Oh, the twinge of guilt we feel if we say yes to a plastic bag at the shops. We all know the feeling. But does our concern about the amount of plastic choking landfill, not to mention seabirds, need to go further than just the environment? Could our daily plastic exposure actually be harming our health?
A major component of many plastics, Bisphenol A (BPA) is everywhere - not just in plastic containers but also lining tin cans - and it's increasingly under scrutiny because of its potential, in large quantities, to inflict harm on humans.
American Florence Williams became so concerned about the amount of toxins in her world that she embarked on a three-day BPA detox. Williams, the author or Breasts: A Natural and Unnatural History, was particularly worried about toxins accumulating in breast tissue. This concern stemmed from her curiosity about why young girls are developing breasts earlier than previous generations; she feared it could be in part due to toxins promoting hormonal changes.
Williams spent just three days living a life as devoid of BPA as possible by eating raw food untouched by plastic. She banned deodorant and shampoo and rode her bike to avoid toxins found in her car. What's more, she took her seven-year-old daughter along for the ride. Along the way, she tested her urine to find out just how much of the stuff was in her system.
Despite the short time frame of her experiment, the result was dramatic - the level of BPA in Williams's urine dropped by 85 per cent, from 5.1 nanograms per millilitre before the detox to just 0.8 afterwards. Her daughter's levels dropped by 18 per cent.
"On the one hand that was encouraging, because it's possible to alter the levels of these substances in your body," says Williams.
"But on the other hand it was discouraging, because it was so hard to do. I had to make extreme lifestyle changes. I was a vegan during that time. It's really hard to buy food that hasn't touched plastic. You don't even realise until you try it. It eliminates coffee because of how it's packaged. It eliminates cheeses and yoghurts.
"I ate a lot of salad. I cooked up some quinoa that was packaged in paper. I was able to buy some stuff at the farmers market."
While conducting her experiment, Williams was warned by scientists that many of the global standards for safe exposure to BPA are out of date.
However, not everyone is as alarmed as Williams. Dr Ian Musgrave, a molecular pharmacologist and toxicologist at the University of Adelaide, says humans would need to consume 50 cans of tinned food (which contains BPA) daily to raise alarm bells about absorption.
"It's the dose that makes the poison," says Musgrave. "Relatively high levels of BPA, such as from industrial exposure, can definitely have adverse health consequences. But all the latest research reinforces our understanding that the levels of exposure Australians have to BPA through food and other sources is well below that which would cause harm."
Musgrave suggests that people should be more concerned about the caloric intake from processed and packaged foods than the levels of BPA in them.
In 2010, the federal government announced a voluntary phasing out of plastic baby bottles containing BPA by major retailers, in line with other governments globally. However, it insists this is in response to consumer preference and demand, not product safety.
Food Standards Australia New Zealand says that while other governments, such as Canada, have phased out the use of BPA in some products, it doesn't believe this action is supported by the risk assessment.
Williams thinks regulators have been "asleep at the wheel" when it comes to testing common compounds for health effects, and says it's hard to control exposure and unrealistic to "become your own environmental protection agency".
She adds, "You can't live in a bubble and you'll make yourself crazy if you try - that's not good for your health, either. I try not to be too alarmist because we don't know for sure that harm is being done. We just know that we're not doing enough."
Florence Williams appears on The Secret Life of Breasts, airing tonight on SBS One at 8.30pm.