Dhaka, Nov. 7 -- Women with higher levels of two common "forever chemicals" in their blood face a significantly greater risk of developing an aggressive form of breast cancer, a new US federal study has warned.

Researchers found that women with the highest levels of perfluorooctanoic acid (PFOA) in their blood had a 67 percent higher risk of oestrogen receptor-negative (ER-negative) breast cancer, The Independent reports.

Those with the highest levels of perfluorooctanesulfonic acid (PFOS) faced a 93 percent higher risk, according to the British newspaper.

ER-negative cancers do not respond to hormone therapy, grow faster than other types, and account for roughly 15 per cent of all breast cancers.

The study drew on data from the Natio...