New York, Dec 23 (IANS) Exposure to a common plastic compound found in baby bottles and personal care products may increase the risk of pregnant women and lactating mothers developing negative behavioural changes and impairment in brain regions, researchers have warned.

The study, conducted in mice, showed that the exposure to bisphenol S (BPS) -- a replacement chemical for Bisphenol A (BPA) -- impaired the maternal care of pups, including mothers' ability to adjust to the needs of their young during early development. 

"BPS affects maternal behaviour as well as maternally relevant neural correlates," said Mary Catanese, doctoral student at the University of Massachusetts - Amherst. 

The effects differ based on dose, postpartum period and generational timing of exposure, Catanese said.

Further, BPS exposure was found to increase the infanticide thoughts in a brain region sensitive to estrogen or estrogen-mimicking chemicals as well as important in maternal behaviour in mice. 

"Although these same effects were not seen at the higher dose, more than 10 per cent of females exposed to two microgram BPS/kg per day either killed their pups or provided such poor instrumental maternal care that one or more pups needed to be euthanised. 

While not statistically significant, the neglect and poor maternal care we observed were striking," explained Laura Vandenberg, assistant professor at the University of Massachusetts.

In addition, BPS exposure may also impair a mother to adjust to the changing needs of her pups, the researchers observed.

BPS-exposed mothers showed significantly shorter latency to retrieve their first pup and significantly shorter latency to retrieve their entire litter, which may not represent improved care but instead "may indicate hyperactivity, compulsivity-like behaviour, heightened stress response to scattered pups, or a displaced form of retrieval," Vandenberg noted.

The details of the study appeared in the journal Endocrinology.