Phthalates are organic pollutants widely present in the environment due to their extensive use, particularly in the plastic industry. Sakina Mhaouty-Kodja's team has shown that chronic exposure of adult female mice to low doses of phthalates - close to the environmental exposure - alters the natural olfactory preference of females towards males, reduces the attractiveness of females and inhibits lordosis behaviour (the posture adopted by females during mating). These changes are associated with a reduced number of neurons expressing the progesterone receptor in the key brain regions underlying the expression of female sexual behaviour. The results show that females are more vulnerable than males to environmental exposure to phthalates, suggesting a major impact on reproduction in rodents and potentially other species with similar neuroendocrine regulatory systems.

These results, published in the journal Environmental Health Perspectives, were the subject of a news item on the INSB and CNRS Délégation Paris-Centre websites.

© Sakina Mhaouty-Kodja

Figure: Chronic oral exposure of female mice to phthalates through contaminated food reduces the expression of the progesterone receptor (PR) in the brain, as well as olfactory preference, attractiveness and lordosis posture necessary for mating.

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¹Equipe Neuroplasticité des Comportements de Reproduction

²Exposure of adult female mice to low doses of di(2-ethylhexyl) phthalate alone or in an environmental phthalate mixture: Evaluation of reproductive behavior and underlying neural mechanisms.Adam N, Brusamonti L, Mhaouty-Kodja S
Environ Health Perspect, 27 Janvier 2021. https://doi.org/10.1289/EHP7662