水产品中全氟辛酸和全氟辛烷磺酸检测技术 及污染现状

全氟辛酸(PFOA)和全氟辛烷磺酸(PFOS)是环境中广泛存在、较为典型的两种全氟化合物。针对水产品中PFOA和PFOS的检测技术和污染现状进行研究,进而研究其暴露途径、生物富集规律等内容,并基于此预测污染物环境分布、环境行为,以及相应地制定环境水和水产品质量安全标准,对于确保消费者食用安全具有重要意义。本文总结、分析了水产品中PFOA和PFOS的检测技术研究进展,及水环境和水产品中污染情况,对目前存在的问题及今后的研究方向进行了讨论和展望,以期为中国水产品中全氟化合物的监控和质量安全风险评估提供参考。     

Perfluorinated contaminants in sediments and aquatic organisms collected from shallow water and tidal flat areas of the Ariake Sea, Japan: environmental fate of perfluorooctane sulfonate in aquatic ecosystems

Perfluorinated compounds (PFCs), such as perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), perfluorononanoate (PFNA), perfluorohexane sulfonate (PFHS), and perfluorooctane sulfonamide (PFOSA) are widely distributed in aquatic ecosystems. Despite studies reporting the occurrence of PFCs in aquatic organisms, the fate of PFCs in tidal flat and marine coastal ecosystems is not known. In this study, we determined concentrations of PFOS, PFOA, PFNA, PFHS, and PFOSA in sediments; benthic organisms, including lugworm, mussel, crab, clam, oyster, and mudskipper fish from tidal flat; and shallow water species, such as filefish, bream, flounder, shark, finless porpoise, gull, and mallard collected from the Ariake Sea, Japan. PFOS and PFOA were detected in most of the samples analyzed, followed by PFNA, PFOSA, and PFHS. In shallow water species, PFOS was the dominant contaminant, and elevated concentrations were found in higher trophic level species, such as marine mammals and omnivorous birds. These results suggest biomagnification of PFOS through the coastal food chain. In contrast, PFOA was the most abundant compound in tidal flat organisms and sediments. PFOA concentrations in sediments, lugworms, and omnivorous mudskippers in tidal flat were approximately 1 order of magnitude greater than the levels of PFOS. This indicates differences in exposure pattern and bioavailability of PFOS and PFOA between shallow water and tidal flat organisms. The accumulation profiles of PFCs were compared with those of organochlorines (polychlorinated biphenyls, PCB), organotin (tributyltin,TBT), and polycyclic aromatic hydrocarbons (PAHs) in tidal flat and shallow water samples collected from the Ariake Sea. Concentrations of PFCs in sediments and in tidal flat organisms were significantly lower than that found for PCBs, TBT, and PAHs. Nevertheless, PFOS concentrations in shallow water species were comparable to and/or significantly greater than those of other classes of contaminants. This implies that the aqueous phase is a major sink for PFCs, which is different from what was observed for nonpolar organic pollutants.     

Perfluorinated surfactants in surface, subsurface water and microlayer from Dalian Coastal waters in China

Two predominant perfluorinated compounds (PFCs), Perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA), in surface water (SW, 0-20 cm), subsurface water (SSW, > 30 cm depth), and sea surface microlayer (SML, 50 microm thickness) were measured from Dalian Coastal waters in China. The SML samples were collected using glass-plate dipping method. Analysis of the PFCs was conducted through solid-phase extraction, followed by LC/MS-SIM. The PFC's concentrations in SW samples were consistent with previously reported data in this region. Significantly higher concentrations of PFCs were found in SML samples than corresponding SSW samples. The enrichment factors (EF = C(SML)/C(SSW)) for PFOS were as high as 24-109 atthree near-shore sites. The concentration in SW was also generally higher than corresponding SSW samples, giving C(SW)/C(SSW) mean ratios of 1.5 and 1.4 for PFOS and PFOA, respectively. This apparent enrichment of PFCs in surface water, especially in the microlayer, has implications for designing measurement techniques, understanding their distributions, and sea spray-mediated transport in the environment.     

