Total DDT Residues Research Articles

Organochlorine pesticide residue in Chinese herbal medicine.

Over ten-year routine inspection results on organochlorine pesticide (OCP) residue were summarized, OCPs residues, including BHC isomers (α, β, γ, and δ-BHC), DDT analogs (p,p′-DDD, p,p′-DDE, o,p′-DDT, and p,p′-DDT), and pentachloronitrobenzene (PCNB) and its metabolites (pentachloroaniline and methyl pentachlorophenyl sulfide (MPCPS)), in 1,665 samples for 37 types of Chinese herbal medicine (CHM) using the QuEChERS method coupled with the GC-ECD. Based on the maximal residue levels for OCPs set by Asian pharmacopeias, PCNB contamination in Ginseng radix as well as the total DDT and PCNB contamination in Panacis quinquefolii radix are of concern. OCP residues in different parts of Panax ginseng were also compared. The total BHC residue in leaf and fibrous root, as well as the total DDT and PCNB residue in all parts, exceeded MRL of 0.1 mg/kg. Overall, this study provided meaningful results about OCP residue in CHM for pharmaceutical industries and consumers.

Contamination Profile of DDTs in the Shark Somniosus microcephalus from Greenland Seawaters.

DDT isomers were detected in all the liver and muscle samples of Greenland sharks Somniosus microcephalus (n = 15) caught in Greenland seawaters. The mean concentrations of ΣDDTs (sum of o,p' and p,p' DDT, DDD, and DDE isomers) were 1094 ± 818ng/g lipid weight (lw) in the muscle and 761 ± 416ng/g lw in the liver. The p,p'-DDE accounted for 48% ± 41% and 53% ± 54% of the total DDT residue in the white muscle and liver, respectively. The lipid content was 48% ± 10% in the muscle and 43% ± 17% in the liver. Female sharks showed the highest concentrations of ΣDDTs. The youngest shark showed higher concentrations of ΣDDTs in the liver than the older sharks. To our knowledge, this is one of the few investigations on DDT levels in S. microcephalus where concentrations were correlated to lipid content and sex/size.

Organochlorine pesticide residues in biological compartments of healthy mothers

The present study was conducted to detect placental and breast milk (BM) transfer of organochlorine pesticides (OCPs) between biological compartments in healthy lactating mothers. The study explores the effect of parity, breast-feeding and urban/rural residence on body burden of OCP residues. The study included 38 healthy participants submitted to cesarean delivery. Sociodemographic data and specimens of maternal and umbilical sera, adipose tissue (Adp T) and BM were collected. Specimens were analyzed to detect OCP residues. The lindane in BM, o,p'-dichlorodiphenyldichloroethane (DDD) in maternal serum (MS) and total dichlorodiphenyltrichloroethane (DDT) and o,p'-dichlorodiphenyldichloroethylene in umbilical serum were the only detected residues in significantly higher frequencies and/or means in the primigravidae than multigravidae. There was a high risk of detecting o,p'-DDD (odds ratio = 8.3) in umbilical serum of the mothers with o,p'-DDD detected in the MS. Total DDT was detected in about 65% of specimens of BM, MS and Adp T and in about 40% of the umbilical serum specimens. There was only a significant positive correlation between total DDT residues in the BM and Adp T. Total DDT residues in umbilical serum and Adp T were significantly higher in the urban than in the rural mothers. The detection of some OCPs in maternal biological compartments suggests their potential placental and BM transfer to her child during pregnancy and lactation, respectively. Furthermore, it might reflect the persistence or recent use of these pesticides in the environment.

