New US research has found a connection between chemicals found in common household products and birth defects in rodents.
Carried out by the Edward Via College of Osteopathic Medicine (VCOM) and the Virginia-Maryland College of Veterinary Medicine at Virginia Tech, the team looked at the effects of the chemicals quaternary ammonium compounds, also known as "quats."
Often used as disinfectants and preservatives in everyday household and personal products such as cleaners, laundry detergent, fabric softener, shampoo and conditioner, and eye drops, most people are exposed to the chemicals on a daily basis in the home, hospitals, public spaces, and swimming pools.
The research focused in specifically on two commonly used quats: alkyl dimethyl benzyl ammonium chloride and didecyl dimethyl ammonium chloride, used for their antimicrobial and antistatic properties and often listed on the ingredient lists as ADBAC and DDAC, respectively.
The researchers found that mice and rats were exposed to these chemicals gave birth to offspring with neural tube birth defects -- the same birth defect as spina bifida and anencephaly in humans. The animals also did not need to be given the chemicals for the birth defects to occur, simply being in a room that had been cleaned with quat-based products was enough.
In addition, the team also found that birth defects not only occurred when both parents were exposed to chemicals, but also when just one parent was exposed, with an increased risk of birth defects also found two generations after stopping exposure.
"The fact that birth defects could be seen when only the father was exposed means that we need to expand our scope of prenatal care to include the father," suggested Terry Hrubec, the study's first author.
The findings support an earlier study by Hrubec, which suggested that the use of quats leads to a reproductive decline in mice, decreasing sperm count in males and ovulation in females.
The team believes that quats could also be causing similar problems in humans, possibly contributing to the rise in infertility, which has increased in recent decades.
"We are asked all of the time, 'You see your results in mice. How do you know that it's toxic in humans?'" Hrubec said. "Our research on mice and rats shows that these chemicals affect the embryonic development of these animals. Since rodent research is the gold standard in the biomedical sciences, this raises a big red flag that these chemicals may be toxic to humans as well."
Hrubec now suggests further research could help to determine whether those who have a higher rate of exposure to quats, such as healthcare workers or restaurant staff, also have more difficulty becoming pregnant or have a greater risk of having children with neural tube birth defects.