In this third edition of my post series I review thirteen studies about the impact of passive smoking on children. Twelve of them show negative impacts. I begin with the only exception: In New York, more than a thousand asthmatic children between four and nine years of age have been examined together with the air pollution at home. More than eighty percent of the homes have been heated by gas stoves with an exhaust of nitrogen dioxide, increasing the asthma symptoms. Passive smoking did not show an additional effect which is not very surprising given the fact that the damage already has been done by the gas exhaust.
Asthma in children and cigarette smoking of women at home both have increased in the past decades. Of course this is not a proof that passive smoking causes asthma in children, but it is an important piece of evidence. It is not the only one. In Finland and Russia, the asthma risk in children of smoking mothers has found to be more than triple.
In Spain, Greece and Tennessee, the risk of children's bronchitis has found to be higher when mother smokes, and the risk of middle-ear infections is increased fourfold according to a Finnish study. Other studies link maternal smoking to arterial damage, lower intelligence and ADHD in children.
The risk of maternal smoking begins in pregnancy. One effect, at first sight, seems to be positive: Smoking mothers have a lower risk of hypertension. But this is due to a poor growth of the fetus suffering from tobacco poisoning. A Swedish study has shown the risk of stillbirth to be increased by 35 percent in women smoking when pregnant.
In pregnant women exposed to secondhand smoke, the risk of defect genes is fourfold (with a higher risk of disability in the offspring) compared to non-exposed women.
The dangers of secondhand smoke (2)
The dangers of secondhand smoke (1)
Passive smoking (Wikipedia)
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