Chapter 13 - Chemicals in Waste: Household Hazardous Waste

Abstract

Household hazardous waste (HHW) is a term used to describe hazardous wastes entering the municipal waste stream. It represents a variety of waste types classified together based on the possession of hazardous properties. This chapter takes a look at the problems related to the disposal of chemicals and other hazardous substances used in the home. HHW is a small proportion of the municipal waste stream, but the potential risks to the environment and health are disproportionate to its size. Although estimates of the amount of HHW vary from region to region and across national boundaries, it generally comprises 1–4% of municipal solid waste (MSW). Internationally, most HHW is co-disposed with MSW to municipal waste landfills. Co-disposal of potentially hazardous wastes can lead to an increase in hazard status; not only are these substances potentially dangerous to the environment and health, but they can also induce changes in other waste streams by reacting directly with the waste or by altering the redox environment. Landfill simulations, based on current MSW disposal patterns, reveal the risk to the environment from leakage of potentially hazardous materials from landfills to be small but existent. There is a growing tendency for waste disposal authorities to make provision for the separate collection of many items of HHW. The increased cost of separate HHW collection and disposal must be considered alongside the new environmental and health risks posed by changes to disposal practice and the general trend of reduced hazardous content of most consumer goods.