Serum Organochlorine Pesticides Research Articles

Mixture analysis of serum organochlorine pesticides concentrations and diabetes mellitus in women from Northern Mexico

Mixture analysis of serum organochlorine pesticides concentrations and diabetes mellitus in women from Northern Mexico

Organochlorine pesticide residues and urinary arsenic and fluoride levels in mothers and their newborns who are residents of rural areas in Durango State, Mexico

ABSTRACT Maternal and prenatal exposure to organochlorine pesticides (OCP), arsenic (As), and fluoride (F−) is a critical public health concern. The present study assessed serum OCP residues and urinary As and F− levels in mother and newborn pairs who are residents of rural areas of Durango State, Mexico, from August 2018 to February 2019. Levels of OCP, As, and F− were measured in serum and urine samples by Gas chromatography – Tandem mass spectrometry (GC – MS/MS), Hydride generation – Atomic fluorescent spectrometry (HG-AFS, and ion-selective electron analysis (ISE), respectively, in 60 binomial mothers – newborns. Dieldrin, endrin aldehyde, and endosulfan-II were significantly higher in newborns than in mothers (p ˂0.05). Meanwhile, no significant differences were observed for As and F− concentrations between mother – newborn pairs. Differences were observed in ∑Dienes and ∑DDTs comparing newborns with normal and low birth weights and a positive relationship in ƩDienes, ƩChlordanes, and ƩDDTs between mother and newborn pairs (p ˂ 0.05). These findings highlight the importance of extensive research regarding the influence of pollution.

Breast cancer immunophenotypes and serum organochlorine pesticides in Mexican women: Mixture exposure approach

Epidemiological studies on associations between breast cancer (BC) and organochlorine pesticides (OCP) are inconclusive. The majority of studies have evaluated the effect of single compounds without considering multiple OCP exposures and immunophenotypes of BC. We aimed to evaluate the association between BC immunophenotypes and serum OCP mixtures, and identify the main contributors within mixtures. We included 767 histopathologically confirmed incident BC cases and 908 controls from a population-based case-control study conducted from 2007 to 2011 in Northern Mexico. We obtained direct information about sociodemographic, lifestyle and reproductive characteristics. We collected data from clinical records about hormonal receptors (HR) and epidermal growth factor receptor 2 (HER2) expressions. Immunophenotypes were determined as HR+/HER2−, HER2+ or HR−/HER2−. We quantified OCP and metabolites by gas chromatography using an electron capture micro detector. We used Weighted Quantile Sum regression to assess the association of BC and exposure to multiple OCP, and their contribution within the mixture. We found a positive adjusted association between BC and an OCP mixture (OR: 3.48, 95%CI: 2.58, 4.69), whose primary contribution arose from the isomers of hexachlorocyclohexane and endosulfan, as well as endosulfan sulfate. We also identified a mixture negatively associated (OR: 0.13, 95%CI: 0.08, 0.20), characterized by p,p'-DDT and chlordane metabolites. All these associations remained regardless BC immunophenotypes. This is the first epidemiological report that identified serum OCP mixtures associated with BC immunophenotypes. Due to OCP ubiquity, biomagnification, and continuous exposure, they constitute a global problem of persistent exposure that might be related to BC risk.

