Almost all over the planet, rainwater contains dangerous amounts of ‘permanent chemicals’, suggests new research. These are per- and polyfluoroalkyl substances – a large group of chemicals that are created by man and do not occur in the natural environment. They also do not break down in the environment, so they are known as “forever chemicals”.

Substances have non-stick and stain-repellent properties, so they can be found in many household items – dishes, electronics, cosmetics, food packaging. However, researchers at Stockholm University have now found them in rainwater in most places on the planet including in Antarctica.

Over the past decades, the toxicity of these substances has been better studied, so their minimum permissible doses for use have decreased many times. For one of them, perfluorooctanoic acid, the permissible value fell by 37.5 million times in the USA. Among the health risks that these substances carry are infertility, delayed development in children and a higher chance of cancer.

“Although in the industrial world we don’t often drink rainwater, many people around the world expect it to be safe to drink, and it supplies many of our drinking water sources,” scientists say.