A 'Good News' Air Pollution Study for a Change

Too often we report on new studies showing how air pollution worsens public health, often causing premature death. For a change, here's a study showing how efforts to improve air quality in Southern California have boosted public health in children.

2 minute read

March 9, 2015, 7:00 AM PDT

By Irvin Dawid


Key finding: Regulatory efforts to improve air quality, especially by reducing fine particulate matter and nitrogen dioxide, pay off in the form of children being able to breath better, according to one of the nation's most comprehensive studies on pollution levels and children's public health.


PollutionLungHealth2 
Credit: USC News

"In findings from a 20-year study published (March 5) in the New England Journal of Medicine, W. James Gauderman of USC’s Keck School of Medicine and several colleagues show that cleaner air in Southern California has led to 'significant improvements' in lung function and lung growth among children here," writes Erica E. Phillips of The Wall Street Journal on "one of the largest and most detailed studies of the long-term effects of air pollution on the respiratory health of children", according to the Children's Health Study website.

“The results of our investigation make it clear that broad-based efforts to improve general air quality are associated with substantial and measurable public health benefits,” the paper says.

"The paper focuses on children in five California communities with heavy air pollution—Long Beach, Mira Loma, Riverside, San Dimas and Upland," writes Phillips. Air pollution was measured since 1994, showing steady reductions since 1994. "As those levels declined, lung-function development among the child subjects of the study—measured as the amount of air one can exhale after taking a deep breath—improved substantially."

That is important, Mr. Gauderman said, because “reduced lung function in adulthood has been strongly associated with increased risks of respiratory disease, cardiovascular disease and premature death.”

The pollution reductions were largely due to regulations on the federal level by the Environmental Protection Agency (EPA), state level by the California Air Resources Board (CARB) and on the regional level by the South Coast Air Quality Management District. "(R)ather than test whether pollution has adverse effects on health, which many studies have already shown, Mr. Gauderman’s team was able to investigate whether improvements in air quality led to better lung health."

Said Mr. Gauderman: “It’s strange to be reporting positive numbers instead of negative numbers after 20 years.”

Correspondent's note: The three-part study covered the years 1994-98, 1997-2001 and 2007-11. As of this posting, the Air Resources Board had only reported on the interim group, which was also published in the New England Journal of Medicine, September 9, 2004.

Wednesday, March 4, 2015 in The Wall Street Journal

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