Rice farming is a major source of methane emissions

IRD / Maeght

Reducing methane emissions by 20 per cent could prevent 370,000 deaths worldwide between 2010 and 2030, say researchers in Proceedings of the National Academy of Sciences this week (6 March).

The researchers add that the money saved by preventing these deaths would exceed the cost of cutting emissions.

Jason West, of Princeton University, United States, and colleagues note that a lack of data from developing countries makes it difficult to predict just how health benefits would manifest there.

The main human activities that contribute to methane emissions are cattle and rice farming. Other sources include coal mining, landfill sites, and the burning of biomass.

In the atmosphere, methane contributes to the warming of the planet through the greenhouse effect.

But closer to the Earth's surface, it also reacts to produce ozone, which has been linked to premature deaths in Europe and North America, through cardio-respiratory disease, among others.

Extrapolating this data to developing countries where infectious diseases cause a greater proportion of deaths is difficult, but West insists on the need to monitor and reduce the gases globally.

West told SciDev.Net that developing countries benefit from actions other nations take to reduce methane emissions.

Under the UN Kyoto Protocol, several projects are capturing methane before it is emitted and converting it to energy in order to reduce the greenhouse effect.

West's research suggests such efforts will have indirect benefits for human health by reducing the concentration of ozone at ground level.

Link to full paper in Proceedings of the National Academy of Sciences

Reference: PNAS 103, 3988 (2006)