Final answer:
Regulatory agencies such as OSHA and the EPA are chiefly responsible for setting safe exposure limits for materials, by establishing health and safety regulations and standards. The dose-response curve and toxicokinetic studies inform these limits. For products like cosmetics, companies are primarily responsible for safety, with the FDA providing oversight without requiring pre-market approval.
Step-by-step explanation:
The primary responsibility for determining safe limits for chronic exposure to materials resides with regulatory agencies such as the Occupational Safety and Health Administration (OSHA), which has the authority to issue workplace health and safety regulations, including limits on hazardous chemical exposure. Factors such as the dose-response curve, which relates the dose of a substance to the individual's response, and the margin of safety, based on efficacy concentration and exposure data from toxicokinetic studies, play a critical role in establishing these limitations. In addition, the Environmental Protection Agency (EPA) establishes primary and secondary standards to address human health and environmental impacts, respectively.
In cases of environmental exposure, such as with drinking water contamination by naturally occurring substances or through industrial activities like mining or agriculture, it is the responsibility of the government, through entities like the EPA, to set and enforce the recommended levels for pollutants. Meanwhile, in the realm of product safety, such as with cosmetics, the industry predominantly ensures the safety of its products, with oversight authorities like the Food and Drug Administration (FDA) stepping in to protect public health when needed. However, the FDA does not usually require pre-market approval, leaving companies to self-regulate unless significant issues arise.