Organotin Antifouling Hull Paints and the U.S. Navy--A Historical Perspective

Abstract

An interim finding of no significant impact for the U.S. Navy's fleetwide implementation of tributyltin (TBT) containing organotin antifouling hull paints appeared in the U.S. Federal Register of 21 June 1985. This finding was based on an environmental assessment and committed the Navy to (1) slow implementation of the painting program, extending over a 10-year period; (2) use of paints with release rates not greater than 0.1 \mu g TBT/cm2/day; (3) environmental monitoring at major Navy harbors, ensuring a target average concentration of 50 ng TBT/L or less; and (4) a commitment to update the environmental assessment in 1988. The paints intended for use by the Navy were registered by the U.S. Environmental Protection Agency and were used widely by recreational and commercial vessels. The public announcement by the Navy of its intended action resulted in a nearly unanimous negative response from Federal, state, and private agencies. This paper describes the U.S. Navy's research effort, which demonstrated the unique operational and economic benefits provided by these paints for its combat ships; the consequences of preparing the environmental assessment for Fleetwide implementation; the importance and complexity of TBT paint release rates; the response of the environmental community to potential risks of TBT use; concerns and action taken by the U.S. Congress and the U.S. Environmental Protection Agency; the role of water column monitoring and laboratory bioassays; the enactment of regulatory legislation by states on both coasts; and the Navy's leadership in establishing a strategy for the environmental management of TBT.