DDD Isomers Research Articles

The Migration of Organic Chlorine Pesticide Residues in the Composition of the Soil Samples from Mirzaabad, Gulistan and Boyovut Districts of Syrdarya Region

The thin layer chromatography gas chromatography ECD detector was employed to evaluate soil samples and wheat stalks collected during the spring season for the presence of chlorine organic pesticides, namely DDT, DDE, DDD, HCH alpha, and gamma isomers. The study revealed that the uppermost concentration of pesticides is constrained within the depth interval of 0–10(20) cm, with their infiltration extending to a depth of 2.0–2.5 m. The initial investigation focused on examining the dynamics and movement of OCP, including substances such as DDT, DDD, DDE, alpha HCH, and gamma HCH, throughout the Syrdarya region. This page provides an overview of organochlorine pesticides, their residual presence, their application in agricultural regions, and the constituent makeup of wheat stalks. In April 2023, a collection of samples was obtained from several districts within the Syrdarya region. Subsequently, a comprehensive analysis was conducted on a total of 15 samples. The gas chromatography technique with an electron capture detector (GC/ECD) was employed for the investigation of organic chlorine insecticides. The isolation and quantification of organic chlorine insecticides with low to medium polarity were achieved using a capillary column.

First evidence of legacy chlorinated POPs bioaccumulation in Antarctic sponges from the Ross sea and the South Shetland Islands

Antarctica is no longer pristine due to the confirmed presence of anthropogenic contaminants like Persistent Organic Pollutants (POPs). Benthic organisms are poorly represented in contamination studies in Antarctica although they are known to bioaccumulate contaminants. Sponges (Phylum Porifera) are dominant members in Antarctic benthos, both in terms of abundance and biomass, and are an important feeding source for other organisms, playing key functional roles in benthic communities. To the best of our knowledge, legacy chlorinated POPs such as polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB), and dichlorodiphenyltrichloroethane (DDT) and their metabolites have never been investigated in this Phylum in Antarctica. The aim of this work was to evaluate the bioaccumulation of PCBs, HCB, o,p’- and p,p’-DDT and their DDE and DDD isomers in 35 sponge samples, belonging to 17 different species, collected along the coast of Terra Nova Bay (Adèlie Cove and Tethys Bay, Ross Sea), and at Whalers Bay (Deception Island, South Shetland Islands) in Antarctica. Lipid content showed a significant correlation with the three pollutant classes. The overall observed pattern in the three study sites was ΣPCBs>ΣDDTs>HCB and it was found in almost every species. The ΣPCBs, ΣDDTs, and HCB ranged from 54.2 to 133.7 ng/g lipid weight (lw), from 17.5 to 38.6 ng/g lw and from 4.8 to 8.5 ng/g lw, respectively. Sponges showed contamination levels comparable to other Antarctic benthic organisms from previous studies. The comparison among sponges of the same species from different sites showed diverse patterns for PCBs only in one out of four cases. The concentration of POPs did not vary significantly among the three sites. The predominance of lower chlorinated organochlorines in the samples suggested that long-range atmospheric transportation (LRAT) could be the major driver of contamination as molecules with a high long range transport potential (e.g. low chlorinated PCBs, HCB) prevails on heavier ones.

Seasonal levels of pesticide residues in the main and the Blue Nile waters in Sudan

Levels of twenty-two commonly used pesticides were monitored three times a year (autumn, winter, and summer) in 54 water samples collected from six sites representing the main and Blue Nile. These sites were selected to reflect any attributes from main drainage canals from agricultural schemes in Sudan as well as any impact from upstream sources. Collected samples were subject to gas chromatographic analysis equipped with FID/ECD, and results were expressed in ng/l water. Analysis of Blue Nile water indicated the presence of OCs in 45% of the samples, OPs in 11%, pyrethroids in 22%, and none of the tested herbicides. Heptachlor and DDTs were the most prevalent followed by the pyrethroids. Levels detected were not high. Water of the main Nile showed the presence of OCs in 22% of the samples, pyrethroids in 4%, and none of the tested OPs and herbicides. DDT is the most prevalent followed by heptachlor. Total concentration in main Nile is relatively higher than the Blue Nile. Residues of DDD, λ cyhalothrin, deltamethrin, oxyfluorfen, HCH, and endosulfan isomers were not detected in the analyzed samples. Generally levels were least in autumn, followed by summer and winter. Sources of contamination might include some drains from agricultural lands in central Sudan and/or upstream sources. Both recent and old contaminations were indicated.

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.

