Academic journal article Environmental Health Perspectives

Low Dose of Some Persistent Organic Pollutants Predicts Type 2 Diabetes: A Nested Case-Control Study

Academic journal article Environmental Health Perspectives

Low Dose of Some Persistent Organic Pollutants Predicts Type 2 Diabetes: A Nested Case-Control Study

Article excerpt

BACKGROUND: Low doses of some persistent organic pollutants (POPs) associate cross-sectionally with type 2 diabetes, whereas associations with high POP exposures are inconsistent.

OBJECTIVES: We investigated whether several POPs prospectively predict type 2 diabetes within the Coronary Artery Risk Development in Young Adults (CARDIA) cohort.

METHODS: Participants in this nested case--control study were diabetes free in 1987-1988. By 2005-2006, the 90 controls remained free of diabetes, whereas the 90 cases developed diabetes. Using serum collected in 1987-1988, we measured 8 organochlorine pesticides, 22 polychlorinated biphenyl congeners (PCBs), and 1 polybrominated biphenyl (PBB). We compared POP concentrations from CARDIA and the National Health and Nutrition Examination Survey (NHANES) in 2003-2004. We computed odds ratios (ORs) for incident diabetes using logistic regression analysis.

RESULTS: Chlorinated POPs in CARDIA in 1987-1988 were much higher than corresponding NHANES 2003-2004 concentrations. POPs showed nonlinear associations with diabetes risk. The highest risk was observed in the second quartiles of trans-nonachlor, oxychlordane, mirex, highly chlorinated PCBs, and PBB 153--a finding that suggests low-dose effects. We concentrated risk by summing these POPs and isolated very low concentrations of multiple POPs in the lowest sextile of the sum. The adjusted OR in the second sextile vs. the lowest sextile was 5.3 overall and 20.1 for body mass index [greater than or equal to] 30 kg/[m.sup.2].

CONCLUSIONS: Several POPs at low doses similar to current exposure levels may increase diabetes risk, possibly through endocrine disruption. Certain POPs may a play a role in the current epidemic of diabetes, which has been attributed to obesity.

KEY WORDS: diabetes, obesity, organochlorine pesticides, persistent organic pollutants, polychlorinated biphenyls. Environ Health Perspect 118:1235-1242 (2010). doi:10.1289/ehp.090l480 [Online 5 May 2010]

**********

Persistent organic pollutants (POPs) are a group of chemicals with common properties such as persistence, lipophilicity, and biomagnification in the food chain (Li et al. 2006). Lee et al. (2006b, 2007c) recently reported that serum concentrations of POPs were strongly associated with the prevalence of type 2 diabetes in the U.S. general population; this association was stronger among obese persons than among nonobese persons. Although dioxins have been widely studied as the most toxic chemical among POPs, organochlorine (OC) pesticides and polychlorinated biphenyl (PCB) congeners, not dioxins, were strongly associated with type 2 diabetes. In particular, it was striking that when POPs concentrations were very low, prevalent type 2 diabetes was rare even among obese persons [body mass index (BMI) [greater than or equal to] 30 kg/[m.sup.2]]. Serum concentrations of these POPs were also associated with insulin resistance and adverse lipid profiles (Lee et al. 2007a, 2007b). Xenobiotics mainly bioaccumulate in adipose tissue; thus, all these findings raise the possibility that some POPs are critically involved in the pathogenesis of type 2 diabetes (Lee et al. 2006a). However, because all these studies were cross-sectional, reverse causality, in which diabetes enhances POPs accumulation or inhibits their clearance, cannot be ruled out.

One recent study of a cohort of 471 Great Lakes sport fish consumers identified 36 incident cases of type 2 diabetes during follow-up examinations and demonstrated an association of incident diabetes with serum concentrations of 2,2-bis(4-chlorophenyl)-1,1-dichloroethene (p, p' -DDE), but not PCBs (Turyk et al. 2009). However, several prospective studies of selected POPS performed in occupational or accidental high-exposure settings reported inconsistent results, particularly for 2,3,7,8-tetrachloro-dibenzo-p-dioxin (2,3,7,8-TCDD) (Henriksen et al. 1997; Longnecker and Michalek 2000; Steenland et al. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.