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1.
Organochlorine pesticide analyses were performed on human milk samples obtained from 34 women living in the Mississippi Delta, a high pesticide usage area, and from six women living in Starkville, Mississippi, a low pesticide usage area. Nine women collected samples before and after their babies had nursed so that fat levels and sigma DDT levels could be compared on whole milk and milk fat bases. sigma DDT values were independent of collection time if calculated on a milk fat basis, but not if calculated on a whole milk basis. Thus, the most consistent indicator of DDT residues were values calculated on a milk fat basis. Residue levels for p,p'-DDE, p,p'-DDT, and sigma DDT were significantly different (P less than 0.01) in samples from the two areas. Residues of o,p'-DDT, beta-BHC, and oxychlordane in milk samples from women living in the high pesticide usage area also were significantly different (P less than 0.05). A mean value of 19.17 ppm sigma DDT, found in the milk fat of samples from the high pesticide usage area, is the highest ever reported. Samples from the low pesticide usage area contained a mean level of 2.36 ppm sigma DDT.  相似文献   

2.
Residue data from the 1972 (FY--73) National Soils Monitoring Program are summarized. Composite samples of agricultural soil and mature crops were collected from 1,483 of the 1,533 selected 4-hectare sites in 37 states. Analyses were performed for organochlorine and organophosphorus compounds, trifluralin and polychlorinated biphenyls (PCBs); analysis for atrazine was performed only when pesticide application data indicated current-year use. Organochlorine pesticides were detected in 45 percent of the soil samples. The most frequently detected compound was dieldrin, found in 27 percent of all soil samples. Other compounds detected, in order of frequency, included DDT, aldrin, chlordane, and heptachlor epoxide, found, respectively, in 21, 9, 8, and 7 percent of all soil samples. Crop samples were collected from 727 sites. All were analyzed for organochlorines; analyses were performed for organophosphates and atrazine only when pesticide application data indicated current-year use. For all crops, 40 percent of the samples contained detectable levels of organochlorines and 10 percent contained detectable levels of organophosphates. Atrazine was not detected.  相似文献   

3.
Chlorinated hydrocarbon pesticide burdens, especially those of DDT and its metabolites, have been determined for 19 species of small terrestrial migratory birds killed chiefly at Florida television towers from 1964 to 1973. All 128 samples were sorted into pools by species. All pooled samples except one contained DDE and often DDT and DDD; dieldrin was present in 60 of the samples; but no PCB's were detected. In small subsamples, sigma DDT (p,p'-DDT, p,p'-DDD, and p,p'-DDE) residues sometimes differed between males and females, adults and immatures, and northbound and southbound migrants but results of these comparisons were inconclusive. Sigma DDT burdens were highest in adipose tissue and much lower in liver and brain samples. Especially among birds taken since 1970 have the pesticide levels in adipose tissue been at low levels, generally less than 3 ppm sigma DDT. These low quantities are comparable to those quoted in other reports on birds of similar trophic levels. The insectivorous and/or partly granivorous birds feeding on or near the ground tended to have higher sigma DDT levels than did the more arboreal species.  相似文献   

4.
Surveys to identify virus diseases affecting garlic ( Allium sativum ), onion ( Allium cepa ) and Persian leek ( Allium ampeloprasum var. persicum ) were conducted from 1999 to 2002. Surveys covered different regions of Iran (Tehran [different vegetable markets, farmer fields and cultivation areas], Noushahr, Chalous, Roudbar, Sari, Hamadan, Touyserkan, Ghazvin and Jiroft). A total of 2045 (1285 garlic, 525 onion and 230 leek) samples showing symptoms of virus infection were collected and tested by ELISA; and in some cases tests were also confirmed by immunoelectron microscopy (IEM) for the presence of Allium viruses. ELISA results showed that the following viruses were detected: Onion yellow dwarf virus (OYDV), Leek yellow stripe virus (LYSV) (genus Potyvirus , family Potyviridae ), Garlic common latent virus (GarCLV), Shallot latent virus (SLV) (genus Carlavirus ), Garlic virus D (GarV-D), Garlic virus B (GarV-B) and Garlic virus C type (GarV-C) (genus Allexivirus ). None of the samples reacted with antibodies to Shallot yellow stripe virus (SYSV) genus Potyvirus , family Potyviridae ), Shallot virus X (ShVX) and Garlic virus A (GarV-A, genus Allexivirus ). GarCLV, SLV, GarV-D, GarV-B and GarV-C are reported for the first time from Allium crops in Iran.  相似文献   

