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At least 973 records · Page 54Linked to original sources
PubMed1998

Concentrations and spatial variations of cyclodienes and other organochlorines in herring and perch from the Baltic Sea.

Herring (Clupea harengus) and perch (Perca fluviatilis) were collected in the northern and southern Baltic Sea and analyzed for the presence of the cyclodiene pesticides chlordane (CHL), heptachlor, aldrin, dieldrin, endrin, isodrin, endosulfan and mirex, as well as other organochlorine contaminants, hexachlorocyclohexanes (HCHs), DDTs, hexachlorobenzene (HCBz) and polychlorinated biphenyls (PCBs) in order to investigate concentrations, accumulation and differences in geographical distribution. In the northern part of the Baltic Sea, Gulf of Bothnia, herring were collected at two pelagic stations, one in the Bothnian Bay (BB) and the other in the Bothnian Sea (BS), respectively; perch were collected at four coastal locations along the Swedish coast. All these locations were selected to represent background areas except one in the vicinity of an industrialised and contaminated area. Both specimens were also caught in the southern part of the Baltic Sea, in the Gulf of Gdansk (GG), Poland, a potentially highly polluted area. From the eight cyclodiene pesticides analyzed, three were detected in herring and perch samples, including 12 different CHL-related compounds, dieldrin and mirex. To our knowledge, it is the first time that mirex has been detected in samples from the Baltic Sea. Neither heptachlor, aldrin, endrin, isodrin nor endosulfan were found. However, HCHs, DDTs, HCBz and PCBs were found in every sample investigated, and the concentrations ranged e.g. for the cyclodiene chemicals dieldrin and CHL-related compounds from 30 to 170 ng/g lipid and for PCBs from 360 to 5400 ng/g lipid, both fish species included. Differences in contamination burden between the sites can be seen, e.g. for herring the BB and GG locals were similar, and generally lower than BS for all chemicals except that of DDT where GG was the highest. For the perch samples the industrialised location had markedly higher concentrations of HCBz and PCBs than the other locations. This species also identifies GG as the most DDT contaminated site among the three studied areas.

Animals↗
PubMed2000

Organochlorines in Greenland lake sediments and landlocked Arctic char (Salvelinus alpinus).

Lake sediments and landlocked Arctic char (Salvelinus alpinus) were sampled in 1994 and 1995 at four different locations in Greenland, three at the west coast and one at the east coast. Sediments, char muscle and char liver were analysed for PCBs (10 congeners), DDTs (pp'), HCHs (alpha, beta, gamma), dieldrin, HCB and chlordanes (5) and char in addition to toxaphene (total and 4 congeners). All organochlorines in the sediment samples were below the detection limit of 0.1 microgram kg-1 dry wt., while the overall geometric means in Arctic char muscle were, in microgram kg-1 wet wt., for PCBs 11 (range 1-140), for DDTs 4.0 (1-35), for HCHs 0.4 (0.06-1.5), for dieldrin 0.7 (< 0.1-4.2), for HCB 0.7 (0.09-3.8), for chlordanes 4.8 (1-57) and for total toxaphene 13 (1-180). The sums of PCBs, DDTs, chlordanes and total toxaphene disclosed higher concentrations in muscle of char from the east coast compared to char from the west coast. Dieldrin and HCB showed the same tendency, but less pronounced, while the sum of HCHs were found in highest concentrations at the west coast. PCB, DDT, chlordane and toxaphene concentrations showed a decreasing trend following the East Greenland Current. Principal component analysis on PCB congeners showed that the proportion of higher chlorinated PCBs (Cl > 5) were higher in Qaqortoq in south Greenland compared to the three other sampling areas in Greenland. However, no correlation was seen either between degree of chlorination and latitude or between degree of chlorination and PCB concentrations.

Animals↗
PubMed2000

Organochlorine exposure and breast cancer survival.