Perfluorinated compounds in the Cape Fear Drainage Basin in North Carolina

Concern over perfluorinated organic compounds (PFCs), e.g., perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), is due to a number of recent studies which show that the PFCs are persistent, bioaccumulative, and toxic in animals. Despite sustained interest in this topic, little information is available concerning the environmental distributions of the compounds. In this study, a new method was developed for the analysis of 10 target PFCs and its performance was examined in a systematic evaluation of surface water in the Cape Fear River Basin in North Carolina. One hundred samples from 80 different locations were collected during the spring of 2006. Detectable levels of the target PFCs were found in all samples, and were comparable to values reported previously, with maximum PFOS at 132 ng/L, PFOA at 287 ng/L, perfluorononanoic acid (C9) at 194 ng/L, and perfluoroheptanoic acid (C7) at 329 ng/L. In general, the lowest concentrations of the PFCs were found in the smallest tributaries while the highest levels were found in middle reaches of the Drainage Basin. Variability of PFC concentrations suggests a series of source inputs throughout the Basin. Seventeen sample sites (22%) had PFOS concentrations greater than 43 ng/L, a conservative safe water concentration estimated to be protective of avian life. In addition, a total of 26 sites (32%) had PFOA concentrations above 40 ng/L.     

Trends in exposure to polyfluoroalkyl chemicals in the U.S. Population: 1999-2008

Since 2002, practices in manufacturing polyfluoroalkyl chemicals (PFCs) in the United States have changed. Previous results from the National Health and Nutrition Examination Survey (NHANES) documented a significant decrease in serum concentrations of some PFCs during 1999-2004. To further assess concentration trends of perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), perfluorohexane sulfonate (PFHxS), and perfluorononanoate (PFNA), we analyzed 7876 serum samples collected from a representative sample of the general U.S. population ≥12 years of age during NHANES 1999-2008. We detected PFOS, PFOA, PFNA, and PFHxS in more than 95% of participants. Concentrations differed by sex regardless of age and we observed some differences by race/ethnicity. Since 1999-2000, PFOS concentrations showed a significant downward trend, because of discontinuing industrial production of PFOS, but PFNA concentrations showed a significant upward trend. PFOA concentrations during 1999-2000 were significantly higher than during any other time period examined, but PFOA concentrations have remained essentially unchanged during 2003-2008. PFHxS concentrations showed a downward trend from 1999 to 2006, but concentrations increased during 2007-2008. Additional research is needed to identify the environmental sources contributing to human exposure to PFCs. Nonetheless, these NHANES data suggest that sociodemographic factors may influence exposure and also provide unique information on temporal trends of exposure.     

Perfluorooctanesulfonate and related fluorochemicals in albatrosses, elephant seals, penguins, and polar skuas from the Southern Ocean

Perfluorinated chemicals (PFCs) have been used as surfactants in industrial and commercial products for over 50 years. Earlier studies of the geographical distribution of PFCs focused primarily on the Northern Hemisphere, while little attention was paid to the Southern Hemisphere. In this study, livers from eight species of albatrosses, blood from elephant seal, and blood and eggs from penguins and polar skua collected from the Southern Ocean and the Antarctic during 1995-2005 were analyzed for 10 PFCs. In addition, for comparison with the Southern Ocean samples, we analyzed liver, sera, and eggs from two species of albatrosses from Midway Atoll in the North Pacific Ocean. Perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA) were found in livers of albatrosses from the Southern Ocean. PFOS was the major contaminant, although the concentrations were <5 ng/g, wet wt, in 92% of the albatross livers analyzed. PFOA was detected in 30% of the albatross livers, with a concentration range of <0.6-2.45 ng/g,wet wt. Other PFCs, including long-chain perfluorocarboxylates (PFCAs), were below the limits of quantitation in livers of albatrosses from the Southern Ocean. In liver, sera, and eggs of albatrosses from the North Pacific Ocean, long-chain PFCAs (perfluorononanoate, perfluorodecanoate, perfluoroundecanoate, and perfluorododecanoate) were found at concentrations similar to those of PFOS and PFOA. The mean concentration of PFOS in livers of Laysan albatrosses from the North Pacific Ocean (5.1 ng/g, wet wt) was higher than that in several species of albatrosses from the Southern Ocean (2.2 ng/g, wetwt). Species-specific differences in the concentrations of PFOS were noted among Southern Ocean albatrosses, whereas geographical differences in PFOS concentrations among the Indian Ocean, South Pacific Ocean, and South Atlantic Ocean were insignificant. Concentrations of PFOS and PFOA were, respectively, 2- and 17-fold higher in liver than in sera of Laysan albatrosses. PFOS was found in the blood of elephant seals from Antarctica at concentrations ranging from <0.08 to 3.52 ng/mL. PFOS was found in eggs (2.1-3.1 ng/g) and blood (<0.24-1.4 ng/ mL) of polar skuas but was not detected in penguins from Antarctica. Our study documents the existence of low but detectable levels of PFOS and PFOA in Southern Hemisphere fauna, suggesting distribution of these compounds on a global scale.     

