Analysis of control methods: mercury and cadmium pollution.

Physical system conceptual models are developed to illustrate the various interconnecting pathways of metal flow. Economic use of mercury and cadmium, as representative toxic heavy metals, is inventoried, and the losses of each from the pathways of economic use are compared. Distinctions are made between high volume consumers and industries that are responsible for a large percent of total emissions or effluent loads. The pathways of the metals in the environment are traced via the conceptual models. A global mass balance is presented for mercury. The problem of high local concentrations vs. global metal flow is reviewed. Impacts of the metals on human health are categorized by type of effect. Available control strategies and abatement measures are evaluated with respect to the effectiveness of each on the problems of metal pollution, as illustrated by the physical models.