Polar bears on the verge of extinction?!

The conservation agency , has warned that man-made chemicals pose a serious threat to polar bears.

The WWF says three new scientific studies show that biological changes in the hormone and immune systems of are linked to the levels of toxic contaminants in their bodies. China Radio International reported Tuesday.

The 2,000 polar bears, which are already in danger from global warming, become more susceptible to infections, while their development, behaviour and reproductive capacity also deteriorated, reports Xinhua.

According to the Health Talk, "These animals are negatively affected by chemical pollution," said study contributor, Dr. Andrew Derocher.

It is estimated that 22,000 polar bears live in the Arctic region. The WWF says these animals are also threatened by the combined effects of , and loss of habitat.

The studies also found altered hormone levels, which could lead to everything from reproductive to behavioural problems.