Solvent ‘may raise cancer risk for women’

A SOLVENT found in paints, dyes and fuel additives may raise the risk of breast or ovarian cancer among women on hormone replacement therapy or taking the contraceptive pill, it was claimed yesterday.

New research showed that the chemical, ethylene glycol methyl ether (EGME), boosted the activity of hormones used in the treatments by up to 10 times.

This would increase the danger for women threatened by hormone-sensitive breast and ovarian cancers, triggered by the action of oestrogen or progesterone.

The hormone-disrupting effect of the solvent may also be responsible for miscarriages and infertility, said the US scientists at Duke University Medical Centre in Durham, New Carolina.

Vaproic acid, a drug widely prescribed for epilepsy, with a similar chemical structure to EGME, had the same effect.

"These data should prompt caution for patients who are exposed to either of these chemical compounds while taking any oestrogen or progesterone-containing medications, such as hormone therapy, oral contraceptives or tamoxifen for breast cancer," chief researcher Dr Donald McDonnell said.

Exposure to the class of compounds which includes EGME was already linked to reproductive failures in humans and rodents. In men, they cause reduced sperm counts and in women spontaneous abortions and irregular ovulation.

However, the mechanism behind these effects has been unclear until now. The team analysed the behaviour of the compounds inside cells to investigate how they influenced hormonal activity. They found both EGME and valproic acid accelerated a process called gene transcription the mechanism by which the genetic code is read, copied, and prepared for action within the cell. Transcription is required for cells to thrive and carry out their work in organs and tissues. But uncontrolled or inhibited transcription can lead to numerous diseases and disorders, including cancer.

The findings were published in the journal Proceedings of the National Academy of Sciences.

Dr McDonnell said they highlighted the importance of screening chemicals for their effect on hormones.

"Clearly, these chemicals are affecting the cellular environment where oestrogen works, and our goal would be to identify other chemicals with the same effect and alert the public to the potential for such drug-drug interactions," he said.