Air Date: Week of June 15, 2007

Dr. Gina Solomon, senior scientist at the Natural Resources Defense Council. (Courtesy of Dr. Gina Solomon.)

The EPA announced that it will begin testing pesticides for human toxicity. But how do you test the 80,000 chemicals currently on the market in a timely and safe manner? Host Steve Curwood talks with Gina Solomon, senior scientist with Natural Resources Defense Council, about how the EPA might follow through on its testing commitment.

Transcript

CURWOOD: It’s Living on Earth. I’m Steve Curwood. We have two developments to tell you about this week on the topic of testing chemicals for toxic effects. In the first, the National Academy of Sciences is recommending that federal agencies like the EPA adopt sweeping changes to the ways that they test for health effects of chemicals. The goal is for these tests to be faster and cheaper, provide far more information, and be done with little or no use of laboratory animals.

In the second, related development, the EPA has just announced that it will finally begin testing 73 common pesticides for effects on the human hormonal, or endocrine system. This assessment of so-called hormone disruptors has been years in the waiting and finally came about in part because of a lawsuit filed by the Natural Resources Defense Council. Dr. Gina Solomon is a senior scientist with the NRDC, and she joins us now on a line from San Francisco. Dr. Solomon, can you tell us briefly what are the hormone disrupters and why we should be concerned about them?

SOLOMON: Hormone disrupters are chemicals that don’t belong in our bodies that interfere with the normal action of our hormones. These natural hormones guide infant development. They also guide many of our day-to-day life functions. So, messing with them is not a good idea.

CURWOOD: The Environmental Protection Agency has announced that they are going to start testing some 73 pesticides that people are most likely exposed to. How much of a victory is this for the public health community?

SOLOMON: One important point here is that EPA was required to start testing chemicals to see if they are endocrine disrupters eight or nine years ago. NRDC and other groups brought a lawsuit against EPA when it missed the first deadline required by Congress. EPA then, as part of the settlement of that lawsuit, agreed to start the testing process. They agreed to do that by 2002. They haven’t started yet, and they’ve only now announced a draft short list of chemicals that they’re thinking about testing. So, we’re a long ways from being able to say this is a step forward.

CURWOOD: Dr. Solomon, I want to turn now to another development in the news and you’re intimately involved with this. You’re on a panel at the National Academy of Sciences that’s looking at the whole question of testing for toxicity. Can you explain why it is that we need to look at this? What’s wrong with the way we test toxic chemicals today?

SOLOMON: The horrible delays with the EPA endocrine disrupter program are emblematic of where we stand with toxicity testing in general today. EPA is still struggling to get out of the last century. They’re very slow at getting new programs off the ground. Most of the chemical tests that are required are looking for crude end points such as death in a laboratory rat, obvious tumors, birth defects, or severe toxicity of internal organs. There are a lot more subtle ways and earlier markers of toxicity that we could be focusing on, but we’re not there quite yet. And the NAS panel is proposing moving in a much more upstream direction where we’ll find hints of toxicity far before it really occurs.

CURWOOD: Why would that be of help?

SOLOMON: The problems with toxicity testing today are that it costs a lot of money, takes a lot of effort to do even a small number of chemicals, and does not provide information about low-dose effects, effects of chemical mixtures. The new approach that the NAS is proposing would help deal with some of these problems by looking at pathways toward toxicity that can be tested just in cell systems in the laboratory.

CURWOOD: So, in other words, instead of looking for the flat tire, you’re looking for, maybe, a beginning of the erosion of the rubber?

SOLOMON: We would be looking for week spots in the rubber and spots where there might be a tiny hiss of air coming out. But we’re not waiting for the flat tire anymore.

CURWOOD: Now, as I understand it, these proposed methods of doing testing would perhaps take away the need to use animals. How would that happen?

SOLOMON: The NAS committee envisioned that some day, and it’s going to be many years in the future, there will be very little use of animals in toxicity testing. That’s because once we’re focusing on pathways we can actually get down to the cell level. And when we see that in cells a chemical is disrupting a pathway that can lead to say cancer, or birth defects, or neurological harm, we don’t need to know more. Once we know that that pathway is interfered with, then that chemical would need to be controlled to the point where it’s no longer interfering with that pathway.

CURWOOD: This sounds like a revolution for the field of toxicology, but if we’ve been testing chemicals more or less the same way since chemicals were introduced, I imagine it’s going to be, well it’s going to be kind of tough to change the whole culture and system of doing this. What are your expectations for the future of chemical testing?

SOLOMON: There’s already a revolution underway in chemical testing. There are organizations like the National Toxicology Program that are pioneering approaches that are just like the ones I’m describing. The next step of that revolution is to bring it into an arena where it can be useful for protecting public health and the environment.

CURWOOD: I take it you’re really excited about this prospect.

SOLOMON: I think that this proposal has a lot of merit in getting us out of some of the traps that we’re in right now, especially the toxic ignorance trap, where we know so little about so many chemicals. I also think that this promise is many, many years away, probably decades away. There’s a long road from here to there and I’m hoping that we can actually embark on that road and make these changes.

CURWOOD: Dr. Gina Solomon is a senior scientist with Natural Resources Defense Council and on the National Academy of Sciences Committee on Toxicity Testing and Assessment of Environmental Agents. Thank you so much.

SOLOMON: Thank you.

[MUSIC: Clogs “Medley (Excerpt)” from ‘Lantern’ (Brassland - 2007)]

CURWOOD: We asked the EPA about the lengthy delay in testing hormone-disrupting chemicals. Jim Gulliford, assistant administrator for the Office of Pesticides and Toxic Substances, did not reply directly. Instead he sent a written statement saying that the EPA is quote-- “a leader in endocrine disruptor research” and that the screening effort “will provide the agency with a more comprehensive assessment of a chemical's ability to affect the endocrine system."

 

Links

Natural Resources Defense Council Website

EPA Website

EPA list of pesticide chemicals they plan to test