DDT Levels Research Articles

Sources of polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethanes (DDTs) found in surface sediment from coastal areas of Beibu Gulf: A reflection on shipping activities and coastal industries

The presence of polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethanes (DDTs) was determined in the sediments of Beibu Gulf, a newly developing industry and port in South China, to evaluate whether the rapid development of coastal cities has accelerated the organic pollution in the region. The levels of PCBs and DDTs ranged from 1.17 to 8.00 ng g−1 and ND (not detected) to 3.82 ng g−1, respectively. The levels were higher in the east of Beibu Gulf than in the west, which influenced by the industrialisation and urbanisation in the east. Additionally, penta-PCBs were the dominant PCB congeners, which are related to shipping activities, and DDTs may have originated from the historical use of technical DDT. The levels of pp′-DDD and PCBs did not have the potential to cause ecological risks in Beibu Gulf; however, residues of DDTs were at relatively higher ecotoxicological levels, thereby having the potential to cause adverse biological effects.

Chronic Exposure to Environmental DDT/DDE in 2 Species of Small Rodents: Measures of Contaminant Load, Immune Dysfunction, and Oxidative Stress.

Persistent contaminants are ubiquitous in our water and soil, and thus chronic exposure to environmentally relevant levels of these contaminants may pose a risk to humans and wildlife. Two species of small mammals (deer mouse, Peromyscus maniculatus and cotton rat, Sigmodon hispidus) were collected from historically dichlorodiphenyltrichloroethane (DDT)-contaminated and reference areas at the Redstone Arsenal (Huntsville, AL, USA), a US Environmental Protection Agency (USEPA)-designated Superfund site. Soil samples taken concurrently with mammal collection from the DDT abatement site exhibited DDT and dichlorodiphenyldichloroethylene (DDE) levels >1 ppm (USEPA total threshold limit concentration for DDT and DDE <1 ppm), whereas soil samples from the reference area had undetectable levels. Liver samples from individuals of both species collected in the contaminated areas also had significantly elevated DDT/DDE levels, with P. maniculatus averaging an approximately 20× greater load than that documented for S. hispidus. Both rodent species collected from the contaminated site had significantly lower total leukocyte counts and total differential blood cell counts (p = 0.01 and p = 0.04, respectively) than those collected from the nearby (~7000-m) reference site. Cellular stress indices also trended higher in both species, suggesting a potential for chronic exposure to DDT to act as a mediator of oxidative damage. The present study provides support to the idea that environmental exposure to low levels of contaminants can cause physiological consequences that may influence immune responsiveness and initiate cellular stress in resident mammals. Environ Toxicol Chem 2021;40:1619-1629. © 2021 SETAC.

Multi-matrix approach reveals the distribution of pesticides in a multipurpose protected area from the Atlantic Rainforest: potential risk for aquatic biota and human health?

The Atlantic Rainforest is among the main biodiversity hotspots in the world, the Yabotí Biosphere Reserve (YBR) being one of the most important remaining areas. Agriculture practices could lead to intensive usage of pesticides resulting in a risk to the environment and human health. Water, suspended particulate matter (SPM), sediment, and fish (Andromakhe paris and Andromakhe saguazu) samples were collected from four streams with different degrees of protection of the YBR in two periods in order to assess the distribution of 18 organochlorine pesticides. Legacy and current-use pesticides were found in the different environmental matrices of the stream headwaters in non-anthropized areas within the buffer zone that drains the intangible area. A similar occurrence pattern of pesticides was found in all matrices. Levels of DDTs (<3.63 ng/L) and endosulfans (<21.8 ng/L) in surface water were above international guidelines for the protection of aquatic life in several streams for both sampling periods. HCHs, DDTs, endosulfans, and chlorpyrifos were detected in SPM and sediments from three streams, while γ-HCH (<60.3 ng/g lipid weight), chlorpyrifos (<698 ng/g lw), p,p´-DDD (<367 ng/g lw), and α-endosulfans (<209 ng/g lw) were detected in fish muscle in several streams. Chlorpyrifos and endosulfans were associated with current use, while DDx/DDT ratios suggested an old use. The concentration of pesticides found would not represent a risk to human health; however, it highlights the need to establish better regulation and action guidelines to reduce the anthropogenic effect on natural reserves.

