DDE In Adipose Tissue Research Articles

Concentrations of organochlorine pesticides and polychlorinated biphenyls in human serum and adipose tissue from Bolivia

Organochlorine pesticides and polychlorinated biphenyls (PCBs) are synthetic chemicals that are highly resistant to biodegradation and have proven adverse health effects. The objectives of this study were to determine concentrations of three selected organochlorine pesticides (p,p′-DDT, p,p′-DDE, HCB) and three specific PCB congeners (PCB 138, 153, 180) in adipose tissue and serum samples from an urban adult population (n=112) in the city of Santa Cruz de la Sierra, Bolivia, and to investigate their relationships within and between the two matrices and with selected socio-demographic characteristics. The percentages of samples positive for these compounds ranged from 40% for PCB 180 to 100% for p,p′-DDE in adipose tissue, and from 21% for HCB to 93% for p,p′-DDE in serum. Median number of residues per sample was five for adipose tissue and three for serum. Geometric mean concentrations indicate a considerable historical and recent exposure to organochlorine pesticides and PCBs in this population. Adipose tissue:serum ratios ranged from 149.3 to 590.3 (wet basis) and from 0.9 to 3.5 (lipid basis). We found positive and statistically significant correlations between adipose tissue and serum concentrations only in p,p′-DDE and HCB. This novel study in Bolivia underlines the need for human biomonitoring to assess exposure to environmental pollutants in South America.

Declining levels of PCB, HCB and p, p′-DDE in adipose tissue from food producing bovines and swine in Sweden 1991–2004

The official control programme for organochlorine (OC) contaminants in food producing animals in Sweden was used to study temporal and spatial trends of the polychlorinated biphenyl CB 153, hexachlorobenzene (HCB) and p, p′-DDE in adipose tissue from bovines and swine 1991–2004. Our results show that efforts to decrease OC contamination of animal feed and the environment have had a positive impact on the contamination of the animal production. OC concentrations declined significantly in almost all studied regions of Sweden. OC temporal trends were slower in bovines (6–8% per year) than in swine (10–12%). Power analyses showed that data from more than 10 years of sampling were needed for a detection of an annual OC level change of 5% in both species in the control programme, due to large within- and between-year variation in OC levels. CB 153 and p, p′-DDE levels were higher in southern than in northern Sweden. Levels decreased with age in milk cows, but not in young nulliparous cows (heifers) and bulls. Moreover, milk cows and bulls had significantly lower OC levels than heifers. Levels were not age-dependent among swine, but castrated male swine (barrows) had significantly lower OC levels than young female swine (gilts). Levels of the studied OCs are now in many cases below the LOQ of the analytical method used. Future time trend studies of these OCs thus depend on lowered LOQs in the control programme.

The link between the insecticide heptachlor epoxide, estradiol, and breast cancer

Given the suspected effects of estrogens on breast cancer, xenoestrogenic insecticides may be a risk factor. Studies of the weak xenoestrogen, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE), have failed to demonstrate a causal relationship, though another estrogenic organochlorine insecticide, dieldrin, belonging to the cyclodiene family, has recently been linked to breast cancer. Other cyclodienes such as heptachlor epoxide (HE) and oxychlordane (OC) present in breast tissue have not been evaluated as rigorously, presumably due to their lower concentration and lower recovery using solvent extraction procedures. We used sparging extraction coupled with gas chromatography to determine the levels of HE, OC, and DDE in adipose tissue within breast biopsies in a series of 34 women evaluated for breast abnormality. Of the three insecticides tested, only HE (p=0.007) was positively associated with prevalence of breast cancer in the biopsies. In rapid, non-genomic studies using isolated human leukocytes, flow cytometric methods were used to measure HE-induced oxidants and DNA damage. These studies indicated that HE, at concentrations similar to those in breast biopsies, induced an inverted-U increase in intracellular oxidants and DNA strand breaks [both blocked by specific nitric oxide- (NO-) synthesis blockade withL: -NMMA] in human polymorphonuclear leukocytes (PMNs). HE-treated PMNs also induced damage to surrounding lymphocytes in mixed-leukocyte incubations (also inhibited by NO blockade). The HE-induced changes in NO were inhibited by 17beta-estradiol-(17beta-E2) receptor antagonists and were mimicked by similar concentrations of 17beta-E2. The addition of tumor necrosis factor-alpha (TNF-alpha) increased intracellular oxidants and DNA damage and shifted the responses to lower HE concentrations. This study, along with others, suggests that HE-induced NO production may contribute to initiation, promotion, and progression of cancer.