Diabetes mellitus and serum organochlorine pesticides mixtures in Mexican women

BackgroundVery recently, it has been reported that exposure to different mixtures of organochlorine pesticides (OCP) is associated with the development of diabetes mellitus (DM). In Mexico, DM is a public health problem that might be related to the historical intense use of OCP. We aimed to evaluate, the association between DM and serum concentrations of OCP mixtures, and identify the main contributors within them.MethodsWe conducted a secondary cross-sectional analysis on the control group from a breast cancer population-based case-control study conducted from 2007 to 2011 in Northern Mexico. We identified 214 self-reported diabetic women and 694 non-diabetics. We obtained direct information about sociodemographic, lifestyle and reproductive characteristics. We determined 24 OCP and metabolites in serum by gas chromatography using an electron capture micro detector. We used Weighted Quantile Sum regression to assess the association of DM and exposure to multiple OCP, and the contribution of each compound within the mixture.ResultsWe found a positive adjusted association between DM and an OCP mixture (OR: 2.63, 95%CI: 1.85, 3.74), whose primary contribution arose from p, p’-DDE (mean weight 23.3%), HCB (mean weight 17.3%), trans nonachlor (mean weight 15.4%), o, p’-DDE (mean weight 7.3%), heptachlor epoxide (mean weight 5.9%), oxychlordane (mean weight 4.7%), and heptachlor (mean weight 4.5%). In addition, these OCP along with p, p’-DDT and cis chlordane, were of concern and remained associated when excluding hypertensive women from the analysis (OR 2.55; 95% CI 1.56, 4.18).ConclusionsOur results indicate, for the first time in a Latin-American population, that the concomitant exposure to multiple OCP is associated with DM. Further research is needed since the composition of OCP mixtures may vary according to regional pesticides use patterns.

Association between exposure to a mixture of organochlorine pesticides and hyperuricemia in U.S. adults: A comparison of four statistical models

The association between the exposure of organochlorine pesticides (OCPs) and serum uric acid (UA) levels remained uncertain. In this study, to investigate the combined effects of OCP mixtures on hyperuricemia, we analyzed serum OCPs and UA levels in adults from the National Health and Nutrition Examination Survey (2005–2016). Four statistical models including weighted logistic regression, weighted quantile sum (WQS), quantile g-computation (QGC), and bayesian kernel machine regression (BKMR) were used to assess the relationship between mixed chemical exposures and hyperuricemia. Subgroup analyses were conducted to explore potential modifiers. Among 6,529 participants, the prevalence of hyperuricemia was 21.15%. Logistic regression revealed a significant association between both hexachlorobenzene (HCB) and trans-nonachlor and hyperuricemia in the fifth quintile (OR: 1.54, 95% CI: 1.08–2.19; OR: 1.58, 95% CI: 1.05–2.39, respectively), utilizing the first quintile as a reference. WQS and QGC analyses showed significant overall effects of OCPs on hyperuricemia, with an OR of 1.25 (95% CI: 1.09–1.44) and 1.20 (95% CI: 1.06–1.37), respectively. BKMR indicated a positive trend between mixed OCPs and hyperuricemia, with HCB having the largest weight in all three mixture analyses. Subgroup analyses revealed that females, individuals aged 50 years and above, and those with a low income were more vulnerable to mixed OCP exposure. These results highlight the urgent need to protect vulnerable populations from OCPs and to properly evaluate the health effects of multiple exposures on hyperuricemia using mutual validation approaches.

Mixture analysis of serum organochlorine pesticides concentrations and breast cancer in women from Northern Mexico

Mixture analysis of serum organochlorine pesticides concentrations and breast cancer in women from Northern Mexico

Circulating organochlorine pesticide levels, genetic predisposition and the risk of incident type 2 diabetes

Persistent organochlorine pesticide (OCP) has been associated with type 2 diabetes (T2D), and genetic polymorphism might modify such an association. However, prospective evidence remains scarce. We conducted a nested case-control study comprising 1006 incident diabetic cases and 1006 matched non-diabetic controls [sex and age (±5 years)] from 2008 to 2013 (mean follow-up period: ∼4.6 years) based on the Dongfeng-Tongji cohort in Shiyan City of China, determined baseline levels of nineteen OCPs, and examined the associations of circulating OCPs, both individually and collectively, with incident T2D risk. We also constructed overall genetic risk score (GRS) based on 161 T2D-associated variants and five pathway-specific cluster GRSs based on established variants derived from the Asian population. Compared with the first quartile of serum β-BHC levels, the multivariable-adjusted ORs (95% CIs) of incident T2D risk in the second, third, and fourth quartiles were 0.98 (0.70–1.39), 1.43 (0.99–2.07), and 1.75 (1.14–2.68), respectively (FDR-adjusted Ptrend = 0.03). A positive association was observed between serum OCP mixture and incident T2D risk and can be largely attributed to β-BHC. Furthermore, serum β-BHC and p,p’-DDE showed significant interactions with the GRS for lipodystrophy, a T2D-related pathway representing fat redistribution to viscera, on T2D risk (Pinteraction < 0.05). In conclusion, higher circulating OCP levels were independently associated with an increased risk of T2D, with β-BHC possibly being the major contributor. Genetic predisposition to T2D-related morbidity, such as visceral adiposity, should be considered when assessing the risk of T2D conferred by OCPs.

