GREENSBORO, N.C. — When you're thirsty a lot of us just head for the tap water. 

But a new study shows that may be a lot more dangerous than you think. 

The study was released by the Environmental Working Group just this Thursday. 

They found that 87% of the more than 100% cancer cases linked to drinking tap water was due to byproducts of chemicals in the water.

Those chemicals were actually used to disinfect the water and arsenic which naturally occurs during the process. 

Your best bet to avoid it? 

According to the group, it's Water filters. It could be advanced ones that cost several thousand dollars or simple Brita pour-through filters. Look to pay about 16 dollars or more if you go that route.  

The Environmental Work Group also offers free reports on the contaminants in your neighborhood. You can check it out by clicking here.

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