5.
A resistance management programme comparing rotations, mosaics and single use of insecticides for residual house-spraying against the insect vectors of malaria is being carried out in Southern Mexico. The area was chosen because of its prior history of insecticide use, relatively sedentary vector, and physical features of the area which limit inward migration of insects to the study area. A high level of resistance to DDT and low levels of organophosphorus (OP), carbamate and pyrethroid resistance were detected by WHO discriminating-dose assays in field populations of Anopheles albimanus in the pre-spray period in the region where this resistance management project is being undertaken. After the first year of spraying, resistance, as measured by a discriminating-dose assay, was still at a high level for DDT and had risen for all the other insecticides. Biochemical assays showed that DDT resistance was primarily caused by elevated levels of glutathione S-transferase (GST) activity leading to increased rates of metabolism of DDT to DDE. The numbers of individuals with elevated GST and DDT resistance were well correlated, suggesting that this is the only major DDT resistance mechanism in this population. The carbamate resistance in this population was conferred by an altered acetylcholinesterase (AChE) mechanism. The level of resistance in bioassays correlated well with the frequency of individuals homozygous for the altered AChE allele. This suggests that the level of resistance conferred by this mechanism in its heterozygous state is below the level of detection of the bioassay. The low levels of OP and pyrethroid resistance could be conferred by either the elevated esterase or monooxygenase enzymes. The esterases, however, are elevated only with p-nitrophenyl acetate (PNPA), and are unlikely to be causing broad-spectrum OP resistance. The altered AChE mechanism may also be contributing to the OP but not the pyrethroid resistance. There were significant differences in some resistance gene frequencies for insects obtained by different indoor and outdoor trapping methods. To determine whether the different sampling methods were effectively sampling the same interbreeding population, RAPD analysis of insects obtained by different collection methods in different villages was undertaken. There was no observed variability in the RAPD patterns for the different mosquito samples with a number of primers. ©1997 SCI  相似文献   

6.
sigma DDT residues in the St. Lucie River bottom sediments increased after Lake Okeechobee water was discharged through the St. Lucie Canal into the area. sigma DDT levels were highest in sediment samples from the Palm City area, ranging from 1.8 ppb to 6.15 ppb. Sediment samples from the A1A Highway Bridge area contained 1.6-6.8 ppb Aroclor 1254. Levels of polychlorinated biphenyls (PCBs) and sigma DDT in sediment samples from the junction of the St. Lucie and Indian Rivers were not detectable. Surface water samples from the estuary did not show any detectable DDT or PCB residues.  相似文献   

7.
More than a half million pounds of DDT were applied to control mosquitoes in salt marsh estuaries of Cape May County, New Jersey, from 1946 to 1966. The use of DDT was discontinued in the County after 1966. In 1967, mean concentrations of DDT and metabolites ranged from 0.63 to 9.05 ppm in aquatic fauna, but by 1973 mean residue levels had decreased 84 to 99 percent among nine species. DDE was still present at reduced levels in nearly all samples in 1973, but other DDT isomers had mostly disappeared. Dieldrin was detected only in clapper rails, and residue levels decreased during the period. Mean concentrations of PCB's increased in the clapper rail, remained the same in the fiddler crab and mud snail, and decreased in the sheepshead minnow, mummichog, striped killifish, and salt marsh snail. Small amounts of mirex, toxaphene, cis-chlordane (and/or trans-nonachlor), oxychlordane, and HCB were detected in a few specimens.  相似文献   

8.
Residues of DDT were detected in 76 of 101 samples of rainwater collected during spring and summer at several sites in the Province of New Brunswick in 1967 and 1968, and at one site in the Magdalen Islands, Quebec, in 1968. The dominant residue was p,p'-DDT. Levels of DDT and metabolites combined ranged from less than 0.01 to 1.33 microgram/kg. Levels of DDT and metabolites in the pollen of four species of forest trees in New Brunswick ranged from 0.544 to 1.01 mg/kg; such contaminated pollen possibly contributed to residues in rainwater. Residue data for rainwater from two sites were used to estimate the amount of DDT aerially transported into the Gulf of St. Lawrence during July to October 1968.  相似文献   

