sediment samples were collected from various locations in the Mumbai and Kochi harbours, west coast of India, to assess the presence of butyltin compounds. Tributyltin (TBT) and dibutyltin (DBT) varied from 16 to 16,816 ng/g dry wt. and from undetected to 469 ng/g dry wt., respectively, of the sediment in Kochi harbour. In Mumbai harbour, the values of TBT and DBT ranged between 4.5 and 1193 ng/g dry wt. and from undetected to 131 ng/g dry wt. of the sediments, respectively. The concentrations of both TBT and DBT showed strong seasonal variation probably due to the effect of tides and currents. Nevertheless, the levels of butyltin compounds were generally higher at sites influenced by shipping activities such as navigation, dry dock and ship-building activities. The presence of DBT indicates the abiotic or microbiological degradation of TBT. Compared to TBT, DBT was relatively less abundant, suggesting either fresh inputs of TBT and/or less degradation of TBT. The concentrations of TBT showed significant positive relationships with organic carbon and lipid, implying that both lipophilic and ionic interactions were probably involved in controlling the abundance of TBT at these sediments. The observed levels of butyltin compounds are much higher than those required to induce toxic effects on marine organisms, suggesting that these sediments were contaminated with butyltin compounds.  相似文献   

6.
Phthalates have long been used as plasticizers to soften plastic products and, thus, are ubiquitous in modern life. As part of the Bavarian Monitoring of Breast Milk (BAMBI), we aimed to characterize the exposure of infants to phthalates in Germany. Overall, 15 phthalates, including di-2-ethylhexyl phthalate (DEHP), di-n-butyl phthalate (DnBP), di-isobutyl phthalate (DiBP), di-isononyl phthalate (DiNP), three primary metabolites of DEHP [mono-(2-ethylhexyl) phthalate (MEHP), mono-isobutyl phthalate (MiBP), and mono-n-butyl phthalate (MnBP)], and two secondary metabolites of DEHP were analyzed in 78 breast milk samples. We found median concentrations of 3.9 ng/g for DEHP, 0.8 ng/g for DnBP, and 1.2 ng/g for DiBP, while other parent phthalates were found in only some or none of the samples at levels above the limit of quantitation. In infant formula (n=4) we observed mean values of 19.7 ng/g (DEHP), 3.8 ng/g (DnBP), and 3.6 ng/g (DiBP). For MEHP, MiBP, and MnBP, the median values in breast milk were 2.3 μg/l, 11.8 μg/l, and 2.1 μg/l, respectively. The secondary metabolites were not detected in any samples. Using median and 95th percentile values, we estimated an "average" and "high" daily intake for an exclusively breast-fed infant of 0.6 μg/kg body weight (b.w.) and 2.1 μg/kg b.w., respectively, for DEHP, 0.1 μg/kg b.w. and 0.5 μg/kg b.w. for DnBP, and 0.2 μg/kg b.w. and 0.7 μg/kg b.w. for DiBP. For DiNP, intake values were 3.2 μg/kg b.w. and 6.4 μg/kg b.w., respectively, if all values in milk were set half of the detection limit or the detection limit. The above-mentioned "average" and "high" intake values corresponded to only about 2% to 7%, respectively, of the recommended tolerable daily intake. Thus, it is not likely that an infant's exposure to phthalates from breast milk poses any significant health risk. Nevertheless, other sources of phthalates in this vulnerable phase have to be considered. Moreover, it should be noted that for infants nourished with formula, phthalate intake is of the same magnitude or slightly higher (DEHP) than for exclusively breast-fed infants.  相似文献   

7.
Two major antifouling biocides used worldwide, Irgarol 1051 and diuron, and their degradation products in Shoreham Harbour and Brighton Marina, UK were studied during 2003-2004. The highest concentrations of Irgarol 1051 were 136 and 102 ng L(-1) in water and 40 and 49 ng g(-1) dry weight in sediments for Shoreham Harbour and Brighton Marina, respectively. As the degradation product of Irgarol 1051, M1 was also widespread, with the highest concentration of 59 ng L(-1) in water and 23 ng g(-1) in sediments in Shoreham Harbour, and 37 ng L(-1) in water and 5.6 ng g(-1) in sediments in Brighton Marina. The target compounds showed enhanced concentrations during the boating season (May-July), when boats were being re-painted (January-February), and where the density of pleasure crafts was high. Overall, the concentration of Irgarol 1051 decreased significantly from late 2000 to early 2004, indicating the effectiveness of controlling its concentrations in the marine environment following restricted use. Diuron was only detected in 14% of water samples, and mostly absent from sediment samples.  相似文献   

