The Environmental Defense Fund yesterday asked the Environmental Protection Agency to bar a widely used chemical found in wheat, gasoline and some fruits, on grounds that it has caused cancer, sperm damage and birth defects in tests on animals.

The chemical, ethylene dibromide (EDB), is a close cousin of a pesticide linked to more than 72 cases of sterility in male chemical workers, and is manufactured at one of the plants where sterility has been documented.

EDB is used as a substitute for this pesticied, dibromochloropropane commonly known as DBCP. Dow and Shell Chemical companies, the only two domestic manufacturers of DECP recalled all outstanding stocks of that pesticide after medical tests recorded low sperm counts in workers at four different plants.

But EDB is more widely used than DBCP, both as a soil fumigant and as an antiknock additive in gasoline. And it has produced far more severe health damage in tests on mice, bulls and chickens.

In a strongly worded letter, the defense fund, a nonprofit group, complained that federal regulators have ignored repeated warnings about EDB health hazards, and it urged action be taken to "eliminate or drastically reduce human exposure to it."

The fund said the Environment Protection Agency, which is supposed to regulate pesticides, "has a duty to protect public health against such unreasonable adverse effects as cancer, sterility and birth . . . any further delay in regulating EDB would be illegal as well as unconscionable."

More than 300 million tons of EDB are manufactured each year at six plants in the United States. About 90 per cent of the chemical is used in gasoline, and EPA studies have reported large traces of it near highways and gasoline stations. The rest is used in pesticides of various sorts, and tests have picked up residue of it in wheat stored in bins where its has been sprayed, as well as on vegetables and fruits.

An estimated 8,800 enterminators and fumigators, several hundred chemical workers and hundreds of gasoline service station workers come in almost daily contact with it.

According to studies by the National Cancer Institute and the National Institute of Occupational Safety and Health, it has produced stomach cancer in 76 per cent of rats and 87 per cent of mice tested and damage to central nervous systems of some test animals.

When fed EDB, hens have been found to produce fewer, smaller and less fertile eggs. Semen from bulls given oral doses of EDB has also shown signs of damage.

The compound has produced severe vomiting, kidney and liver disorders and ringing in the ears in humans tested. No signs of cancer, which often takes 10 years or more to detect, have been found in these human tests.

Industry studies have concluded that 20 parts of EDB per million parts of air is a "safe" level for workers, and EPA has long accepted this level in its regulations.

The agency has not toughened regulations, despite repeated requests to do so since the National Cancer Institute issued a cancer alert on the compound in 1974.

Yesterday, Edwin Johnson, head of EPA's pesticide division, said the agency is examining EDB along with DBCP under what is called its rebutable presumption process, and hopes to have a finding by mid-September. This process could result in EPA's banning the chemical, but this could take nine months or more.

Maureen K. Hinkle of the Environmental Defense Fund asked the agency to take a more direct route, and take a more direct route, and take it off the market with an emergency suspension order.

Meanwhile, the Occupational Safety and Health Administration announced it was inspecting air quality and health records at a Dow Chemical plant in Magnolia, Ark, where both EDB and DBCP are manufactured. In addition, congressional and environmental sources were raising serious questions about the federal government's approach to dangerous epsticides.

Rep. David Obey (D-Wis) who has had a long interest in the subject, said it takes nothing more than the most cursory review of government spending on preventive health to understand why workers and the general public continue to be exposed to potentially hazard chemicals such as DBCP and EDB."

He said NIOSH, the government agency charged with identifying hazards in factories, "has a budget that amounts to less than 60 cents per worker per year."