Recent research suggests that exposure to organochlorines, such as dieldrin that possess estrogenic properties, may increase the risk of breast cancer by promoting growth of malignant cells. Whether this potential also affects malignant cells not eradicated by treatment, and thereby survival, is unknown. To evaluate this blood samples from female participants in the Copenhagen City Heart Study, Denmark, were analyzed for organochlorines. A total of 195 breast cancer cases, who each provided two blood samples that were taken in 1976-78 and 1981-83, respectively, were included in the survival analysis. Dieldrin had a significant adverse effect on overall survival and breast cancer specific survival (RR, 2.78, 95% CI, 1. 38-5.59, P trend < 0.01; RR, 2.61, 95% CI, 0.97-7.01, P trend < 0. 01). This association was strengthened when exposure was assessed as the average serum concentration of the two measurements. These findings suggest that past exposure to estrogenic organochlorines such as dieldrin may not only affect the risk of developing breast cancer but also the survival.

Adult↗
PubMed2001

Organochlorine pesticide residues in archived UK soil.

Archived background soils ("Broadbalk', 1944-1986) and sludge-amended soils ("Luddington", 1968-1990), collected from long-term agricultural experiments in the UK, were analyzed for a range of organochlorine (OC) pesticides to establish trends over time. Concentrations typically ranged from 0.1 to 10 ng/g of soil (dry weight), with gamma-hexachlorocyclohexane (gamma-HCH), dieldrin, and p,p'-DDE consistently having the highest concentrations. The trends in the Broadbalk background soils are largely consistent with usage patterns, with peak concentrations occurring in the 1960s for DDTs and between the 1960s and the 1980s for the other OCs. In the Luddington control and sludge-amended soils, several of the OCs show a significant decline in concentrations from the late 1960s to 1990, with half-lives ranging from approximately 7 years (alpha-HCH) to approximately 25 years (dieldrin). The sludge-amended plot received 125 tonnes of sludge per ha in 1968, which was mixed in to a depth of 15 cm. It appears that the sludge treatment had little effect on concentrations in the soil, with no significant difference between control soil and sludge-amended soil for most compounds, except for HCB, p,p'-DDE, and dieldrin. Enantiomeric fractions (EFs) of some chiral pesticides (alpha-HCH, cis- and trans-chlordane, and o,p'-DDT) were determined in the Luddington soils. Results reveal that enantioselective degradation of OC pesticides is occurring in these soils for trans-chlordane (TC) and cis-chlordane (CC). However, the depletion over time is not statistically significant, and there is no statistically significant difference between EFs in the control soil and sludge-amended soil. This indicates that enantioselective microbial degradation was not consistent over time and that the addition of sludge to soil did not significantly alter the enantiomeric preference of the microbial community.

Agriculture↗
PubMed1979

Organochlorine compounds in adipose tissue of Greenlanders and southern Danes.

Abdominal fat tissue samples from the general population of Greenland and from southern Denmark were analyzed for o,p'-DDE and p,p'-DDE [1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene], p,p,-DDT [1,1,1-trichloro-2,2-bis(p-chlorophenyl)-ethane], o,p'-DDT and p,p'-DDD [1,1-dichloro-2,2-bis(p-chlorophenyl)ethane], lindane (1,2,3,4,5,6-hexachlorocyclohexane), aldrin (1,2,3,4,10,10-hexachloro-1,4,4a,5,8,8a-hexahydro-endo-exo-1,4:5,8-dimethanonaphthalene), dieldrin (1,2,3,4,10,10-hexachloro-6,7-epoxy-1,4,4a,5,6,7,8,8a-octahydro-endo-exo-1,4:5,8-dimethanonaphthalene), heptachlor (1,4,5,6,7,8,8-heptachloro-3a,4,7,7a-tetrahydro-4,7-methanoindene), heptachlor epoxide, and polychlorinated biphenyls (PCBs). Fat tissue from Greenlanders contained significantly higher amounts of p,p'-DDE (p less than or equal to 0.05), p,p'-DDT (p less than or equal to 0.01), and total DDT (SIGMA DDT, the sum of DDT and its metabolites) (p less than or equal to 0.01) than southern Danes. Lindane, aldrin-like residue, dieldrin heptachlor-like residue, heptachlor epoxide, and PCBs were present in adipose tissue of both groups and there were no significant differences between the groups. The p,p'-DDE level in Greenland was lower than that in the United States, eastern Europe, and India. Among Greenlanders of different ages the highest sigma DDT was found in the age group of 22-45 yr; the content of PCBs increased with age. Among southern Danes the highest sigma DDT was found in a higher age group than in Greenlanders. Among Greenlanders the content of aldrin-like residue decreased with age and that of dieldrin increased with age. A significant correlation was found (on the basis of wet weight) between p,p'-DDE and PCB content in southern Danes (p less than or equal to 0.02). The correlation between sigma DDT and PCB content was also significant in this population (p less than or equal to 0.01). These two relationships were not significantly correlated for the Greenlanders. The DDE/PCB and sigma DDT/PCB ratios were higher in Greenlanders than in southern Danes. These ratios are age-dependent and are highest in the age group 22-45 yr among the Greenlanders. A low DDE/PCB ratio and a low sigma DDT/PCB ratio have been proposed as markers for industrialization. In Greenlanders p,p'-DDE represented about 70% of sigma DDT. For southern Danes this level was about 90%. The data obtained are presented and discussed on the basis of both lipid and wet weight levels.