Flounders as indicators of environmental contamination by persistent organic pollutants and health risk

The purpose of this study was to elucidate the potential of using flounders as bioindicators of accumulation and transformation of POPs and to assess the possible environmental risk to the health of the population of the Russian coastal regions. The mean levels of HCH, DDT, and PCBs in the flounders were as follows: in the eastern Sea of Okhotsk, 49 ± 51, 62 ± 89, and 106 ± 83 ng/g lipid weight; in the southern Sea of Okhotsk, 36 ± 37, 15 ± 16, and 97 ± 41 ng/g lipid wt; in the Sea of Japan/East Sea, 62 ± 36, 39 ± 28, and 1616 ± 1177 ng/g lipid wt, respectively. In the Tatar Strait, OCPs were represented mainly by β-HCH with a concentration of 221 ± 182 ng/g lipid wt; the PCB level was 455 ± 317 ng/g lipid wt. Values of ILCR = 2.1·10−5 due to the consumption of flounder from the Sea of Japan/East Sea at a rate of 29 kg/yr indicate a probability of developing cancer during a lifetime.

Impact of organochlorine pollutants on semen parameters of infertile men in Pakistan

Male infertility is a major problem with important socioeconomic consequences. It is associated with several pathological factors, including but not limited to endocrine disruption as a result of environmental pollution and the alarming decline in sperm count over the decades is indicative of involvement of many environmental and lifestyle changes around the globe. Organochlorine pollutants such as dichlorodiphenyltrichlorethanes (DDTs), polychlorinated biphenyls (PCBs) and hexachlorobenzene (HCB) disrupt male reproductive system but the exact effect of environmental exposure on semen parameters in human is still not clear. This study was designed to monitor PCBs, DDTs and HCB in hair, urine and serum samples of infertile and healthy fertile men. Solid-phase microextraction gas chromatography-mass spectrometry (SPME/GC-MS) was used to monitor analytes. All tested compounds were detected, indicating recent use/persistent accumulation. Hair samples revealed no significant association with serum/urine concentrations of the analytes, while serum/urine concentrations were significantly correlated positively. Concentrations were higher in serum compared to other samples. The levels of organochlorine pollutants were higher in infertile men compared to controls with few exceptions. Among PCBs, and DDTs, PCB-153 and pp’-DDT were detected in highest concentrations, respectively. op’-DDT and pp’-DDT levels were significantly higher in infertile men compared to controls. HCB was significantly correlated negatively with sperm motility in all samples. Serum concentrations of all compounds were higher in men with defective semen parameters compared to normospermics. Serum was the best biological sample for assessing health outcomes in relation to exposure levels.

Adipose Tissue Levels of DDT as Risk Factor for Obesity and Type 2 Diabetes Mellitus.

Background:Exposure to dichlorodiphenyltrichloroethane (DDT), a potent lipophilic organochlorine pesticide, has long been linked as a risk factor for type 2 diabetes mellitus (T2DM). However, its presence in the adipose tissues of the T2DM subjects has not been explored in the Indian population, where this long-banned pesticide is still in use. The present study was conducted to evaluate the possible association of DDT and its metabolites in obese and non-obese T2DM subjects.Methods:Subjects with normal glucose tolerance (n = 50) and T2DM (n = 50) were divided into equal numbers in obese and non-obese groups. Their plasma glucose levels, HbA1c, and lipid profile were measured. The adipose tissues were collected intraoperatively, and DDT and its metabolites were measured using a gas chromatograph equipped with an electron capture detector.Results:Obese subjects, irrespective of their glycemic status, and T2DM subjects had higher concentrations of DDT. p, p’ DDT was found to increase the odds for diabetes, and o, p’ DDT for central obesity. p, p’ DDD was also strongly correlated with central obesity, glycemic parameters, and triglycerides.Conclusion:The excess deposition of p, p’ DDD, o, p’ DDT, and p, p’ DDT in obese subjects may proceed to T2DM by disrupting triglycerides and glycemic parameters.

