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1.
建立了水、沉积物及土壤中13种全氟化合物(PFCs)的富集、净化、浓缩的前处理方法及快速液相色谱三重四级杆串联质谱的分析方法。9种全氟羧酸、2种典型全氟磺酸、2种磺酰铵衍生前体物的响应因子与质量浓度的线性关系良好。添加回收实验表明,13种全氟化合物在水、土壤和沉积物中的回收率为52.3%~119.3%,变异系数为2.3%~19.4%,方法检出限分别为0.015~0.472 ng/L、0.012~0.875 ng/g、0.004~0.743 ng/g。该法成功应用于实际样品的测定,沉积物和土壤中分别检测到3种和10种全氟化合物。  相似文献   

2.
固相萃取-UPLC-MS/MS法测定水中全氟化合物   总被引:1,自引:0,他引:1  
水样中全氟辛酸、全氟辛烷磺酸钾、全氟丁酸、全氟丁烷磺酸经弱阴离子交换固相萃取柱富集净化后,用超高效液相色谱-串联质谱法测定。通过优化样品前处理条件和仪器条件,使4种全氟化合物在0.05μg/L~10.0μg/L范围内线性良好,相关系数为0.998 9~0.999 9,方法检出限为0.27 ng/L~0.96 ng/L。空白水样3个质量浓度水平的加标回收率为73.1%~91.3%,6次测定结果的RSD为7.4%~14.3%。  相似文献   

3.
大伙房水库属于全国城市供水九大重点水源地之一,作为辽宁省重要的饮用水水源地,库区水质直接影响该区域人民饮水安全及身体健康。对大伙房水库表层水体、沉积物和鱼类样品中全氟化合物(PFAS)的赋存特征及可能的来源进行分析,并运用健康风险商值法评估PFAS的潜在健康风险。结果表明,库区表层水体中ρ(ΣPFAS)为1.18~8.19 ng/L,主要污染物为全氟辛酸及其盐类化合物(PFOA)和全氟戊基羧酸(PFPA),其浓度水平随时间呈下降趋势;沉积物中只检出3种污染物,分别为PFOA、全氟十一烷基羧酸(PFUnA)和全氟十二烷基羧酸(PFDoDA),ω(ΣPFAS)为0.16~0.48 ng/g;不同鱼类样品中ω(ΣPFAS)由高到低依次为:武昌鱼(2.49 ng/g)>鲤鱼(2.30 ng/g)>白鲢(2.02 ng/g)>花鲢(2.01 ng/g),主要污染物均为PFPA。基于主成分分析与相关性分析可知,大伙房水库库区的PFAS主要来自采矿、电镀、涂料等工业污染废水和生活污水;健康风险评估结果表明,表层水体和鱼类样品中的PFAS不存在健康风险。  相似文献   

4.
采用分段采样的方式收集杭州市2018年8月2日—3日一场降水样品,测定其中16种全氟化合物(PFCs)及主要化学组分浓度。结果发现,此次降雨过程水样的pH值范围为5.04~5.32,均为弱酸性降水,酸雨类型为复合型,检出的主要阳离子为NH+4,主要阴离子为SO2-4和NO-3;样品中检出7种中短链PFCs,包括2种全氟烷基磺酸(PFSAs)和5种全氟烷基羧酸(PFCAs),ΣPFCs质量浓度范围为4.41 ng/L~25.2 ng/L,主要污染因子全氟辛酸(PFOA)质量浓度范围为096 ng/L~13.1 ng/L;降雨过程对大气污染清除作用的统计结果表明,区域大气环境中的主要化学组分及除全氟丁酸(PFBA)之外的PFCs污染主要吸附在云下大气颗粒物上;雨水中各污染因子浓度变化特征及相关性统计结果提示,杭州市大气中PFCAs和PFSAs两类PFCs可能来自不同的污染源。  相似文献   

5.
采用C 18柱固相萃取(SPE)-三重四级杆气相色谱-质谱法同时测定水中18种含有机氯的环境内分泌干扰物,方法在0.500μg/L^100μg/L范围内线性良好,方法检出限为0.04 ng/L^0.8 ng/L,空白水样的加标回收率为61.3%~108%,6次测定结果的RSD为3.8%~18.0%。将该方法用于饮用水源水监测,18种目标化合物的测定值为未检出~1.5 ng/L,平均加标回收率为71.9%~109%,平行测定结果的RSD<15%。  相似文献   

