Some scientists study how exposure to toxic chemicals alter children’s behaviors. And we usually examine the behaviors of typical children.
In one study, we found that the average number of ADHD-behaviors in children increased as the amount of lead in their blood increased. The percent of children with ADHD more than doubled, from 5 to 13%.”
In contrast, in a study on autism, the number of autism-related behaviors didn’t increase in the typical child as the amount of lead in their blood increased. But children who already had more autistic behaviors became more autistic as the amount of lead in their blood increased. Children with fewer autistic behaviors weren’t affected.
Most toxic chemicals, like lead, damage the brain in many ways. There is no way to know which children will be affected. In order to protect the few, we have to protect everyone.