Biomonitoring of organochlorine pesticides and cancer survival: a population-based study.

Organochlorine pesticides (OCPs) are endocrine-disrupting chemicals (EDCs) that even at very low levels can cause cancer by increasing the activity of tumor cells and suppressing the immune system. There is also little information on OCPs and survival after diagnosis. The aim of this study was to monitor the concentration of OCPs in the blood serum of cancer patients and its relationship with their socio-demographic characteristics and ultimately that impact on survival time and hazard ratio (HR). This cross-sectional study included 89 diagnosed patients with cancer in Isfahan, Iran. 12 types of OCPs were measured in serum by gas chromatography (7GC) with an electron capture detector and equipped with mass spectrometer (MS). Also, participants' questionnaire was completed to collect information. T-test, ANOVA, and Chi-square tests were used to evaluate the association between serum levels of OCPs and quantitative and qualitative information of patients. Survival analysis was also examined based on Kaplan-Meier method, log-rank test, and Cox model. The mean of total OCPs in patients' serum was calculated to be 1.82 ± 1.36μg/L. Concentration of 2,4' DDE had a significant relationship with body mass index (BMI) (kg/m2) (P < 0.05). In addition, gender revealed a significant correlation in estimating survival time (P < 0.05). Non-exposure to OCPs showed a positive effect on increasing the life expectancy of patients. Lindane and endosulfan increased the risk of death by 16% and 37%, respectively, with insignificant P value (P > 0.05). The findings of the present study showed adverse effects of OCPs on patients' survival time and increased mortality of HR. Moreover, as the first research conducted in the study area, it is suggested management of environmental, individual and social factors that could be influenced the biological accumulation of OCPs in humans and cause health promotion.

Organochlorine pesticide exposures, metabolic enzyme genetic polymorphisms and semen quality parameters among men attending an infertility clinic.

The associations of organochlorine pesticides (OCPs) with semen quality from human studies are conflicting, and also it is largely unknown whether the associations are modified by genetic polymorphisms. We aimed to evaluate the associations between serum concentrations of 18 OCPs and semen quality among 387 Chinese men, and further to examine the modifying effects by genetic polymorphisms in cytochrome P450 (CYP2E1) and glutathione S-transferase (GSTT1). Multivariable linear regressions were used to evaluate the relationships between serum OCP concentrations and semen quality, and the role of CYP2E1 and GSTT1 polymorphisms in modifying the associations were assessed. Multiple testing was adjusted using the false discovery rate (FDR). We observed that men with detectable concentrations of serum ɤ-HCH had a decrease in sperm motility of 7.07% (95% CI: -10.9%, -3.24%) compared to those with undetectable concentrations (FDR-P value=0.02). Men with TT of CYP2E1 rs 915906 genotypes had higher median concentrations of serum dieldrin compared with those with CT/CC of CYP2E1 rs 915906 genotypes. There were interactions between CYP2E1 and GSTT1 polymorphisms and certain OCPs namely ɤ-HCH, δ-HCH, dieldrin, endosulfan I, and endrin aldehyde on semen quality. For example, elevated dieldrin levels in relation to decreased sperm concentration, sperm count, and sperm motility were only observed among men with CC of CYP2E1 rs2031920 genotypes (all Pinteraction < 0.05). However, these interactions were not statistically significant after the FDR adjustment. Our results suggested that CYP2E1 and GSTT1 polymorphisms may modify the effects of OCP exposures on semen quality. Due to the relatively small size samples, further investigation is warranted to confirm the findings.

