The following is excerpted from an online article posted by ScienceAlert.
A search for chemicals that could inadvertently activate parts of the brain responsible for reproductive functions has identified compounds many of us may encounter in our environment, highlighting a potential trigger for early puberty in women.
One is a musky scent, once commonly used in men’s fragrances, which was banned by the European Union, yet might still be found in products sold across much of the world, including the US.
Over the past century, the average ages of menarche – the commencement of menstruation – and breast development have trended downward. While there are clear racial and socioeconomic factors, the phenomenon is too global and too rapid to be wholly genetic, leaving scientists to question what novel environmental factors might cause such early changes.
While plenty of studies have hunted for candidates that could account for such precocious maturity, inconsistent results have made it hard to pin down any culprits.
Researchers from the US National Institutes of Health and North Western University chose to focus their search around a network of neurons in the hypothalamus known to play a critical role in managing the onset of puberty.
Rather than search for signs of disruption in a sample of volunteers, the researchers used a culture of tissue grown in the lab to screen for the effects of various substances on the cells’ GnRH and kisspeptin activity.
The screening itself was substantial, sorting through some 10,000 different substances, outlined in an Environmental Protection Agency library. Then, additional evaluation tools whittled the list down to a few dozen compounds that interfered with one or both of the pathways.
One compound in particular stood out – a candidate agonist for kisspeptin, called musk ambrette. Once commonly found in cosmetics and men’s fragrances, the sweet, slightly animal scent was banned by the European Union in the 1990s, following evidence of its neurotoxicity in rats, though it continues to be synthesized in India and China.
The substance is less common in commercial products today, thanks to recommendations by the International Fragrance Association. But being resistant to degradation, it continues to have an environmental presence that could pose a serious, ongoing concern, warn studies such as this new one.
This research was published in Endocrinology.
Source: ScienceAlert
https://www.sciencealert.com/fragrance-in-care-products-could-be-triggering-early-puberty-in-girls