Photo credit: Henry Burrows

The common use of flame retardants to treat common household items including furniture, mattresses and plastics has resulted in their accumulation in bodies of water and even further into aquatic wildlife. However, the pathway by which these chemicals make their way out of household items and into the environment has not been well understood. A recent study published in Environmental Science & Technology begins to answer this question. Researchers from the Washington Toxics Coalition and the College of William and Mary collected samples of dust and laundry waste water from 20 homes near the Columbia River in Washington State. All participants in the study were asked to wash a load of laundry containing clothes items that were not expected to have been treated with flame retardants using the same washing protocol after which the waste water was sampled. Water was also sampled from three waste water treatment plants. A total of 21 flame retardants were detected in dust sampled from the households, and 18 of those 21 flame retardants were also sampled in the waste water from washed items that were not expected to have been treated with flame retardants. Comparisons of water samples from the water treatment plants suggests that flame retardants found in the household make their way into dust, which is then washed out in the laundry and finally enters waterways after it leaves waste water treatment plants.