8.
武汉月湖和莲花湖表层沉积物中持久性有机物的污染状况   总被引:1,自引:0,他引:1  
采用气-质联用技术分析了武汉汉阳月湖和莲花湖的4个表层沉积物样品中的有机污染物,探讨了两湖沉积物受持久性有机物污染的程度。月湖中共检测出124种有机物,其中属环境优先控制污染物和美国EPA筛选的内分泌干扰物19种;莲花湖中共检测出186种有机物,环境优先控制污染物和美国EPA筛选的内分泌干扰物34种。主要污染物包括:酞酸酯、酯类、酚类、杂环和苯及其衍生物等。污染物浓度顺序为L1>L2>Y2>Y1,莲花湖中有机物浓度明显高于月湖。两湖邻苯二甲酸酯的含量最高,占了污染物总量的96%~98%,邻苯二甲酸乙基己基酯(平均值 17 59903 ng/g 干重)和邻苯二甲酸二丁酯(平均值 2 515.76 ng/g 干重)是两湖沉积物中的主要酞酸酯类污染物。  相似文献   

9.
In this paper, the authors describe a sensitive method for low-level non-exchangeable OBT determination. This methodology combines suitable sample treatment, a combustion apparatus for large-sized samples and low-background liquid scintillation spectrometry, along with precautions that substantially reduce the risks of sample contamination. Great care must be taken in the measurement of non-exchangeable OBT at environmental levels. Many authors have discussed the opportunities for cross-contamination between samples and contamination by exchange with the laboratory atmosphere. The authors also describe an application of the methodology to a large-scale sampling and measurement campaign, aimed at the determination of the environmental non-exchangeable OBT background level in tree leaves and ferns collected on the site and in the vicinity of a research centre located in the south-west of France, not far from Bordeaux. This study constitutes a "zero level" for the non-exchangeable OBT activity, as, to our knowledge, there is no tritium source within or in the surroundings of the sampled area capable of producing non-exchangeable OBT activities above the natural levels. Our analyses showed that non-exchangeable OBT activities in the collected samples were very low, ranging from below the detection limit (ca 0.7 Bq kg(-1) of dry material) to ca 2 Bq kg(-1) of dry material. These values are similar to the natural tritium background measured in water samples. No discrepancies can be shown between fern samples and oak tree leaf samples or between samples collected inside and outside the research site.  相似文献   

10.
The aim of this research was to evaluate the possible contamination by heavy metals of milk from cows bred on various farms in Calabria. The concentrations of heavy metals were determined in 40 samples of bovine milk from the various dairy farms. Each sample, homogenized and powdered, was mineralized in a microwave oven. Quantitative analyses of Cd, Cr, Cu, Pb and Se were performed using an atomic absorption spectrophotometer with graphite furnace; As was analyzed by hot vapor generation technique and Zn with the flame method. As regards toxic heavy metals, highest values are those of As (g.m. 37.90 microg/kg w.w.) and Pb (g.m. 1.32 microg/kg w.w.), while lowest concentrations are those of Cd (g.m. 0.02 microg/kg w.w). With regard to essential metals, Zn (g.m. 2016 microg/kg w.w) and Se (g.m. 13.24 microg/kg w.w.) showed the highest concentrations, followed by Cr (g.m. 2.03 microg/kg w.w.) and Cu (g.m. 1.98 microg/kg w.w.). Further investigations of the levels of heavy metals (As) in a greater number of milk samples from various zones of Calabria are necessary, both to examine this problem from the clinical epidemiological point of view and to identify the possible causes of milk contamination.  相似文献   