Oral relative bioavailability of Dichlorodiphenyltrichloroethane (DDT) in contaminated soil and its prediction using in vitro strategies for exposure refinement

In this study, the bioavailability of DDTr (sum of DDT, DDD and DDE isomers) in pesticide-contaminated soil was assessed using an in vivo mouse model. DDTr relative bioavailability (RBA) ranged from 18.7±0.9 (As35) to 60.8±7.8% (As36) indicating that a significant portion of soil-bound DDTr was not available for absorption following ingestion. When DDTr bioaccessibility was assessed using the organic Physiologically Based Extraction Test (org-PBET), the inclusion of a sorption sink (silicone cord) enhanced DDTr desorption by up to 20-fold (1.6–3.8% versus 18.9–56.3%) compared to DDTr partitioning into gastrointestinal fluid alone. Enhanced desorption occurred as a result of the silicone cord acting as a reservoir for solubilized DDTr to partition into, thereby creating a flux for further desorption until equilibrium was achieved. When the relationship between in vivo and in vitro data was assessed, a strong correlation was observed between the mouse bioassay and the org-PBET+silicone cord (slope=0.94, y-intercept=3.5, r2=0.72) suggesting that the in vitro approach may provide a robust surrogate measure for the prediction of DDTr RBA in contaminated soil.

Persistent organic pollutants in liver of Brazilian sharpnose shark (Rhizoprionodon lalandii) from southeastern coast of Brazil

In the present study, persistent organic pollutants (POPs) were determined in 14 livers from specimens of the Brazilian sharpnose shark (Rhizoprionodon lalandii), which is an important economic resource for small-scale fisheries on the southeastern coast of Brazil. The following concentrations (lipid weight) of POPs were found: ∑PCBs: 1019±267ngg−1; ∑DDTs: 111±40ngg−1 and ∑PBDEs: 10.4±4.78. PCB 153 made the greatest contribution to ∑PCB (21.4%), followed by PCB 138 (14.6%) and PCB 180 (9.94%). Among chlorinated pesticides, only the p,p′-DDE and p,p′-DDD isomers had concentrations above the detection limit. Moreover, levels above the detection limit were found only for PBDE congeners 47 and 100 (BDEs 47>99). On average, BDE 47 accounted for 88% of the total PBDE load. The feeding habits of the Brazilian sharpnose shark close to the Brazilian coastline are likely the most important difference regarding the accumulation of POPs in comparison to oceanic species that feed in deeper waters. Thus, this species may be used to evaluate the pollution of coastal areas as well as human exposure to contaminants, as the Brazilian sharpnose shark is a frequently used for human consumption. Further studies in other areas of Brazil and involving other species are needed to clarify the mechanisms and potential impact of POPs, which can affect the biology of different organisms and cause population declines.

Residue of chlorinated pesticides in fish caught in the Southern Baltic

Abstract The aim of this study was to estimate the residue of chlorinated pesticides in the edible fish caught in the Gulf of Gdańsk and in the Vistula Lagoon. The highest mean concentrations of total DDT were found in the muscles of salmon (331.45 ng g−1 lw.) and sabre carp (306.29 ng g−1 lw.) caught in the Vistula Lagoon, and in the muscles of cod (309.88 ng g−1 lw.) and herring (304.86 ng g−1 lw.) from the Gulf of Gdańsk. Moreover, it was discovered that the following were present in the muscles of fish: DDT metabolites (pp’-DDE and pp’-DDD isomers) as well as hexachlorobenzene and its metabolites and endrin, dieldrin, α-endosulfan isomers and methoxychlor. Pesticides concentrations were higher in the livers of fish than in the muscles, which proves that the removal of toxins from the fish systems dominates over their accumulation. Because no concentration limits for pesticides have been defined, consumer safety assessment of fish caught in the Southern Baltic and in the Vistula Lagoon is not possible. The authors, having observed an increase in heksachlorobenzen in fish tissues suggested the existence of contemporary sources of pesticides which introduce them into the coastal zone.

PCBs and DDTs in Surface Mangrove Sediments from the South of Iran (ID NO. 048)

Mangrove sediments were collected during wet and dry seasons from nine stations in Khamir, Laft and natural reservoir mangrove-dense areas of Hormozgan province in the south of Iran. Σ PCBs ranged from 5.33 to 15.5 ng/g dry weight and the dominant congener was no.153. Average Σ DDTs for Khamir and Laft mangroves were 16.58 ± 1.51 and 18.8 ± 9.98 ng/g dry weight. DDT was more abundant than DDE and DDD isomers, which indicated the input of DDT. The sediment quality guideline shows that the concentration of Σ PCBs were below the ER-M guideline, whereas levels of Σ DDTs were between ER-L and ER-M. The mangrove ecosystem in Hormozgan province is suffering from urban and industrial development.