Adipose Tissue↗
PubMed2001

Dopamine transporter binding in the rat striatum is increased by gestational, perinatal, and adolescent exposure to heptachlor.

Heptachlor is a persistent cyclodiene pesticide that affects GABAergic function. Recent reports indicate that heptachlor exposure also alters dopamine transporter (DAT) expression and function in adult mice. The aim of this study was to determine whether gestational, perinatal, and/or adolescent heptachlor exposure in rats altered dopamine-receptor and DAT binding. Adolescent exposure to dieldrin was included to evaluate the generality of the findings. Sprague-Dawley rats received doses (po) ranging from 0 to 8.4 mg/kg/day of heptachlor, or dieldrin, 3 mg/kg/day, during different developmental periods. There were dose-related decreases in maternal weight gain and pup survival, as well as delayed righting reflex, at heptachlor doses > or =3 mg/kg/day. There were no changes in striatal dopamine receptor-D1 ([(3)H]SCH-23390) and -D2 ([(3)H]spiperone) binding in preweanling pups exposed perinatally to heptachlor, and no differences in the response of adult rats to the motor activity-increasing effects of d-amphetamine. However, there were significant (27-64%) increases in striatal DAT binding of [(3)H]mazindol in preweanling rats exposed only gestationally. In rats exposed perinatally and/or during adolescence, there were also increases (34-65%) in striatal DAT binding at postnatal days (PND) 22, 43, and 128. Adolescent exposure to dieldrin also increased DAT binding. In other rats exposed perinatally and throughout adolescence, even the lowest dose of heptachlor 0.3 mg/kg/d increased DAT binding on PND 130. The DAT affinity for mazindol was unchanged in heptachlor-exposed striata. In vitro binding studies indicated that heptachlor (> or =10 microM) displaced mazindol binding. Thus, gestational, perinatal, and/or adolescent exposure to heptachlor produced an increase in DAT binding as early as PND 10, and this change persisted into adulthood.

Animals↗
PubMed1984

Carcinogen induced unscheduled DNA synthesis in mouse hepatocytes.

Mouse primary liver cell cultures were examined for evidence of unscheduled DNA synthesis (UDS) following treatment with the carcinogens; dimethylnitrosamine (DMNA), diethylnitrosamine (DENA), 2-acetylaminofluorene (2-AAF), N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), benzo(a)pyrene (BP), dimethylbenzanthracene (DMBA), 1,1,-bis(p-chlorophenyl)-2,2,2-trichloroethane (DDT), safrole, diethylstilbestrol (DES), aflatoxin B1 (AFB1), and dieldrin and the noncarcinogens; dimethylformamide (DMF), fluorene, and pyrene. Mouse hepatocyte cultures were simultaneously treated with three concentrations of each compound and 3H-thymidine. After 24 hrs, cells were fixed and processed for autoradiography. 3H-thymidine incorporation in both experimental and control cell nuclei, as evidenced by autoradiographic grains, was quantitated microscopically. DMNA, DENA, 2-AAF, MNNG, BP, AFB1 and DMBA significantly increased UDS over untreated cells at all concentrations studied. DDT, DMF, fluorene, pyrene, safrole, DES, and dieldrin were negative for UDS in all concentrations examined. DMNA, 2-AAF and MNNG were also studied for UDS induction in 2 hr old, 1 day old and 4 day old cultures. A progressive decrease in UDS with increased time after plating was found in DMNA and 2-AAF treated cultures. After 4 days DMNA and 2-AAF induced UDS only at the highest concentrations examined (10(-3) M and 10(-4) M respectively). MNNG induced UDS at all time periods and concentrations sampled. An attempt to enhance the sensitivity of the UDS assay by inducing the mixed function oxidative enzyme activity in the hepatocytes with phenobarbital administered in vivo resulted in no statistically significant increase in UDS with DMNA, 2-AAF, MNNG, DDT, and dieldrin when compared with cells from non-induced animals.

