(Reuters Health) - Reducing air pollution at its source can substantially improve health within a few weeks, and the savings from reduced death and disease exceed the costs, according to a review of existing research.

FILE PHOTO: Birds fly next to electricity pylons on a smoggy afternoon in the old quarters of Delhi, India, October 30, 2019. REUTERS/Adnan Abidi

The authors looked at evidence of reduced deaths and disability from heart and respiratory disease and other illnesses at the individual and population levels within days or weeks of measures to reduce small-particle air pollution. The most dramatic health improvements occurred in regions with high air pollution that reduced their total output, but even small areas that decreased air pollution slightly saw improvements, the study authors report in the Annals of the American Thoracic Society.

“Air pollution is a major risk factor for health in all organs of your body, and everyone needs to be aware that air pollution has real consequences,” said Dr. Dean Schraufnagel of the University of Illinois at Chicago, the study’s lead author.

“At the same time, air pollution is an avoidable health risk,” he told Reuters Health by phone. “Reducing it can result in prompt and substantial health gains and improve climate change as well.”

Schraufnagel and colleagues at the Forum of International Respiratory Societies reviewed case studies where health improved after pollution was reduced, even if only for a short period of time, such as temporary restrictions around Olympic games.

They focused on several questions, including how quickly health changes, how much it improves, whether international standards must be met to see health differences and whether national and international air quality standards are good enough to reduce disease related to air pollution.

Overall, the team found that respiratory and irritation symptoms like coughing, sore throat, phlegm and shortness of breath improved within a few weeks after a reduction in pollution output from sources such as a steel mill, or pollution-reduction measures during the 1996 and 2008 Olympics. In addition, fewer children were absent from school or went to emergency rooms with severe asthma, and doctors saw fewer hospitalizations, clinic visits, premature births, heart attacks and deaths overall.

In particular, bans on smoking in public areas reduced deaths overall, especially from heart and lung diseases. Ireland’s national smoking ban in 2004, for instance, reduced heart attacks and childhood asthma attacks.

“The decrease in death and major diseases surprised me, but once you think about it, it makes sense because someone with heart disease could come in contact with smoke or fine particles in the air and have more stress on their body,” Schraufnagel said. “Policymakers and the public need to know how important this is.”

Reducing household air pollution is important as well, he added. Switching to cleaner fuel, upgrading stoves and using household air filters significantly reduce health issues, the study authors found, including headaches, high blood pressure and asthma. Specifically, electric high-efficiency particulate air (HEPA) purifiers decreased exposure to allergens and particles inside homes.

On the largest scale, the authors cite the U.S. Clean Air Act as one of the most successful public health laws of all time, noting that it returned monetary benefits 32-fold greater than the costs of cutting pollution, according to a calculation by the U.S. Environmental Protection Agency. The savings came from reduced premature deaths, including 200,000 fewer heart attacks per year, and 66,000 fewer hospital admissions for respiratory disease per year.

Although air pollution affects everyone, the study authors point out, the most vulnerable groups face higher risks, including children, the elderly, people with chronic diseases and the poor. Urban growth, industrialization and global warming contribute to these factors, which raises the degree of urgency for pollution control.

“To reduce air pollution and limit climate change, we need a rapid transition to a cleaner and renewable energy system coupled with increases in energy efficiency,” said William Fisk of Lawrence Berkeley National Laboratory’s Indoor Environment Group in Berkeley, California, who wasn’t involved in the review.

“Get informed. With knowledge, individuals can reduce their air pollution exposures, particularly their indoor exposures, which often dominate,” he told Reuters Health by email. “The collective action of individuals is essential to reduce future air pollution and climate change.”

SOURCE: bit.ly/2Ew54qG Annals of the American Thoracic Society, online December 1, 2019.