Not only smoking but also exposure to it attacks the people’s health. In a new study, researchers have determined that prenatal exposure to cigarette smoking, when combined with a specific genetic variant, places children at increased risk for aggressive behavior and other behavioral problems.

Scientists identified a long-lasting influence on a child's behavior precipitated by the monoamine oxidase A (MAOA) gene variant in conjunction with prenatal exposure to tobacco. MAOA is an enzyme which regulates key neurotransmitters in the brain.

The genetic variant responsible for increased risk of behavioral problems differs between boys and girls, researchers found. In boys exposed to tobacco smoke prenatally, the low-activity MAOA (MAOA-L) gene variant was associated with increased disruptive social interactions, aggressive behavior, and serious rule-violating.

Among girls, the high-activity MAOA (MAOA-H) gene variant was associated with increased disruptive behavior. In addition, girls with both the MAOA-H variant and prenatal exposure to cigarette smoke had a tendency to perceive anger in a range of facial expressions, but that was not seen among boys.

Researchers investigated also mothers who smoked during pregnancy, and they found that the risk of disruptive behavior is higher for both boys and girls.

This research as many others showed that children face a higher risk than adults of the negative effects of secondhand smoke. Not only because the child's body still developing physically, but because their breathing rate is faster than that of adults. Adults breathe in and out approximately 14 to 18 times a minute, where newborns can breathe as many as 60 times a minute. Up until a child is about 5 years old, the respiratory rate is quite fast, usually between 20 and 60 breaths per minute.

The best air for children is fresh air not cigarette smoke, remember this!