Animals↗
PubMed1994

Studies on photochemical reactions of air pollutants. XII. Photochemical epoxidation of aldrin with suspended particulates in air.

Suspended particulates collected in Yokohama, Japan over various 24-h periods were found to cause the photochemical epoxidation of aldrin to dieldrin in good yield. trans-Stilbene did not undergo the epoxidation. Upon irradiation of aldrin together with the suspended particulates in quasi-air consisting of 18O2. 100% incorporation of 18O into dieldrin was obtained. Thus, the oxygen atom in dieldrin originated not from the particulates, but from oxygen in air.

Air Pollutants↗
PubMed1998

[The effects of improved diets on the daily intake of environmental contaminants as calculated from personal food consumption data, by Monte Carlo simulation].

In a previous paper, we discussed the Estimated Ecological Daily Intake (EEDI), which is a new method for the estimating daily intake of environmental contaminants based on individual food consumption data. This method makes it possible to identify high-risk cases, using a Monte Carlo simulation for varying contamination levels in each food item and permits epidemiological assessment of the individual, rather than the population, intake of environmental contaminants. We attempted to identify those contaminants whose maximum dietary levels were most commonly exceeded. The results obtained were as follows: 1) After a 1,000-fold extrapolation, performed for each person and contaminant, some cases exceeded allowable maximums in dieldrin, lead, cadmium, and total mercury. In dieldrin and lead intake, few cases exceeded dieldrin and lead maximums by a factor of 2 or 3, but in the cases of cadmium and total mercury, individual maximum intake was significantly exceeded. 2) After estimating a high-risk individual's times of exceeding the allowance in cadmium intake with dietary improvement, we found a 10.5% excess intake after 40% improvement. Clearly, the issue of environmental contaminants exposure due to dietary intake is a significant one.

Diet↗
PubMed2001

Soil-air exchange model of persistent pesticides in the United States cotton belt.

Measurements of organochlorine pesticides (lindane, cis-chlordane [CC], trans-chlordane [TC], trans-nonachlor [TN]), dieldrin, p,p'-dichlorodiphenyldichloroethylene [DDE], and toxaphene) in Alabama, USA, air and soil were used to assess the soil-air equilibrium status and to identify compounds with significant contributions to observed air burdens. Of the compounds tested, p,p'-DDE and toxaphene showed a significant potential for outgasing, followed by dieldrin and trans-nonachlor, which showed moderate outgasing potentials. Lindane, cis-chlordane, and trans-chlordane were near soil-air equilibrium. A fugacity-based, multilayered soil-air exchange model was used to predict temporal trends of chemical in air and soil resulting from reemission of soil residues to a presumed clean atmosphere (maximum emission scenario). Results showed that p,p'-DDE and toxaphene accounted for up to 50% of the observed air burden and that approximately 200 to 600 kg of p,p'-DDE and 3,000 to 11,000 kg to toxaphene are released to the atmosphere each year by soils in Alabama (area = 1.23 x 10(11) m2). High annual net fluxes were also predicted for dieldrin and trans-nonachlor (300-1,100 kg and 150-500 kg, respectively), but these only account for up to approximately 20% of their observed air burdens.

Agriculture↗
PubMed1991

Actions of insecticides on the insect GABA receptor complex.

