A link between air pollution and infant health has long been suspected although the exact biological mechanisms through which it occurs are not well understood.
Carbon monoxide is an odorless,colorless gas that primarily comes from transportation sources,with as much as 90% of CO in cities coming from motor vehicle exhaust (Environmental Protection Agency, January 1993, 2003).
CO bonds with hemoglobin more easily than oxygen, reducing the body’s ability to deliver oxygen to organs and tissues. While CO is poisonous to healthy adults at high levels, infants are particularly susceptible because they are smaller and often have existing respiratory problems.
In pregnant women, exposure to CO reduces the availability of oxygen to be transported to the fetus.
Moreover,carbon monoxide readily crosses the placenta and binds to fetal haemoglobin more readily than to maternal haemoglobin and is cleared from fetal blood more slowly than from maternal blood,leading to concentrations that may be 10–15% higher in the fetus’s blood than in the mother’s.
Indeed, much of the negative effect of smoking on infant health is believed to be due to the CO contained in cigarette smoke (World Health Organisation, 2000).
A link between air pollution and infant health has long been suspected although the exact biological mechanisms through which it occurs are not well understood.
Carbon monoxide is an odorless,colorless gas that primarily comes from transportation sources,with as much as 90% of CO in cities coming from motor vehicle exhaust (Environmental Protection Agency, January 1993, 2003).
CO bonds with hemoglobin more easily than oxygen, reducing the body’s ability to deliver oxygen to organs and tissues. While CO is poisonous to healthy adults at high levels, infants are particularly susceptible because they are smaller and often have existing respiratory problems.
In pregnant women, exposure to CO reduces the availability of oxygen to be transported to the fetus.
Moreover,carbon monoxide readily crosses the placenta and binds to fetal haemoglobin more readily than to maternal haemoglobin and is cleared from fetal blood more slowly than from maternal blood,leading to concentrations that may be 10–15% higher in the fetus’s blood than in the mother’s.
Indeed, much of the negative effect of smoking on infant health is believed to be due to the CO contained in cigarette smoke (World Health Organisation, 2000).
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