中国沿海地区鸡蛋中全氟化合物污染水平及分布

为探究我国沿海地区鸡蛋中全氟化合物(perfluorinated compounds,PFCs)的污染水平及分布规律,采用分散固相萃取结合高效液相色谱-串联质谱的方法分析了我国沿海9个省/直辖市1 060份鸡蛋样品中17种PFCs的残留水平。结果表明,鸡蛋中PFCs检出率较低,均低于50%;检出的PFCs以中短链为主,占∑PFCs的82%。各省市鸡蛋样品中PFCs的残留受环境中PFCs影响较大,江苏鸡蛋样品中∑PFCs残留最高(1.24μg/kg),浙江最低(0.124μg/kg)。江苏主要全氟化合物残留为全氟辛烷磺酸(perfluorooctane sulfonate,PFOS),其他各省市为全氟戊酸。对鸡蛋中PFOS、全氟辛酸以及除此之外的短、中、长链PFCs进行风险评价,其危害指数均低于1,不具即时危害。     

Determinants of fetal exposure to polyfluoroalkyl compounds in Baltimore, Maryland

Polyfluoroalkyl compounds (PFCs), such as perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA), are ubiquitous, man-made chemicals. Human data suggest that in utero exposures to these chemicals occur and some evidence of developmental toxicity in animals exists. To assess the distribution and determinants of fetal exposure to PFCs, we analyzed cord serum samples from 299 singleton newborns delivered between 2004 and 2005 in Baltimore, MD for 10 PFCs by employing on-line solid-phase extraction coupled with reversed-phase high-performance liquid chromatography-tandem mass spectrometry. PFOS and PFOA were detected in 99 and 100% of umbilical cord sera, with geometric mean concentrations of 4.9 and 1.6 ng/mL, respectively. PFOS and PFOA concentrations were highly correlated (Pearson's r = 0.64 after natural log transformation, p < 0.01). Eight other PFCs were detected less frequently and at lower concentrations than PFOS and PFOA. Geometric mean concentrations of PFOS for Asians (6.0 ng/mL) and Blacks (5.1 ng/mL) were higher than those for Whites (4.2 ng/mL), while PFOA levels were more evenly distributed by race. Other maternal demographic and socioeconomic characteristics, including age, education, marital status, and living in the city limits were not significantly associated with cord concentrations. Our findings suggest that in utero exposure to PFOS and PFOA is ubiquitous in a population of babies born in Baltimore, MD.     

江西省畜禽产品中全氟辛酸和全氟辛烷磺酸污染情况调查与分析

为了探索江西省畜禽产品中全氟辛酸（perfluorooctanoic acid,PFOA）和全氟辛烷磺酸（perfluorooctanesulfonate,PFOS）的污染现状,采用超高效液相色谱-三重四极杆串联质谱对江西省5 个畜禽主产市市售猪、鸡、鸭各组织（n=260）样品中PFOS和PFOA的污染水平进行了分析。结果表明：以湿质量计算可知,鸡血中PFOA的污染水平最高,为0.52 ng/g,其次为猪肝（0.24 ng/g）,然后依次为鸡肝（0.14 ng/g）、鸭血（0.12 ng/g）、鸭肝（0.029 ng/g）,猪肉、鸡肉、鸭肉和猪血中均未检出PFOA的污染;PFOS仅在猪肝中检出,其均值为0.20 ng/g。对人体健康风险评价结果显示,江西省猪、鸡和鸭各组织中PFOA和PFOS不会对人体健康造成即时危害。     