Exploring the association of organochlorine pesticides exposure and hearing impairment in United States adults

Hearing loss (HL) is a highly prevalent public health concern. Organochlorine pesticides (OCPs) are widely used environmental pollutants harmful to human health. Studies investigating the effects of OCPs exposure on the auditory system in the general population are rare. To explore the association between OCPs exposure and HL in adults, 366 adults aged 20–69 years who participated in the National Health and Nutrition Examination Survey (NHANES, 2003–2004) were investigated. HL was defined as a pure-tone average (PTA) ≥ 20 dB in the better ear. Multivariate linear and logistic regression analyses were conducted to evaluate the association of four selected serum OCPs with PTAs and the risk of HL. In participants aged < 60 years, hexachlorobenzene (HCB) and dichlorodiphenyldichloroethylene (p, p'-DDE) exposure was positively associated with low- and speech-frequency PTAs, and with low-frequency HL, respectively. Risk of HL increased in the highest tertile compared with the lowest tertile of serum HCB and p, p'-DDE (odds ratio [OR]: 4.38, 95% confidence interval [CI]: 0.97–19.80; OR: 16.66, 95% CI: 2.64–105.09, respectively). In this study of US adults aged < 60 years, HCB and p, p'-DDE exposure was positively associated with HL. HCB and p, p'-DDE may be potential risk factors for HL.

Temporal Trends of Exposure to Organochlorine Pesticides in the United States: A Population Study from 2005 to 2016.

The current study aimed to investigate temporal trends of serum organochlorine pesticide (OCP) concentrations in the general United States population, approximately 30 years after the prohibition of OCP usage, by using National Health and Nutrition Examination Survey data. The least square geometric means and percent change in OCP concentrations were calculated by a survey weighted multiple linear regression model. Over 2005–2016, OCP concentrations showed significant downward temporal trends. Females had substantially higher concentrations of β-Hexachlorocyclohexane (β-HCH), p,p′-DDE and p,p′-DDT, but lower concentrations of Hexachlorobenzene (HCB) and trans-nonachlor. In addition, females had a more rapid decrease in p,p′-DDT levels over time than males. The overall OCP concentrations increased with age, and the two oldest age groups (aged 40–59 and 60+ years) had substantially lower rates of decrease than the younger age groups (aged 12–39 years). Concentrations and declines in OCPs (except for trans-nonachlor) were higher in Mexican Americans than both non-Hispanic Whites and non-Hispanic Blacks. There is a particular need for the ongoing monitoring of these banned chemicals, and measures should be taken to mitigate the exposure of vulnerable populations, including adults aged over 60, Mexican Americans, females for β-HCH, p,p′-DDE and p,p′-DDT, and males for HCB and trans-nonachlor.

Effect of Low-Dose Persistent Organic Pollutants on Mitochondrial Function: Human and in Vitro Evidence.

BackgroundChronic exposure to low-dose persistent organic pollutants (POPs) can induce mitochondrial dysfunction. This study evaluated the association between serum POP concentrations and oxygen consumption rate (OCR) as a marker of mitochondrial function in humans and in vitro cells.MethodsSerum concentrations of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were measured in 323 adults. The OCRs of platelets and peripheral blood mononuclear cells (PBMCs) were assessed in 20 mL of fresh blood using a Seahorse XF analyzer. Additionally, the in vitro effects of Arochlor-1254, β-hexachlorocyclohexane, and p,p′-dichlorodiphenyltrichloroethane at concentrations of 0.1 pM to 100 nM were evaluated in human platelets, human PBMCs, and Jurkat T-cells.ResultsThe association between serum POP concentrations and OCR differed depending on the cell type. As serum OCP concentrations increased, basal platelet OCR levels decreased significantly; according to the OCP quintiles of summary measure, they were 8.6, 9.6, 8.2, 8.0, and 7.1 pmol/min/μg (P trend=0.005). Notably, the basal PBMC OCR levels decreased remarkably as the serum PCB concentration increased. PBMC OCR levels were 46.5, 34.3, 29.1, 16.5, and 13.1 pmol/min/μg according to the PCB quintiles of summary measure (P trend <0.001), and this inverse association was consistently observed in all subgroups stratified by age, sex, obesity, type 2 diabetes mellitus, and hypertension, respectively. In vitro experimental studies have also demonstrated that chronic exposure to low-dose POPs could decrease OCR levels.ConclusionThe findings from human and in vitro studies suggest that chronic exposure to low-dose POPs can induce mitochondrial dysfunction by impairing oxidative phosphorylation.

