Twenty-five years ago, Edward R. Murrow's documentary, "Harvest of Shame," aroused the public's conscience by revealing the ghastly conditions in which migrant field workers toil to bring a fresh and varied diet to the tables of this wealthy country. Since then, when migrant workers are found held in bondage or a migrant child dies from dysentery, public concern again flares momentarily. Congress may even tighten slightly the poorly enforced standards meant to curb the worst abuses. But there can be no better testimony to the ephemeral quality of this concern than last week's decision by the Occupational Safety and Health Administration to kill a long-awaited rule requiring that fresh water and toilets be provided to field workers.

There is a sick joke quality about the Labor Department's justification of its decision. OSHA Director Robert Rowland says that even if a federal standard had been set, it would have been laxly enforced. Well, he is certainly in a position to know how often his agency disregards its own rules. Mr. Rowland notes, moreover, that migrants in 13 states are already covered by some sort of sanitation standards. Perhaps he thinks that those in other states can simply move across state lines when they feel the urge. After all, they're migrants aren't they?

You should know that we are not talking about unnecessary frills. Thousands of field workers and their children are forced to toil for long hours in the hot sun with, at best, a bucket of contaminated water from which to drink and no access to toilet facilities. Numerous studies, including studies by Johns Hopkins University of workers on the nearby Delmarva Peninsula, have shown that, as a result of these primitive conditions, workers suffer high rates of infectious, parasitic and toxic diseases.

One expert, recently hired by OSHA to review all available evidence, concluded that parasitic disease is more common among U.S. field workers than among Guatemalan children. And because they have nowhere to wash their hands and must relieve themselves in the fields, these diseases are passed on to surrounding communities and the consuming public.

The compelling need -- on both humanitarian and public health grounds -- is no longer seriously disputed. Even the farm organizations, which have traditionally opposed federal standards, have muted their opposition. One official told reporter Ward Sinclair last week that "many of our members are prepared to put this behind us." Advocates for the farm workers are prepared to appeal OSHA's decision in court. Labor Secretary-designate William Brock should make sure that appeal isn't necessary. Mr. Rowland says that his agency has "higher priority standards" to enforce. What priority can be higher than treating all people in this country as human beings?