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Published in Summer 2006
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Report profiles chemicals and children’s health
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By Joshua Ostroff
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| Toxic Chemicals and Children’s Health in North America focuses on the releases of carcinogens, developmental and reproductive toxicants, and suspected neurotoxicants that are considered most hazardous to children’s health
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Very little is known about how industrial chemicals in the air, water and on land affect kids, but we’re learning, one baby step at a time, says the author of a new report on children’s health and toxic chemicals.
“None of us is born grown-up and things that happen [during childhood] can affect our health status throughout our lives,” says Dr. Lynn Goldman, the principal author of Toxic Chemicals and Children’s Health in North America and professor at the Johns Hopkins Bloomberg School of Public Health.
Published in May by the CEC, the report calls for further information-gathering on children’s health, while using a new methodology to bolster existing knowledge of child-specific environmental hazards and help prioritize pollution reduction efforts.
Children have unique vulnerabilities to chemicals because they are still developing and generally inhale more air, eat more food and drink more water relative to their size than adults do. Younger children also crawl on the ground, put objects in their mouths and may even eat contaminated dirt, increasing their likelihood of exposure to such toxic chemicals as lead, mercury, PCBs, dioxins, furans, phthalates and manganese.
“It’s only been the last few years that children’s health risks have captured attention and even more recently that we‘ve had a critical mass of information to look at something like PRTR (pollutant release and transfer register) data in terms of what chemicals are recognized or suspected to be toxic to children,” says Dr. Goldman.
PRTRs compile information about the releases and transfers of toxic chemicals from industrial facilities. The United States implemented their PRTR, the Toxics Release Inventory, in 1987 to track over 300 industrial chemicals—a number which doubled by the mid-1990s. The Canadian government launched its similarly-styled National Pollutant Release Inventory in 1992, covering 268 substances. This June, Mexico launches it own PRTR, the Registro de Emisiones y Transferencia de Contaminantes, which will make publicly available the data for 104 chemicals released by industry.
“PRTRs were developed out of the principle of community ‘right-to-know’ and first implemented in response to the Bhopal chemical accident in India, where thousands of people died because of an accidental release of poisonous gases at a pesticide plant,” explains the CEC’s PRTR program manager Keith Chanon. “This has been very useful for emergency responders. Experts have been pointing to hurricane Katrina and all the flooding in New Orleans, where there were a lot of questions over what chemicals were in the floodwaters.”
But as helpful as PRTR databases are, they suffer from several crucial drawbacks. They often underestimate actual releases and because each country has its own approach, the lack of continent-wide consistency makes comparisons difficult for chemicals like PCBs, which are not regularly inventoried by Canada, or dioxins, which the two countries report differently.
It’s a problem the CEC has acknowledged with its Action Plan to Enhance the Comparability of Pollutant Release and Transfer Registers in North America. The goal of the plan is to increase the amount of data comparable on a continent-wide basis, in order to gain a more complete picture of the sources, quantities and handling of pollutant releases and transfers in North America.
Inside the numbers
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Toxic Chemicals and Children’s Health in North America uses Toxic Equivalency Potentials (TEPs) to describe the relative hazard of chemical releases. The TEP is calculated by comparing the human health risk posed by the release of one pound of a chemical to the risk posed by the release of an equal amount of a reference chemical. The report also presents the more standard characterization, the amount by weight of chemicals released, typically found in national
pollutant release and transfer registers.
Both methods are illustrated in the
following example: In 2002, 472,600 tonnes of carcinogens were released and transferred by industrial facilities in Canada and the United States. The carcinogens released in the largest quantities to air were styrene and acetaldehyde. When TEPs are applied, carbon tetrachloride ranked #1 and lead and its compounds #2. Styrene, because of its lower toxicity, falls all the way to #23
in the TEP rankings.
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The cornerstone of the project is the CEC’s annual Taking Stock report, which matches data from the national databases whose information is limited to that provided by companies on the volume of chemical releases and transfers—not the toxicity and potential to cause harm. This is where a new methodology like Toxic Equivalency Potentials (TEPs) comes in.
“Not all chemicals are equal. You want a system that says chemical X is ten times worse than chemical Y based on its inherent toxicity and exposure potential. That’s what TEPs do. They provide a weighting system transforming raw chemical release data into something more risk-based,” explains Bill Pease, who developed the TEP system at the University of California, Berkeley.
This can drastically alter the ranking of certain chemicals such as lead, which was 11th amongst carcinogenic air releases in 2002, with 960 metric tonnes, but its toxicity bumped it to number two.
“This approach is saying it’s smarter to integrate [TEPs] with release data because this will provide us with more socially-responsible guidance,” says Pease. “The smart thing to do is to focus our limited resources on the chemicals that deliver the biggest bang for the buck in terms of health benefits if we reduce their release.”
For example, persistent, bioaccumulative toxic chemicals like mercury concentrate in the food chain and therefore more people are potentially exposed to it at more dangerous levels. Exposure to mercury in utero can affect brain development and lower IQ levels.
“We have seen a lot of it up in the far north, particularly, among the Inuit in Canada and Alaska. It’s not
that there are industries up there but because of the global flow of pollutants up to the polar region,” says
Dr. Goldman.
“These effects on neurodevelopment tend to be subtle at the individual level but quite significant when you look across an entire population. It’s like the radiation risk you had after Chernobyl or the A-bomb testing. There is a significant increase in the numbers of people who get cancer but you’re unlikely to see that manifested in one individual child. You see it across a population. If you can prevent a loss of IQ points in the first place, that’s far more effective than taking somebody who is struggling in school and trying to help them do better.”
The report did, however, demonstrate that although 472,600 tonnes of carcinogens were released by North American facilities in 2002, nevertheless there had been a decrease of 26 percent between 1998 and 2002. Similarly, recognized developmental and reproductive toxicant releases decreased by 28 percent to 482,600 tonnes, suspected developmental and reproductive toxicants went down by seven percent, to 2.25 million tonnes, and suspected neurotoxicants fell by 11 percent, to over 2.5 million tonnes between 1998 and 2002.
“There’s good progress being made, but significant amounts of dangerous chemicals are still being released,” says Chanon.
The report’s primary recommendations are to prioritize the reduction of the most hazardous contaminants and fill in the data gaps. In particular, a clearer picture can be had if more chemicals are tracked by PRTRs and the countries harmonize their efforts to facilitate comparative analysis. The next step is further examining the impact of these chemicals on children through biomonitoring of populations living around industrial facilities to better inform the public, policy makers and the companies themselves.
In the meantime, this report provides a vital tool to make parents aware of the potential environmental dangers to their children.
“A lot of people aren‘t aware of chemical risks,” says Chanon. “They assume that a chemical plant or facility has been approved by the government and therefore should be operating at safe levels. But there are actions people can take to further their knowledge and reduce their exposure. For example, through increased awareness, parents could change the play habits of their kids to reduce exposure to nearby industrial facilities.”
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Toxic Chemicals and Children’s Health in North America