Health risk assessment of exposure to organochlorine pesticides in the general population in Seoul, Korea over 12 years: A cross-sectional epidemiological study

This study evaluated the 12-year trends in serum levels of 28 organochlorine pesticides (OCPs) in 880 adults living in Seoul, Korea. The OCP levels decreased from 2006 to 2017, and p,p′-dichlorodiphenyldichloroethylene was a predominant compound. OCP levels were higher in females than in males, and showed positive associations with BMI and age. The OCP concentrations had inverted U-shaped associations with low-density lipoprotein cholesterol and total cholesterol. Concentrations of β-hexachlorocyclohexane were significantly higher in patients with hypertension than in participants that were normotensive. OCP levels showed positive associations with uric acid, creatinine, and thyroid-stimulating hormone, but negative associations with free thyroxine. Participants with diabetes had significantly higher OCP levels than those without it. Principal component analysis suggested possible differences in disease manifestation depending on the composition of OCPs. These results suggest that OCPs might disturb renal transport and thyroid homeostasis. To our knowledge, the inverted U-shaped associations of heptachlor epoxide and endosulfan with cholesterol, the epidemiological associations of trans-nonachlor and endosulfan with thyroid hormones, and the association of p,p′-DDE with hyperuricemia have not been previously reported in general population. This is the first long-term study to show trends of 28 OCPs in serum and associations with various health indicators in Korea.

Biomonitoring of toxic metals, organochlorine pesticides, and polybrominated biphenyl 153 in Michigan urban anglers

The 32-mile Detroit River and surrounding tributaries have been designated as a Great Lakes Area of Concern due to pollution from decades of municipal and industrial discharges, sewer overflows and urban development. The Agency for Toxic Substances and Disease Registry and the Michigan Department of Health and Human Services conducted a biomonitoring study to assess exposures to persistent toxic substances in Detroit urban shoreline anglers who may be at high exposure risk due to consumption of locally caught fish. Using a modified venue-based sampling approach, 287 adult shoreline anglers along the Detroit River were recruited and participated in the program. Study participants provided blood and urine specimens and completed a questionnaire interview. In this report, we examine percentile estimates for blood lead, blood manganese, urine arsenic, urine mercury, urine cadmium, organochlorine pesticides in serum (mirex, hexachlorobenzene, chlordane), and serum polybrominated biphenyl 153 (PBB 153) concentrations among study participants. Multiple linear regression was used to identify predictors of contaminant concentrations. The Detroit urban anglers' blood lead concentrations were 2 times higher than the general adult U.S. population (median (95% CI): 2.9 μg/dL (1.8–2.3) vs. 0.94 μg/dL (0.90–0.98)). PBB 153 levels were 1.8 times higher than the general adult U.S. population at the 95th percentile (95th percentile, 95% CI: 62.7 ng/g of lipid, 53.2–75.2 vs. 34.6 ng/g of lipid, 12.8–66.8). Percentile estimates of the other study pollutants were similar to background levels found in the general U.S. population. Eating more locally caught fish was not associated with increased body burdens for any of the contaminants examined in this report. Higher blood lead was associated with increased age, male sex, current smoking, residing in a home built before 1960, an annual income less than $25,000, and a work history of lead paint removal. Evidence of PBB exposure in our study cohort likely reflects the continued effect of a widespread contamination of livestock feed in 1973 among Michigan's lower peninsula population. These study results help determine if the pollutants examined warrant further consideration in subsequent population-based biomonitoring of frequent consumers of fish from the Detroit River and surrounding waterways. The biomonitoring data from this study also served to inform public health officials regarding the potential need for environmental public health actions to reduce harmful exposures.

