Greenpeace said on Monday that hazardous chemicals were “widely present” in a range of outdoor gear it tested, from clothing and footwear to backpacks, tents and sleeping bags.

The environmental activist group said out of 40 products tested, only four were free of per- and polyfluorinated chemicals (PFCs).

The study showed that toxic chemicals are “still widely present in products by brands such as Jack Wolfskin, the North Face, Patagonia, Mammut, Norrona and Salewa, especially in the production of footwear, trousers, sleeping bags and some jackets.”.

PFCs are used to add waterproof and dirt-repellent finishes to outdoor apparel, but are hazardous to the environment and human health, said Greenpeace.

“Once released into the environment most PFCs break down very slowly. They can remain in the environment for many years after their release and are dispersed over the entire globe,” the report said.

The pollutants have been found in secluded mountain lakes and snow, can accumulate in the livers of Arctic polar bears and be detected in human blood, the report said.

Greenpeace said studies had shown that some PFCs “can cause adverse impacts … on the reproductive system and the immune system, as well as being potentially carcinogenic in animal tests”.

The group said an independent laboratory had tested 11 jackets and eight trousers, seven pairs of shoes, eight backpacks, two tents, two sleeping bags, one climbing rope and one pair of gloves.