The actions of insecticides on the insect gamma-aminobutyric acid (GABA) receptor were investigated using [35S]t-butylbicyclophosphorothionate [( 35S]TBPS) binding and voltage-clamp techniques. Specific binding of [35S]TBPS to a membrane homogenate derived from the brain of Locusta migratoria locusts is characterised by a Kd value of 79.3 +/- 2.9 nM and a Bmax value of 1770 +/- 40 fmol/mg protein. [35S]TBPS binding is inhibited by mM concentrations of barbiturates and benzodiazepines. In contrast dieldrin, ivermectin, lindane, picrotoxin and TBPS are inhibitors of [35S]TBPS binding at the nanomolar range. Bicuculline, baclofen and pyrethroid insecticides have no effect on [35S]TBPS binding. These results are similar to those obtained in electrophysiological studies of the current elicited by GABA in both Locusta and Periplaneta americana central neurones. Noise analysis of the effects of lindane, TBPS, dieldrin and picrotoxin on the cockroach GABA responses reveals that these compounds decrease the variance of the GABA-induced current but have no effect on its mean open time. All these compounds, with the exception of dieldrin, significantly decrease the conductance of GABA-evoked single current.

Animals↗
PubMed1967

Insecticide susceptibility tests on adults of Anopheles sinensis in Korea.

The authors carried out two series of field test to determine the basic lines of DDT and Dieldrin susceptibility of Anopheles sinensis at Andong(1961) and Yoju(1962), where malaria endemicity is relatively high in Korea. Tests were performed in accordance with the standard method established by the World Health Oraganization(1960). The results were summarized as follows: 1. The LC-50 of DDT for A. sinensis caught at Andong as 1.5 %, while for the same species in Yoju was 1.3 %. 2. The LC-50 of Dieldrin for A. sinensis caught at Andong was 0.075 %, while the LC-50 for the same species at Yoju was 0.07 %. These results therefore indicate Anopheles sinensis, as the malaria vector species in Korea, is susceptible to DDT and Dieldrin.

Journal Article↗
PubMed1999

A new marker, black, a useful recombination suppressor, In(2)2, and a balanced lethal for chromosome 2 of the mosquito Anopheles gambiae.

A new marker for the second chromosome of Anopheles gambiae, black, was isolated from progeny of 60Co-irradiated mosquitoes. The black mutation increases melanization of larval setae and portions of the cuticle that are heavily sclerotized such as the saddle and head capsule. Adults have a sooty color that almost completely eliminates white banding on wings, tarsi, and palps. Fertility and general vigor of black individuals is reduced relative to wild-type; however, this does not prevent routine use for genetic crossing. The black marker was mapped to an interval on chromosome 2 between collarless and Dieldrin resistance 22 centiMorgans (cM) from collarless and 39 cM from Dieldrin resistance. We also isolated from 60Co-irradiated mosquitoes a pericentric inversion, In(2)2, that was marked with dominant alleles of the independently assorting genes collarless and Dieldrin resistance. This inversion is in coupling with the pericentric inversion 2Rd and covers approximately two-thirds of chromosome 2 from divisions 9 to 22. While inbreeding In(2)2 heterozygotes, we isolated a stock in which the inversion was in repulsion to a chromosome marked with c b DlS and an unidentified recessive lethal. This arrangement produced a useful and stable chromosome 2 balancer system that has remained intact for 26 generations without selection. These genetic tools will reduce the effort requires to isolate, among other things, the genetic factors affecting malaria parasite interactions with the mosquito host.

Animals↗
PubMed1976

Organochlorine insectide residues in vegetables of the Kitakyushu District, Japan--1971-74.

The residue levels of organochlorine insecticides BHC, DDT, endrin, and dieldrin in the Kitakyushu District, Japan, were monitored from 1971 to 1974. Agricultural uses of these insecticides were banned in 1970. BHC isomers, alpha, beta, gamma, and delta-BHC were detected in all vegetable samples taken; beta-BHC residue appeared in the highest levels. The proportions of each BHC isomer in total BHC residues were much different from those in the technical product. Average residue levels of alpha, beta, gamma, and delta-BHC, dieldrin, endrin, and DDTR (p,p'-DDE+p,p'-TDE+o,p'-DDT) in 1971 were 0.007, 0.042, 0.010, 0.008, 0.021, 0.010, and 0.041 ppm in radishes, and 0.004, 0.007, 0.009, 0.003, 0.087, 0.031, and 0.009 ppm in cucumbers. Levels found in 1974 were 0.002, 0.003, less than 0.001, less than 0.001, 0.005, 0.006, and less than 0.001 ppm in radishes, and less than 0.001, 0.001, 0.001, less than 0.001, 0.008, 0.009, and undetectable in cucumbers. These residues were translocated form the insecticide-contaminated field soils to the vegetables through therir roots. Residue levels of dieldrin and endrin frequently exceeded the pesticide tolerance limits of Japan, but DDTR residues were only slightly above the specified levels.