Serum concentrations of organochlorine pesticides, biomarkers of oxidative stress, and risk of breast cancer

Studies have documented that exposure to organochlorine pesticides (OCPs) is linked with breast cancer, but the underlying biological mechanisms are still unknown. This study included 313 women diagnosed with breast cancer and 313 controls in Wuhan, China, and measured 18 OCPs in serum and 3 oxidative stress biomarkers in urine. Multivariable adjusted regression models were used to evaluate the associations among OCPs, oxidative stress biomarkers, and breast cancer. The mediating effect of oxidative stress was assessed by mediation analysis. We observed that most OCPs were positively associated with risk of breast cancer (all FDR-P values < 0.05 or 0.10). Moreover, we found that p,p'-DDT, p,p'-DDD, dieldrin, heptachlor, and heptachlor epoxide were positively associated with 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA) and 8-iso-prostaglandin F2α (8-isoPGF2α), which in turn were positively associated with risk of breast cancer. Mediation analysis indicated that HNE-MA and 8-isoPGF2ɑ mediated the positive associations between these OCPs and risk of breast cancer, with mediating proportion ranging from 6.23% to 19.9%. Our results suggest that lipid peroxidation may mediate the positive associations between OCP exposures and risk of breast cancer.

Adipose to serum ratio and mixtures of persistent organic pollutants in relation to endometriosis: Findings from the ENDO Study

BackgroundEndometriosis is an estrogen-dependent disease. Endocrine disrupting chemicals (EDCs) and their mixtures may play an etiologic role. ObjectivesWe evaluated an adipose-to-serum ratio (ASR) of lipophilic EDCs and their mixtures associated with incident endometriosis. MethodsWe quantified 13 polychlorinated biphenyl (PCB) congeners, 6 polybrominated diphenyl ether (PBDE) congeners, and 11 organochlorine pesticides (OCPs) in serum and omental fat among women from the ENDO Study (2007–2009) aged 18–44 years diagnosed with (n=190) or without (n=283) surgically-visualized incident endometriosis. Odds ratios (OR) and 95% confidence intervals (CI) between ASR and endometriosis were estimated using logistic regression models adjusted for age (years), body mass index (kg/m2), serum cotinine (ng/ml), and breastfeeding conditional on parity. Bayesian hierarchical models (BHM) compared estimated associations for adipose and ASR to serum. Bayesian kernel machine regression (BKMR) estimated change in latent health and 95% posterior intervals (PI) between chemical mixtures and endometriosis. ResultsSelect ASR for estrogenic PCBs and OCPs were associated with an increased odds of an endometriosis diagnosis, but not for anti-estrogenic PCBs or PBDEs. Across all chemicals, BHMs generated ORs that were on average 14% (95% PI: 6%, 22%) higher for adipose and 20% (95% PI: 12%, 29%) higher for ASR in comparison to serum. ORs from BHMs were greater for estrogenic PCBs and OCPs, with no differences for PBDEs. BKMR models comparing the 75th to 25th percentile were moderately associated with endometriosis for estrogenic PCBs [adipose 0.27 (95% PI: 0.18, 0.72) and ASR 0.37 (95% PI: 0.06, 0.80)] and OCPs [adipose 0.17 (95% PI: 0.21, 0.56) and ASR 0.26 (95% PI: 0.05, 0.57)], but not for antiestrogenic PCBs and PBDEs. DiscussionASR added little insight beyond adipose for lipophilic chemicals. BKMR results supported associations between ASR and adipose estrogenic PCB and OCP mixtures and incident endometriosis. These findings underscore the importance of choice of biospecimen and considering mixtures when assessing exposure-disease relationships.

