Triclosan and other compounds widely used in cosmetics, toothpaste, soap and other consumer products may disrupt boys' growth during their fetal period and first years of life, according to a new study conducted by a consortium of U.S. and European agencies.
Colgate toothpaste was widely criticized last month for continuing to use triclosan and the U.S. Food and Drug Administration (FDA) warned in August that compounds used in antibacterial soap are dangerous to pregnant women and their unborn children.
The compounds implicated in the latest study are all phenols and, besides triclosan, include parabens, used in cosmetics; benzopherone-3, used as a UV filter in sun protection products; and dichlorophenols, used in indoor deodorizers.
Another widely-used phenol, bisphenol A, did not appear to affect fetal growth.
The study was based on 520 boys from the EDEN mother-child cohort. Pregnant women participating in this cohort were recruited in Europe between 2003 and 2006. Growth of each child was assessed by ultrasound during pregnancy, and by measuring weight and length/height from birth to the age of 3 years.
A urine sample taken during pregnancy allowed measurement of biomarkers for exposure to phenols in the CDC Environmental Health Laboratory for U.S. biosurveillance programs.
Results show that over 95% of the pregnant women were exposed to these substances, and that maternal exposure to some phenols may disrupt the growth of boys. More specifically, the researchers showed a negative correlation between triclosan levels and growth parameters measured at the ultrasound examination in the third trimester of pregnancy, and that parabens were associated with increased weight at birth and at three years.
It is known that accelerated growth in the first years of life may increase the risk of obesity in later childhood. The study did not identify any clear link between urinary concentrations of other phenols and ante- and postnatal growth of boys.
"This is the first study concerning these environmental contaminants based on growth data collected during pregnancy, at birth, and up to the age of three years," the researchers said. Previous studies were focused on just one of these periods, and were usually restricted to the study of bisphenol A, without including other phenols.
Concern on bisphenol-A has abated following an EPA-funded 2013 study by Justin Teeguarden, a senior research scientist at the Department of Energy laboratory in Richland, Wash.
Teeguarden said the levels he found were "thousands of times lower" than levels that cause health effects, lending support to industry arguments that human exposure to BPA is so slight that it is inconsequential and that the public health benefit of BPA usage in canned foods is so significant it outweighs any slight risk from minimal exposure to the substance.