Organochlorine Pesticides And Pcbs In Human Breast Milk

One hundred and Fifty (150) samples of human breast milk (colostrums) collected from donors patronizing a postnatal center in Nigeria were analyzed for the levels of lindane, total DDT and total PCBs residues. Donors were stratified with respect to factors that may affect accumulation of these compounds such as age, previous lactation, parity, occupation, income and education status by use of questionnaire. Analysis was performed by preliminary lipid extraction followed by partitioning on a column and finally by gas liquid chromatography equipped with an electron capture detector. Lindane, total DDT and PCBs were detected in all samples with a concentration range of 2-16 ng/ml for lindane, 28-750 ng/ml for DDT and 16-1431 ng/ml for PCBs. The mean values were 14.12 ng/ml, 186 ng/ml and 468.62 ng/ml, respectively. Correlation between levels of pesticides concentrated and the following parameters of age, parity and occupation were not significant. Comparison of the mean results from this study with the levels obtained from other studies in the more industrialized regions of the world showed that the residue levels in human milk in this location in Nigeria is higher than the world's average, while it is several factors less than the average obtained from some African countries. IFE Journal of Science Vol. 9 (2) 2007 pp. 219-224

Dichlorodiphenyltrichloroethane (DDT) and its metabolites in dairy milk and milk products of Agra City, India

bovine milk, milk products and in the environmental samples has been reported. Therefore, a study was undertaken to monitor the trace levels of DDT and its metabolites in dairy milk and butter samples of Agra city, India to assess the risk to the consumers and seasonal variability. Analysis of DDT from milk and butter samples were done by using the method standardized in the laboratory. During the year 2002-2003 milk samples were collected for the analysis of DDT and its metabolites in different seasons viz. winter, summer and rainy season. During winter seasons 28 samples of milk were analyzed and only 19 samples were found to be positive with the o, p-DDT, p, p-DDT and p, p-DDE metabolites of DDT while in summer and rainy seasons only 15 and 20 were found positive from out of 28 and 27 samples. The total DDT (o, p-DDT, +p, p-DDT+p, p-DDE) residues were 36.8 9, 33.2 9, 23.9x10 9 during winter, summer and rainy seasons, respectively. In the present study, during 2002-2003 out of 83 dairy milk samples only 54 (65.10%) were found to be positive with DDT residues. Similarly, out of 21, 20 and 19 butter samples, 13, 12 and 12 samples were positive with DDT residues. The total DDT residue concentrations were 26.1  10 9, 23.8 10 -9 and 22.4 10 -9 during winter, summer and rainy seasons, respectively. Tolerance limit for the DDT residues in milk and butter samples is 0.05x10 "6 (on whole milk basis) and 1.25 -6 prescribed by prevention of food adulteration, India (PFA, 1986). None of the milk and butter samples showed total DDT residues above are higher than the tolerance limit. The total DDT concentrations were 36.8 9, 33.2x 10 -9 and 23.9x 10 -9 in winter summer and rainy seasons, respectively while the same pattern of residues was observed in butter samples. Maximum permissible intake (MPI) and theoretical maximum residue contribution (TMRC) were calculated for DDT in milk and butter. These values also indicated that milk and butter are safe for consumption.

Comparison of Gas Chromatography and Immunoassay Methods for Analysis of Total DDT in Calcareous Soils

Three different calcareous soil samples from Lebanon were analyzed for total DDT pesticide residue using GC and ELISA methods. Two experiments were conducted on three different calcareous soil samples. In each experiment, triplicates of 5 gm soil samples were each fortified with standard solutions of DDE to reach concentrations of 0, 5, 25, 50, 100 and 200 ng g− 1 and allowed to equilibrate at room temperature for 6 hours. Each sample was then extracted with 25 mL of 90% methanol by shaking in glass bottles on a mechanical shaker for 16 hours. The bottles were allowed to stand for 30 minutes and aliquots were taken from the clear supernatant for analyses without further cleanup. The total DDT in the extract was measured in triplicate by GC and ELISA. The results indicated that the two methods were highly correlated (R = 0.955–0.994). Differences in soil properties did not affect the accuracy of the detection limits of ELISA. Immunoassay technique can be used for rapid and accurate measurement of total DDT residues in mineral calcareous soils in Lebanon.

