More and better testing would protect us from chemical threats

New methods for testing the toxicity of chemicals could eventually provide better information about how chemicals affect human health, and might also reduce costs, speed up the testing process, and reduce animal suffering and death.

Toxic threats

Bryn Huxley-Reicher

Former Policy Analyst, Frontier Group

There are tens of thousands of chemicals being made across the U.S. that are put into products we use or are released into the environment. The amount we don’t know about their effects on human health is staggering.

Over the last few months, I have been working on a project examining the release of toxic substances into our waterways, which involved digging through the health effects of some of those toxics. I found that many substances have had little or no testing done for harmful health effects. And what testing has been done may not tell us enough about how exposure to toxic chemicals affects our health.

For decades, one of the primary ways we learned about the effects of toxic substances was through animal testing – a process that is slow and expensive and that recent studies related to the testing of pharmaceuticals suggest may not be fully accurate in assessing how chemicals affect the human body. 

One possible solution is in the emergence of new technologies that could allow scientists and environmental regulators to test more chemicals more quickly and, potentially, more accurately than methods based on animal testing.  

As far back as 2007, when the National Research Council wrote a report for the Environmental Protection Agency (EPA) about toxicity testing, new methods were showing progress, and today research is developing even faster. Alternatives to animal testing include cell-based studies (testing the effects of chemicals on cell cultures rather than whole animals); computer modeling (recent modeling projects have matched or beaten the predictive power of animal tests for health effects of medications); and “organs-on-chips” (systems of human cells, glass or silicon-based substructures and small machines to mimic the conditions of the human body that all work together to replicate a functional unit of an organ).

The U.S. is (slowly) beginning to adopt these new technologies into our approach to chemical testing. The House of Representatives recently passed the Food and Drug Amendments of 2022 which includes, among other things, changes to allow the Food and Drug Administration (FDA) to accept non-animal trials for safety and efficacy of medications. Similarly, a law passed in 2016 amended the Toxic Substances Control Act, which regulates chemical production and disposal among other things, to direct the EPA to reduce and replace animal testing of chemcials as much as possible and to develop and validate alternative testing methods and strategies.

That work on alternatives to animal testing is well underway, and some alternatives have already been shown to provide better information than animal testing and so are approved as replacements. Since the goal of these testing alternatives is to provide lower-cost, faster and more reliable information on the effects of chemicals, further development and validation will allow the EPA to do a better job on its massive tasks of screening all new chemicals and evaluating existing chemicals for safety – a process that is currently happening very, very slowly.

It is important, however, to make the transition to new forms of toxicology testing carefully. One factor to consider is that part of the EPA’s duties in testing chemicals is determining the impact of those chemicals on the environment and non-human animals, so new methods have to be able to provide useful information about those impacts. A second consideration is that the goal of moving to these new forms of testing is to get better information about chemicals with less time and lower costs, and that such testing is only worthwhile if it can meet or improve on the quality and kind of information that current testing strategies provide.

Recent advances in alternatives to animal testing – coupled with the EPA’s mandate to test all new chemicals and evaluate existing ones – are welcome changes. We shouldn’t be making and using thousands of substances whose health effects we don’t know. We should test chemicals, and restrict their use in ways that protect public health. These new advances mean we could soon have a much clearer picture of how the substances to which we are exposed affect our health. That those same developments could (with further improvements, validation and broader adoption) reduce or eliminate animal suffering and death, improve health outcomes, speed up the testing processes for chemicals, and reduce costs is all the better.


Bryn Huxley-Reicher

Former Policy Analyst, Frontier Group

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