MERCURY IN THE ENVIRONMENT: THE HUMAN ELEMENT.

Abstract

This review is directed toward an understanding of the uses, sources, distribution, and toxic effects of mercury, and the main emphasis is on man as the distributor and recipient of mercury in the environment. The societal flow of mercury is initially considered. The main conclusion is that there is a need to pay more attention to the social implications of present use practices and to recycle much more effectively or develop alternatives to present mercury technology. The most important man-made sources of environmental mercury in the US are chlor-alkali plants, seed dressing agents, and probably smelting operations and the burning of fossil fuels. It has been found that whatever the source and compound of mercury introduced into an aquatic system, essentially only the highly toxic methylmercury form is found in the flesh of fish. The formation of methylmercury appears to be promoted by bacterial processes occurring within contaminated bottom sediments, and such sediments can slowly release their mercury burden as methylmercury for many years to come. Details are provided regarding the toxicity of mercury and its compounds. Appendices are included which consider aspects of the physical and chemical properties of mercury, evaluate analytical procedures used for mercury determination, discuss themore » chlor-alkali manufacturing process and procedures for reducing mercury losses, and provide some present and future needs with respect to our understanding and dealing with mercury in the environment.« less