The Government of Canada has just announced new legislation that will significantly restrict the levels of six phthalates in children’s toys and child care products. Europe imposed similar restrictions several years ago, and the US in 2009. Today I’ll briefly look at why these restrictions are in place, why they only apply to toys and child care products, and what it all means.
What are phthalates?
Phthalates, also known as phthalate esters, are a group of organic chemicals that are commonly used to soften plastic. They’re used in a wide range of soft plastic, rubber and vinyl products, such as flooring, shower curtains, packaging and toys, as well as in paints, waxes, adhesives, and more. The regulations apply specifically to 6 phthalate compounds: di 2-ethylhexl phthalate (DEHP), dibutyl phthalate (DBP), benzyl butyl phthalate (BBP),diisononyl phthalate (DINP), diisodecyl phthalate (DIDP) and di-n-octyl phthalate (DNOP); there are other phthalate compounds not covered by the regulations (based on lower toxicity or due to their not being used in these products).
Why are they being regulated?
Health Canada and Environment Canada performed risk assessments on these substances several years ago. These risk assessments involved estimating how much of these substances a person could be exposed to, and comparing that to the dose that could potentially lead to adverse health effects.
In the case of DEHP, for example, Health Canada estimated that an infant might be exposed to just under 0.008 milligrams per kilogram body weight per day (mg/kg/d) from food, anywhere up to 0.0115 mg/kg/d from toys and child care products, and much smaller amounts from other exposure media such as air, water and soil. They also estimated exposures for other age groups. For health effects, they determined that the effects that occur at the lowest doses are reproductive and developmental effects. From a variety of animal studies, they found that the lowest dose where there was any observable effect was 91 mg/kg/d, and a dose of 44 mg/kg/d didn’t have any observable effects. They used the 44 mg/kg/d as a starting point, then divided by 10 to account for extrapolating from animals to humans, another 10 to account for sensitive humans, and a further 10 due to potential effects on foetuses, resulting in a dose of 0.044 mg/kg/d that Health Canada was fairly confident was safe. The total predicted exposure was less than this amount, but not by a whole lot, and there was some concern that some of the exposures could have been underestimated, so Health Canada concluded that DEHP has the potential to cause harm to humans, leading to a requirement for risk management to protect the population.
Why only regulate in toys and child care products?
When the Government of Canada (or other government) decides to regulate a toxic substance, they look at both mitigating the potential risks of the substance and the socioeconomic effects of any action they take. While banning phthalates in all uses might seem like a good idea, they do have a lot of important uses. So instead the government focuses on uses leading to the largest human exposures and uses where there are good alternatives.
In the case of phthalates, where developmental effects are the biggest concern, children are the most susceptible. As seen in my example above, exposure from toys and child care products was also potentially the greatest source of exposure for children. Therefore, eliminating or at least reducing the exposures from toys and child care products would significantly reduce exposure, particularly to the most sensitive group.
The other main source of exposure is food. However, the source in food isn’t always fully known (and in fact one study found that people who eat a “natural” and healthy diet may have the highest exposures to at least some phthalates). Since it’s not always know where in the food production chain the phthalates are entering food, and much of our food comes from other countries, it’s a lot harder to control this exposure.
What does it all mean?
Overall the new regulations probably won’t have a huge effect, since Europe and the US already have similar regulations in place. However, it does prevent manufacturers of toys and child care products from sending (potentially cheaper) products with phthalates to the Canadian market, and gives Canadian parents an added level of comfort – at least assuming the manufacturers comply with the regulations.