It all comes out in the wash

October 22, 2014

Flame retardant chemicals don’t stay put in products. A study published in Environmental Science & Technology reveals they are hitching a ride on our clothes and taking a detour through our laundry, on the road to our rivers.

Flame retardants (FRs) are in the bodies of humans and animals, and in our waterways. One pathway to rivers and oceans is laundry water. FRs migrate from household products and accumulate on dust and clothing. When we wash our clothes the chemicals transfer to laundry water. (FRs and other chemicals are also found in dryer lint so washing hands after touching it is a good idea.) Even after wastewater treatment, FRs enter waterways such as the Columbia River, which empties into the Pacific Ocean.

Scientists at the Washington Toxics Coalition and the Virginia Institute of Marine Science tested for 22 FRs in 20 homes near the Columbia River. They analyzed household dust, laundry wastewater, and water entering and leaving two wastewater treatment plants that handle those communities’ water. Flame retardants were found in all of the tests.

The study found numerous flame retardants such as PBDEs, HBCD, and, at the highest levels, these three forms of chlorinated tris:

• TDCPP is associated with hormonal disruption and decreased sperm quality. California’s Prop 65 lists it as a probable human carcinogen.
• Animal studies link TCEP to reproductive toxicity, neurotoxicity, and cancer.
• *Prop 65 lists TCPP as positive for genotoxicity in vitro, but not in vivo, studies. “Of the 22 targeted FRs, TCPP was present in dust at the highest level of any single chemical.”

But doesn’t the wastewater treatment process remove harmful chemicals? Not always. Chemical compounds with certain characteristics “are inefficiently removed during wastewater treatment and thus discharged into aquatic environments.” All three forms of chlorinated tris have these characteristics and were still in the water after treatment.

The authors conclude “laundry wastewater may well be a primary source of these FRs…to the aquatic environment” and “these findings should inform public policy on use of FRs in products in the home by highlighting transfer of these compounds to waterways such as the Columbia River.”

*Correction: Previously, this blog mistakenly stated TCPP was listed as a carcinogen on Prop 65.  See TCPP for Prop 65 information.