Differential Effect of DDT, DDE, and DDD on COX‐2 Expression in the Human Trophoblast Derived HTR‐8/SVneo Cells

The purpose of this study was to investigate the effect of 1,1,1-trichloro-2,2-bis-(chlorophenyl)ethane (DDT), 1,1-bis-(chlorophenyl)-2,2-dichloroethene (DDE), and 1,1-dichloro-2,2-bis(chlorophenyl)ethane (DDD) isomers on COX-2 expression in a human trophoblast-derived cell line. Cultured HTR-8/SVneo trophoblast cells were exposed to DDT isomers and its metabolites for 24 h, and COX-2 mRNA and protein expression were assessed by RT-PCR, Western blotting, and ELISA. Prostaglandin E₂ production was also measured by ELISA. Both COX-2 mRNA and protein were detected under control (unexposed) conditions in the HTR-8/SVneo cell line. COX-2 protein expression and prostaglandin E₂ production but not COX-2 mRNA levels increased only after DDE and DDD isomers exposure. It is concluded that DDE and DDD exposure induce the expression of COX-2 protein, leading to increased prostaglandin E2 production. Interestingly, the regulation of COX-2 by these organochlorines pesticides appears to be at the translational level.

Chiral effects in adrenocorticolytic action of o,p′-DDD (mitotane) in human adrenal cells

Adrenocortical carcinoma (ACC) is a rare malignant disease with poor prognosis. The main pharmacological choice, o,p′-DDD (mitotane), produces severe adverse effects.Since o,p′-DDD is a chiral molecule and stereoisomers frequently possess different pharmacokinetic and/or pharmacodynamic properties, we isolated the two o,p′-DDD enantiomers, (R)-(+)-o,p′-DDD and (S)-(–)-o,p′-DDD, and determined their absolute structures.The effects of each enantiomer on cell viability and on cortisol and dehydroepiandrosterone (DHEA) secretion in the human adrenocortical cell line H295R were assessed. We also assayed the o,p′-DDD racemate and the m,p′- and p,p′-isomers.The results show small but statistically significant differences in activity of the o,p′-DDD enantiomers for all parameters tested. The three DDD isomers were equally potent in decreasing cell viability, but p,p′-DDD affected hormone secretion slightly less than the o,p′- and m,p′-isomers.The small chiral differences in direct effects on target cells alone do not warrant single enantiomer administration, but might reach importance in conjunction with possible stereochemical effects on pharmacokinetic processes in vivo.

Chemical, biological, and ecotoxicological assessment of pesticides and persistent organic pollutants in the Bahlui River, Romania

Background, aim, and scope Current knowledge on environmental impacts of industrial activities in Romania, particularly persistent organic pollutants (POPs), indicates that environmental standards of the European Union are not systematically met. In our study area, additional sources of POPs are agriculture and domestic wastes. Very scarce information is available upon environmental contaminations and effects. In the present study, we investigated the chemical pollution and their eventual impact on the ecosystem by measuring POPs and by using biological indicators of pollution.

Use of the p,p'-DDD: p,p'-DDE Concentration Ratio to Trace Contaminant Migration from a Hazardous Waste Site

For approximately 50 years, beginning in the 1920s, hazardous wastes were disposed in an 11-hectare area of the Marine Corps Base (MCB) Quantico, Virginia, USA known as the Old Landfill. Polychlorinated biphenyls (PCBs) and DDT compounds were the primary contaminants of concern. These contaminants migrated into the sediments of a 78-hectare area of the Potomac River, the Quantico Embayment. Fish tissue contamination resulted in the MCB posting signs along the embayment shoreline warning fishermen to avoid consumption. In this paper, we interpret total PCB (t-PCBs) and total DDT (t-DDT, sum of six DDT, DDD, and DDE isomers) data from monitoring studies. We use the ratio of p,p'-DDD to p,p'-DDE concentrations as a tracer to distinguish site-related from regional contamination. The median DDD/DDE ratio in Quantico Embayment sediments (3.5) was significantly higher than the median ratio (0.71) in sediments from nearby Powells Creek, used as a reference area. In general, t-PCBs and t-DDT concentrations were significantly higher in killifish (Fundulus diaphanus) and carp (Cyprinus carpio) from the Quantico Embayment compared with Powells Creek. For both species, Quantico Embayment fish had mean or median DDD/DDE ratios greater than one. Median ratios were significantly higher in Quantico Embayment (4.6) than Powells Creek (0.28) whole body carp. In contrast, t-PCBs and t-DDT in channel catfish (Ictalurus punctatus) fillets were similar in Quantico Embayment and Powells Creek collections, with median ratios of 0.34 and 0.26, respectively. Differences between species may be attributable to movement (carp and killifish being more localized) and feeding patterns (carp ingesting sediment while feeding). We recommend that environmental scientists use this ratio when investigating sites with DDT contamination.

