If Sheryl Crow says so, it must be right... mustn't it?

A Facebook link by one of my friends drew my attention last week. Although it is old news, it referred to a claim by the singer Sheryl Crow that she contracted breast cancer from dioxins that were released from plastic water bottles. Dioxins in plastic? That's a new one to me.

It seems that there is a recurring rumour looping around the Internet that you shouldn’t drink water from a plastic bottle that has been left in a warm car. Crow is quoted as saying that her oncologist told her that heat will produce dioxin [sic] from the plastic. Unfortunately, if a celebrity makes a statement, there are many who will take it as fact, propagating yet another urban myth.

It's true that some dioxins are suspected carcinogens and one known as TCDD has been confirmed as a human carcinogen. But dioxins are not produced from plastic even when it is heated or left in a hot car. If you don't believe me, check out Cancer Research UK.

It may be that the oncologist in question meant to say something else other than dioxins, or was misquoted. There are other compounds that leach out of plastic water bottles, like phthalates. These are endocrine disruptors and have been linked to an increase risk of breast cancer. But phthalates are not dioxins and don’t behave like them.

There are far too many scare stories around concerning "chemicals." There are those who believe that "chemicals" are bad for us, not realising that everything around us, including ourselves, are made from chemicals. So, as scientists we should refute the false claims at every opportunity. As for Sheryl, "All I Wanna Do" is get the facts right.