Effect of postprandial triglycerides on DDT/ppDDE levels in subjects with varying degree of glucose intolerance

BackgroundOrganochlorine pesticides such as DDT as well as postprandial hypertriglyceridemia have been linked with insulin resistance and diabetes mellitus. The cardiometabolic risk of PPhTg could also be due to its potential to increase the serum levels of this highly lipophilic pesticide. We studied the effect of postprandial triglyceride responses to a standard oral fat challenge on the levels of DDT and its metabolites in subjects with varying degree of glucose intolerance MethodsA standard fat challenge was performed in 60 subjects who were categorized as NGT, prediabetes, and NDDM based on an earlier OGTT. Fasting and postprandial levels of serum triglycerides, plasma DDT and its metabolites were estimated and compared in the 3 groups and their association with each other, and measures of glycemia and insulin resistance were also determined. ResultsPeak Tg and TgAUC levels were significantly higher in NDDM group as compared to NGT and PD groups. TgAUC showed positive correlation with fasting plasma glucose (r=0.33, p=0.01), postprandial plasma glucose (r=0.39, p=0.002) and HOMA IR(r=0.63, p=0.001). ppDDE levels were found to be significantly higher in NDDM subjects compared with NGT group. ppDDE-AUC was significantly higher in the NDDM group compared with the other two study groups. Mean ppDDE levels also showed strong positive correlation with peak Tg (r=0.295 p=0.022), TgAUC (r=0.303 p=0.018), iPPTgAUC(r=0.57 p≤0.001) and iPPpeakTg(r=0.51 p≤0.001) as well as with FPG (r=0.269 p=0.038) PPPG (r=0.424 p=0.001) and HbA1c (r=0.321 p=0.012). ConclusionThe findings of this study support the concept that the cardiometabolic risk associated with PPhTg may at least in part be related to the associated increase in serum levels of lipophilic OCPs like DDT.

Spatial distribution, source identification, and risk assessment of organochlorines in wild tilapia from Guangxi, South China

Seventy-five wild tilapia samples from six rivers (ten sites) in Guangxi province were collected and analyzed for 53 organochlorine compounds. DDTs, endosulfan, and PCBs were the most dominant compounds found in this study. Tiandong County (TD) and Guigang City (GG) sites were found to be heavily contaminated with high levels of endosulfan (385–925 ng/g lw) and/or DDTs (20.1–422 ng/g lw). The diagnostic ratios indicated that the residues of DDTs and endosulfan in wild tilapia are associated with historical applications as well as the recent introduction of technical DDTs and endosulfan at some sampling sites. The correlation between total length, body mass, and organochlorines (OCs) was higher than the correlation between age and lipid content. There was no significant correlation between organochlorine pesticides (OCPs) and lipid content. Therefore, for organisms, the feeding intensity (related to length and mass) of fish could better reflect degree of pollution than exposure time (age) of fish. The hazardous ratios for the 50th and 95th percentile data of OCPs and PCBs in fish were both below 1, suggesting that daily exposure to OCPs and PCBs yields a lifetime cancer risk lower than 1 in 10,000.

