The researchers studied samples of polyurethane foam and polyester foam padding from 20 new and old crib mattresses. Graduate student Brandon Boor, in the Cockrell School's Department of Civil, Architectural and Environmental Engineering, conducted the study under the supervision of assistant professor Ying Xu and associate professor Atila Novoselac. Boor also worked with senior researcher Helena Järnstrí¶m from the VTT Technical Research Centre of Finland. They reported their findings in the February issue of Environmental Science & Technology.
The researchers found:
- New crib mattresses release about four times as many VOCs as old crib mattresses.
- Body heat increases emissions.
- Chemical emissions are strongest in the sleeping infant's immediate breathing zone.
The researchers concluded that, on average, mattresses emitted VOCs at a rate of 87.1 micrograms per square meter per hour, while older mattresses emitted VOCs at a rate of 22.1 micrograms per square meter per hour. Overall, Boor said crib mattresses release VOCs at rates comparable to other consumer products and indoor materials, including laminate flooring (20 to 35 micrograms per square meter per hour) and wall covering (51 micrograms per square meter per hour).
Boor became motivated to conduct the study after finding out that infants spend 50 to 60 percent of their day sleeping. Infants are considered highly susceptible to the adverse health effects of exposure to indoor air pollutants.
"I wanted to know more about the chemicals they may inhale as they sleep during their early stages of development," he said. "This research also helps to raise awareness about the various chemicals that may be found in crib mattresses, which are not typically listed by manufacturers."
The 20 mattress samples are from 10 manufacturers. The researchers chose not to disclose the names of the manufacturers studied so that their results could draw general attention to the product segment without focusing on specific brands.
At present, not much is known about the health effects that occur from the levels of VOCs found in homes, according to the U.S. Environmental Protection Agency.
Researchers advised parents to allow new mattresses to air out in a garage or protected porch for as long a period as possible before placing it in a child's crib.