Indoor sources of poly- and perfluorinated compounds (PFCS) in Vancouver, Canada: implications for human exposure

Perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) are widely detected in human blood and serum and are of concern due to their potential toxicity. This study investigated the indoor sources of these compounds and their neutral precursors through a survey of 152 homes in Vancouver, Canada. Samples were collected of indoor air, outdoor air, indoor dust, and clothes dryer lint and analyzed for neutral [i.e., fluorotelomer alcohols (FTOHs), perfluorooctane sulfonamide (FOSA), and perfluorooctane sulfonamidoethanol (FOSE)] and ionic [i.e., PFOS and perfluoroalkyl carboxylates (PFCAs)] poly- and perfluorinated compounds (PFCs). Indoor air was dominated by 8:2 FTOH with a geometric mean concentration (pg/m(3)) of 2900. Among the FOSAs and FOSEs, MeFOSE exhibited the highest air concentration with a geometric mean of 380 pg/m(3). PFOA was the major ionic PFC and was detected in all indoor air samples with a geometric mean of 28 pg/m(3), whereas PFOS was below the detection limit. The results for the ionic PFCs in indoor air are the first for North America. The pattern of the neutral PFCs in house dust was also dominated by 8:2 FTOH, with a geometric mean of 88 ng/g. Dusts were enriched (relative to air) with sulfonamidoethanol (FOSE) which comprised ～22% of the total neutral PFC content compared to only ～3% in air. PFOS and PFOA were the most prominent compounds detected in dust samples. Levels of neutral PFCs in clothes dryer lint were an order of magnitude lower compared to house dust. Human exposure estimates to PFCs for adults and children showed that inhalation was the main exposure route for neutral and ionic PFCs in adults. For toddlers, ingestion of PFCs via dust was more relevant and was on the order of a few mg/day. Results from this study contribute to our understanding of exposure pathways of PFCs to humans. This will facilitate investigations of related health effects and human monitoring data.     

Ratio of perfluorochemical concentrations as a tracer of atmospheric deposition to surface waters

A major question regarding the global distribution of perfluorochemicals (PFCs) is one of transport. It has been suggested that atmospheric transport of volatile precursor compounds to remote areas and subsequent degradation to the nonvolatile PFCs is responsible for contamination of biota. This paper presents surface water PFC concentrations aimed at identifying tracers of atmospheric sources. Concentrations of PFCs including perfluorocarboxylates from C6 to C10 and perfluorooctane sulfonate (PFOS) are presented here from urban surface waters with presumably both atmospheric and nonatmospheric sources of PFCs, remote waters with only atmospheric sources of PFCs, and Lake Michigan. Perfluoroheptanoic acid (PFHpA) and perfluorooctanoic acid (PFOA) were detected in all surface water samples, and PFOS was detected in all but two samples. PFOS concentrations ranged from nondetect to 1.2 ng/L and from 2.4 to 47 ng/L in remote and urban surface waters, respectively. PFOA concentrations ranged from 0.14 to 0.66 ng/L and from 0.45 to 19 ng/L in remote and urban surface waters, respectively. The ratio of PFHpA to PFOA increased with increasing distance from nonatmospheric sources suggesting that it can be used as a tracer of atmospheric deposition of PFCs to surface waters. The ratio ranged from 0.5 to 0.9 in urban areas and from 6 to 16 in remote areas. Applying this tracer to measurements from Lake Michigan indicates that the primary source of PFCs to Lake Michigan is nonatmospheric, most likely inputs from wastewater treatment effluent.     