Occurrence and distribution of HCHs and DDTs in surface water and groundwater from the Gajulamandyam region along the Swarnamukhi river basin, Andhra Pradesh, India

ABSTRACT Organochlorine pesticides (OCPs) are growing concern and ubiquitous in the environment due to their chronic toxicity, persistence, bioaccumulation, and biomagnification properties. The concentration levels of selected organochlorine pesticides (OCPs) like HCH (hexachlorocyclohexane) isomers (α, β-, γ-, δ- HCH) and DDT (dichlorodiphenyltrichloroethane) family (p,p′ – DDT, p,p′ – DDE, p,p′ – DDD) and their distribution patterns in surface water and groundwater of the study area have been investigated. Gajulamandyam region has chosen as a study area that is lying on the banks of Swarnamukhi River basin in Andhra Pradesh, India. Water samples were extracted using the SPE procedure and determined using gas chromatography-mass spectrometer (GC-MS). Concentration profile of total HCH isomers in surface water and groundwater samples have ranged from n.d.- 2970 ng/L (mean 795 ng/L) and n.d.- 2150 ng/L (mean 649 ng/L) respectively. Similarly, the concentrations of ƩDDT in surface water in the range of n.d.- 2020 ng/L (mean 653.6 ng/L) and groundwater n.d.-1540 ng/L (mean 527.3 ng/L) had been observed. The concentration distribution of ƩHCH in surface water and groundwater varied significantly with different sampling sites that indicated their sources of contamination are diverse. The OCP residue levels, namely α – HCH/γ – HCH ratios in the water indicating that it might be from long historical to a recent mixed source of the technical grade of HCHs as well as lindane. Besides, the ratios of (DDE+DDD)/DDT metabolites reveal that the source of contamination may be due to technical DDT. The residue levels of DDTs found in this investigation signifying 63% of groundwater samples exceeded the WHO recommended drinking water limits, thereby affecting human health. The spatial distribution of OCPs demonstrated the variations in pesticide burden in water bodies. The present investigation on the occurrence of HCHs and DDTs in water has advantageous because it provides baseline data for the management of water resources.

Concentrations of organochlorine pesticides in placental tissue are not associated with risk for fetal orofacial clefts

Previous epidemiological studies have shown that prenatal exposure to organochlorine pesticides (OCPs) entails a variety of adverse impacts on fetal health, but it is not yet known whether it is associated with risk for orofacial clefts (OFCs). This study of 103 fetuses or newborns with a diagnosis of OFCs (cases) and 103 healthy newborns without malformations (controls) examined whether prenatal exposure to OCPs, as indicated by their concentrations in placental tissue, is a risk factor for OFCs. No differences were found in the median concentrations of OCPs between cases and controls, with exception of o,p’-dichlorodiphenyldichloroethylene, o,p’-dichlorodiphenyldichloroethane, and total o,p’-dichlorodiphenyltrichloroethane (DDTs), whose concentrations were higher in controls than in cases (Ps < 0.05). Although higher concentrations of placental δhexachlorocyclohexane and isodrin were found to be associated with decreased risk for OFCs in logistic regression, no association was observed in the Bayesian kernel machine regression, a novel statistical model in analyzing exposure mixtures. Women who reported periconceptional folic acid supplementation had lower placental concentrations of DDTs than women who did not. In conclusion, no association between levels of OCPs in placental tissue and risk for OFCs was observed in this population. Supplementation with folic acid may help decrease the levels of DDTs in placental tissue, but further studies are needed to confirm this unexpected finding.

Distribution and sources of DDT and its metabolites in porewater and sediment from a typical tropical bay in the South China Sea