6.
使用固相萃取-超高效液相色谱串联质谱法,测定广西3个污水处理厂(P1、P2、P3)中17种全氟和多氟烷基物质(PFASs)。结果显示,共检测出10种PFASs,检出率为33.3%~100%。进、出水中PFASs质量浓度分别为32.0~86.4和23.0~39.6 ng/L。全氟丁烷磺酸(PFBA)、全氟戊酸(PFPeA)和全氟辛酸(PFOA)是进、出水中的主要污染物。厌氧-缺氧-好氧(AAO)工艺对PFASs的去除率为49.0%;改良型序批反应器(MSBR)工艺对PFASs的去除率为72.2%,氧化沟工艺对PFASs的去除率为25.0%。P1和P3进水中的PFASs主要来源于生活污水,P2进水中的PFASs来源包括生活污水和工业废水。P1出水中的全氟十二烷酸(PFDoDA)对纳污河流的鱼类和水蚤构成高生态风险,对藻类构成中等生态风险,P2和P3出水对纳污河流构成的生态风险较低。  相似文献   

7.
建立了液液萃取一气相色谱三重四极杆质谱多反应监测同时测定水中16种持久性有机氯污染物的方法,考察了不同萃取剂不同体积对有机氯萃取效率的影响,确定了16种持久性有机氯化合物多反应监测模式(MRM)的最佳质谱条件。方法检出限为0.33 ~ 0.65 ng/L,以纯水为基体,加入16种不同浓度水平的持久性有机氯化合物作回收试验,测得回收率在80.2% ~ 103.6%之间,测定的相对标准偏差4.0% ~11.5%(n=7)。  相似文献   

8.
建立了车载顶空-气相色谱质谱法(GC/MS)测定水中22种挥发性有机物(VOCs)的方法,顶空平衡温度和平衡时间的最优设置分别为80℃和30 min。该方法各目标化合物分离良好,在目标化合物质量浓度5~100μg/L范围内,线性良好,相关系数均0.995,方法的检出限为1.16~2.88μg/L,RSD为7.71%~26.5%,加标回收率为52.3%~129%,能够满足应急监测工作的需要。  相似文献   

9.
建立了同时测定水中27种有机农药的LLE-GC-MS法。该法前处理前需调节水样pH值2,不加甲醇作为改性剂,以1:1(V/V)正己烷-石油醚为萃取溶剂进行液液萃取,GC-MS法进行检测。方法在各目标化合物质量浓度0.010~0.500 mg/L范围内线性良好,相关系数R2均0.995,检出限为0.021~0.250μg/L,加标回收率为73.6%~113.6%,相对标准偏差RSD为4.0%~14.1%,适用于水中27种有机农药的检测。  相似文献   

10.
通过对萃取和解吸条件进行优化,实现搅拌棒吸收萃取(SBSE)-热脱附-气相色谱/质谱联用以同时测定饮用水源水中16种多溴联苯单体。此法在2~50 ng/L范围内线性良好,取10 m L水样,搅拌棒吸收萃取1 h后,16种多溴联苯单体的检出限为0.5~1.1 ng/L。对实际水样进行2个质量浓度的加标回收,平均回收率为89.2%~102%。  相似文献   

11.
Material Disposal Area G is the primary low-levelradioactive waste disposal site at Los Alamos NationalLaboratory, New Mexico, and is adjacent to Pueblo of SanIldefonso lands. Pueblo residents and Los Alamos scientists areconcerned about radiological doses resulting from uptake of AreaG radionuclides by mule deer (Odocoileus hemionus) andRocky Mountain elk (Cervus elaphus), then consumption ofdeer and elk meat by humans. Tissue samples were collected fromdeer and elk accidentally killed near Area G and were analyzedfor 3H, 90Sr, total U, 238Pu, 239, 240Pu,241Am, and 137Cs. These data were used to estimatehuman doses based on meat consumption of 23 kg y-1. Humandoses were also modeled using RESRAD, and dose rates to deer andelk were estimated with a screening model. Dose estimates tohumans from tissue consumption were 2.9 × 10-3 mSv y-1and 1.6 × 10-3 mSv y-1 from deer and elk, respectively,and RESRAD dose estimates were of the same order of magnitude. Estimated dose rates to deer and elk were 2.1 × 10-4 mGyd-1 and 4.7 × 10-4 mGy d-1, respectively. Allestimated doses were significantly less than established exposurelimits or guidelines.  相似文献   