Trophic magnification of poly- and perfluorinated compounds in a subtropical food web

Perfluorinated compounds (PFCs) are known to biomagnify in temperate and Arctic food webs, but little is known about their behavior in subtropical systems. The environmental distribution and biomagnification of PFCs, extractable organic fluorine (EOF), and total fluorine were investigated in a subtropical food web. Surface water, sediment, phytoplankton, zooplankton, gastropods, worms, shrimps, fishes, and waterbirds collected in the Mai Po Marshes Nature Reserve in Hong Kong were analyzed. Trophic magnification was observed for perfluorooctanesulfonate (PFOS), perfluorodecanoate (PFDA), perfluoroundecanoate (PFUnDA), and perfluorododecanoate (PFDoDA) in this food web. Risk assessment results for PFOS, PFDA, and perfluorooctanoate (PFOA) suggest that current PFC concentrations in waterbird livers are unlikely to pose adverse biological effects to waterbirds. All hazard ratio (HR) values reported for PFOS and PFOA are less than one, which suggests that the detected levels will not cause any immediate health effects to the Hong Kong population through the consumption of shrimps and fishes. However, only 10-12% of the EOF in the shrimp samples was comprised of known PFCs, indicating the need for further investigation to identify unknown fluorinated compounds in wildlife.     

Serum concentrations of polyfluoroalkyl compounds in Faroese whale meat consumers

To learn the extent of human exposure to polyfluoroalkyl compounds (PFCs) in a remote fishing population, we measured, in Faroese children and pregnant women, the serum concentrations of nine PFCs, including perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), and perfluorononanoate (PFNA), by using online solid-phase extraction coupled to isotope dilution high-performance liquid chromatography-tandem mass spectrometry. The serum samples analyzed had been collected between 1993 and 2005 from 103 children 7 years of age, 79 of these children at 14 years of age, and from 12 pregnant women and their children 5 years later. PFOS was detected in all samples analyzed, and both PFOA and PFNA were detected in all but one of the samples. The concentrations found are comparable tothose reported elsewhere. Correlations between paired concentrations were poor. However, PFOS and PFNA concentrations correlated well with the frequency of pilotwhale dinners and with concentrations of mercury and polychlorinated biphenyls. One whale meal every two weeks increased the PFOS concentration in 14-year-olds by about 25% and PFNA by 50%. The high frequency of detection of most PFCs suggests widespread exposure in the Faroe Islands already by the early 1990s, with whale meat being an important source.     

Analysis of Trace Metals and Perfluorinated Compounds in 43 Representative Tea Products from South China

Six trace metals (Cd, Pb, Cr, Cu, Zn, and Mn) and 2 perfluorinated compounds (PFCs), perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), were analyzed in 43 representative tea products (including 18 green, 12 Oolong, and 13 black teas) from 7 main tea production provinces in China, using the atomic absorption spectrophotometer for trace metals analysis and HPLC‐MS/MS for PFOS and PFOA analysis. The average contents of the 3 essential metals Mn, Cu, and Zn ions in the tea samples were 629.74, 17.75, and 37.38 mg/kg, whereas 3 toxic metals Cd, Cr, and Pb were 0.65, 1.02, and 1.92 mg/kg, respectively. The contents of heavy metals in the 3 types of tea were in the order of black tea > Oolong tea > green tea. Both PFOS and PFOA contents were low and PFOA content was higher than PFOS in the tea samples. The highest concentration of PFOA was 0.25 ng/g dry weight found in a Hunan green tea. The Principal component analysis was performed with the trace metals and PFCs to analyze the relationships of these indices. The results showed that black teas had higher trace metals and PFCs than green and Oolong teas, and the teas from Hunan and Zhejiang provinces had higher Pb and Cr than others.     

Trans-placental transfer of thirteen perfluorinated compounds and relations with fetal thyroid hormones