Dichlorodiphenyltrichloroethane (DDT) is well known for its harmful effects and has been banned around the world. However, DDT is still frequently detected in natural environments, particularly in aquaculture and harbor sediments. In this study, 15 surface sediment samples were collected from a typical tropical bay (Zhanjiang Bay) in the South China Sea, and the levels of DDT and its metabolites in sediment and porewater samples were investigated. The results showed that concentrations of DDXs (i.e., DDT and its metabolites) in bulk sediments were 1.58–51.0 ng g−1 (mean, 11.5 ng g−1). DDTs (DDT and its primary metabolites, dichlorodiphenyldichloroethane (DDD) and dichlorodiphenyldichloroethylene (DDE)) were the most prominent, accounting for 73.2%–98.3% (86.1% ± 12.8%) of the DDXs. Additionally, high-order metabolites (i.e., 1-chloro-2,2-bis(4′-chlorophenyl)ethylene (p,p′-DDMU), 2,2-bis(p-chlorophenyl)ethylene (p,p′-DDNU), 2,2-bis(p-chlorophenyl)ethanol (p,p′-DDOH), 2,2-bis(p-chlorophenyl)methane (p,p′-DDM), and 4,4′-dichlorobenzophenone (p,p′-DBP)) were also detected in most of the sediment and porewater samples, with DDMU and DBP being predominant. The DDTs concentration differed among the sampling sites, with relatively high DDTs concentrations in the samples from the aquaculture zone and an area near the shipping channel and the Haibin shipyard. The DDD/DDE ratios indicated a reductive dichlorination of DDT to DDD under anaerobic conditions at most of the sampling sites of Zhanjiang Bay. The possible DDT degradation pathway in the surface sediments of Zhanjiang Bay was p,p′-DDT/p,p′-DDD(p,p′-DDE)/p,p′-DDMU/p,p′-DDNU/ … /p,p′-DBP. The DDXs in the sediments of Zhanjiang Bay were mainly introduced via mixed sources of industrial DDT and dicofol, including fresh input and historical residue. The concentrations of DDXs in porewater samples varied from 66.3 to 250 ng L−1, exhibiting a distribution similar to that in the accompanying sediments. However, the content of high-order metabolites was relatively lower in porewater than in sediment, indicating that high-order degradation mainly occurs in particles. Overall, this study helps in understanding the distribution, source, and degradation of DDT in a typical tropical bay.

Organochlorine Residues Levels in Some Selected Kolanuts (Cola nitida Schott &amp; Endl.) in Côte d’Ivoire

Aims: The aim of this study was to assess the level of organochlorine pesticide (OCPs) residues in some selected kolanuts in Côte d’Ivoire.&#x0D; Study Design: Kolanuts samples were collected from farmers, collectors and urban stores in 3 regions, in particular western, southwestern and eastern of Côte d’Ivoire.&#x0D; Place and Duration of Study: Health Department of Hydrology Health and Toxicology, Training and Research Unit of Pharmaceutical and Biological Sciences, Abidjan, Côte d’Ivoire, running 2017-2018.&#x0D; Methodology: A total of 225 samples were analyzed using a gas chromatograph equipped with an electron capture detector.&#x0D; Results: Data showed that all 17 pesticides analyzed were detected in kolanuts samples. Statistical analysis indicated no significant difference in OCPs sub-group used by farmers and traders in all producing region. The mean levels of HCHs, DDTs and cyclodienes were ranged from 0.07± 0.01– 0.91± 0.05 mg/kg, 0.15±0.01 – 0.61±0.12 mg/kg and 0.12±0.03 - 0.84±0.46 mg/kg, respectively. Otherwise, farmer’s levels of OCPs were lower than those detected in kolanuts from collectors and urban stores samples. Thus, compared to the MRL set by the World Health Organization/Food and Agricultural Organization, the farmer’s samples are lower than limits fixed, unlike the contents registered with collectors and urban stores.&#x0D; Conclusion: There is the need to keep monitoring ecotoxicological chemical substances in kolanuts produced in Côte d’Ivoire and take steps that ensure health safety of end users. Care should be taken since residues could pose chronic health risk for adults and children.

Dissipation of organochlorine insecticide residues in the environment of Taiwan, 1973-1999

