If a girl is exposed to certain chemicals while in her mom’s womb, she might be more likely to have behavior issues by age 7. This doesn’t seem to happen the same way in boys.

Girls might be more affected by certain chemicals early in life when it comes to developing hyperactivity, compared to boys.

Kids exposed to several hormone-disrupting chemicals at once are more likely to show high levels of hyperactivity as they grow, with the risk more than doubling compared to lower exposures.

Kids whose moms were exposed to more hormone-disrupting chemicals during pregnancy tend to have slightly more behavioral difficulties, especially boys. The effect is small but shows up more clearly in boys than in girls.

When little kids are exposed to higher levels of certain chemicals found in everyday products — especially when many of them are high at once — they’re more likely to show increasing hyperactivity as they grow.

Some chemicals we're exposed to might be linked to hyperactivity in young kids — some could make it more likely, others less, and it depends on the specific chemical.