LITTLE ROCK, Ark. (AP) _ Traces of a banned pesticide found in milk that has been removed from stores in eight states have been detected in breast milk of some pregnant women, a health official says.

Federal investigators, meanwhile, will visit Arkansas, Missouri and Oklahoma next week to study the heptachlor contamination, which has forced farmers to dump thousands of gallons of milk.

Nearly 100 dairy farms have been quarantined in Arkansas and Missouri because cattle were found to have eaten feed contaminated with heptachlor, which was banned after scientists discovered it caused cancer in laboratory rats. Herds in Oklahoma are being tested.

The traces of heptachlor were found in breast milk from combined samples of 10 women, with the amount approaching 0.1 parts per million, the level at which a milk product must be removed from the market under federal regulations, said Dr. Stuart Fitzhugh, deputy director of the state health.

''We do not feel there is sufficient risk'' in a baby's drinking breast milk if the mother has stopped drinking cow's milk contaminated with heptachlor, he said Friday.

Health Department officials have recommended that those pregnant or nursing and children under a year old drink powdered milk because babies are particularly susceptible to toxins. Most other people can safely drink store- bought milk, they said.

Fitzhugh said the levels in the breast milk ranged from 0.07 to 0.097 parts per million.

But the women's physician, Dr. Greg Kresse of Eureka Springs, said the levels reached 0.1 parts per million, the FDA's action level.

Because the FDA has said heptachlor lodges in fat deposits and it could take at least six months to leave the body, Kresse said he has ordered all his patients to stop breast feeding.

''If the dairy products used during pregnancy were contaminated, just because she (the mother) stopped using dairy products doesn't mean that the breast milk was safe,'' he said.

Two companies, meanwhile, recalled 10,500 gallons of ice cream Friday after tests showed they were contaminated with the pesticide.

Bill Teer, the state Health Department's director of sanitation services, said Borden Dairy of Little Rock voluntarily recalled 10,000 gallons of ice cream in half-gallon square containers sold only in Arkansas. Sugar Creek Manufacturing of Russellville voluntarily recalled 500 gallons of soft ice milk sold to outlets in Arkansas and Louisiana, he said.

Teer also said 782 of Arkansas' more than 1,300 dairy farms have been notified they are free of contamination but 82 are prohibited from selling milk or cattle.

Four dairy farmers in Oklahoma were told last week to stop selling milk because of the contamination, but no farms are under quarantine, said Leslea Bennett Webb, an Oklahoma Department of Health spokeswoman.

The milk apparently was contaminated when the feed was sold to farmers in Arkansas, Missouri and Oklahoma. The company that sold the feed shut down March 6, when Arkansas officials announced the contamination. The company's owner has denied any wrongdoing.

U.S. Agriculture Secretary Richard Lyng said Friday a task force would visit those states next week.

Stores in the three states and in Texas, Louisiana, Kansas, Mississippi and Tennessee have stopped selling milk believed to have come from suspect dairies.

Some producers whose clean milk was mingled in tanks with contaminated products may have to dump the milk until tests prove their milk is safe, said Dr. Taylor Woods, Arkansas' state veterinarian.

''Along with our concerns about the public health implications of the heptachlor contamination, we fear its effects on farmers and agriculture,'' Lyng said. ''The economic consequences for dairy farmers could be considerable.' '