Organochlorine insecticides were used in Taiwan for agricultural and public health purposes mainly from 1950 to 1974. In this study, various survey and analysis studies on soil, water, sediment and animals from 1973 to 1999 were compared, temporal trends were analyzed, and the significance was discussed. In 1973, DDT, DDE, DDD, dieldrin, lindane and aldrin were the major organochlorine insecticides found at higher levels in rice paddy soil in Taiwan. In 1981, average total DDTs concentration of surface soil decreased to one-third of the 1973 level. Subsequently in 1994, total DDTs concentration in surface soil again decreased to one-third of the 1981 level. Dieldrin, lindane and aldrin concentrations decreased even faster and were much lower compared to DDT since 1981. Organochlorine insecticide mean concentrations in river water had reached ppt levels from 1973-1976, but were rarely detected in the 1990s. River sediment concentrations showed a rapid decrease from 1973 to 1976, but although there were variations among different rivers in Taiwan, sediment concentrations of lindane, DDT, DDE and aldrin reached a few ppb and were higher in 1981 compared to 1973-1976 on average. In recent years, total organochlorine insecticide concentration decreased to the ppb level, with most individual insecticide concentrations below 1 ppb. Shellfish organochlorine pesticide concentrations were slightly higher than sediment, and shellfish DDT, DDE, aldrin, dieldrin concentrations also showed an increase from 1973 to 1983 on average. The mean concentrations of DDT and aldrin were higher than 10 ppb in shellfish in 1983 and decreased to below the ppb level in the 1990s. Fish muscle contained ppb levels of organochlorine insecticides in 1973. In recent years, most of the organochlorine insecticide concentrations in shellfish and fish were less than 1 ppb except DDE. Duck eggs and human milk had been found to contain sub ppm levels of DDT and DDE in the 1970s and 1980s, but there was few recent data available. Although organochlorine insecticide levels in the environment of Taiwan have fallen fast over the last 26 years, DDTs and other organochlorine insecticide residue levels in higher animals should be determined for their bioaccumulation potential through the food chain.

Abstract A48: Perinatal DDT exposure shortens latency of mouse mammary tumorigenesis

Abstract The contribution of exposure to the persistent, lipophilic pesticide dichlorodiphenyltrichloroethane (DDT) to breast cancer risk is controversial. A recent report by the International Agency for Research on Cancer (IARC) concluded that no consistent association exists between DDT exposure and breast cancer, yet stressed that there was a lack of existing evidence to allow for the determination of the effects of early-life exposure to DDT. It has been hypothesized that exposure to DDT during critical periods of breast development may increase breast cancer risk. We hypothesized that perinatal DDT exposure would result in shortened latency of spontaneous mammary tumorigenesis and accelerated growth of mammary tumors and increase the incidence of lung metastasis. To test the effect on mammary tumor early progression and growth as well as lung metastasis, C57BL/6J female mice, pregnant as a result of mating with B6.FVB-Tg(MMTV-PyVT)634Mul/LellJ male mice, were administered DDT from gestational day 11.5 to postnatal day 5 to produce circulating levels of DDT in dams within the prenatal range associated with breast cancer in adult daughters. This perinatal DDT exposure significantly accelerated the development of palpable mammary tumors (hazard ratio = 3.7 (95% confidence interval 2.0-6.8; p&amp;lt;0.0001). We also aimed to study possible mechanisms for DDT increasing mammary cancer risk, including alterations in puberty tempo and the presence of breast cancer risk factors associated with impaired metabolism. We found that mice exposed to DDT perinatally had increased terminal end buds in their mammary glands late in puberty (postnatal day 63, p&amp;lt;0.05). Tumor-free mice exposed to DDT perinatally also had significantly elevated circulating glucose levels (p&amp;lt;0.05). The risk of mammary cancer associated with perinatal DDT exposure observed in mice closely mirrors that observed in women previously. Our findings raise the possibility that perinatal DDT exposure may increase risk of breast cancer through its effects on pubertal mammary gland development and/or on glucose homeostasis. Future research to further evaluate whether these effects are mechanisms by which perinatal DDT exposure accelerates breast tumorigenesis is highly warranted. Citation Format: Tomoko Ishikawa, Jason Tong, Alexander Borowsky, Robert Cardiff, Michele La Merrill. Perinatal DDT exposure shortens latency of mouse mammary tumorigenesis [abstract]. In: Proceedings of the AACR Special Conference on Environmental Carcinogenesis: Potential Pathway to Cancer Prevention; 2019 Jun 22-24; Charlotte, NC. Philadelphia (PA): AACR; Can Prev Res 2020;13(7 Suppl): Abstract nr A48.

