Warmer climate could mean selenium scarcity

Consuming cereal grains grown in selenium-poor soil can lead to a dietary deficiency of this trace mineral. Keystone

An international research team has shown that climate change could lead to diminished soil concentrations of selenium – a trace mineral that is essential to human health.

The amount of selenium in our food – such as cereal grains – is closely linked to soil concentrations of this trace element. But according to a study led by the Swiss Federal Institute of Aquatic Science and TechnologyExternal link (EAWAG), these concentrations are likely to dwindle significantly by the end of the century as a result of climate change.

The research team, which also included scientists from the Swiss federal technology institute ETH Zurich as well as Germany and the United Kingdom, used multiple sets of data collected for other purposes to model average global soil selenium concentrations between 1980-1999 and between 2080-2099.

They found that overall, about two-thirds of soil could be expected to lose 9% of its selenium under “moderate” climate change conditions, with agricultural regions in Europe, India, China, South America, southern Africa, and the south-western United States most affected. Their research was published this week in a special review in the journal PNASExternal link.

Selenium is an essential trace element for human health, and selenium deficiency can lead to myocardial problems, or those affecting the heart’s muscle tissue. The researchers estimate that already, some one billion people worldwide suffer from problems related to selenium deficiency in their diet.

The researchers, who describe the study as an early warning to humanitarian organisations and the agricultural industry, suggest counteracting a future lack of selenium in the soil with selenium-containing fertilisers, as Finland has done since 1984. Other possible solutions include using selenium as an additive in animal feed.