39 brands of straws have been tested.
So-called 'eco-friendly' paper straws could be as bad for the environment as plastic ones.
Belgian researchers tested 39 brands of straws and found some contain long-lasting and potentially toxic chemicals.
They were detected in the majority of the straws but were most common in those made from paper and bamboo.
The substances break down very slowly and can persist over thousands of years leading to them being called 'forever chemicals.'