IN a dangerous attempt to protect their crops many African farmers are misusing highly toxic imported pesticides, some of which are banned by the developed nations who export them, African and Western experts say.
In Mali and other African states, international and domestic efforts to educate farmers in the proper use of pesticides and encourage alternative ways of fighting insect pests are gradually expanding.
But the scope of toxics misuse in Africa is immense, experts point out.
Malian farmers frequently apply pesticides with their bare hands or unsafe equipment. Empty pesticide containers are sometimes reused for food or water storage. Farmers often do not know which pesticide they are using or what the health risks are.
Poor labeling, lack of protective clothing and equipment, insufficient training, high illiteracy rates among farmers, and little education about related health hazards are some of the causes of this abuse.
Pesticide misuse is "a widespread problem throughout Africa," says Vickie Schoen, an American expert on pesticides who has worked in seven African countries, including Mali, over the past 20 years. "Local medical officials have no training in the recognition of pesticide poisoning."
The United States has been a major supplier of pesticides to Mali; farmers here relied heavily on American products, including toxic pesticides restricted in the US, during a major grasshopper and locust outbreak from 1987 to 1989.
According to the US Agency for International Development (USAID), more than 100,000 liters (26,000 gallons) of toxic, obsolete pesticide stocks from several countries remain in Mali. Some of the chemicals can be incinerated or shipped to developed countries for safe disposal.
One USAID project proposal for promoting the safe use of pesticides in Mali says "effects of pesticides on both humans and the environment are not directly observable for several years. Nerve damage, respiratory problems, and cancer are some of the conditions associated with pesticide misuse."
When asked about health problems associated with pesticide misuse, however, a USAID official here said a Malian government report did not indicate "any significant problem." A Malian agriculture official gave a similar reply.
But Diane Schumacker and Tappan Heher, two Peace Corps volunteers working in Mali, offer a different view.
Although large drums or sacks of imported pesticides arrive in the country with warning labels, those warnings usually do not reach the farmers, they say. Wholesalers and retailers repack the pesticides into smaller portions that do not bear cautionary labels.
At a private roadside stall here, just across from a government agriculture office and warehouse, a Malian sells unmarked, clear plastic bags of what he identifies as DDT (dichloro diphenyl trichloroethane), a powerful but environmentally damaging insecticide restricted in the US. It is for use on "clothing and mattresses," the salesman says.
In the government warehouse, dirty, torn labels on some bags of pesticides are nearly impossible to read. "It's not very visible," says a government employee.
One pesticide container from New Jersey arrived empty, the employee said. "We washed it" and are using it to store drinking water, he said.
One alternative to chemical pesticides USAID is promoting here to combat grasshopper infestations involves paying villagers to dig up and burn the insects' eggs.
In 12 villages, 11 tons of eggs were destroyed in the first six months of 1991, a USAID official says. As a result, the threat was "wiped out" in that area.
Sylvester Lassana Diarra, a Malian agriculture official, says farmers and others have gradually adopted safer methods of applying pesticides.
"Resources in these African countries are very limited," Mr. Diarra says. Mali's government, one of the poorest in the world, is working through farmer cooperatives to teach pesticide safety.
But even when risks of a pesticide are known and proper equipment is not available, farmers may still choose to use the pesticide, Diarra says.
"When the farmer is faced with a blight, and may lose his harvest, what is he to do?" he asks.