The US Environmental Protection Agency’s water pollution limits for some industry sectors are based on the capability of available treatment technology to control contaminants. Those technology-based water pollution limits for key parts of the chemical industry are decades old. Now, environmental advocacy groups are calling for the EPA to tighten these sector-specific pollution caps, called effluent limitation guidelines, which the agency sets under the Clean Water Act. Such a move is justified because water pollution control technology is more effective now than it was when the EPA established these restrictions, the Environmental Integrity Project and 60 other organizations say in a recent letter to the agency. For example, the EPA set water pollution limits for the paint formulation industry in 1975 and for the inorganic chemical sector in 1982 and has never revised them, the groups say in their letter. The EPA last revised limits for soap and detergent makers in 1975; carbon black manufacturers in 1978; organic chemicals, plastics, and synthetic fiber producers in 1993; pesticide chemical makers in 1998; and pharmaceutical producers in 2003. The environmental groups want the EPA to review and tighten effluent limits for another 50 industrial sectors as well.