9.
In Iran, the tomato growing area is about 150 000 ha, mostly located in the south of the country. The Iranian Plant Protection Organization and inspection service in Iranian Research Institute of Plant Protection (IRIPP) prepared a monitoring program for this pest in 2009 and 2010. A technical guideline was issued and distributed among PPO inspectors. For the first time in November 2010, samples were collected by Uromiyeh PPO on tomato from Uromiyeh in Azarbaijan province in North West Iran. The specimens found in these samples were identified as Tuta absoluta. Three months later in January 2011, pheromone traps were placed in tomato growing areas in Borazjan, Busher province, to detect and monitor this pest. T. absoluta was identified, based on adult morphology and on male genitalia from moths collected in 5 of these traps during January 2011. More pheromone traps were put into place covering the entire tomato growing area throughout the country. As of June 2011, the pest was detected in 24 different locations. This is the first report of T. absoluta in Iran. T. absoluta is a very serious pest for tomato, and an outbreak of this pest is expected during the crop cycle in autumn and winter 2011–2012 in the south of Iran. Thus, based on experiences in other countries an IPM program according to available tools and materials was developed.  相似文献   

10.
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   

11.
Pacific oysters (Crassostrea gigas Thunberg) from 19 sites in Tasmania were surveyed for pesticide residues. All samples were analyzed for dieldrin and DDT, and five samples were analyzed for hexachlorobenzene (HCB) and lindane. Only DDT was found in all samples. Dieldrin levels were high in oysters from the Tamar River, but were highest (0.39 mg/kg wet weight) in samples from Ruffin's Bay. In contrast, other residue levels were low. Distribution of pesticides in Tamar River samples differed: dieldrin could be correlated with industrial uses upstream and DDT could be correlated with low-level widespread agricultural use.  相似文献   

12.
Muscle, liver, brain, and abdominal body fat samples of goats, buffalo, and chickens, all common meat sources in India, were analyzed by gas-liquid chromatography (GLC) for residues of DDT and benzene hexachloride (BHC). A few samples of goat and buffalo bone marrow were also included. Relatively high residue levels were found in body fat and bone marrow compared with other tissues. DDT and BHC residue levels were highest in chicken body fat, averaging 4.157 ppm sigma DDT and 3.879 ppm BHC. DDT content was much higher in goat and buffalo bone marrow than in the corresponding body fat. DDT levels in brain samples were highest (0.138 ppm) in buffalo. p,p'-TDE levels were higher than p,p'-DDE levels in buffalo; overall DDT levels were lowest in goats. BHC residues were generally low in buffalo; alpha-BHC accounted for most BHC residues in brain tissues. Greater accumulations of DDT and BHC were found in leg muscles than in breast muscles of chickens.  相似文献   

13.
Over the period 1968/70 147 samples of raspberries and 124 samples of strawberries were analysed for organochlorine insecticide residues. DDT was found in 30% of the samples but only one sample contained as much as 1.4 parts/million. No residues were detected in the raspberries during the last year of the survey which coincided with the discontinued use of DDT on this crop. 184 of the above samples were also analysed for residues of organophosphorus insecticides and the fungicide dichlofluanid. Malathion was found in one sample of raspberries. Approximately 40% of the strawberries contained detectable amounts of dichlofluanid and its metabolite with combined residues ranging from 0.1 to 7.5 parts/million. Only two samples of raspberries contained residues of either dichlofluanid or its metabolite. It is considered that the residues of these various pesticides should not present a hazard to consumers.  相似文献   

14.
BACKGROUND: Phelebotumus papatsi is considered to be the main vector of zoonotic cutaneous leishmaniasis as well as sand fly fever in Iran. There are several measures for vector control, with emphasis on insecticides. The objective of this study was to determine the baseline susceptibility of this vector to the commonly used insecticides in an endemic focus of the disease in central Iran. P. papatasi collected from the field were used for susceptibility status. Its baseline susceptibility to DDT and pyrethroids was assessed on about 6866 specimens collected from Badrood rural district, Esfahan Province, Iran, during the summer of 2010. The LT50 and LT90 values were measured according to the World Health Organisation (WHO) test using probit analysis and regression lines. RESULTS: Results of tests against female P. papatasi revealed LT50 values to DDT 4%, permethrin 0.75%, deltamethrin 0.1%, cyfluthrin 0.15% and lambdacyhalothrin 0.05% of 1104.97, 182.35, 26.79, 15.42 and 1.48 s respectively. The figures for male P. papatasi were 973.51, 59.5, 4.4, 2.65 and 1.5. CONCLUSION: The results of this study provide a guideline for implementation of different vector control measures. Furthermore, guidelines are needed for monitoring and evaluation of insecticide susceptibility tests against sand flies. Copyright © 2012 Society of Chemical Industry  相似文献   