Effect of Ras cheese manufacturing on the stability of DDT and its metabolites

Residue levels of DDT were analyzed in 25 samples of liquid milk as well as 25 samples of Ras cheese collected from different regions in Great Cairo Governorates. Levels of DDT and its metabolites in liquid milk samples were higher than those in Ras cheese. The detected levels of pesticides in milk and cheese were lower than the maximum acceptable limits (MAL s) recommended by FAO/WHO (1993). The reduction levels of total DDT in Ras cheese made from contaminated milk with different levels of DDT (0.1, 1.0 and 10.0 mg/kg fat) were 40.6, 33.9 and 25.5%, respectively, at the end of storage period. The isolated Ras cheese microorganisms reduced the total DDT residues by 10.8, 11.8 and 4.8% for Streptococci, lactobacilli and yeasts, respectively, at the end of incubation period.

Polychlorinated biphenyls and organochlorine pesticides in EELS ( Anguilla anguilla L.) from Welsh rivers

Organochlorine concentrations in the muscle tissues of eels at 41 freshwater sites across Wales were surveyed in 1993. Positive but weak relationships were detected between eel age or length and the concentration of some organochlorines. Isomers of HCH were below detection at most sites. Dieldrin was widespread at 10–100 μg kt −1 wet weight, despite its ban in sheep dip in 1989. Total DDT residue concentrations averaged 73 μg kg −1. Total PCB burdens expressed as Arochlor 1260, were > 50 μg kg −1 at 76% of sites and > 100 μg kg −1 at 46% of sites. The range of concentrations was comparable with other UK data. Rural sites had relatively low levels of PCBs, highest contamination occurring in the lower reaches of industrialised catchments. The inferences for environmental effects are discussed.

DDT Persistence and Volatility as Affected by Management Practices after 23 Years

AbstractIn 1971, an experiment was conducted in a field containing high amounts of residual DDT (dichlorodiphenyltrichloroethane) to evaluate deep plowing, followed by flooding, with and without organic matter applications, as soil and water management tools to reduce total DDT residues and preferentially degrade the residual DDT to DDD [1,1‐dichloro‐2,2‐bis (p‐chlorophenyl) ethane]. The experimental site was revisited in 1994 to determine residual soil concentrations of DDT isomers and their metabolites in soil, soil dust, and the atmosphere. Also, volatilization flux measurements were made to evaluate rates of movement into the atmosphere. Soil concentrations of all DDT isomers and metabolites had decreased in all plots, with p,p′‐DDE[1,1‐dichloro‐2,2‐bis (p‐chlorophenyl) ethylene] the major component of the total remaining residues (DDTR). The total DDTR residues in the surface 75 cm varied from 10 to 28% of their amounts in 1971. The highest concentrations were found in the deep plowed, unflooded plots with DDTR decreasing from 4 mg kg−1 at 0 to15 cm to 0.3 mg kg−1 at 60 to 75 cm. Deep plowing evidently increased DDT persistence by placing it deeper into the soil profile, which protected it from degradation and volatilization. Concentrations of all isomers were lower in the previously flooded plots. Degrading DDT under reducing conditions brought about by flooding lessened or prevented the formation of DDE in the soil thus ultimately reducing its redistribution into the environment. Significant concentrations of both o,p′ and p,p′‐DDE and DDT were detected in the atmosphere above the plots. Measurable volatilization fluxes were observed over 48‐h periods in February and September. Irrigating the soil with 20 mm water dramatically increased the volatilization flux of all the DDT isomers and metabolites, particularly p,p′‐DDE. The finding that DDT isomers continue to volatilize from the soil surface has implications for long‐range transport of DDT and contaminating forage or foodstuff. The possible health implications from exposure to humans or animals through the air route is unknown.

