Phthalates as a public health concern.
An NPR reporter ignores results from decades of research conducted around the globe.
A National Public Radio (NPR) report by science correspondent Jon Hamilton (online April 5) rightly points to significant public concern regarding potential adverse effects of phthalates but comes to the wrong conclusion about the scientific evidence.
Phthalates are industrial chemicals used in a variety of plastic products (toys, medical devices) to provide flexibility and pliability. In the US, several manufacturers have started to reduce or remove phthalates from their products but the debate for a federal ban in consumer products is ongoing.
Mr. Hamilton's conclusion that a federal ban of the chemicals in children toys is not based on science ignores years of research done in laboratories across the globe. This point hits home because he fails to interview independent scientists for this article. Instead, he relied on statements provided by a representative of one federal agency and testimony in Congress to explain the science.
Animal studies find that the chemicals cause hormonal changes in both males and females with a variety of reproductive effects. A growing body of human studies has shown that phthalates are associated with lower sperm quality in men, sperm DNA damage and shortened anogenital distance in boys exposed while in the womb.
Meanwhile, the experiments supported by the Consumer Product Safety Commission (CPSC) were limited in scope and did not reflect real-life exposure patterns--that children are generally exposed by mouthing of toys and are particularly vulnerable to potential adverse effects. In the first study, adults, rather than children, were asked to chew phthalate-containing material and chemical release was measured in saliva. In another study, toys provided to children did not include pacifiers and teethers, which are most subjected to mouthing by children.
Phthalates are short lived in the body and are not known to accumulate in the environment. Nevertheless, they are widespread in people at levels that vary according to frequency and length of exposure. For example, phthalate metabolites – which are used to measure exposure – are present in 90 - 100 percent of urine samples from women and men in the US.
Because phthalates are present in human urine, it is reasonable to conclude that the potential for reproductive effects exists. Therefore, the possibility of adverse effects in humans cannot be excluded at this time, until the results of human research show otherwise.
Although there is a need for more research, the push for a federal ban on phthalates in children toys is indeed based on available scientific data. The public will be well served if the press will provide information from independent scientists on issues of concern regarding exposure to endocrine active compounds present in our environment.
