Phthalates found in common consumer products increased risk for diabetes in women
Women with a higher concentration of phthalate metabolites in their urine were almost twice as likely to report a diabetes diagnosis compared with women with lower levels, according to researchers.
Phthalates are among the group of chemicals commonly labeled as “endocrine disrupters,” which can be found in common personal care products such as moisturizers, nail polish, soap, hair spray, perfume, electronics and toys. They can also be found in adhesives, medications and medical devices, including IV bags and tubing.
Using data from the National Health and Nutrition Examination Survey 2001-2008, Tamarra James-Todd, PhD, of the division of women’s health at the Connors Center for Women’s Health and Gender Biology, Brigham and Women’s Hospital and Harvard Medical School, and colleagues examined CDC-analyzed urinary concentrations of phthalate metabolites and self-reported diabetes in 2,350 women.
Phthalate metabolites were measured in a random, one-third subsample of NHANES patients with urine measurements, the researchers wrote.
The association of diabetes was estimated with concentrations of mono-ethyl phthalate (MEP), mono-n-butyl phthalate (MnBP), mono-isobutyl phthalate (MiBP), mono-benzyl phthalate (MBzP), mono-(3-carboxypropyl) phthalate (MCPP), and the sum of three di-2-ethylhexyl phthalate (DEHP) metabolites: mono-(2-ethyl-hexyl) phthalate (MEHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono-(2-ethyl5-oxohexyl) phthalate (MEOHP).
Exposure to phthalates was classified using quartiles based on the overall population phthalate levels. Patients were classified as having diabetes if they responded “yes” to the question: Other than during pregnancy, have you ever been told by a doctor or health professional that you have diabetes or sugar diabetes?
In addition, data on fasting blood glucose and fasting insulin levels were available from women randomly assigned to a morning fast. However, HbA1c levels were available for the entire study population.
James-Todd and colleagues adjusted for sociodemographic and behavioral factors, including dietary factors such as total caloric and fat intake, they wrote. Further adjustments were made for BMI and waist circumference.
Once adjustments were made, women with higher levels of MnBP, MiBP, MBzP, MCPP and the sum of three DEHP had an increased risk for diabetes vs. women who displayed the lowest levels of phthalates.
“In women without self-reported diabetes, MiBP was positively associated with [fasting blood glucose], and MiBP and the sum of DEHP were positively associated with [homeostatic model assessment-insulin resistance]. No associations were present for urinary phthalate metabolites and HbA1c levels,” the researchers wrote.
The strongest association was seen among women in the highest quartile for MBzP (OR=1.96; 95% CI, 1.11-3.47) and MiBP (OR=1.95; 95% CI, 0.99-3.85), who had almost twice the odds of diabetes.
The researchers said further research is warranted to determine causal links between diabetes and phthalates.
Disclosure: The researchers report no relevant financial disclosures.