11.
Although several studies have reported the ubiquitous occurrence of parabens in human specimens and the environment, little is known about the accumulation of these estrogenic chemicals in fish and birds. In this study, accumulation profiles of six parabens and their metabolites were determined in 254 tissue (including liver, kidney, egg, and plasma) samples from 12 species of fish and seven species of birds collected from inland, coastal, and remote aquatic ecosystems. In addition, liver and kidney tissues from black bears were analyzed. Methyl paraben (MeP) was found in a majority of the tissues, with the highest concentration (796 ng/g (wet weight [wet wt])) found in the liver of a bald eagle from Michigan. 4-Hydroxy benzoate (HB) was the major metabolite, found in 91% of the tissue samples analyzed at concentrations as high as 68,600 ng/g, wet wt, which was found in the liver of a white-tailed sea eagle from the Baltic Sea coast. The accumulation pattern of MeP and 4-HB varied, depending on the species. The mean concentrations of MeP measured in fishes from Michigan, New York, and Florida waters were < 2.01 (fillet), 152 (liver), and 32.0 (liver) ng/g, wet wt, respectively, and the corresponding 4-HB concentrations were 39.5, 10,500, and 642 ng/g, wet wt. The mean hepatic and renal concentrations of 4-HB in black bears were 1,720 and 1,330 ng/g, wet wt, respectively. The concentrations of MeP and 4-HB were significantly positively correlated with each other in various tissues and species, which suggested a common source of exposure to these compounds in fish and birds. Trace concentrations of MeP and 4-HB also were found in the tissues of albatrosses from Midway Atoll, Northwestern Pacific Ocean, which suggested widespread distribution of these compounds in the marine environment.  相似文献   

12.
The concentrations of aluminium (Al), arsenic (As), beryllium (Be), cadmium (Cd), chromium (Cr), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb), tin (Sn), thallium (Tl), vanadium (V), and zinc (Zn) were determined in soil samples collected in Alcalá de Henares (Madrid, Spain). Human health risks derived from metal inhalation and ingestion of soils were also assessed. For noncarcinogenic risks, the current levels of metals were usually lower than those considered as safe for the general population. With respect to the potentially carcinogenic elements As, Be, Cd, and Cr, the concentrations of Be, Cd, and Cr were lower than the reference values, while the average As concentration (3.4 microg/g) was higher than the safety limit for risk cancer. In general terms, the potential human health impact of ingestion/inhalation through soils of the analyzed elements seems to be rather small.  相似文献   

13.
In order to assess soil As contamination and potential risk for human, soil, paddy rice, vegetable and human hair samples from the areas near the industrial districts in Chenzhou, southern China were sampled and analyzed. The results showed that the anthropogenic industrial activities have caused in local agricultural soils to be contaminated with As in a range of 11.0-1217 mg/kg. The GIS-based map shows that soil contamination with As occurred on a large scale, which probably accounted for up to 30% of the total area investigated. Soil As concentration abruptly decreased with an increase in the distance from the polluting source. High As concentrations were found in the rice grain that ranged from 0.5 to 7.5 mg/kg, most of which exceed the maximal permissible limit of 1.0 mg/kg dry matter. Arsenic accumulated in significantly different levels between leafy vegetables and non-leafy vegetables. Non-leafy vegetables should be recommended in As-contaminated soils, as their edible parts were found in relatively low As level. Arsenic concentrations in 95% of the total human hair samples in the contaminated districts were above the critical value, 1.0 mg/kg, set by the World Health Organization. Arsenic could be enriched in human hair to very high levels without being affected by As containing water. The results revealed that the soils and plants grown on them are major contributors to elevate hair As in the industrial population. Therefore, the potential impact on human health of ingestion/inhalation of soil As around the industrial districts seems to be rather serious. Hence proper treatments for As contaminated soils are urgently needed to reduce the contamination.  相似文献   

14.
Large-scale studies are essential to assess the emission patterns and spatial distribution of organohalogenated pollutants (OHPs) in the environment. Bird eggs have several advantages compared to other environmental media which have previously been used to map the distribution of OHPs. In this study, large-scale geographical variation in the occurrence of OHPs, such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and organochlorine pesticides (OCPs), was investigated throughout Europe using eggs of a terrestrial residential passerine species, the great tit (Parus major). Great tit eggs from 22 sampling sites, involving urban, rural and remote areas, in 14 European countries were collected and analysed (5-8 eggs per sampling site). The environmentally most important congeners/compounds of the analysed pollutants were detectable in all sampling locations. For PCBs, PBDEs and OCPs, no clear geographical contamination pattern was found. Sum PCB levels ranged from 143 ng/g lipid weight (lw) to 3660 ng/g lw. As expected, PCB concentrations were significantly higher in the sampled urban compared to the remote locations. However, the urban locations did not show significantly higher concentrations compared to the rural locations. Sum PBDEs ranged from 4.0 ng/g lw to 136 ng/g lw. PBDEs were significantly higher in the urbanized sampling locations compared to the other locations. The significant, positive correlation between PCB and PBDE concentrations suggests similar spatial exposure and/or mechanisms of accumulation. Significantly higher levels of OCPs (sum OCPs ranging from 191 ng/g lw to 7830 ng/g lw) were detected in rural sampling locations. Contamination profiles of PCBs, PBDEs and OCPs differed also among the sampling locations, which may be due to local usage and contamination sources. The higher variance among sampling locations for the PCBs and OCPs, suggests that local contamination sources are more important for the PCBs and OCPs compared to the PBDEs. To our knowledge, this is the first study in which bird eggs were used as a monitoring tool for OHPs on such a large geographical scale.  相似文献   

