Louisiana and Texas are the states that emit the most chemicals dangerous to children, according to a report released yesterday by activist groups. It found that about half of all toxic chemical emissions reported to the federal government are suspected to affect the way children’s bodies and brains develop, and drew attention to a finding earlier this summer by the National Academy of Sciences that estimated that at least 360,000 children in the U.S. have developmental or neurological disabilities caused by toxic chemicals. The report by the National Environmental Trust, Physicians for Social Responsibility, and the Learning Disabilities Association was based on 1998 data from the U.S. EPA’s Toxics Release Inventory, the most recent year for which such information was available.