Bioaccumulation and human health risk assessment of DDT and its metabolites (DDTs) in yellowfin tuna (Thunnus albacares) and their prey from the South China Sea

DDTs were detected in yellowfin tuna (Thunnus albacares, 92.1–221.8 ng‧g−1 lipid weight) and their prey (54.9–93.5 ng‧g−1 lipid weight) from the South China Sea (SCS). DDT levels reported in this study were lower than those of the previous studies indicated the recent mitigation of DDT contamination in the SCS. Higher DDT levels were observed in fat abdominal muscle than lean dorsal muscle in adult yellowfin tuna. Meanwhile, DDT levels in adult yellowfin tuna were higher than the young ones. The composition profiles of DDT and its metabolites suggested DDTs in fish in the SCS were mainly derived from the historical use of technical DDTs. DDTs were biomagnified through food chains with the trophic magnification factor of 2.5. Risk assessment results indicated that dietary exposure to DDTs through lifetime fish consumption from the SCS would pose little cancer and noncarcinogenic risk to coastal residents.

Association between maternal exposure to the pesticide dichlorodiphenyltrichloroethane (DDT) and risk of obesity in middle age.

Background:Obesity is a malnourishment epidemic worldwide. A meta-analysis of prospective human studies across the world demonstrated a consistent positive association between maternal exposure to the pesticide dichlorodiphenyltrichloroethane (DDT) and its metabolite dichlorodiphenyldichloroethylene (DDE) and children with obesity. The present study evaluates the association of maternal exposure to DDT and DDE with the risk of obesity in daughters during their mid-life in a prospective birth cohort with up to 53 years of follow-up.Methods:Gravidas’ blood was collected during their 1959–1967 enrollment into the prospective Child Health and Development Studies birth cohort in California. Their daughters aged 44–53 years had their height, weight, and waist circumference measured during a home visit to evaluate associations of daughters’ adiposity and relative risk of overweight and obesity with their mothers’ prenatal serum levels of DDT and DDE quantified by gas chromatograph-tandem mass spectrometer (n=511).Results:Maternal o,p’-DDT was positively associated with body mass index (beta=0.59 kg/m2 per ln ng/ml (95th percentile confidence interval, 95CI: 0.17, 1.00)) and waist circumference (beta=1.19 cm per ln ng/ml (95CI: 0.26, 2.13)) in multivariable models. Maternal o,p’-DDT was positively associated with a 26% (95CI: 6–49%) to 31% (95CI: 6–62%) higher risk of overweight and the same magnitude of additional risk for obesity, based on waist circumference and BMI definitions respectively, in multivariable models.Conclusions:These data indicate maternal DDT exposure is significantly associated with increased obesity risk among middle-aged women independent of the obesity definition, confounding, and obesity risk factors. Our findings suggest that policies supporting the use of DDT for malaria vector abatement need to consider the obesity risk as a health cost when weighing the benefits of using DDT in malaria vector control.

An assessment of eggshell pigments as non-invasive biomarkers of organochlorine pollutants in gull-billed tern

Eggshell pigmentation has been assessed as an indicator of exposure to environmental pollutants in birds, but these studies have only used reflectance spectrophotometry to measure such pigmentation. The present study is the first one that measures eggshell pigments and pollutants in the same eggs to explore their use as biomarkers in birds. We have studied the concentration of organochlorine pesticides and polychlorinated biphenyls (PCBs) in the content of 97 deserted eggs of gull-billed terns (Gelochelidon nilotica) after the abandonment of the colony in Mesas de Asta (Cádiz, S Spain) in 2012. Eggshell thickness and stage of embryo development were studied together along with the concentrations of protoporphyrin IX and biliverdin in eggshells. p,p′-DDE concentrations were high when compared with other studies done with terns in the Mediterranean basin in the past. p,p′-DDE and PCB levels associated with reduced reproductive success were found in 5.1% and 2.1% of the eggs respectively. Eggshell index was largely affected by the embryo development stage, which highlights the need of knowing this information to avoid potential biases in the interpretation of results. The concentrations of protoporphyrin IX and biliverdin in the eggs of gull-billed terns were negatively associated with DDTs levels, which seems to confirm previous observations with phylogenetically related species.

