Study Links Chemicals to Breast Cancer.

A new study by Canadian researchers released last month shows correlation between the exposure to certain chemicals and pollutants before a woman reaches her mid-30s and the possibility of a higher risk of developing breast cancer after the menopause.

The researchers found that women exposed to the synthetic fibers acrylic and nylon fibers, and to petrol products polycyclic aromatic hydrocarbons during the course of their work appeared to be most at risk.

They cite that occupational exposure to these compounds may increase the risk of developing postmenopausal breast cancer.  However, some experts commenting on the study expressed caution, saying such links can crop up by chance. 

The overall power of such a study isn't quite strong, however, rest assured it will draw attention like a trailer park attracts tornadoes.

The Canadian scientists conceded their findings could be due to chance, but also said they were consistent with the theory that breast tissue is more sensitive to harmful chemicals if the exposure occurs when breast cells are still active -- in other words, before a woman reaches her 40s.

The researchers based their findings on more than 1,100 women, 556 of whom were diagnosed with breast cancer in 1996 and 1997 when they were aged between 50 and 75 and had gone through the menopause.

A team of chemists and industrial hygienists investigated the women's levels of exposure to around 300 different substances during their employment history.

After taking account of the usual factors associated with an increased risk of breast cancer, the analysis indicated a link between occupational exposure to several of these substances, the group found.

Compared with the comparison group, the risk peaked for exposures before the age of 36, and increased with each additional decade of exposure before this age, they found.

This meant women who were exposed to acrylic fibers appeared to run a seven-fold risk of breast cancer, while those exposed to nylon fibers almost doubled their risk.

The scientists said more detailed studies focusing on certain chemicals were now needed to try to establish what role chemical exposure plays in the development of breast cancer.