The chemical, Firemaster 550, is widely used on upholstered furniture sold in California. It first went on the market in 2005, but its chemical makeup is a trade secret and researchers are still looking into its full impact on human health and sea life.
The San Francisco Estuary Institute said it found the substance in treated wastewater sludge in Palo Alto.
The study's author suggested Firemaster 550 dust could be reaching the plants after washing down household drains.