Bovine adrenal cortex transformations of mitotane [1-(2-chlorophenyl)-1-(4-chlorophenyl)-2,2-dichloroethane; o, p′-DDD] and its p, p′- and m, p′-isomers

The adrenalytic activity of mitotane ( o, p′-DDD) has made it useful in the treatment of adrenocortical carcinoma and Cushing's syndrome. In support of a study to develop mitotane analogs as more effective therapeutic agents and as a basis for understanding the toxicity of related compounds in the adrenals, the biotransformations of o, p′-DDD in adrenocortical homogenate preparations have been studied and compared with those of its m, p′- and p, p′-isomers. Aliphatic oxidation to the corresponding acetic acid derivative, o, p′-, m, p′- or p, p′-DDA, was the major transformation for all the preparations. In the comparisons of the DDD isomers, the order of both DDA formation and apparent covalent binding was o, p′- > m, p′- > p, p′-DDD. There was also evidence for α-hydroxylation at the benzylic carbon with subsequent loss of water to form ethylene derivatives. This was a minor pathway for o, p′-DDD, but was the major pathway for the other two isomers. Thus, while the total yields of metabolites of o, p′- and m, p′-DDD were similar and at least twice that of the p, p′-isomer, their distribution of metabolites differed significantly. The effects of the three isomers on cell growth and cortisol production with the human adrenocortical carcinoma cell line, NCI H-295, followed the same order as their DDA formation and tissue binding. It is proposed that hydroxylation by the adrenal cortex at the β-carbon leads to an adrenalytic effect, whereas hydroxylation at the α-carbon would represent an alternate deactivation pathway.

Adrenocorticolytic DDT-metabolites: studies in mink, Mustela vison and otter, Lutra lutra

: The irreversible binding and toxicity of the DDT metabolites p,p'-DDD and o,p-DDD in the adrenal cortex of female mink Mustela vison were studied. Histological examination of adrenals from mink given a single i.p. injection of p,p'-DDD or o,p'-DDD (125 mg per kg body weight) showed vacuolation, necrosis and focal bleedings in the zonae fasciculata and reticularis. Autoradiograms of solvent-extracted tissue sections of minks given a single i.v. injection of p,p'-[(14)C]DDD (0.7 mg per kg body weight) revealed a high level of irreversibly bound radio-activity in the adrenal cortex. Microautoradiography showed that the irreversibly bound radio-activity was confined to the zonae fasciculata and reticularis. Incubation of p,p'-[(14)C]DDD and o,p'-[(14)C]DDD with mink or otter, Lutra lutra, adrenal homogenate (300 x g supernatant) resulted in an irreversible binding of radioactivity to protein from both species. The irreversible protein binding of the DDD isomers in mink and otter was decreased by addition of the cytochrome P450 inhibitors metyrapone and carbon monoxide, indicating a cytochrome P450 dependent metabolic activation. In contrast, 3-methylsulfonyl-[(14)C]DDE, a potent adrenocortical toxicant in mice, does not appear to be metabolized to a reactive metabolite in the adrenal cortex of mink or otter. In conclusion, both p,p'-DDD and o,p'-DDD are toxic to the mink adrenal zona fasciculata and reticularis following activation in situ to reactive, tissue-binding metabolites. The results suggest that p,p'-DDD and o,p'-DDD are adrenocortical toxicants also in otter. The involvement of environmental pollutants in the generation of the adrenocortical hyperplasia observed among Baltic seals is discussed.

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.

Human colostrum as a source of organohalogen xenobiotics for a breast-fed neonate

The concentrations of p, p′-isomers of DDT, DDE, and DDD, and alpha, beta, and gamma isomers of hexachlorohexane (HCH), hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs) were determined by means of gas-liquid chromatography in 3 4 postpartum day colostrum of 54 normal women. The milk levels of t-DDT, t-HCH, HCB, and PCBs correlated significantly with one another. The contents in milk of all the studied organohalides significantly increased with maternal age. The average daily intakes of t-DDT and PCBs were estimated for the studied neonates. Values exceeding the Acceptable Daily Intake values (ADIs) recommended by the WHO for t-DDT and PCBs were found for 70.4% and 24.1% of subjects, respectively. The present study confirms the trends in organohalogen residues of human milk observed by us in the studied region's inhabitants during the 17 years of monitoring (1970–1987), i.e., a consistent decline in t-DDT levels and an increase in PCB content in the present decade as compared to the 1970s. In conclusion, despite legal restrictions in their usage, the contamination with organohalides persist in human milk at a level that may result in neonatal alimentary exposure exceeding the recommended daily intakes.

