The association between environmental exposures to chlordanes, adiposity and diabetes-related features: a systematic review and meta-analysis

Abstract

Chlordane compounds (CHLs) are components of technical chlordane listed in the Stockholm convention on persistent organic pollutants identified as endocrine disrupting chemicals (EDCs) and may interfere with hormone biosynthesis, metabolism or action resulting in an unbalanced hormonal function. There is increasing scientific evidence showing EDCs as risk factors in the pathogenesis and development of obesity and obesity-related metabolic syndromes such as type 2 diabetes, but there is no systematized information on the effect of CHLs in humans. Our aim is to identify the epidemiological data on the association between CHLs with adiposity and diabetes using a systematic approach to identify the available data and summarizing the results through meta-analysis. We searched PubMed and Web of Science from inception up to 15 February 2021, to retrieve original data on the association between chlordanes, and adiposity or diabetes. For adiposity, regression coefficients and Pearson or Spearman correlation coefficients were extracted and converted into standardized regression coefficients. Data were combined using fixed effects meta-analyses to compute summary regression coefficients and corresponding 95% confidence intervals (95% CI). For the association between chlordanes and diabetes, Odds ratios (ORs) were extracted and the DerSimonian and Laird method was used to compute summary estimates and respective 95% CI. For both, adjusted estimates were preferred, whenever available. Among 31 eligible studies, mostly using a cross-sectional approach, the meta-analysis for adiposity was possible only for oxychlordane and transchlordane, none of them were significantly associated with adiposity [(β = 0.04, 95% CI 0.00; 0.07, I2 = 89.7%)] and (β = 0.02, 95% CI − 0.01; 0.06), respectively. For diabetes, the estimates were positive for all compounds but statistically significant for oxychlordane [OR = 1.96 (95% CI 1.19; 3.23)]; for trans-nonachlor [OR = 2.43 (95% CI 1.64; 3.62)] and for heptachlor epoxide [OR = 1.88 (95% CI 1.42; 2.49)]. Our results support that among adults, the odds of having diabetes significantly increase with increasing levels of chlordanes. The data did not allow to reach a clear conclusion regarding the association with adiposity.

Contribution of Bayesian Networks to Environmental Health Issues, Application to Etang de Berre

“…Usually, a space in the "countryside" is selected. Now, the endocrine disruptors to which the population can be exposed via pesticides can induce the same pathologies (diabetes) [35,36], which could confuse the "control cases" comparisons, since we might end up with high diabetes rates on both sides.…”

Alterations of Systemic and Hepatic Metabolic Function Following Exposure to Trans-nonachlor in Low and High Fat Diet Fed Male Sprague Dawley Rats

“…8,9 Recent review of the epidemiological studies examining the association between POPs exposure and diabetes by a panel assembled by the National Toxicology Program determined the strongest positive associations between POPs exposures and diabetes existed for OC pesticides, especially DDE and trans-nonachlor, and polychlorinated biphenyls (PCBs). 10 To further strengthen this association, a recent meta-analysis performed by Mendes et al (2021) demonstrated a significant positive association between both oxychlordane and trans-nonachlor and diabetes-related features such as fasting blood glucose, homeostatic model assessment for insulin resistance (HOMA-IR), or hemoglobin A1c (HbA1c). 11 Recent animal studies have revealed that exposure to an environmentally relevant mixture of OC compounds, including OC pesticides (DDE, trans-nonachlor, and oxychlordane among others with DDE being the most prevalent) and PCBs, in contaminated salmon oil promotes the development of T2D, including hyperglycemia, hyperinsulinemia, and dyslipidemia, in high fat or western diet fed animals.…”

“…10 To further strengthen this association, a recent meta-analysis performed by Mendes et al (2021) demonstrated a significant positive association between both oxychlordane and trans-nonachlor and diabetes-related features such as fasting blood glucose, homeostatic model assessment for insulin resistance (HOMA-IR), or hemoglobin A1c (HbA1c). 11 Recent animal studies have revealed that exposure to an environmentally relevant mixture of OC compounds, including OC pesticides (DDE, trans-nonachlor, and oxychlordane among others with DDE being the most prevalent) and PCBs, in contaminated salmon oil promotes the development of T2D, including hyperglycemia, hyperinsulinemia, and dyslipidemia, in high fat or western diet fed animals. 12,13 This effect of contaminated salmon oil was eliminated upon refinement or decreasing the POPs load in the salmon oil.…”

“…10 To further strengthen this association, a recent meta-analysis performed by Mendes et al (2021) demonstrated a significant positive association between both oxychlordane and trans-nonachlor and diabetes-related features such as fasting blood glucose, homeostatic model assessment for insulin resistance (HOMA-IR), or hemoglobin A1c (HbA1c). 11…”

Partitioning of Persistent Organic Pollutants between Adipose Tissue and Serum in Human Studies

“…In addition, other classes, like polybrominated diphenyl ethers (PBDE) used as additive flame retardants, are among the substances of emerging concern [ 2 ]. Some POPs have shown the capacity for interacting with and disrupting a variety of molecular pathways, triggering pathogenic processes involved in human health, including impaired reproduction [ 7 , 8 ], carcinogenesis [ 9 , 10 ] or metabolic dysregulation [ 11 , 12 ], among others. Experimental and epidemiological studies on POPs have mainly relied on the effects of a few individual congeners, whereas the effect of low-dose mixtures of POPs resembling realistic background exposures remains scarcely explored [ 13 ].…”