Legacy persistent organic pollutants (POPs) in archive samples of wild Bluefin tuna from the Mediterranean Sea

Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were quantified in archive samples of dorsal white muscle of the wild Bluefin tuna (BFT) (n = 9) collected in the central Adriatic. PCBs were the predominant organochlorine (OC) compounds (60.8–69.4% of the total OC load) found. The contribution of HCB and ΣHCHs was significantly lower, ranging from <LOD (α- and β-HCH) to 1.5% (γ-HCH). p,p′-DDE was the predominant OCP compound (60–89% of the ΣOCPs). PCB and DDT levels were comparable to the values previously found for tuna from the Mediterranean Sea, known as one of the areas most polluted by PCBs.

Spatial distribution patterns and human exposure risks of polycyclic aromatic hydrocarbons, organochlorine pesticides and polychlorinated biphenyls in Nepal using tree bark as a passive air sampler

Nepal is abutted between the populated Indo-Gangetic Plain (IGP) and Himalayan mountains. Currently, knowledge on the country-wide distribution and cancer risks of atmospheric organic toxicants in Nepal remains limited. In this study, the concentrations, sources, and distributions of polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), and polychlorinated biphenyls (PCBs), along with their cancer risks, were investigated in Nepal by using tree bark as a passive air sampler. After transferring by a bark/air partitioning model, the averaged concentrations of ∑PAHs, ∑DDTs, ∑HCHs, HCB, ∑Endo and ∑PCBs in the atmosphere of Nepal were 3.71 × 104 pg/m3, 1.10 × 103 pg/m3, 2.92 × 102 pg/m3, 4.38 × 102 pg/m3, 4.66 pg/m3 and 65.8 pg/m3, respectively. Source diagnosis suggested that biomass burning is the major source for PAHs, while local application and long-range transport jointly contribute to the high levels of DDT and HCH in the air. The ILCR (incremental lifetime cancer risk) value was used to assess the risks of various chemicals. Adults have a higher risk than other age groups; the major exposure pathway for risk is by inhalation; and PAHs and HCHs are the dominant chemical classes that lead to risk. It was also found that, in certain hotspots in south Nepal, the carcinogenic risks caused by DDT and HCH were particularly high (>1 × 10−4). Given that illegal and disordered use of legacy POPs in south Nepal and the IGP region is common, our results highlight an urgent need for voluntary regulation of the ongoing use of pesticides.

The uptake modeling of DDT and its degradation products (o,p′-DDE and p,p′-DDE) from soil

Dichloro-diphenyl-trichloroethane (DDT) has been extensively used to control malaria during World War II as well as the other agricultural pests. DDT persists in the environment and accumulates in many living organisms. Also, the degradation products of DDT, which have also a similar chemical structure, could pose the same risk to the environment and human health. Measuring DDT and its degradation products in the environment could be challenging and costs money and time. Thus, modeling is an alternative method used by researchers to estimate the environmental relevant levels of the contaminants. The present study estimates the uptake levels of DDT and its degradation products i.e. o,p′-DDE and p,p′-DDE by crop-specific models (e.g. root, potato, leafy vegetables, cereal, fruit-tree models) in the root, potato, leaves, fruit, cereal, and water compartments by using the known environmental concentrations of DDT and its degradation products (µg kg−1) in soil sampled from Soke, Aydin. According to the crop-specific model results, predicted accumulation levels of DDT and its degradation products were found mainly in leafy vegetables, roots, cereals, and potato. The highest concentration levels were found in leafy vegetables in soil, followed by root, cereals, and potato respectively; however, leaves, fruits, and water had a low amount of accumulation of DDT and its degradation products. Further models are needed to evaluate risk assessment of the environmental compounds to human health and the environment.