Covalent binding of four DDD isomers in the mouse lung: lack of structure specificity.

Previous studies have shown that o,p'-DDD is activated and covalently bound in the mouse lung. In order to examine the structure dependency of the selective lung binding, the 14C-labelled DDD isomers p,p'-DDD, m,p'-DDD and o,m'-DDD were injected intravenously into female C57B1 mice and covalent binding was measured. Autoradiography of solvent-extracted tape-sections showed that all isomers were selectively and covalently bound in the lung alveolar region. As determined by exhaustive extraction of homogenized tissue, maximal binding was observed 4 hr after injection, although the lung/liver concentration ratio increased for 12 days. Covalent protein binding was also observed in vitro, implying that the activation of DDD to a reactive metabolite takes place in the target organ. Since the aryl-chlorine substitution pattern did not change the selective lung binding, bioactivation of DDD may take place at the ethane side-chain.

Synthesis of 14C‐labelled DDD isomers of high specific activity

AbstractThree major DDD isomers, o,p'‐DDD, m,p'‐DDD and p,p'‐DDD, 14C‐labelled in the para‐chlorophenyl ring, have been synthesized. The DDD products were obtained in isotopic yields ranging from 42% to 58% and were of high specific activities; 31 mCi/mmol (o,p'‐DDD; m,p'‐DDD) and 19,8 mCi/mmol (p,p'‐DDD). A minor amount of 14C‐labelled o,m'‐DDD was also isolated. 400 MHz 1H NMR data of the three major DDD isomers and o,m'‐DDD were obtained.

Pesticide residues in fish and aquatic invertebrates.

Over the past 6 years a great number of fish and aquatic invertebrates from experimental and commercial fishponds have been analyzed for the presence of organochlorine insecticides and polychlorinated biphenyls (PCBs). Invariably, all specimens contained DDE and PCBs and in many instances also DDT, DDD and BHC isomers. A study of the kinetics of the organophosphorus compound parathion in an experimental fishpond ecosystem revealed a rapid bioconcentration of the chemical in algae, zooplankton, aquatic invertebrates and fish. The time-course of parathion disappearance showed an exponential type decline of the chemical over a period of three weeks.

Effect of Flooding and Organic Matter Applications on DDT Residues in Soil

AbstractA field in Coachella Valley, California which had received repeated applications of technical DDT to sweet corn (Zea mays L.) for ear worm [Heliothis yea (Boddie)] control was flooded 48 days, with and without organic matter amendments, to determine whether DDT soil concentrations could be effectively reduced. Applications of 180 and 45 metric tons/ha of feedlot manure and 18 and 5.6 metric tons/ha of alfalfa (Medicago sativa L.) meal were disked to a depth of 15 cm. Redox potentials in all flooded plots rapidly dropped below −150 mV at both the 7.5‐ and 15‐cm soil depths. All flooded plots including control plots showed a rapid decrease in soil levels of DDT isomers accompanied by a rapid accumulation of the respective DDD isomers in the top 15 cm. Flooding had little effect on the DDE isomers. By the end of the flood period p,p′‐DDT had decreased from 8.1 µg/g to 0.5 to 1.6 µg in flooded plots receiving organic amendments while the p,p′‐DDD level increased from zero to 4.2 to 5.6 µg/g. The rates of disappearance of DDT and the formation of DDD were significantly lower in the flooded plots receiving no organic amendments. After 18 days flooding the rates of p,p′‐DDT losses and DDD gains were in the order of 180 metric tons/ha manure ≃ 18 metric tons/ha alfalfa > 5.8 metric tons/ha alfalfa ≃ 45 metric tons/ha manure > control. The transformation of DDT isomers to DDD isomers occurred to a lessor extent at 15–30, 30–45, and 45–50 cm soil depths. The data indicate that flooding organic matter‐amended soil effectively reduced DDT concentrations to very low levels. The fate of DDD in flooded soils is unknown. However, through the formation of DDD, the conversion of DDT to the potentially hazardous DDE is prevented.