If they specialize in occupational or community medicine, they ll be helpful with the health effects of chemicals and with health surveys. Engineers are trained to design things. Environmental engineers, sanitary engineers, and chemical engineers might be especially useful in your campaign. Environmental scientists and ecologists have a broad background including biology, chemistry, engineering, and epidemiology. They can be useful in evaluating pollution problems.
Epidemiologists study the patterns and causes of diseases in population.
They are useful if there are questions about health surveys. Geologists and hydrogeologists study issues of rock, soil, surface water, and groundwater. They are useful for water pollution and hazardous waste questions. Toxicologists study the toxic effects of chemicals.