*Exposure in pregnancy causes altered brain development, male infertility in future generations
*90% of popular brands including Aquafina, Nestle Pure Life contained tiny pieces, says WHO
More reasons have emerged why Nigerians should stop using plastics to package food and water.
The World Health Organisation (WHO) had just released the results of a recent analysis of some of the world’s most popular bottled water brands, discovering that more than 90 per cent contained tiny pieces of plastic. A previous study also found high levels of microplastics in tap water.
The worrying findings prompted WHO to launch a probe into the potential health risks of plastic in drinking water.The study tested 259 bottles from 11 brands, including Aquafina, Evian, Dasani, Nestle Pure Life and San Pelligrino, purchased from 19 locations in nine different countries. It found an average of 325 plastic particles for every litre of water being sold.
Of the 259 bottles tested in total, only 17 were free of plastics, according to the study.But new research in mice provides an explanation for how exposure to the widely used chemical bisphenol A (BPA) during pregnancy, even at levels lower than the regulated “safe” human exposure level, can lead to altered brain development and behavior later in life.
The research was presented Monday, March 19 at ENDO 2018, the 100th annual meeting of the Endocrine Society in Chicago, Ill, United States (U.S.).BPA is a chemical that is added to many commercial products, including water bottles, paper receipts, can liners and food storage containers. It is known as an endocrine-disrupting chemical — a chemical that interferes with the body’s hormones.
“Decades of research in over 1,000 animal and 100 human epidemiological studies have demonstrated a link between BPA exposure and adverse health outcomes,” said lead researcher Deborah Kurrasch, Ph.D., Associate Professor at the University of Calgary in Calgary, Canada. “This is especially true for the developing brain, which is particularly sensitive to the estrogen-promoting effects of BPA during gestation. Indeed, several human studies have now correlated early life BPA exposure with behavioral problems later in childhood, suggesting BPA permanently alters brain development that leads to lasting effects on neural functioning.”
Governmental agencies around the world, including the U.S. Food and Drug Administration, Health Canada, and European Food Safety Authority, declare BPA to be safe. “One reason for this disparity is the absence of a smoking gun: if BPA is so toxic to developing brains, then where is the evidence of defective brains?” Kurrasch said. “Our study is the first to use environmentally relevant doses of BPA and show exposure to the chemical during brain development can affect the timing of the birth of nerve cells, or neurons.”
Also, a new study in mice suggests that chemicals found in a variety of routinely used consumer products may be contributing to the substantial drop in sperm counts and sperm quality among men in recent decades.
The study found the effect of chemicals that disrupt the body’s hormones, called endocrine-disrupting chemicals, may extend beyond more than one generation. The research results will be presented Monday, March 19, at ENDO 2018, the 100th annual meeting of the Endocrine Society, in Chicago, Ill.
“Sperm counts among men have dropped substantially over the last few decades, but the reason for such an alarming phenomenon is not known. These results suggest that when a mother is exposed to an endocrine disruptor during pregnancy, her son and the son’s future generations may suffer from decreased fertility or hormone insufficiency,” said lead author Radwa Barakat, B.V.S.C., M.Sc., of the College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Ill.
The researchers studied the effect of di-(2-ethylhexyl) phthalate (DEHP), which is among the most widely used endocrine-disrupting chemicals. It is found in a wide array of industrial and consumer products, including polyvinyl chloride (PVC) piping and tubing, cosmetics, medical devices and plastic toys. The study found that male mice exposed to DEHP prenatally had significantly less testosterone in their blood and fewer sperm in their semen. Consequently, they lost fertility at an age when they normally would have been fertile.
“Most surprisingly, the male mice born to male mice that were exposed to DEHP also exhibited similar reproductive abnormalities — indicating prenatal exposure to DEHP can affect the fertility and reproductive capacity of more than one generation of offspring,” Barakat said. “Therefore, DEHP may be a contributing factor to the decreased sperm counts and qualities in modern men compared to previous generations.”Barakat and colleagues gave pregnant mice one of four doses of DEHP, or a type of corn oil, from 11 days after they conceived until birth.
Adult males born to these mice were bred with unexposed female mice, to produce a second generation of mice. Young adult males from this second generation were bred with unexposed females to produce a third generation. When each generation of mice was 15 months old, the researchers measured sex hormone levels, sperm concentrations and sperm motility, or movement (a potential sign of infertility).
In second-generation males, only those descended from mice in the highest DEHP exposure group had abnormal reproductive results — lower testosterone concentration, sperms levels and sperm motility. Third-generation males descended from DEHP-exposed mice also exhibited reproductive abnormalities at age 15 months, even those descended from mice that received a lower dose of the chemical. The researchers were surprised to find that the lowest DEHP dose group exhibited the greatest abnormalities.
“This study underscores the importance of educating public to try their best effort to reduce their exposure to this chemical and also the need to substitute this chemical with a safer one,” Barakat said.