Published in the open-access journal PLOS ONE, the research used data from the US based National Health and Nutrition Examination Survey (NHANES), analysing information for 8614 participants aged between 18 and 74 over a 12 year period.

Higher tungsten levels were found to be strongly associated with an increase in the prevalence of stroke, independent of typical risk factors. The findings show that tungsten could be a significant risk factor for stroke in people under the age of 50.

Recent years have seen a significant increase in the demand and supply of tungsten, which is commonly used in consumer products such as mobile phones and computers, as well as a number of industrial and military products. During its production, small amounts of the metal can be deposited in the environment, eventually making their way into water systems and onto agricultural land. 
 
"Whilst currently very low, human exposure to tungsten is set to increase,” said lead author of the research, Dr Jessica Tyrrell, of the University of Exeter medical school's European Centre for Environment and Human Health.