Influence of Agricultural Practices on the Levels of DDT and Its Residues in Soil

DDT residues in soils resulting from past applications of DDT to pasture are of concern due to the uptake and accumulation of these residues by stock. In this paper, we report the results of a study of DDT residues in the soil (Lismore stoney silt loam) of long-term irrigation and superphosphate application trials set up approximately 40 years ago. Irrigation at a rate sufficient to maintain mean moisture in the top 100 mm of soil during the summer at 27.3% resulted in a total DDT residue level of around 40% that of unirrigated soil (mean summer moisture=13.8%). Superphosphate treatment resulted in lower soil level of p,p'-DDT and total DDT residues compared to the unfertilized control. Possible causes of these effects are discussed.

Spatial and Temporal Trends of Organochlorine Contaminants in Spottail Shiners from Selected Sites in the Great Lakes (1975-1990)

This article reports on organochlorine contaminant bioavailability and temporal trends in nearshore waters of the Great Lakes. Collections of young-of-the-year spottail shiners ( Notropis hudsonius) were used as biomonitors of contaminants. Guidelines and criteria adopted for the protection of wildlife were used to assess the importance of contaminant accumulations in spottail shiners. Of the 10 compounds analyzed, only PCB and mirex concentrations in spottail shiners exceeded Aquatic Life Guidelines. Fifteen of 37 (41%) sites sampled in 1990 had shiners with PCB concentrations over the guideline. Mirex was only found in fish from the Niagara River, the Credit River in western Lake Ontario, and the St. Lawrence River at Cornwall. Total PCB and DDT residues in fish collected in 1990 were significantly (p<0.05) lower than residues in fish from the 1970s. While PCB and DDT residues continued to decline at most sites, downward trends at some sites have stabilized.

Present Status and Temporal Trends of Organochlorine Contaminants in Young-of-the-Year Spottail Shiner (Notropis hudsonius) from Lake Ontario

Contaminant residue data from Ontario nearshore collections of young-of-the-year spottail shiner (Notropis hudsonius) were used to assess present status and temporal trends of bioavailable organochlorine contaminants in Lake Ontario. PCB residues in spottail shiners were in excess of the International Joint Commission Aquatic Life Guideline at 11 of the 14 sites sampled in 1987; mirex residues exceeded the Guideline at 7 of the 14 sites sampled. PCB and total DDT residues in the recent shiner collections were significantly (p &lt; 0.01) lower relative to residue levels in collections in the 1970's. However, residue declines have slowed during the 1980's. Thus, PCB residues in spottail shiners declined by 69% over a 5-yr interval (1975–80) whereas residues declined only by 17% at the same sites during the following 7-yr interval (1980–87). Residues of hexachlorobenzene, heptachlor, aldrin, total hexachlorocyclohexane, octachlorostyrene, total chlordane, and toxaphene were generally near their detection limits in all shiner collections. A Forage Fish Contaminant Index was established for the purpose of ranking the collection sites in relative order of contamination to assess the need for point-source investigations.

Gas Liquid Chromatographic Analysis of DDT Residues in the Kidney of Labeo rohita

AbstractLaboratory acclimated Labeo rohita, common fresh water edible fish, were exposed to a sublethal concentration (2.5 ppm) of DDT for 2, 4, 8, 16 and 32 days. Residues of three isomers of DDT were estimated in the kidney of Labeo rohita using the gas liquid chromatographic technique. The maximum residues of DDT, DDE and DDD were 1.4327, 0.4172 and 0.2913 ppm, respectively. The total DDT residues concentration was 2.1412 ppm on the final day of the experiment. The tabulated tcalculated t at all intervals.

