Multiple exposure of children to endocrine disruptors revealed by hair analysis
Many chemicals contained in daily-used hygiene and cleaning products or used in agriculture can act as endocrine disruptors, inducing health adverse effects associated with the impairment of the body’s hormone balance. The Human Biomonitoring Research Unit of LIH’s Department of Population Health carried out a study on the exposure of children to a range of known endocrine disruptors using hair samples as biomonitoring matrix.
The laboratory was entrusted with this study by the weekly French newsmagazine L’Obs, which published the results in a special dossier in November 2015. Hair samples from a panel of 63 children aged between 0 and 12 years were collected, 43 of them living in Paris or its suburbs and 20 in a rural area in Eure-et-Loire. With chromatography and mass-spectrometry-based methods developed by the laboratory, the samples were tested for the presence of 69 endocrine disruptors belonging to different chemical families.
The study revealed that children from urban and rural areas are almost equally exposed to multiple endocrine disruptors. On average, children’s hair contained 20.2 of the tested compounds, and the sample from the most exposed subject comprised even 35. The most frequently detected substances were derived from herbicides (trifluralin, oxadiazon), fungicides (hexachlorobenzene, 4-nitrophenol) and insecticides (dimethylthiophosphate, permethrin, 3-phenoxybenzoic acid, endosulfan). Whereas the geographical location did not have any significant impact, small gender differences were observed. Boys were found to be more exposed (21 molecules on average) compared to girls (18.5 molecules). Also, children below 4 years (22 molecules) appeared to be slightly more affected than school-aged children (20 molecules).
Dr Brice Appenzeller, head of the Human Biomonitoring Research Unit comments these results: “Endocrine disruptors can interfere with the hormone balance at multiple levels. They can disrupt the synthesis, secretion, transport, binding, action or elimination of hormones and thus impair homeostasis and development. In children, this can have long-term consequences on intelligence, behaviour, fertility and cardiometabolic health’, he states.
Endocrine disruptors can be found almost everywhere. ‘Some of these chemicals are used as preservative in soaps, skin creams and detergents or as disinfectants in cosmetics, others as softeners for plastics, as insecticides or agricultural pesticides, and also as anti-stain or anti-adhesive products’, explains Dr Appenzeller. ‘Exposure can be limited, for example by a conscious consumer behaviour, but not completed avoided.’
Strikingly, the effect is not always dose-dependent. A small dose can have the reverse effect of a larger one, and substances that do not have any significant effect singly, can act as endocrine disruptors when present simultaneously in the body by having a so-called cocktail effect.
Link to article (in French): http://tempsreel.nouvelobs.com/sante/20151027.OBS8437/enquete-votre-enfant-est-il-pollue.html