While the results of animal studies have shown that perfluorinated compounds (PFCs) can modulate concentrations of thyroid hormones in blood, limited information is available on relationships between concentrations of PFCs in human blood serum and fetal thyroid hormones. The relationship between concentrations of PFCs in blood and fetal thyroid hormone concentrations or birth weight, and ratios of major PFCs between maternal and fetal serum were determined. Concentrations of PFCs were measured in blood serum of pregnant women (n = 44), fetal cord blood serum (n = 43) and breast milk (n = 35). Total concentrations of thyroxin (T4), triiodothyronin (T3) and thyroid stimulating hormone (TSH) in blood serum were also quantified. The ratios of major PFCs in maternal versus fetal serum were 1:1.93, 1.02, 0.72, and 0.48 for perfluorotridecanoic acid (PFTrDA), perfluorooctanoic acid (PFOA), perfluorohexane sulfonate (PFHxS), and perfluorooctane sulfonate (PFOS), respectively. Fetal PFOS, PFOA, PFTrDA and maternal PFTrDA were correlated with fetal total T4 concentrations, but after adjusting for major covariates, most of the relationships were no longer statistically significant. However, the significant negative correlations between maternal PFOS and fetal T3, and maternal PFTrDA and fetal T4 and T3 remained. Since thyroid hormones are crucial in the early development of the fetus, its clinical implication should be evaluated. Given the observed trans-placental transfer of PFCs, efforts should be also made to elucidate the exposure sources among pregnant women.     

Perfluorinated compounds in fish and blood of anglers at Lake Möhne, Sauerland area, Germany

Perfluorinated compounds (PFCs) were measured in fish samples and blood plasma of anglers in a cross-sectional study at Lake Mo?hne, Sauerland area, Germany. Human plasma and drinking water samples were analyzed by solid phase extraction, high-performance liquid chromatography (HPLC), and tandem mass spectrometry (MS/MS). PFCs in fish fillet were measured by ion pair extraction followed by HPLC and MS/MS. PFOS concentrations in 44 fish samples of Lake Mo?hne ranged between 4.5 and 150 ng/g. The highest median PFOS concentrations have been observed in perches (median: 96 ng/g) and eels (77 ng/g), followed by pikes (37 ng/g), whitefish (34 ng/g), and roaches (6.1 ng/g). In contrast, in a food surveillance program only 11% of fishes at retail sale contained PFOS at detectable concentrations. One hundred five anglers (99 men, 6 women; 14-88 years old; median 50.6 years) participated in the human biomonitoring study. PFOS concentrations in blood plasma ranged from 1.1 to 650 μg/L (PFOA: 2.1-170 μg/L; PFHxS: 0.4-17 μg/L; LOD: 0.1 μg/L). A distinct dose-dependent relationship between fish consumption and internal exposure to PFOS was observed. PFOS concentrations in blood plasma of anglers consuming fish 2-3 times per month were 7 times higher compared to those without any fish consumption from Lake Mo?hne. The study results strongly suggest that human internal exposure to PFC is distinctly increased by consumption of fish from PFC-contaminated sites.     

Perfluorinated acid isomer profiling in water and quantitative assessment of manufacturing source

A method for isomer profiling of perfluorinated compounds (PFCs) in water was developed and applied to quantitatively assess the contributions from electrochemical (ECF) and telomer manufacturing processes around source regions of North America, Asia, and Europe. With the exception of 3 sites in Japan, over 80% of total perfluorooctanoate (PFOA, C(7)F(15)COO(-)) was from ECF, with the balance attributable to strictly linear (presumably telomer) manufacturing source(s). Comparing PFOA isomer profiles in samples from China, with PFOA obtained from a local Chinese manufacturer, indicated <3% difference in overall branched isomer content; thus, exclusive contribution from local ECF production cannot be ruled out. In Tokyo Bay, ECF, linear-telomer, and isopropyl-telomer sources contributed to 33%, 53%, and 14% of total PFOA, respectively. Perfluorooctane sulfonate (PFOS, C(8)F(17)SO(3)(-)) isomer profiles were enriched in branched content (i.e., >50% branched) in the Mississippi River but in all other locations were similar or only slightly enriched in branched content relative to historical ECF PFOS. Isomer profiles of other PFCs are also reported. Overall, these data suggest that, with the exception of Tokyo Bay, ECF manufacturing has contributed to the bulk of contamination around these source regions, but other sources are significant, and remote sites should be monitored.     