15.
As part of the first environmental assessment within Montevideo Harbour, in summer and winter of 1998, sediments samples were collected at eight locations to determine the spatial distribution of anthropogenic pollutants. Muddy sediments with high organic matter content dominate the study area. Heavy metal levels indicated that sediments were highly polluted with Zn (overall mean: 312+/-102 microg g(-1) dry sediment), Pb (85+/-31), Cu (89+/-25), Cr (162+/-62), and Hg (0.63+/-0.3) and moderately with Ni (30+/-2) and Ag (1.2+/-0.4). Depending on location and season, aliphatic hydrocarbons reached from 21 to 120 microg g(-1), while the unresolved complex mixture represented up to 76% of the total aliphatic fraction. Total PAH concentrations ranged from 1.56 to 90.44 microg g(-1); except at one location, petroleum derivatives were identified as main local source. The results pointed out that almost all the harbour area presented some substances that can cause adverse biological effects, especially in the inner region where all metals are above PEL levels. Principal components analysis confirmed that the inner harbour region is most severely affected by the pollutants and it was possible to differentiate three regions according to their environmental quality.  相似文献   

16.
Polybrominated diphenyl ethers (PBDEs) have been determined in 30 samples, including soil, biota and plant collected from an electronic waste recycling site and its vicinage towns. Polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and dibenzo-furans (PCDD/Fs) were also simultaneously analyzed in 20 samples. PBDEs were detected in all soil samples and the highest was up to 789 ng/g dry weight (dw). The toxic equivalency (TEQ) of PCBs and PCDD/Fs detected in E-waste recycling site is significant higher than those in the vicinage samples. Biota and plant were also contaminated with high level of PBDEs, PCBs and PCDD/Fs in this area. High levels of the three kinds of organic compounds in the environmental samples showed that the E-waste recycling have induced serious environmental problems.  相似文献   

17.
We evaluated the accumulation and distribution of major and trace elements in agricultural soils of District 03 (DR03) in the State of Hidalgo, Mexico, irrigated with raw wastewaters for an average of 20 years. Samples of topsoils (0-30 cm depth) were extracted using a modified Tessier method. Total concentrations of the species tested were in the ranges of 675-1176 mg K kg(-1), 277.9-1001 mg Na kg(-1), 6,708-81,854 mg Ca kg(-1), 23,800-106,974 mg Mg kg(-1), 9.2-123.8 mg B kg(-1), 0.6-1.9 mg Cd kg(-1), 11.6-27.4 mg Cr kg(-1), 3.9-47.0 mg Pb kg(-1). Concentrations of As and Hg were very low. Concentrations of total Cd, Cr and Pb were generally below the maximum permissible levels set by the regulations of the European Union except for cadmium, which was in the middle of the maximum European range allowed for two soils. Regarding lead, one soil (S5) could reach the maximum permissible level of the EU in 6 more years of continued irrigation. On the other hand, contents of Pb in the most mobile fractions ("e" in this work) were significant (range: 3-28%). This distribution translated into concentrations of soluble plus exchangeable lead of approximately 2 mg Pb kg(-1) in three of six soils, significantly higher than the Swiss tolerance limit of 1.0 mg Pb kg(-1) for mobile fractions of lead in soils. Multivariate analysis of the data (Pearson correlation and principal component analysis) quantitatively confirmed that: (i) there is a strong covariance between boron contents and several variables representing the salinity of soils (electrolytic conductivity, a variety of alkaline and alkaline-earth total and fraction concentrations). It appears that there is a problem with high boron content in soils, although the salinity is high only for one of the soils (S3); (ii) a significant correlation among irrigation time, lead content (total, fraction easily exchangeable and bound to organic matter and sulfides) and organic carbon in soils was found; (iii) another association among irrigation time, total contents of cadmium, chromium and boron, and organic carbon was observed.  相似文献   

