What is the main requirement of TSCA §4?

The main requirement of TSCA §4 (Toxic Substances Control Act §4) centers on the necessity for testing of chemical substances when risks are identified. This section grants the Environmental Protection Agency (EPA) the authority to require manufacturers and processors of chemical substances to conduct testing and provide information on the effects of these chemicals, specifically when there is evidence suggesting that a chemical may pose an unreasonable risk to human health or the environment.

This testing is crucial because it ensures that potential hazards associated with chemical substances are understood and managed proactively. By requiring such testing, TSCA §4 aims to mitigate risks before they result in harm, thereby promoting safety and sustainability in chemical manufacturing and use.

In contrast, the other answer choices address different aspects of chemical regulation or safety measures but do not capture the essence of the testing requirement under TSCA §4, which is fundamentally about assessing risks linked to specific chemicals through rigorous testing protocols.