12.
Metal concentrations in deciduous tree leaves from urban areas in Poland   总被引:1,自引:0,他引:1  
Accumulation of metals in deciduous tree foliage fromurban areas in western-south Poland was monitored duringthe vegetation season of 2000 year. Concentrations of Al,Ba, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sr, Ti and Znwere measured in birch, willow, linden and maple leavesusing the ICP-AES method. Seasonal variations of metalconcentrations and their relations with sampling sitewere investigated. The most dynamic accumulation of Al,Cd, Cr, Ni and Pb was observed for examined species. Thehighest differences in element concentrations forinvestigated sites were found for Ba, Cd, Mn and Ni.Interelement correlations were investigated. In allfoliar samples synergistic relationships between Al–Crand Ca-Sr were found. Statistically significant negativecorrelations were observed only for Cd and Ti in birch leaves.  相似文献   

13.
The stable nitrogen isotope ratios of some biota have been used as indicators of sources of anthropogenic nitrogen. In this study the relationships of the stable nitrogen isotope ratios of marsh plants, Iva frutescens (L.), Phragmites australis (Cav.) Trin ex Steud, Spartina patens (Ait.) Muhl, Spartina alterniflora Loisel, Ulva lactuca (L.), and Enteromorpha intestinalis (L.) with wastewater nitrogen and land development in New England are described. Five of the six plant species (all but U. lactuca) showed significant relationships of increasing δ 15N values with increasing wastewater nitrogen. There was a significant (P < 0.0001) downward shift in the δ 15N of S. patens (6.0 ± 0.48‰) which is mycorrhizal compared with S. alterniflora (8.5 ± 0.41‰). The downward shift in δ 15N may be caused by the assimilation of fixed nitrogen in the roots of S. patens. P. australis within sites had wide ranges of δ 15N values, evidently influenced by the type of shoreline development or buffer at the upland border. In residential areas, the presence of a vegetated buffer (n = 24 locations) significantly (P < 0.001) reduced the δ 15N (mean = 7.4 ± 0.43‰) of the P. australis compared to stands where there was no buffer (mean = 10.9 ± 1.0‰; n = 15). Among the plant species, I. frutescens located near the upland border showed the most significant (R 2 = 0.64; P = 0.006) inverse relationship with the percent agricultural land in the watershed. The δ 15N of P. australis and I. frustescens is apparently an indicator of local inputs near the upland border, while the δ 15N of Spartina relates with the integrated, watershed-sea nitrogen inputs.  相似文献   

14.
Concentrations of 13 radionuclides (137Cs, 129I, 60Co, 152Eu, 90Sr, 99Tc, 241Am, 238Pu, 239,249Pu, 234U, 235U, 236U, 238U were examined in seven species of invertebrates from Amchitka and Kiska Islands, in the Aleutian Chain of Alaska, using gamma spectroscopy, inductively coupled plasma mass spectroscopy, and alpha spectroscopy. Amchitka Island was the site of three underground nuclear test (1965–1971), and we tested the null hypotheses that there were no differences in radionuclide concentrations between Amchitka and the reference site (Kiska) and there were no differences among species. The only radionuclides where composite samples were above the Minimum Detectable Activity (MDA) were 137Cs, 241Am, 239,249Pu, 234U, 235U, 236U, and 238U. Green sea urchin (Strongylocentrotus polyacanthus), giant chiton (Cryptochiton stelleri), plate limpets (Tectura scutum) and giant Pacific octopus (Enteroctopus dofleini) were only tested for 137Cs; octopus was the only species with detectable levels of 137Cs (0.262 ± 0.029 Bq/kg, wet weight). Only rock jingle (Pododesmus macroschisma), blue mussel (Mytilus trossulus) and horse mussel (Modiolus modiolus) were analyzed for the actinides. There were no interspecific differences in 241Am and 239,240Pu, and almost no samples above the MDA for 238Pu and 236U. Horse mussels had significantly higher concentrations of 234U (0.844 ± 0.804 Bq/kg) and 238U (0.730 ± 0.646) than the other species (both isotopes are naturally occurring). There were no differences in actinide concentrations between Amchitka and Kiska. In general, radionuclides in invertebrates from Amchitka were similar to those from uncontaminated sites in the Northern Hemisphere, and below those from the contaminated Irish Sea. There is a clear research need for authors to report the concentrations of radionuclides by species, rather than simply as ‘shellfish’, for comparative purposes in determining geographical patterns, understanding possible effects, and for estimating risk to humans from consuming different biota.  相似文献   

