It is a simple equation: importing goods results in exports of emissions and vice versa. Photo: © Hung Chung Chih –

Air pollution health impacts shifted by global trade

International trade has moved more than 750,000 air pollution-related deaths from regions that import goods to those that produce them.

An international study led by atmospheric chemist Qiang Zhang of Tsinghua University in Beijing has investigated the effects of international trade on air pollutant emissions, air quality and resulting health damage by combining four global models to estimate premature mortality caused by fine particulate matter (PM2.5) pollution as a result of atmospheric transport and the production and consumption of goods and services in different world regions.

PM2.5 in ambient air originates both from primary particles emitted directly into the air and from secondary particles produced as a result of chemical reactions of PM2.5 precursor pollutants, namely sulphur dioxide, nitrogen oxides, ammonia and volatile organic compounds. PM2.5 can cause or aggravate cardiovascular and lung diseases, heart attacks and arrhythmias. It can also cause cancer.

It was found that of the 3.5 million premature deaths related to PM2.5 pollution in 2007 worldwide, about 12 per cent (411,000 deaths) were related to air pollutants emitted in a region of the world other than that in which the death occurred, i.e. resulted from cross-border transport of air pollution.

For example, air pollution produced in China in 2007 was linked to more than 64,800 premature deaths in regions other than China, including more than 3,100 premature deaths in western Europe and the USA.

But 22 per cent – or 762,000 – of the total number of premature deaths were associated with goods and services produced in one region for consumption in another, meaning that international trade in effect shifts the health damage of production from countries that import goods to those that produce them.

According to the study, consumption in western Europe and the United States was linked to more than 108,600 premature deaths in China. The results show that the transboundary health impacts of PM2.5 pollution associated with international trade are greater than those associated with long-distance atmospheric pollutant transport.

One of the conclusions of the study is that if the cost of imported products is lower because of less stringent air pollution controls in the regions where they are produced, then the consumer savings may come at the expense of lives lost elsewhere.

The authors also conclude that improving pollution control technologies in China, India and elsewhere in Asia would have disproportionately large health benefits in those regions and worldwide, and that international cooperation to support such pollution abatement efforts and to reduce “leakage” of emissions via international trade is in the global interest.

Christer Ågren

Source: Science, 29 March 2017.
The study: “Transboundary health impacts of transported global air pollution and international trade.” By Qiang Zhang et. al., Nature, Vol 543, 30 March 2017.



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