Accumulation of DDT Residues in the Testes of Channa punctatus (Bloch): A Gas Liquid Chromatographic Analysis

Residues of DDT isomers accumulated in the testes of Channa punctatus (BLOCH) were quantitatively estimated by exposing the fish to 2.5 ppm sublethal concentration for 32 days. The study revealed a high accumulation of DDT residues in the testes. The maximum concentration of residues was noted on the 32nd day of the experiment. The DDT isomer accumulated in maximum concentrations was followed by DDE and DDD isomers. The maximum residue concentrations were 0.3221 ppm (DDT), 0.1119 ppm (DDE) and 0.0695 ppm (DDD) on the 32nd day of the experiment. The total DDT residue concentration at the final interval was 0.563 ppm.

Organochlorine residues in water from the Mahala water reservoir, Jaipur, India

Residues of p, p′-DDE, p, p′-DDT α-, β-, γ-isomers of HCH, aldrin and heptachlor in water, from four different sites of the Mahala water reservoir were monitored periodically from September 1985 to October 1987. All the samples contained the above residues in varying concentrations. Isomers of HCH predominated and were followed in relative dominance by aldrin, total DDT and heptachlor residues, p, p′-DDE and p, p′-DDD constituted the major fraction of total p, p′-DDT. Monthly total organochlorine residue levels in water ranged between 1·07 and 81·23 μg litre −1 . The variation is attributed to the run-off or subsoil water movement from the catchment area.

National contaminant biomonitoring program: Residues of organochlorine chemicals in U.S. Freshwater Fish, 1976?1984

The U.S. Fish and Wildlife Service periodically determines concentrations of organochlorine chemicals in freshwater fish collected from a nationwide network of stations as part of the National Contaminant Biomonitoring Program (NCBP, formerly a part of the National Pesticide Monitoring Program). From late 1984 to early 1985, a total of 321 composite fish samples were collected from 112 stations and analyzed for organochlorine chemical residues. The mean concentrations of total DDT did not change from 1980-81 to 1984, following a period of steady decline through the 1970's; however, the mean concentrations ofp,p'-DDT declined significantly. The most persistent DDT homolog (p,p'-DDE) was detected at 98% of the stations sampled in 1984, and constituted 73% of total DDT residues, up from 70% in 1974-79. Collectively, these findings indicate a low rate of influx and continued weathering of DDT in the environment. Residues of polychlorinated biphenyls (PCBs) also remained widespread, but a significant downward trend in total PCBs was evident, and early eluting PCB components were present at fewer stations than in the past. Mean concentrations of dieldrin have not changed since 1978-79; concentrations remained highest in Hawaii and in the Great Lakes. Toxaphene concentrations declined from 1980-81 to 1984, especially in the Great Lakes, and the incidence of toxaphene declined from 88% of the stations sampled in 1980-81 to 69% in 1984. Mean chordane concentrations did not change from 1980-81 to 1984, following a period of decline; however,trans-nonachlor replacedcis-chlordane as the most abundant component, suggesting a lower influx of chlordane to the aquatic environment. Residues of other organochlorines-mirex, pentachloroanisole (PCA), benzene hexachloride (BHC) isomers, endrin, heptachlor, hexachlorobenzene (HCB), and Dacthal(®) (DCPA)-were either found at relatively few (<25%) of the stations sampled in 1984 or were characterized by relatively low concentrations. In general, organochlorine concentrations were lower in 1984 than at any time reported previously.

