Using mice, researchers discovered BPA exposure during pregnancy increased the risk of allergic asthma in offspring.
Because BPA is such a common contaminant, it is important to understand the risk of exposure, especially during pregnancy.
"Use water bottles that are marked as BPA free."
The study was led by Dr.Yoichi Nakajima from the Fujita Health University along with researchers from the Departments of Pediatrics and Biochemistry and Molecular Biology at The University of Texas Medical Branch. Researchers exposed mice to BPA one week before pregnancy until the end of the study.
BPA may affect asthma risk because, during pregnancy, infants have not developed BPA-metabolizing enzymes.
BPA is an organic compound that is used to make plastics. Because it is not very soluble in water, it can be found for a long time in the environment. Since BPA can be commonly found, researchers believe the increase of asthma cases in children is due to this environmental exposure to BPA.
Mice were given 10 micrograms of BPA one week before pregnancy until the end of the study. Some of the offspring were given to mice who were not exposed to BPA. Some offspring of non-exposed mice were given to BPA-exposed mice.
The offspring were then exposed to ovalbumin, which is a protein found in egg whites and is used to test allergy sensitivity.
The offspring of mice who were exposed to BPA in utero were found to develop asthma symptoms in response to the allergen exposure. Possible exposure to BPA via breast milk did not increase the risk of developing asthma.
Researchers believed this increased sensitivity to BPA in utero is because fetuses do not develop the enzyme that metabolizes BPA until after they are born. In the study, the mice offspring did not develop the enzyme until day five and reached adult levels at day 25.
While this study was conducted with mice, previous studies have shown a link between BPA exposure during pregnancy and childhood wheeze. Future studies can involve humans to better understand how much of an impact BPA exposure has on the development of asthma. For now, pregnant women should be careful and monitor their BPA exposure.
Funding was provided by grants from the National Institute of Environmental Health Science (NIEHS), NIEHS Center and the National Center for Research Resources. No author conflicts were reported.
This study was published in the February edition of Environmental Health.