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In South Carolina between 1971 and 1975, authors evaluated the occurrence of organochlorine residues in the laughing gull (Larus atricilla), white ibis (Eudocimus albus), glossy ibis (Plegadis falcinellus), American oystercatcher (Haematopus palliatus), willet (Catoptrophorus semipalmatus), and ruddy turnstone (Arenaria interpres). Tissues of birds found dead and eggs were analyzed, eggshell thicknesses were measured, and incidental observations were made of reproductive success and population status. Eggshell thickness of the white bis, American oystercatcher, and laughing gull were not significantly different (P less than 0.05) from the pre-1947 norms. DDE and polychlorinated biphenyls (PCBs) were found most frequently and at the highest concentration in eggs. DDE residues declined significantly in oystercatcher eggs, and declined slightly in laughing gull eggs; no change was noted in white ibis eggs. No consistent trends were found for dieldrin and PCBs. Authors found no obvious problems with reproductive success of any species. Populations of the five species breeding in South Carolina appear stable. The white ibis and laughing gull in South Carolina have experienced population explosions over the past 50 years; the glossy ibis has increased substantially since the first documented breeding records in 1947.  相似文献   

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Monitoring activities were initiated in 1971 to survey the occurence and levels of organochlorine insecticide residues in bovine milk and manufactured milk products in Illinois. Dieldrin residues were the most prevalent, and were found in 96 percent of the samples. Dieldrin also accounted for the highest average residue concentration (0.09 ppm). Only 0.3% of the samples contained illegal insecticide residues. Levels of DDT and lindane were generally declining, but those for dieldrin and heptachlor epoxide tended to remain constant.  相似文献   

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We evaluated organic pollution in Bosten Lake, Xinjiang, China, by measuring the concentrations and distributions of organochlorine pesticides(OCPs) and polycyclic aromatic hydrocarbons(PAHs). Water and sediment samples were collected from 19 sites(B1–B19) in the lake for analysis. Our analytical results show that the concentrations of total OCPs in water ranges from 30.3 to 91.6 ng/L and the concentrations of PAHs ranges from undetectable(ND) to 368.7 ng/L. The concentrations of total OCPs in surface(i.e., lake bottom) sediment ranges from 6.9 to 16.7 ng/g and the concentrations of PAHs ranges from 25.2 to 491.0 ng/g. Hexachlorocyclohexanes(HCHs) and dichlorodiphenyltrichloroethanes(DDTs) account for large proportions of the OCPs. Low α- to γ-HCH ratios in both water and sediment samples indicate possible contributions from both industrial products and lindane. DDTs in water are probably from historical input, whereas DDTs in sediments are from both historical and recent inputs. Moreover, DDT products in both water and sediments were from multiple sources in the northwestern part of the lake(B11, B12, B13, and B14). Fugacity ratios for DDT isomers(p,p′-DDE and p,p′-DDT) at these sites were generally higher than equilibrium values. These results suggest that the input from the Kaidu River and diffusion of DDTs from the sediment to the water are responsible for DDT pollution in the water. Lower-molecular-weight PAHs, which originate primarily from wood and coal combustion and petroleum sources, represent the major fraction of the PAHs in both water and sediment samples. Our findings indicate that OCPs and PAHs in Bosten Lake can be attributed primarily to human activities. A risk assessment of OCPs and PAHs in water and sediment from Bosten Lake, however, suggests that concentrations are not yet high enough to cause adverse biological effects on the aquatic ecosystem.  相似文献   

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This report summarizes 1524 analyses of juvenile fish collected semiannually in 144 estuaries nationwide from July 1972 through June 1976. Pooled samples of 25 whole fish were screened for 20 common pesticides and polychlorinated biphenyls (PCBs). The three most common residues, DDT, PCBs, and dieldrin, were found in 39, 22, and 5 percent of the samples, respectively. Data indicate that estuarine pollution levels continue to decline.  相似文献   

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Levels of p,p'-DDT, p,p'-TDE, p,p'-DDE, dieldrin, polychlorinated biphenyls (PCBs), and HCB were determined in certain tissues of 31 harp seals (P hagophilus groenlandicus) taken from the Gulf of St. Lawrence during 1971 and 1973. The seals ranged in age from less than two weeks to 18 years. Mean concentrations of PCBs and sigma DDT in the various tissues were about the same sigma DDT levels were 1.64--9.88 ppm in adult seal blubber and 1.08--3.73 ppm in seal pup blubber. Organochlorine levels in harp seal samples taken in 1973 were similar to those reported by other workers for samples collected in the Gulf of St. Lawrence during 1967-71.  相似文献   

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Sediment samples were collected from a subarctic salt marsh on James Bay, Ontario in May 1976. Of 15 organochlorine compounds analyzed, trace amounts mainly of p,p-DDE and polychlorinated biphenyls (PCBs) were detected, but could not be quantitated.  相似文献   

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A preliminary tobacco pest management pesticide monitoring project was initiated in two counties of North Carolina in 1971 to develop an ecologically, economically, and socially acceptable system for protecting tobacco from damaging insect and disease pests. Results from the first year's study including sampling procedures, sample preparation, and analysis and residue data are presented in this paper.  相似文献   

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Soil samples collected during 1975 and 1976 from United States Air Force installations in California, Georgia, Ohio, Oklahoma, Texas, and Utah were analyzed for organochlorine pesticide residues. Sigma DDT, chlordane, and dieldrin were the pesticides most commonly found. In 1975, sigma DDT residues were significantly higher in samples from residential areas than in samples from golf courses or areas free of pesticide application. Chlordane residues in 1975 were significantly higher in both residential and golf course areas than in areas where pesticides had not been used. No significant differences were found in 1976 in residue levels of any pesticide monitored among various land use areas.  相似文献   

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矿物油类农药的使用现状和发展方向   总被引:6,自引:0,他引:6  
1矿物油类农药的使用现状早在1865年,即世界上第一口油井开采后的第6年,未经乳化的煤油就开始用于控制柑橘树上的介壳虫;20世纪20年代,润滑油加乳化剂开始应用于柑橘树和落叶果树,并成为果园冬季清园的主要药剂。20世纪70~80年代,碳21-碳25窄溜程喷淋油已经广泛应用在多种害虫的常年控制上。从20世纪90年代起,农用喷淋油开始使用高度精炼的白油做有效成分,使得农用喷淋油达到食品级。目前,喷淋油已在世界许多国家的蔬菜、花卉、果树和棉花等作物上使用,以控制害虫和害螨。  相似文献   

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The methyl ester of oleic acid, a plant oil derivative, can be used as an additive oil for pesticides. We compared the biodegradability in soil of this oil with that of a mineral oil by means of laboratory experiments using lysimeters of 70 cm height x 20 cm diameter. The migration in soil of the oils and of the metabolites of the plant ester over 120 days was examined by gas chromatography and liquid chromatography. The plant oil and its metabolites were completely degraded within 60 days, whereas degradation of the mineral oil required 90 days. The molecules did not migrate far into the soil and therefore presented no risk of contaminating groundwater.  相似文献   

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建立了同时测定大豆油中126种农药残留的检测方法.样品经乙腈饱和的正己烷溶解并初次除油后用正己烷饱和的乙腈萃取,于 ?5℃、20000 r/min下离心5 min,Captiva EMR-Lipid固相萃取柱净化,乙酸乙酯复溶后采用气相色谱-质谱联用仪(GC-MS/MS)多反应监测(MRM)模式检测,外标法定量.结果表...  相似文献   

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