Active urban kids exposed to more pollutants: study

Parents, take note! Children involved in daily vigorous exercise in urban areas are more exposed to black carbon - a traffic-related pollutant - which may negatively impact their health, according to a new study.
Researchers from Columbia University in the US, also found that while physically active children had reduced airway inflammation compared to less active kids, this association was offset by due to high black carbon exposure.
Black carbon, a pollutant that is also an indicator of diesel exhaust exposure, is known to have an adverse impact on health.
However, little research has examined whether children living in urban areas receive a higher dose of the pollutant when they engage in regular physical activity.

"There are numerous health benefits associated with regular physical activity, particularly for children," said lead author Stephanie Lovinsky-Desir, assistant professor at Columbia University Medical Centre (CUMC).
"We wanted to determine if regular exercise increases the risk of exposure to air pollution in city children, and if that exposure has an impact on the lungs," Lovinsky-Desir said.

The study included 129 children (age nine to 14 years), who wore wrist motion detectors to measure their physical activity over a period of six days.
Nearly 60 per cent of the children were considered active, engaging in 60 minutes or more of moderate to vigorous activity per day Those who obtained less exercise were characterised as non-active.

Personal exposure to black carbon was monitored during two 24-hour periods, at the beginning and at the end of the physical activity assessment, with a wearable vest containing a miniature black carbon-detection device.
Following each 24-hour black carbon collection period, the researchers measured each child's level of fractional exhaled nitric oxide, a marker of airway inflammation.
They also measured each child's specific sensitivity to indoor and outdoor allergens.
The study showed that the active children were exposed to 25 per cent greater concentration of black carbon compared to non-active children.
Daily physical activity was associated with reduced airway inflammation, but that effect primarily occurred among the children who were exposed to lower concentrations of black carbon.

Exercise had no effect on airway inflammation among children exposed to the highest concentrations of black carbon.
The study was published in the journal Environmental Research.