Exposure to Polychlorinated Biphenyls and Organochlorine Pesticides and Risk of Thyroid Cancer in Women

Background: Both polychlorinated biphenyls (PCB) and organochlorine pesticides (OCP) have been associated with thyroid hormone disruption, but their relationship to thyroid cancer is not known. Methods: We investigated the relationship between serum PCB and OCP concentrations and papillary thyroid cancer (PTC) in 250 incident female PTC cases and 250 female controls frequency-matched on age, all residing in Connecticut. Interviews and serum samples were collected from 2010-2013. Samples were analyzed for 32 different chemicals using gas chromatography with isotope dilution high resolution mass spectrometry. We calculated odds ratios (OR) and 95% confidence intervals (CI) using single pollutant logistic regression models for concentrations (per interquartile range) of individual PCB/OCP and summed groups of structurally or biologically similar PCB/OCP, adjusted for education, family history of cancer, alcohol consumption, and body mass index. Sub-analyses included stratification by tumor size (&lt;=1 cm and &gt;1 cm) and birth cohort (born before or in 1960 and born after 1960). We also applied three multi-pollutant approaches (standard multi-pollutant regression, hierarchical Bayesian modeling, principal components regression analysis) to investigate associations with exposures to multiple PCB/OCPs. Results: No PCB/OCPs were positively associated with PTC risk in primary analyses. Statistically significant associations were observed for 9 of the 32 chemicals and 3 summed groups of similar chemicals in the younger birth cohort based on single-pollutant models. Multi-pollutant analyses suggested null associations overall. Conclusions: Our results using single and multi-pollutant modeling do not generally support an association between PCB or OCP exposure and PTC risk, but some associations in the younger birth cohort suggest that additional investigation into early-life exposures and subsequent thyroid cancer risk may be warranted.

Serum Organochlorine Pesticides Level CYP1A1 Genetic Polymorphism &amp; Risk of Prostate Cancer Cases Control Study

Background: Agriculture is the backbone of the economic and social development in the Sudan. 80% of the population depends for their living on agriculture. Organochlorines (OC's) were the first to be used against cotton pests, and control termites in sugarcane. In cancer CYP1A1 have dealt primarily with the metabolic activation of pro-carcinogens including polycyclic aromatic hydrocarbons and estradiol. Aim: The aim of this study is to determine the serum Organochlorine pesticides and PCBs (OC's) level, Cytochrome (CYP) 1A1 genetic polymorphisms and risk for Sudanese prostate cancer patients together with control groups, attending the Wad-Madani teaching hospital, Gezira State- Central Sudan. Method: 100 prostatic cancer patients and 100 controls (over 50 years old) will be studied. A questionnaire will be designed and Clinical examination will be performed including weight and heights. From venous blood (2.5ml) Serum will be separated and store at -80 ОC until analyses. The Organochlorine pesticides residues in serum will be measured by using a modified QuEChERS method by GC/MS. Soil, water and common food samples samples will be collected and storage until the analysis. For CYP1A1 genotyping examination, 2.5 ml of whole blood will be collected in 5 ml EDTA vacutainer tube. Buffy coat separate from plasma and store at -80 ОC until DNA extraction. DNA extraction for blood will be done by QIAamp DNA Mini Kits. PCR Technique will be used for laboratory genetic analysis by using Genotypes Restriction Enzymes Length Polymorphisms (RFLP). Estrogen (E1) level will be analyzed by Elisa technique with Elisa Kits. The study will help to examine one of the most important risk factors for prostate cancer in Sudan (Organochlorine &amp; PCBs pesticides). Find the mutations for Cytochrome P-450 CYP (1A1) genotypes and the relationship between Estrogen (E1) levels and other risk factors.