Chromatography, Gas↗
PubMed1998

Significance of the quality of Florisil in organochlorine pesticide analysis.

During the analysis of chlorinated pesticides in animal fat tissue applying the matrix solid-phase dispersion method, and notwithstanding the use of a gas chromatograph with a highly selective capillary column, two peaks occur: one with a retention time very similar to that of lindane, and the other almost identical to that of dieldrin. Repeated analyses of the same sample with a GC/MS system revealed that neither lindane nor dieldrin were present. It was proven that those peaks resulted from florisil of local origin used for analysis, but not from the original Florisil. The removal of the first peak ("lindane") was possible through heating of florisil of local origin at 680 degrees C for 4 hours, whereas some other method would be required for the removal of the other peak ("dieldrin"). The incident proved that, in such demanding analyses, it is extremely important to use original, high quality substances to avoid possible interference and misinterpretation of results.

Adipose Tissue↗
PubMed1975

Blood organochlorine pesticide levels in Virginia residents.

This study attempts to establish 1972 baseline levels for 31 organochlorine pesticides and industrial chemicals in postmortem human whole blood in Virginia. These pesticides and industrial chemicals have been detected previously in other parts of the food chain and environment. In the present study DDT and its metabolites, DDE and TDE, were detected most frequently and at highest levels. DDT and DDE tended to appear more frequently as people grew older although TDE levels remained constant. Dieldrin and lindane showed peak levels in the middle age group. Analyzing distribution of pesticides in blood by sex showed that females had higher levels of lindane and dieldrin and males had higher levels of DDT, DDE, and TDE. Analyzing racial distribution showed blacks with higher levels of DDT, TDE, and DDE and indicated little difference from whites for lindane and dieldrin. Higher levels were found in Richmond and Norfolk than in the Fairfax and Roanoke regions.

Adolescent↗
PubMed1976

Nationwide residues of organochlorines in wings of adult mallards and black ducks, 1972-73.

Organochlorine residues in wings of adult mallards and black ducks were monitored during the 1972-73 hunting season. DDE, DDT, DDD, dieldrin, and polychlorinated biphenyls (PCB's) were present in all samples. Mallard wings from Alabama contained the highest mean levels of DDE, DDT, DDD, dieldrin, and PCB's. Mallards and black ducks from the Atlantic Flyway and mallards from the Pacific Flyway contained significantly lower DDE residues than in 1969-70. Black ducks from the Atlantic Flyway contained significantly less dieldrin than in 1969-70, and mallards in the Central and Pacific Flyways contained significantly lower levels of PCB's. As in 1969-70, DDE residues were lowest in the Central Flyway and highest in the Atlantic Flyway. The average PCB level remained unchanged in the Atlantic Flyway but was higher in the Mississippi Flyway than in 1969-70, probably because of the unusually high levels in Alabama samples. All organochlorine residues in black ducks from the Atlantic Flyway significantly correlated. DDE concentrations in mallards from the Atlantic Flyway significantly correlated with those of DDT, DDD, and PCB's.

Animals↗
PubMed1961

Resistance of Aedes aegypti to certain chlorinated hydrocarbon and organophosphorus insecticides in Puerto Rico.

Failure to control Aëdes aegypti in Puerto Rico has suggested resistance to the insecticides, particularly DDT. A laboratory colony (named Isla Verde strain) was established from material obtained near the International Airport. This strain proved highly resistant to DDT and dieldrin as well as various other insecticides. The scientific and practical significance of this is far-reaching. Heretofore, it was thought that populations of Aëdes aegypti could be resistant to the DDT group of insecticides or to the dieldrin group but not to both, and that one type of resistance involved biochemical, toxicological and genetic characteristics different from the other. This theory must now be modified or even abandoned. From the practical point of view, it is clear that the continued use of DDT or dieldrin for Aëdes aegypti control in Puerto Rico is questionable, for it is not wise to attempt to overcome high resistance by increasing the concentration or rate of application. Further, the situation demonstrated for Puerto Rico may also obtain in other islands of the Caribbean where Aëdes aegypti is known to be DDT-resistant.

Aedes↗