Health risks in infants associated with exposure to perfluorinated compounds in human breast milk from Zhoushan, China

Recent studies have reported the ubiquitous distribution of perfluorinated compounds (PFCs), especially perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA), in wildlife and human whole blood or serum. In 2003 a solid phase extraction method was developed, which allowed the measurement of PFCs in human breast milk. In the present study, PFCs in samples of human breast milk from 19 individuals from Zhoushan, China, were analyzed by modifying a previously established method, based on weak-anion exchange extraction. PFOS and PFOA were the two dominant chemicals detected in all the milk samples. Concentrations of PFOS and PFOA ranged from 45 to 360 ng/L and 47 to 210 ng/L, respectively. The maximum concentrations of other PFCs were 100 ng/L for perfluorohexanesulfonate (PFHxS), 62 ng/L for perfluorononanoate (PFNA), 15 ng/L for perfluorodecanoate (PFDA) and 56 ng/L for perfluoroundecanoate (PFUnDA). Statistically significant correlations between various PFCs suggested a common exposure source to humans. No statistically significant correlation was found between concentrations of either PFOS or PFOA and maternal age, weight, or infant weight. Rate of consumption of fish was found to be positively correlated with PFNA, PFDA, and PFUnDA concentrations. Daily intake of PFOS for the child via breast milk with greater PFOS concentrations exceeded the predicted conservative reference dose in 1 of 19 samples, indicating that there may be a small potential risk of PFOS for the infants in Zhoushan via the consumption of breast milk.     

Occurrence and fate of perfluorochemicals in soil following the land application of municipal biosolids

The recent implementation of soil and drinking water screening guidance values for two perfluorochemicals (PFCs), perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) by the U.S. Environmental Protection Agency (EPA), reflects the growing concerns regarding the presence of these persistent and bioaccumulative chemicals in the natural environment. Previous work has established the potential risk to the environment from the land application of industrially contaminated biosolids, but studies focusing on environmental risk from land application of typical municipal biosolids are lacking. Thus, the present study investigated the occurrence and fate of PFCs from land-applied municipal biosolids by evaluating the levels, mass balance, desorption, and transport of PFCs in soils receiving application of municipal biosolids at various loading rates. This study is the first to report levels of PFCs in agricultural soils amended with typical municipal biosolids. PFOS was the dominant PFC in both biosolids (80-219 ng/g) and biosolids-amended soil (2-483 ng/g). Concentrations of all PFCs in soil increased linearly with increasing biosolids loading rate. These data were used to develop a model for predicting PFC soil concentrations in soils amended with typical municipal biosolids using cumulative biosolids loading rates. Mass balance calculations comparing PFCs applied vs those recovered in the surface soil interval indicated the potential transformation of PFC precursors. Laboratory desorption experiments indicated that the leaching potential of PFCs decreases with increasing chain length and that previously derived organic-carbon normalized partition coefficients may not be accurate predictors of the desorption of long-chain PFCs from biosolids-amended soils. Trace levels of PFCs were also detected in soil cores from biosolids-amended soils to depths of 120 cm, suggesting potential movement of these compounds within the soil profile over time and confirming the higher transport potential for short-chain PFCs in soils amended with municipal biosolids.     

Perfluorinated compounds in house dust from Ohio and North Carolina, USA

The perfluoroalkyl acids (PFAAs), including perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), have come under increasing scrutiny due to their persistence, global distribution, and toxicity. Given that their human exposure routes remain poorly characterized, the potential role of house dust needs to be more completely evaluated. In this study, new methods for the analysis of 10 PFAAs and three fluorinated telomer alcohols (FTOHs) were developed for dust samples collected from homes (n = 102) and day care centers (n = 10) in Ohio and North Carolina in 2000-2001. FTOHs were measured by GC/ MS and PFAAs were analyzed by LC-MS/MS. PFOS and PFOA were the most prominent compounds detected, occurring in over 95% of the samples at median concentrations of 201 and 142 ng/g of dust, respectively. Maximal concentrations of PFOS were 12 100 ng/g (95th percentile, 2240 ng/g), PFOA 1960 ng/g (95th percentile, 1200 ng/g), and perfluorohexanesulfonate (PFHS) 35 700 ng/g (95th percentile, 2300 ng/g). The 8:2 FTOH, which is volatile and can degrade to PFOA, had a maximum concentration of 1660 ng/g dust (95th percentile, 669 ng/g). These results indicate that perfluorinated compounds are present in house dust at levels that may represent an important pathway for human exposure.