New York City children exposed in the womb to moderate levels of two plasticizers had a 72 to 78 percent higher chance of developing asthma, according to a new study published in Environ Health Perspectives.
The study is the first to link childhood asthma, which has been increasing in recent decades, to prenatal exposure to phthalates.
“These results suggest that phthalates may be one of the factors associated with that increase,” said Robin Whyatt, a Columbia University environmental health scientist who led the study. She added, however, that more studies are needed to understand how important a risk factor these chemicals may be.
Phthalates, used in the manufacture of vinyl and some cosmetics, have been connected to a number of health effects in lab animal and human studies, including airway inflammation, altered male genitalia, attention and learning problems and premature births.
2014 Study Abstract
Studies suggest that phthalate exposures may adversely affect child respiratory health.
We evaluated associations between asthma diagnosed in children between 5 and 11 years of age and prenatal exposures to butylbenzyl phthalate (BBzP), di-n-butyl phthalate (DnBP), di(2-ethylhexyl) phthalate (DEHP), and diethyl phthalate (DEP).
Phthalate metabolites were measured in spot urine collected from 300 pregnant inner-city women. Children were examined by an allergist or pulmonologist based on the first parental report of wheeze, other respiratory symptoms, and/or use of asthma rescue/controller medication in the preceding 12 months on repeat follow-up questionnaires. Standardized diagnostic criteria were used to classify these children as either having or not having current asthma at the time of the physician examination. Children without any report of wheeze or the other asthma-like symptoms were classified as nonasthmatics at the time of the last negative questionnaire. Modified Poisson regression analyses were used to estimate relative risks (RR) controlling for specific gravity and potential confounders.
Of 300 children, 154 (51%) were examined by a physician because of reports of wheeze, other asthma-like symptoms, and/or medication use; 94 were diagnosed with current asthma and 60 without current asthma. The remaining 146 children were classified as nonasthmatic. Compared with levels in nonasthmatics, prenatal metabolites of BBzP and DnBP were associated with a history of asthma-like symptoms (p < 0.05) and with the diagnosis of current asthma: RR = 1.17 (95% CI: 1.01, 1.35) and RR = 1.25 (95% CI: 1.04, 1.51) per natural log-unit increase, respectively. Risk of current asthma was > 70% higher among children with maternal prenatal BBzP and DnBP metabolite concentrations in the third versus the first tertile.
Prenatal exposure to BBzP and DnBP may increase the risk of asthma among inner-city children. However, because this is the first such finding, results require replication.
Sources and More Information:
- Asthma in Inner-City Children at 5-11 Years of Age and Prenatal Exposure to Phthalates: The Columbia Center for Children’s Environmental Health Cohort, Environ Health Perspect; DOI:10.1289/ehp.1307670, 17 September 2014. PDF and Supplemental Material.
- Kids exposed in the womb to plasticizers more likely to have asthma, Environmental Health News, Sept. 17, 2014.
- Some household plastics could increase risk of childhood asthma, study finds, The Guradian sustainable-business, 17 September 2014.