15.
We grew leek (Allium porrum) in soils of two shooting ranges heavily contaminated with heavy metals in the towns of Zuchwil and Oberuzwil in Switzerland as a bioassay to test theactivity of arbuscular mycorrhizal (AM) fungi in these soils.Soil samples were taken from (1) front of the shooting house(HOUSE), (2) the area between house and target (FIELD) and (3) the berm (BACKSTOP). Samples of Ribwort plantain (Plantagolanceolata) growing naturally within the shooting ranges werealso collected and the colonization of its roots by mycorrhizalfungi was measured. The number of AM spores in the soils wassignificantly reduced concomitant with the increase in thedegree of soil contamination with metals. In Zuchwil,mycorrhizal fungi equally colonized roots of Ribwort plantainsampled from BACKSTOP and HOUSE. In Oberuzwil, however, plantsfrom BACKSTOP had lower colonization when compared with thosesampled from HOUSE. Colonization of leek was strongly reducedin the BACKSTOP soil of Zuchwil and slightly reduced in theBACKSTOP soil of Oberuzwil when compared with plants grown inrespective HOUSE soil. Concentrations of Cd, Cr, Cu, Ni, Pb andZn in the leaves of leek grown in the BACKSTOP soil was withinthe range considered toxic for human consumption. This pointsto the high degree of bio-availability of these metal in thesesoils. Significant decrease in the number of mycorrhizal sporesin the BACKSTOP soils in Zuchwil and the low colonization ofleek roots grown in these soils point to possible changes inthe species diversity of mycorrhizal fungi in these soils.  相似文献   

16.
Kelp may be useful as a bioindicator because they are primary producers that are eaten by higher trophic level organisms, including people and livestock. Often when kelp or other algae species are used as bioindicators, the whole organism is homogenized. However, some kelp can be over 25 m long from their holdfast to the tip of the blade, making it important to understand how contaminant levels vary throughout the plant. We compared the levels of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in five different parts of the kelp Alaria nana to examine the variability of metal distribution. To be useful as a bioindicator, it is critical to know whether levels are constant throughout the kelp, or which part is the highest accumulator. Kelp were collected on Adak Island in the Aleutian Chain of Alaska from the Adak Harbor and Clam Cove, which opens onto the Bering Sea. In addition to determining if the levels differ in different parts of the kelp, we wanted to determine whether there were locational or size-related differences. Regression models indicated that between 14% and 43% of the variation in the levels of arsenic, cadmium, chromium, manganese, mercury, and selenium was explained by total length, part of the plant, and location (but not for lead). The main contributors to variability were length (for arsenic and selenium), location (mercury), and part of the plant (for arsenic, cadmium, chromium and manganese). The higher levels of selenium occurred at Clam Cove, while mercury was higher at the harbor. Where there was a significant difference among parts, the holdfast had the highest levels, although the differences were not great. These data indicate that consistency should be applied in selecting the part of kelp (and the length) to be used as a bioindicator. While any part of Alaria could be collected for some metals, for arsenic, cadmium, chromium, and manganese a conversion should be made among parts. In the Aleutians the holdfast can be perennial while the blade, whipped to pieces by winter wave action, is regrown each year. Thus the holdfast may be used for longer-term exposure for arsenic, cadmium, chromium and manganese, while the blade can be used for short-term exposure for all metals. Cadmium, lead and selenium were at levels that suggest that predators, including people, may be at risk from consuming Alaria. More attention should be devoted to heavy metal levels in kelp and other algae from Adak, particularly where they may play a role in a subsistence diets.  相似文献   