Residues of DDT and dieldrin in the subcutaneous fat and butterfat of cattle

Technical DDT or dieldrin was added to crushed wheat and fed to steers and dairy cows. Subcutaneous fat collected by biopsy and butterfat were examined for residues of DDT, DDD, DDE and dieldrin. Steers fed 6, 36 or 216 mg DDT/day for 10 weeks had total DDT residues (mean � s.e.) in subcutaneous fat of 0.38� 0.01, 2.72�0.37 and 24.5�6.9 mg/kg respectively. DDD was the major residue, comprising 80% of the total. When DDT was withdrawn from the diet, residues declined. Half-life for DDT was 11 weeks (range 8-14), and for DDD was 5 weeks (range 3.5-7.4). Half-life could not be determined for DDE. Steers fed 36 mg dieldrin/day for 10 weeks had 17.3�4.9 mg/kg dieldrin in the subcutaneous fat. The half-life for dieldrin was 5 weeks (range 2.5-10.0). Dairy cows fed 6, 36 or 216 mg DDT/day for 6 weeks had total DDT residues in butterfat of 0.31�0.05, 2.5�0.60 and 20.8�1.2 mg/kg respectively. DDD was again the major residue, comprising 65% of total residues. Half-lives of DDT, DDD and DDE in butterfat were 7.2 (range 6.3-7.7), 3 (range 2.2-3.0) and 5 weeks (range 3.5-8.0) respectively. When 36 mg dieldrin was fed to dairy cows for 6 weeks, residues of 17.3�4.6 mg/kg were found in the butterfat. The half-life for dieldrin in butterfat was 9 weeks (range 6-11.5).

Reproductive impairment in a fish inhabiting a contaminated coastal environment off Southern California.

White croaker (Genyonemus lineatus), collected from a highly contaminated site in San Pedro Bay and from a reference site 80 km away (Dana Point), were induced to spawn in the laboratory. Forty-one per cent of San Pedro Bay females and 54% of Dana Point females spawned. Examination of the ovaries of non-spwaning females revealed that spawning was imminent in the remainder of Dana Point fish but only in 16% of the San Pedro Bay fish. The remainder of the San Pedro Bay fish (43%) contained only immature, yolky oocytes. No croakers containing more than 3.8 ppm ovarian total DDT could be induced to spawn whereas 36% of a contemporaneous San Pedro Bay sample had ovarian total DDT residues in excess of 4 ppm. This suggests that the inability to induce spawning in white croaker may be associated with an ovarian total DDT threshold of about 4 ppm. These data, coupled with observed decreases in fecundity (32%), fertility (14%), and early oocyte loss (30%) relative to reference fish, could partially explain the population declines observed for many southern California fishes since the 1940s.

Variations in DDE percentage correlated with total DDT burden in the blubber of fin and sei whales

Total DDT burden and DDE percentage (DDE/DDT+TDE+DDE) in the blubber of fin and sei whales are highly correlated. Total DDT concentration may be an important source of variation for the DDE percentage detected in different individuals of the same population. Such a positive correlation is explained by the intensification of the dehydrochlorinative and differential excretive functions at higher pollutant levels. In the past, variations in the DDE percentage have been attributed to differences in the chronology of DDT input into the ecosystem and assumed to be indicators of population discreteness or changes in the pattern of DDT exposure of a given population. However, changes in the DDE percentage as related to total DDT burden may be important within the observed normal ranges of variation of total DDT residue levels caused by age and sex composition of the population. Therefore, the DDE percentage may be reliably used only when full control of the life history parameters of the sample is achieved and when strict homogeneity among the samples to be compared has been proved.

Organochloride insecticide residues in air in Delhi, India

Regular monitoring of air at three different sites, namely, Netaji Nagar, Moti Nagar and Town Hall in the metropolitan city of Delhi, India from June, 1980 to May, 1982 revealed varying levels of residues of DDT and HCH. The concentration of total DDT residues varied from 4 to 232 ng m−3 with an average of 60 ng m−3. Total HCH ranged from 0 to 21797 ng m−3 with an average of 438 ng m−3. Comparatively higher levels of total DDT (73 ng M−3) were detected at Moti Nagar, the site near a DDT factory. The total HCH was highest at Town Hall (931 ng m−3). Normally, higher quantities of the residues of DDT and HCH were detected during October to December. The insecticide residues consisted mainly of p, p′-DDT, p, p′-DDE, o, p′-DDT and p, p′-DDD, α- and γ-HCH. Only p, p′-DDT and p, p′-DDE were detected in all the samples and accounted for the bulk of total DDT. The HCH residues were mainly due to the α-isomer. Generally the concentration of HCH was higher than DDT in the air samples collected during the survey.