Mechanisms of Movement of Organochlorine Pesticides from Soils to Cows via Forages

When cattle were allowed to graze land previously used as orchards, residues of DDE [1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene] were detectable in milk fat and adipose tissues. Concentrations of DDE exceeded .3μg/g at times. Concentrations of DDE in adipose tissue were similar to those in milk fat at the beginning of lactation; residues in first lactation cows were approximately three times higher than in multiparous cows that were grazing similarly. Based on the equation [DDE, μg/g]milk fat = .28 (daily dose, mg).82, consumption of soil was likely not the sole source of residue when soil concentrations of DDT [1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane], DDE, and DDD [1,1-dichloro-2,2-bis(p-chlorophenyl)ethane] ranged from non-detected to 3.6, 2.1, and .655μg/g, respectively. Grass appeared to be the likely source. Four plots were located on three orchard locations and one control location. Grasses in subplots were harvested at 2-, 4-, or 6-wk intervals during the 18-wk study. Grasses were extracted differentially to determine DDT and DDE residues adhering to the plant surface and those associated with plant tissue. Surface residue was not significant. The DDE averaged between .01 and .11μg/g in dry grass tissues. Differences between residues in grasses among plots were associated with soil residue concentrations. Concentrations of DDE were not associated with air or soil temperature, relative humidity, solar radiation, or dry biomass harvested. Precipitation increased the volatilization of residues from soil and deposition in 2- and 4-wk grass samples. Volatilization was confirmed by filter paper traps impregnated with ethylene glycol and suspended 15cm above the soil surface of pasture plots and in the laboratory model studies.

Organochlorine compounds in the adipose tissue of deceased persons with and without cancer: A statistical survey of some potential confounders

A case-control study on the correlation between levels of polychlorinated biphenyls (PCB) and p,p′ -DDE in adipose tissue of deceased cancer and noncancer patients is reported and related to potential confounders such as weight, height, occupation, and residence of deceased individuals, etc. Although taking into account the above-mentioned confounders, a significant association remained between the concentrations of PCB and DDE in the subcutaneous adipose fat and cancer.

Withdrawal Rates of DDT from Chickens Treated with Diphenylhydantoin

Male and female chickens of a broiler-type strain were fed, from 1 day old to 5 weeks of age, diets containing 0, 2.5, or 15.0 p.p.m. (mg/kg) 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (p,p'-DDT). Then the diets with pesticide were withdrawn and the chickens were fed dietary levels of diphenylhydantoin (DPH) at 0, 100, or 250 p.p.m. Adipose-tissue and liver samples were obtained on days 0, 10, 20, and 30 following withdrawal of diets with pesticides to determine DPH effect on DDT, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE), and 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (DDD) levels. DPH had no effect on the concentration of DDT and DDE in adipose tissue; their levels declined at a rate having a half-life value of 16 days. DDD was not detected in adipose tissue. DDT accounted for 87% of the adipose residues on day 0, but 66% of the residues at day 30. DPH had no effect on the concentrations of DDT and DDE in livers of chickens fed 15.0 p.p.m. DDT, but did significantly reduce the levels of DDD by 28 and 54% for levels of 100 and 250 p.p.m. DPH, respectively. The similarity of these data to studies on dairy cows and humans, and the dissimilarity to data from rat studies were discussed.