Tree effect on Asthma

Tree effect on Asthma

Indo-Asian News Service
New York, May 01,

Growing more trees might not only make for a less polluted environment but also lower the incidence of asthma among children, according to a study.

Researchers here based their findings on a study of the city's children in the 4- to 5-year age group. The city has an average of 613 street trees per square kilometre, and nine percent of its children have asthma.

The study found that asthma rates in this age group fell by almost a quarter for every standard deviation increase in tree density, equivalent to 343 trees per square kilometre.

This pattern held true even after taking account sources of pollution, levels of affluence, and population density, all factors likely to influence the results.

The study has been published in the latest issue of the Journal of Epidemiology and Community Health.

Asthma happens to be one of the leading causes of hospitalisation among New York's children.

Trees may be helping to curb asthma rates by encouraging children to play outdoors more or by improving air quality, the study said.

New York City is planning to plant a million extra trees by 2017, which could provide the perfect opportunity to discover exactly what impact tree density has on asthma, the authors of the study added.