Final answer:
Environmentalists like Clair Cameron Patterson worked for decades to reduce lead exposure, with key legislation starting in the 1970s which continued into the 1990s and beyond. The process involved changes to the Clean Air Act, the introduction of lead-free gasoline, and the implementation of regulations on lead in paint and other products.
Step-by-step explanation:
The efforts to outlaw lead as a public health hazard has been a long and arduous journey requiring the relentless work of environmentalists like Clair Cameron Patterson and others. The landmark legislation to reduce lead exposure began with the removal of lead additives in gasoline in the 1970s following the amendments to the Clean Air Act, which required a reduction in vehicle emissions and phased out leaded gasoline due to its harmful effects on human health and the environment. The movement continued throughout the decades with subsequent policies addressing lead in various forms, including the ban on lead in paints and limitations on lead in other products such as ceramics, as per the U.S. Food and Drug Administration guidelines.
However, it wasn't until significant studies were conducted by agencies such as the Environmental Protection Agency (EPA), along with the legislative changes that environmentalists were able to see concrete progress. In 1990, the Pollution Prevention Act further shaped the approach to environmental protection by focusing on preventing pollution rather than just controlling it, which included efforts to reduce lead pollution.