BPA is a hormone-disrupting chemical found in some plastics. Chronic exposure may increase the risk for breast cancer, infertility, thyroid disease, PCOS, insulin resistance, and heart disease. Several countries around the world have banned BPA, and many Australians have taken steps to reduce their exposure.

Most BPA exposure comes from food that has been stored in plastic-lined tins (tinned tomatoes are the worst), but EFTPOS receipts or thermal paper receipts are a source of substantial exposure. 

Thermal receipts are up to 3 percent BPA by weight. Holding them with a dry hand transfers BPA onto the skin. Wet or greasy hands pick up 10 times more. After two hours, the BPA is completely absorbed into the blood stream, and cannot be washed off. Alcohol (from hand wipes, for example) increases the rate of absorption.

This kind of BPA exposure may be more harmful than what we receive from food. Says Sonya Lunder, a senior analyst for the Environmental Working Group:

"This is a very different kind of toxicological exposure. BPA is going right into the bloodstream in a free, unmetabolized and more active state, which is different than consuming it through diet."

The best advice is to handle receipts as little as possible. Handle them with dry hands, and wash hands with soap and water.