UNITED NATIONS - Across southern Africa, an estimated 13 million people face the threat of severe hunger. Yet much of the UN emergency food aid shipped to the region this summer was slowed by a raging public debate over the genetically modified grain it contained.

In a half-dozen countries, consumer groups, lawmakers, and government officials say that, while genetically modified food may feed the starving now, it may harm human health in the future and hurt agricultural trade in their region.

Debate over genetically modified food aid has also occurred in India, Bolivia, and other countries. And analysts say that such concern is certain to grow, as the need for famine relief swells and as more crops are genetically modified.

''We're just at the beginning'' of the debate, said Calestous Juma, director of the Science, Technology, and Innovation Program at Harvard University's John F. Kennedy School of Government.

Indeed, the question is likely to be an issue at the UN's World Summit on Sustainable Development, which opens Monday in Johannesburg.

South Africa, a major producer of genetically modified crops, has sufficient food. But six of its neighbors - Zambia, Zimbabwe, Malawi, Mozambique, Lesotho, and Swaziland - are facing dire food shortages.

Prolonged drought, corrupt government policies, and mismanagement of food supplies have caused the food crisis. The UN World Food Program estimates that 1.2 million tons of grain is needed to feed nearly 13 million people in the region.

Aid has arrived, 132,000 tons so far from the United States, with 75,000 tons en route. This week the US government agreed to raise its total contribution to around 500,000 tons by the end of the year, half the total UN contribution.

But US food aid, like the food Americans buy in the supermarket, combines regular and genetically modified food.

According to the US Department of Agriculture, 30 percent of American corn and 70 percent of soybeans, both staples of food aid, are genetically modified. That means the genes have been altered to make crops grow better or be more resistant to pests.

Malawi, Swaziland, and Lesotho, the smallest countries in the region, accepted the food donation, most of which came from the United States.

But Zimbabwe, Zambia, and Mozambique protested that the aid contained genetically modified food. They feared that the modified grains could mix into their crop seed, change the genetic makeup of the food they grow, and threaten future exports. Some activists also worry that the modified grains could present health risks, such as allergic reactions.

Last week, Zambia announced that it will refuse any genetically modified food aid. Ending days of debate, officials said they would import regular grain for sale and for food reserves, and they have appealed for food aid that does not include genetically altered grain.

''We would rather starve than get something toxic,'' Zambian president Levy Mwanawasa told Sky News recently, The UN estimates that 1.75 million people face starvation in Zambia.

After heated internal debates that delayed the delivery of food aid, Zimbabwe and Mozambique agreed to accept the genetically modified grain. But both countries will pay to have the grain milled before it is distributed, to reduce the chance that the modified grain could be used for planting and contaminate native varieties.

Furor over food aid is hardly new in developing or war-torn countries, where gestures of largesse can be held hostage to local politics. Questions of trade and the legacy of colonialism influence the debate.

In Zimbabwe, which exports grain and beef to the European Union, trade became a major stumbling block to accepting genetically modified food aid. The European Union has restrictive policies about genetically modified food. Only 18 such agricultural products are allowed in the EU; another 14 have been pending approval since 1998.

Zimbabwean scientists and others feared that if kernels of genetically modified grain arrived and were planted, gene-altered pollen would taint the country's entire harvest, imperiling exports.

Faced with losing trade or feeding the estimated 6 million Zimbabweans who will face starvation by winter, the country opted to accept the genetically modified corn, provided that it was milled so it could not be planted.

Still, ''we'd prefer we receive no GM food at all,'' Emmanuel Gumbo, a spokesman for the Zimbabwean Mission to the United Nations, said of genetically modified food.

Debate also arose in Zimbabwe, Zambia, and Mozambique over whether genetically modified food is safe and whether the United States was exporting products it didn't want.

There is little consensus on the issue among scientists, consumer groups, and legislators.

Such food ''is among the most tested food in the world,'' said Jason Lott, a bioethicist at the University of Witswatersrand in South Africa. ''If it wasn't safe for the average consumer in the US, it wouldn't be on the market.''

But Michael Hanson of the US-based Consumers Union, which advised Zambian consumer groups, warned that appropriate tests have not been done. ''You can say there's no hard data saying it is unsafe,'' he said, ''but that's because there's a paucity of data. ''

Even more divisive are questions about whether genetically modified food is somehow second best.

''The feeling is, the West tends to dump its second-grade goods on us,'' said Winston Hide, professor of biotechnology at the University of the Western Cape in South Africa.

US officials say the critics and consumer groups who have provoked the outcry in Zimbabwe, Zambia, and Mozambique are putting their own agendas ahead of people's empty stomachs.

''If we don't deliver food in time, people will starve,'' said Andrew Natsios, director of the Agency for International Development at the US Department of State in Washington, D.C. ''These groups are putting poor people's lives at risk.''

But the criticism is not confined to southern Africa. In Bolivia, citizens groups working with the US-based group Friends of the Earth complained earlier this year after they tested USAID food aid and discovered it contained genetically engineered Starlink corn, which is prohibited for human use in the United States.

In June, Environmentalists in Nicaragua also complained that genetically modified food was in the aid sent to help some 700,000 Central Americans suffering drought-related hunger.

The World Food Program, which accepts donations of money or food and then distributes aid, says that for now there is little it can do to respond to such complaints. Donations are down: The agency has only 23 percent of what it needs to feed the hungry in southern Africa, and that includes the American-donated genetically engineered food.

''This debate won't undermine food aid as an enterprise,'' noted Joel Charney, vice president for policy at Refugees International, which is based in Washington, D.C. ''But it will make it a lot more complicated.''

© Copyright 2002 Globe Newspaper Company

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