Asthma is the most common chronic disease of children in Canada, affecting 12.5 per cent of children. In the past decade, studies have linked asthma and exposure to phthalates, a group of chemicals that appear in countless consumer products, including flooring and PVC materials to air fresheners and fragrance.

Statistics Canada has found that the prevalence of childhood asthma is rising especially among boys (between 1994 and 2001, the rate had increased from 11 per cent to 13 per cent, which is statistically significant). With childhood asthma on the rise, it is becoming more urgent to research and understand how chemical exposures may increase risk.

Previous studies have looked at children’s respiratory health and phthalates that are commonly found in PVC and flooring materials (the phthalates most commonly used in fragrance have a different molecular structure), and potential allergy risk from exposure to phthalates in house dust. This led scientists to wonder if there might be a relationship between asthma and pre-natal exposure to the chemicals. The developing fetus is extremely sensitive to chemical exposures, and phthalates that pollute the home can be readily ingested by pregnant women.

Phthalates enter the air readily and linger in house dust, and as a result their presence is so widespread, scientists who want to study human exposure face a challenge looking for an unexposed control group with which to compare an exposed population.  For this reason, children’s health researchers at the Columbia University’s Mailman School of Public Health tested levels of exposure, comparing 300 pregnant inner-city women with the lowest levels of phthalate metabolites in their urine, to those with the highest levels.. In the post natal period, their children were examined by a physician following reports of respiratory symptoms, to determine if the children had developed asthma.

The study found that children born to women with high levels of the phthalates BBP and DBP in the urine while pregnant had a 72 per cent and 78 per cent increase (respectively) risk of asthma.

This is the first study of its kind. More research is needed to investigate the respiratory risks posed by prenatal phthalate exposure, but phthalates have been linked to other health problems as well, including reproductive problems, obesity, and in the case of diethylhexyl phthalate (DEHP), cancer.

You can reduce your exposure to phthalates by removing house dust by mopping, or using a damp cloth, and airing out rooms to reduce indoor air pollution. Choose new flooring products carefully, and buy shower curtains that do not contain PVC. Check out our resources to find out more about phthalates and other toxic chemicals, and how to reduce your exposure.