Published Jan 1, 2016 8:00 AM
Assistant Professor Patrick Allard and his colleagues have found a new way to test the toxicity of everyday chemicals.
An estimated 80,000 chemical substances lurk in our environment, deposited there through industrial and agricultural waste and embedded in consumer goods ranging from food and pharmaceuticals to personal care products. And we don’t really know which ones are not harmful and which ones are, and to what degree.
Even as companies continue to produce new chemical compounds at a rapid clip, toxicologists and state and federal regulators agree that the conventional approaches to testing substances for toxicity have significant limitations.
Now there may be a better way to test the toxicity of the things we touch, feel and consume every day, courtesy of UCLA Assistant Professor Patrick Allard and his colleagues in the UCLA Fielding School of Public Health.
“When we say chemicals in the environment are safe, that’s only within the context of what has been studied,” says Allard. “But what has been studied is only the tip of the iceberg — there is still a great deal of uncertainty.”
Moreover, he adds, the current tests can accurately determine whether chemical compounds can cause genetic damage or cancer. “But when it comes to determining the effects on more complex concerns like reproduction and aging, this is where the technology lags.”
The Fielding team has developed an alternative approach that addresses the key shortcomings of the conventional methods by applying state-of-the-art automated technologies from genetics and other biological fields. The approach tests for the reproductive toxicity of chemical compounds using C. elegans — tiny worms that have served as model organisms for research in genetics and developmental biology, both because they’ve preserved many human reproductive processes and because they reproduce rapidly.
In the U.S., approximately 60,000 chemicals are exempt from being tested by the Environmental Protection Agency, having been grandfathered in by the Toxic Substances Control Act of 1976. And, Allard notes, while chemical companies are now required to test new compounds before introducing them into the environment, the limits of traditional methods leave many questions unanswered.
Allard’s method dramatically reduces the time and cost of such screening, while eliminating the need to test on rodents and other vertebrate animals. “With this approach, we can now simultaneously screen hundreds of compounds for their toxicity to the reproductive process, which can help to prioritize the chemicals that need further analysis,” he says.