Exposure to high levels of tungsten, a rare metal found in mobile phones, doubles the risk of strokes, particularly for those under the age of 50, according to a University of Exeter study.

Although the rate of exposure to tungsten is currently low, in recent years, there has been an increase in the demand and supply of the material. The metal is now frequently used in the production of everyday items such as mobile phones, computers, light bulbs, and a number of industrial and military products.

During the manufacturing process, small amounts of the metal escapes into the environment and eventually gets into rivers and farmlands. Too much exposure to the metal can adversely affect future generations.

'Whilst currently very low, human exposure to tungsten is set to increase,' said lead researcher Dr Jessica Tyrrell, from the University of Exeter, in a statement. 'We're not yet sure why some members of the population have higher levels of the metal in their make-up, and an important step in understanding and preventing the risks it may pose to health will be to get to the bottom of how it's ending up in our bodies.'

For the study, experts analyzed data from the US based National Health and Nutrition Examination Survey (NHANES) of 8614 participants aged between 18 and 74 over a 12 year period. They found that people with high levels of tungsten in their system were found to be twice as likely to suffer a stroke.

"The relationship we're seeing between tungsten and stroke may only be the tip of the iceberg. As numerous new substances make their way into the environment, we're accumulating a complex chemical cocktail' in our bodies," Co-author Dr Nicholas Osborne said in the statement.

"Currently we have incredibly limited information on the health effects of individual chemicals and no research has explored how these compounds might interact together to impact human health."

The study has been published in the journal Public Library of Science ONE.

According to Stanford University, stroke is the second leading cause of death in the West, after heart diseases. Every year, more than 795,000 people in the United States have a stroke. It kills almost 130,000 (1 in every 19 deaths) Americans each year, CDC reports.

Stroke causes disability in adults - loss of motor control, urinary incontinence, depression and memory loss. More than half of all survivors depend on caretakers.

Dr Madina Kara, Neuroscientist at the Stroke Association, told Daily Mail UK that this is the first study that has established a link between tungsten and an increase in the occurrence of stroke. Previously, it was found that environmental factors like air pollution are a significant risk factor for stroke.

"Whilst this research reveals increased tungsten levels in those having stroke, follow-on studies are required to assess the direct effects of tungsten on our health and its link to stroke. Lifestyle factors such as smoking, lack of exercise and poor diet increase your risk of stroke. High blood pressure remains the single biggest risk factor for stroke. We know that half of all strokes could be prevented if people took steps to monitor and control their blood pressure," Kara said.