Exposure to polychlorinated biphenyls and organochlorine pesticides and thyroid cancer in connecticut women

BackgroundThyroid cancer incidence has increased substantially over the past decades, and environmental risk factors have been suggested to play a role. Polychlorinated biphenyls (PCB) and organochlorine pesticides (OCP) are established thyroid hormone disruptors, but their relationship to thyroid cancer is not known. MethodsWe investigated the relationship between serum PCB and OCP concentrations and papillary thyroid cancer (PTC) in 250 incident female PTC cases and 250 female controls frequency-matched on age, all residing in Connecticut. Interviews and serum samples were collected from 2010 to 2013. Samples were analyzed for 32 different chemicals using gas chromatography with isotope dilution high resolution mass spectrometry. We calculated odds ratios (OR) and 95% confidence intervals (CI) using single pollutant logistic regression models for concentrations (per interquartile range) of individual PCB/OCP and summed groups of structurally or biologically similar PCB/OCP, adjusted for education, family history of cancer, alcohol consumption, age, and body mass index. Sub-analyses included stratification by tumor size (≤ and >1 cm) and birth before or during peak PCB production (born in 1960 or earlier and born after 1960), as exposures during early life may be important. We also applied three multi-pollutant approaches (standard multi-pollutant regression, hierarchical Bayesian modeling, principal components regression analysis) to investigate associations with co-exposures to multiple PCB/OCPs. ResultsNo PCB/OCPs were positively associated with PTC in primary analyses. Statistically significant associations were observed for 9 of the 32 chemicals and 3 summed groups of similar chemicals in the those born during peak production based on single-pollutant models. Multi-pollutant analyses suggested null associations overall. ConclusionsOur results using single and multi-pollutant modeling do not generally support an association between PCB or OCP exposure and PTC, but some associations in those born during peak production suggest that additional investigation into early-life exposures and subsequent thyroid cancer risk may be warranted.

Peripubertal serum concentrations of organochlorine pesticides and semen parameters in Russian young men

BackgroundEpidemiologic literature on the relation of organochlorine pesticides (OCPs) with semen quality among adult men has been inconclusive, and no studies have prospectively explored the association between peripubertal serum OCPs and semen parameters in young men. ObjectiveTo evaluate prospective associations of peripubertal serum concentrations of hexachlorobenzene (HCB), β-hexachlorocylohexane (β-HCH), and p,p′-dichlorodiphenyldichloroethylene (p,p′-DDE) with semen parameters among young Russian men. MethodsThis prospective cohort study included 152 young men who enrolled in the Russian Children’s Study (2003–2005) at age 8–9 years and were followed annually until young adulthood. HCB, β-HCH, and p,p′-DDE concentrations were measured at the CDC by mass spectrometry in serum collected at enrollment. Between 18 and 23 years, semen samples (n = 298) were provided for analysis of volume, concentration, and progressive motility; we also calculated total sperm count and total progressive motile count. Linear mixed models were used to examine the longitudinal associations of quartiles of serum HCB, β-HCH and p,p′-DDE with semen parameters, adjusting for total serum lipids, body mass index, smoking, abstinence time and baseline dietary macronutrient intake. ResultsLipid-adjusted medians (IQR) for serum HCB, βHCH and p,ṕ-DDE, respectively, were 150 ng/g lipid (102–243), 172 ng/g lipid (120–257) and 275 ng/g lipid (190–465). In adjusted models, we observed lower ejaculated volume with higher serum concentrations of HCB and βHCH, along with reduced progressive motility with higher concentrations of βHCH andp,ṕ-DDE. Men in the highest quartile of serum HCB had a mean (95% Confidence Interval, CI) ejaculated volume of 2.25 mL (1.89, 2.60), as compared to those in the lowest quartile with a mean (95% CI) of 2.97 mL (2.46, 3.49) (p = 0.03). Also, men in the highest quartile of serum p,ṕ-DDE had a mean (95% CI) progressive motility of 51.1% (48.6, 53.7), as compared to those in the lowest quartile with a mean (95% CI) of 55.1% (51.7, 58.5) (p = 0.07). ConclusionIn this longitudinal Russian cohort study, peripubertal serum concentrations of selected OCPs were associated with lower ejaculated volume and progressive motility highlighting the importance of the peripubertal window when evaluating chemical exposures in relation to semen quality.