15.
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   

16.
The susceptibility to pyrethroid, organochlorine, organophosphorus and carbamate insecticides, of 20 strains of houseflies (Musca domestica L.) collected in the Middle East and North Africa, was assessed by topical application. No resistance to pyrethroids was found but most flies were resistant to DDT, gamma-HCH, organophosphorus and carbamate insecticides. Numerical factors of resistance for a susceptible and two different resistant strains, obtained using different bioassay techniques, were compared. High mortality (≥95%) was achieved with ‘resisted’ insecticides in tests with space sprays, but only low, variable mortality resulted from deposit tests. If this occurs under practical field conditions, moderately resistant populations of flies could be controlled by using space sprays containing comparatively high concentrations of active ingredient, but increased levels of deposit would be ineffective.  相似文献   

17.
Organochlorine residues in wings of adult mallards (Anas platyrhynchos) and black ducks (Anas rubripes) were monitored nationwide from birds harvested during the 1979-80 hunting season. DDE residues were found in all samples. DDT residues had declined from levels reported in 1976 on a flyway basis but the decline was significant (P less than 0.05) only in the Pacific Flyway. Levels of DDT, DDE, TDE, and dieldrin were low on a flyway basis, and all but DDE declined significantly (P less than 0.05) in the percent occurrence. Polychlorinated biphenyls (PCB) levels were lower in mallard wings from all flyways compared with 1976 data, but percent occurrence had significantly (P less than 0.05) increased. Pools from Alabama and New Mexico continued to show higher DDE residues than pools from other areas.  相似文献   

18.
Results are presented for the determination of organochlorine insecticide residues in grain, pulses and nuts sampled on arrival in Britain during the 2½ years up to June 1969. BHC was detected in nearly every sample but the general level was low, most samples containing less than 0·1 ppm. DDT was found less frequently. Very few samples contained more than 1 ppm of either insecticide. DDE in trace amounts was found in about 10% of the samples of grain and nuts and TDE was found in one sample of grain. The only other organochlorine compounds detected were aldrin in one sample of pulses and hexachlorobenzene in 7 samples of wheat.  相似文献   

19.
The 10-5 bait formulation of mirex insecticide was applied to a 20,000-acre area of northeast Florida. For 24 months after application, samples of a wide variety of fauna were collected and analyzed for mirex content. Insects accumulated mirex to the greatest extent in the first 6 months after application; most residues had decreased greatly by 12 months. Other invertebrates showed low mirex levels during the first 9 months after application and none after 12 months. Fish possessed low levels of insecticides for 9 months; amphibians showed mirex residues for 12 months after application. In general, reptiles had low levels throughout the 24-month period and mammals had higher levels, particularly in fat tissues. Birds consistently had low to moderate mirex levels. After a single application of 10-5 mirex bait, only relatively low levels of insecticide were detected in exposed fauna. After 24-months, mirex was found infrequently and at low levels.  相似文献   

20.
As part of the National Pesticide Monitoring Program, the U.S. Fish and Wildlife Service analyzed organochlorine contaminant residues in fish samples collected from about 100 stations each year from 1970 to 1974. During this period, mean residues of DDT and its metabolites declined nationally but remained widespread, and high concentrations continued to be present in areas where DDT use was extensive. Results of interlaboratory crosscheck analyses supported these conclusions, despite interpretation problems posed by intercompound analytical interferences in 1970 and 1971. Temporal trends in PCB residues were less obvious. Highest PCB residues were found in the industrialized areas of the Northwest and Midwest, and traces were present at most stations. Dieldrin and endrin residues remained essentially unchanged during this period; dieldrin residues were widespread and were highest in Hawaii and in areas of the Midwest where aldrin was used extensively. Toxaphene occurrence increased; it was formerly found only in fish from streams draining cotton-farming regions, but residues were detected in 1974 samples from other areas. According to the recommendation of the National Academy of Sciences' Water Quality Criteria, organochlorine residues in freshwater fish may have represented a hazard to piscivorous fish and wildlife at 71 percent of the stations sampled in 1970 and 66 percent in 1974.  相似文献   

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