"Nonanimal approaches have been available for years, but regulators are slow to adopt them"
"In early 2016, the US Environmental Protection Agency set an immediate goal to reduce the number of animals used to test the toxicity of pesticides. The agency claims that it is making significant progress toward meeting that goal, but manufacturers are still using tens of thousands of laboratory animals each year to demonstrate that new pesticides entering the US marketplace meet safety standards.
The primary way the EPA’s pesticide office has reduced the use of animals is by granting waivers for certain tests. The agency has been much slower to identify and validate nonanimal methods to replace in vivo animal studies.
One of the biggest hurdles to replace in vivo animal studies with in vitro human-relevant tests is a lack of correlation between the results of human and animal studies. Toxicologists know that animal studies are not always reproducible and useful for predicting adverse human health effects. Even so, animal studies are still the gold standard that scientists try to model and replicate with in vitro systems. A growing group of scientists is calling for that to change."