ISLAMABAD                 -               Scientists have found an association between an increase in ozone exposure and short-term risk of death.

New research suggests that authorities globally should lower their recommendations for ozone thresholds.

An international team of scientists has found an association between increased exposure to ozone and the short-term risk of death.

The findings, which appear in the BMJ, suggest that stricter air pollution policies would significantly reduce these deaths.

Ozone pollution

Ozone is a type of gas that consists of three oxygen atoms.

According to the United States Environmental Protection Agency (EPA), ozone has different health effects depending on where it comes from. Stratospheric ozone helps shield life on Earth from the sun’s ultraviolet radiation and, as such, is a benefit to human health.

However, ground-level ozone (GLO) has associations with a variety of health issues. It is especially dangerous for older people, children, and people with diseases of the lungs, such as asthma.

According to the EPA, GLO forms when pollution reacts with sunlight. This pollution is produced through combustion, overwhelmingly from human-created sources that burn fossil fuels, such as vehicles and power plants.

Quantifying the effects

The authors of the study note that while many studies document the adverse health effects of ozone exposure, they do not often address the increase of short-term deaths it causes. Instead, studies have typically focused on longer-term general adverse health issues.

Quantifying the short-term effects of ozone exposure can be helpful when it comes to forming a policy on air pollution.

According to the article in the BMJ, the World Health Organization (WHO) suggest an ozone threshold of 100 micrograms per cubic meter of ambient air (100 µg/m3), the European Union (EU) put that figure at 120 µg/m3, the United States suggest 140 µg/m3, and finally China recommends 160 µg/m3.

Lower pollution thresholds

Drawing on data from the WHO, the team notes that over 80 per cent of people who live in an urban area where authorities record air pollution levels are exposed to higher air pollution levels than the WHO’s recommended threshold of 100 µg/m3.

The team behind the study did note some limitations: the study is observational, which means that it cannot demonstrate why heightened ozone levels increase the number of short-term deaths.