An advocacy group has filed a legal notice against major retailers that include Amazon, Target and Wal-Mart, saying that the baby products sold by these retailers have high amounts of a flame retardant that has been linked to cancer.

Center for Environmental Health (CEH) said on Thursday that its independent testing has found that 16 baby and children's products had high levels of chlorinated Tris. The agency added that the chemical was banned from children's pajamas as early as 1977, but is still being used in many children's products, even those that have no fire danger.

"Infants and young children, who are at critical stages of their development, should not be sleeping on products doused with these ticking chemical time bombs. It's past time for companies to take steps towards eliminating these harmful chemicals from products for our children and families," said Michael Green, Executive Director of the Center for Environmental Health.

A recent study had found that more than a third of all sofas in the United States might have chlorinated Tris. Flame retardant chemical pentaBDE has been linked to low IQ, poor attention spans and learning problems in children.

CEH said that it found high levels of Tris in five nap mat brands that are being sold at various outlets across the country; three foam diaper changing mats that were purchased at Walmart, Target and Babies"R"Us.

"It's past time for companies to take steps towards eliminating these harmful chemicals from products for our children and families," said Michael Green, the group's executive director, reports Los Angeles Times.

Last year, the chemical was listed under Proposition 65 by California as a cancer-causing chemical. CEH said that none of the products they tested had any warning label that may have indicated the presence of Tris in the product.