Coal Is the Most Dangerous Pollutant for Heart Disease, Study Says

All it takes is a rudimentary understanding of human physiology to understand that breathing polluted air isn’t a good thing for our bodies. But not all pollution is created equal, and new research shows particles released by burning coal for electricity are some of the most damaging to a person’s health.

The study, published in the journal Environmental Health Perspectives, evaluated nearly 450,000 participants in 100 U.S. cities to research the effects of different types of pollution particles on heart disease. Fossil fuel particles, especially coal, were found to be more closely linked to death than other pollution. The research suggests that a particle of coal pollutant contributes five times as much as the average pollutant particle to the chances of death from heart disease.

Read More: China’s Carbon Dioxide Emissions Far Greater Than Previously Acknowledged

The new research comes as delegates from around the world are meeting in Paris for a landmark conference aimed at curbing climate change. Coal, the most carbon rich fuel source, has played an essential role in driving economic growth in the industrialized age. The United States has derived 18% of the country’s energy consumption from coal power plants in recent years and many developing countries rely on the energy source almost exclusively to fuel their economies.

But the tide is changing on coal as policymakers have increasingly realized how the energy source contributes to climate change and the effect its pollution has on human health. Both the U.S. and China, for instance, have announced plans to stem coal production. Air pollution—largely from coal-fired power plants—in China causes 1.6 million premature deaths annually, according to recent research.