17.
Biological damage to sensitive aquatic ecosystems is among the most recognisable, deleterious effects of acidic deposition. We compiled a large spatial database of over 2000 waterbodies across southeastern Canada from various federal, provincial and academic sources. Data for zooplankton, fish, macroinvertebrate (benthos) and loon species richness and occurrence were used to construct statistical models for lakes with varying pH, dissolved organic carbon content and lake size. pH changes, as described and predicted using the Integrated Assessment Model (Lam et al., 1998; Jeffries et al., 2000), were based on the range of emission reductions set forth in the Canada/US Air Quality Agreement (AQA). The scenarios tested include 1983, 1990, 1994 and 2010 sulphate deposition levels. Biotic models were developed for five regions in southeastern Canada (Algoma, Muskoka, and Sudbury, Ontario, southcentral Québec, and Kejimkujik, Nova Scotia) using regression tree, multiple linear regression and logistic regression analyses to make predictions about recovery after emission reductions. The analyses produced different indicator species in different regions, although some species showed consistent trends across regions. Generally, the greatest predicted recovery occurred during the final phase of emission reductions between 1994 and 2010 across all taxonomic groups and regions. The Ontario regions, on average, were predicted to recover to a greater extent than either southcentral Québec or the Kejimkujik area of Nova Scotia. Our results reconfirm that pH 5.5–6.0 is an important threshold below which damage to aquatic biota will remain a major local and regional environmental problem. This damage to biodiversity across trophic levels will persist well into the future if no further reductions in sulphate deposition are implemented.  相似文献   

18.
Nitrogen (N) pollution is a growing concern in forests of the greater Sierra Nevada, which lie downwind of the highly populated and agricultural Central Valley. Nitrogen content of Letharia vulpina tissue was analyzed from 38 sites using total Kjeldahl analysis to provide a preliminary assessment of N deposition patterns. Collections were co-located with plots where epiphytic macrolichen communities are used for estimating ammonia (NH3) deposition. Tissue N ranged from 0.6% to 2.11% with the highest values occurring in the southwestern Sierra Nevada (range: 1.38 to 2.11). Tissue N at 17 plots was elevated, as defined by a threshold concentration of 1.03%. Stepwise regression was used to determine the best predictors of tissue N from among a variety of environmental variables. The best model consisted only of longitude (r 2 = 0.64), which was reflected in the geographic distribution of tissue values: the southwestern Sierra Nevada, the high Sierras near the Tahoe Basin, and the Modoc Plateau, are three apparent N hotspots arranged along the tilted north–south axis of the study area. Withholding longitude and latitude, the best regression model suggested that NH3 estimates and annual number of wetdays interactively affect N accumulation (r 2 = 0.61; % N ∼ NH3 + wetdays + (NH3 × wetdays)). We did not expect perfect correspondence between tissue values and NH3 estimates since other N pollutants also accumulate in the lichen thallus. Additionally, other factors potentially affecting N content, such as growth rate and leaching, were not given full account.  相似文献   

19.
Pesticide applications to agricultural lands in California, USA, are reported to a central data base, while data on water and sediment quality are collected by a number of monitoring programs. Data from both sources are geo-referenced, allowing spatial analysis of relationships between pesticide application rates and the chemical and biological condition of water bodies. This study collected data from 12 watersheds, selected to represent a range of pesticide usage. Water quality parameters were measured during six surveys of stream sites receiving runoff from the selected watershed areas. This study had three objectives: to evaluate the usefulness of pesticide application data in selecting regional monitoring sites, to provide information for generating and testing hypotheses about pesticide fate and effects, and to determine whether in-stream nitrate concentration was a useful surrogate indicator for regional monitoring of toxic substances. Significant correlations were observed between pesticide application rates and in-stream pesticide concentrations (p < 0.05) and toxicity (p < 0.10). In-stream nitrate concentrations were not significantly correlated with either the amount of pesticides applied, in-stream pesticide concentrations, or in-stream toxicity (all p > 0.30). Neither total watershed area nor the area in which pesticide usage was reported correlated significantly with the amount of pesticides applied, in-stream pesticide concentrations, or in-stream toxicity (all p > 0.14). In-stream pesticide concentrations and effects were more closely related to the intensity of pesticide use than to the area under cultivation.  相似文献   

20.
With increasing interest in assessing the health or well-being ofcommunities and ecosystems, birds are being used asbioindicators. Coloniallynesting species breed mainly in coastal areas that are alsopreferred for humandevelopment, exposing the birds to various pollutants. Inthis paper concentrations of heavy metal and selenium in the feathers ofHerring Gulls(Larus argentatus) nesting in several colonies fromMassachusetts toDelaware are reported. There were significant differencesamong colonies forall metals, with metal concentrations being two to nearly fivetimes higher atsome colonies than others. Selenium showed the leastdifference, and cadmium showed the greatest difference among sites. Concentrations of lead werehighest at Pralls Island; mercury was highest at Shinnecock,Huckleberry andHarvey, and manganese was highest at Captree.  相似文献   

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