AUGUSTA – Cheryl Denis of Portland is worried about the health of her two young daughters.

She testified Thursday before the state’s Board of Environmental Protection, supporting proposed rules to ban the sale of baby bottles, sippy cups and sports bottles that contain the chemical bisphenol-A.

Environmental activists say the chemical has been linked to problems with brain and hormone development in children.

“Would any of us knowingly give our children estrogen, even in small doses, every day?” said Denis, leader of Mom to Mom of Maine, a group of 275 mothers in southern Maine.

The board is considering a proposal by the state Department of Environmental Protection to ban the manufacture, sale or distribution of certain products for children that contain bisphenol-A.

The rules were mandated by a 2008 state law that required the state to list “chemicals of concern.”

Environmentalists, Senate President Elizabeth Mitchell — the Democratic candidate for governor — and House Speaker Hannah Pingree testified for the BPA ban, while representatives of the chemical and grocery industries spoke against it.

Steve Hentges of the American Chemistry Council in Arlington, Va., said he has studied bisphenol-A for 10 years. He said the evidence that the chemical harms children is not conclusive.

The chemical helps strengthen plastics so they don’t shatter, it’s used in lids on glass jars, and it makes canned food more sanitary, said Greg Costa of the Grocery Manufacturers Association in Washington, D.C.