Increased maternal butylparaben exposure elevates risk of asthma: Study

A recent study published in the Environmental Pollution journal highlighted how prenatal exposure to certain chemicals, commonly found in everyday products, may contribute to asthma development in children. This study analyzed the effects of maternal urinary phenol concentrations during early pregnancy on childhood asthma risk at age four.

The research examined a total of 3,513 mother-child pairs enrolled in the Japan Environment and Children's Study (JECS) Sub-Cohort Study. Maternal urine samples, collected during the first trimester of pregnancy, were tested for 24 types of phenols, including parabens, bisphenol A, octylphenol, and nonylphenol. Also, phenol levels varied widely among participants. One key finding was that methylparaben was present at high concentrations in almost all samples, with an average level of 267.7 ng/ml and a large variation across individuals.

The analysis revealed significant associations between prenatal exposure to certain phenols and the risk of asthma in children. High levels of butylparaben in maternal urine were linked to a 54% increase in the odds of asthma onset by age four. Meanwhile, exposure to 4-nonylphenol showed a gender-specific effect where the boys born to mothers with detectable levels of this compound had more than double the odds of developing asthma (odds ratio: 2.09), and the girls showed no significant increase in risk.

These findings underline the complexity of phenol exposure and its potential to impact children's health differently based on gender and chemical type. While the mechanisms remain unclear, the results indicate that certain phenols act as endocrine disruptors, possibly influencing respiratory health through hormonal pathways.

The study provides a crucial step toward understanding the risks of prenatal chemical exposure. Given that many of these phenols are widely used in consumer products, the findings emphasize the need for increased awareness and potential regulation to minimize exposure during pregnancy. And so, avoiding products containing butylparaben or nonylphenol during pregnancy might help reduce the risk of asthma in children.

Overall, these findings will inspire further studies to investigate the biological pathways involved and inform future public health guidelines to protect vulnerable populations, particularly pregnant women and children.

Reference:

Kuraoka, S., Oda, M., Ohba, T., Mitsubuchi, H., Nakamura, K., Katoh, T., Kamijima, M., Yamazaki, S., Ohya, Y., Kishi, R., Yaegashi, N., Hashimoto, K., Mori, C., Ito, S., Yamagata, Z., Inadera, H., Nakayama, T., Sobue, T., Shima, M., … Katoh, T. (2024). Association of phenol exposure during pregnancy and asthma development in children: The Japan Environment and Children’s study. In Environmental Pollution (Vol. 361, p. 124801). Elsevier BV. https://doi.org/10.1016/j.envpol.2024.124801