Children whose mothers were exposed to phthalates during pregnancy have a higher risk of experiencing allergic asthma than children whose mothers were not, according to the findings of a new study.
German researchers determined exposure to the phthalate benzylbgutylphthalate (BBP) during pregnancy can affect a child’s likelihood of having allergic asthma. This effect was seen up to two generations later, according to findings published on May 3 in the Journal of Allergy and Clinical Immunology.
Phthalates are plasticizers used to make plastics flexible. On a daily basis, humans regularly come into contact with phthalates through food packaging, plastic bottles, detergents, nail polish, hair spray, dryer sheets, and even children’s toys. The chemicals can easily enter the system through the skin, ingestion or dust inhalation.
Researchers measured phthalate exposure in the urine of pregnant women from the LINA study (Lifestyle and environmental factors and their Influence on the Newborn Allergy-risk). The study focuses on mother-child pairs.
The findings indicate that phthalate concentrations were directly correlated with the occurrence of allergic asthma among children. More so, the higher concentrations of BBP in mothers’ urine resulted in a higher risk of the presence of allergic asthma in the children.
Researchers then compared this study to a mouse study focusing on the same things. They found the mouse model also linked phthalate concentrations to increased risk of allergic asthma in offspring, even among third generation mice.
There were no increased allergic symptoms among adult mice. Researchers said this indicated the exposure timeframe was key. Infants exposed during early stages of development face a higher risk of effects.
The mouse study helped researchers determine that gene methylation occurred in the DNA, effectively “switching off” methyl groups and causing the allergic effect. They then determined the same effect was occurring in the human study.
Prior studies have indicated phthalate exposure during pregnancy may decrease a child’s intelligence. Women with the highest urine levels of phthalates were more likely to give birth to children who scored lower on intelligence tests later.
The newest research indicates that phthalates have an effect on the immune system. Yet, other studies have provided links between the ubiquitous chemical and metabolism, increasing the risk of obesity, as well as increased risk of high blood pressure.