Shanna H. Swan, a renowned scientist specialising in reproductive medicine, has warned about the health effects of endocrine disrupting chemicals (EDCs) such as phthalates which can end up in food via pesticides or plastics. In an interview with EurActiv, she calls on regulators to better protect consumers against those "hidden chemicals".
Politicians have long been aware of the potential health effects of "gender bender" chemicals. These include reproductive health problems in males, hormone-related cancers including testicular, prostate and breast cancer, as well as obesity and diabetes.
The European Union has been at the forefront of efforts to regulate those substances, for example by banning the use of Bisphenol A in baby bottles, or trying to reduce the amount of pesticides used by farmers. Most importantly, EU lawmakers adopted in 2006 the REACH regulation, which for the first time requested chemical producers to prove that their products are safe before they can be allowed on the market.
When confronted with such evidence, chemicals industry representatives invariably point to the same argument: It is not the substance that makes the poison but the dose. The presence of phthalates in human blood therefore cannot be cause for concern as long as the dose is kept within scientifically proven safety limits.
Swan, however, thinks exactly the opposite. "There is absolutely no doubt that tiny, tiny doses of hormones can permanently alter the development of the foetus," she said. "You cannot look at the dose alone, you must look at the dose in a particular time window," she stresses, citing the developing foetus in a woman's womb during pregnancy.
"We are never exposed to one chemical," she says. "In fact a recent study found 200 chemicals on average in babies at birth."
Some toxicologists have challenged the kind of research conducted by Swan and other environmental scientists, saying the chemicals found were well below safety threshold and that additional evidence was needed to study the combined effect of some substances.
But to Dr Swan there is now sufficient scientific evidence for regulators to take action.
"Do we need more studies? Of course we do. But do we have enough information to act on these studies that we have? I say that we do."