18.
Sediments used in this study were collected from different depths of eight sites in East China Sea in November 2002. The levels and distribution patterns of the selected organochlorine pesticides (OCPs=p,p'-DDT, o,p'-DDT, p,p'-DDE, p,p'-DDD, alpha-, beta-, gamma- and delta-HCH) in samples were investigated by the technique of sonication extraction followed by the analysis of gas chromatography (GC) coupled with a micro-electron capture detector (muECD). The concentrations of SigmaHCH and SigmaDDT in the surface sediments were in the range of <0.05-1.45 ng/g (mean 0.76 ng/g), <0.06-6.04 ng/g (mean 3.05 ng/g) based on dry weight (dw), respectively. In the vertical distributions, the SigmaHCH and SigmaDDT were in the range of <0.05-2.52 ng/g, <0.06-10.94 ng/g dw, respectively. Residues of OCPs varied significantly with different sampling sites. SigmaDDT in the surface sediments was correlated well with total organic carbon (TOC) content (r2=0.71), while SigmaHCH showed no obvious correlation. The distribution showed that the sediments from the vicinity estuary or near shore had higher TOC contents, and higher OCPs concentrations. The contamination record indicated an extensive use of OCPs in the catchments from Yangtze River in the past might greatly affect the OCP residues.  相似文献   

19.
PCB levels in fish (collected from local rivers), atmosphere and human milk samples have been studied to determine the exposure levels of PCBs for local residents and e-waste workers in Guiyu, a major electronic waste scrapping center in China. The source appointment and correlation analyses showed that homologue composition of PCBs in 7 species of fish were consistent and similar to commercial PCBs Aroclor 1248. PCB levels in air surrounding the open burning site were significantly higher than those in residential area. Inhalation exposure contributed 27% and 93% to the total body loadings (the sum of dietary and inhalation exposure) of the local residents, and e-waste workers engaged in open burning respectively. Total PCB concentrations in human milk ranged from N.D. to 57.6 ng/g lipid, with an average of 9.50 ng/g lipid. The present results indicated that commercial PCBs derived from e-waste recycling are major sources of PCBs accumulating in different environmental media, leading to the accumulation of high chlorinated biphenyls in human beings.  相似文献   

20.
The levels of 1,1,1-trichloro-bis-2,2'-(4-chlorophenyl) ethane (p,p'-DDT) and its metabolites, hexachlorobenzene (HCB), hexachlorocyclohexane isomers (HCHs), chlordanes (trans- and cis-chlordane, oxychlordane and trans-nonachlor), 11 polychlorinated biphenyl (PCB) congeners, and 7 polybrominated diphenyl ether (PBDE) congeners were measured in 37 individual human milk samples from Kahramanmara? region, Turkey. Organochlorine pesticides were the major contaminants in the milk samples. p,p'-DDE and p,p'-DDT were detected in all samples, while beta-HCH had a detection frequency of 97%. The sum of the DDTs in human milk samples varied between 0.52 and 315.8 ng/g wet weight (ww) with a mean ratio between p,p'-DDE and p,p'-DDT equal to 31.1. p,p'-DDD could be measured only in six samples. beta-HCH was the most prevalent HCH isomer with a mean value of 2.08 ng/g ww. The mean concentration of gamma-HCH was 0.38 ng/g ww, while alpha-HCH was not detected in any sample. HCB is found in 95% of the milk samples with a mean concentration of 0.30 ng/g ww. The mean value for the sum of chlordanes was 0.39 ng/g ww, with oxychlordane and trans-nonachlor being the principal contributors. PCBs could be measured only in 8 out of 37 samples and their concentration ranged between <0.15 and 1.92 ng/g ww for the sum of PCBs. PCB profiles were dominated by congeners 153, 180 and 138. PBDEs were detected only in 3 out of 37 samples, with the highest value being 0.014 ng/g ww (0.40 ng/g lipid weight) and BDE 47 was the dominant congener. Although the number of samples is relatively low and they are not representative for the whole Turkish population, the results of the present study are important to provide additional data on the concentrations of persistent organochlorinated pollutants in Turkey and show as first the PBDE levels in Turkish population.  相似文献   

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