A recent study by the National Environmental Management Authority and the Kenya Institute for Public Policy Research and Analysis estimated that more than 100 million light polythene bags, many of them thinner than 30 microns, are handed out each year in Kenyan supermarkets, which is more than 4,000 tons of the bags every month. The study recommended banning the thin bags, which are believed to make up most of the litter. Other bags, it said, should be taxed to provide a financial incentive for bag manufacturers to come up with more environmentally friendly alternatives.

The tax could then go to support recycling efforts, which are not common in Africa, says the report, which was financed by the United Nations Environment Program.

The report notes that there would be some job losses if Kenya outlawed the manufacture of plastic bags, which is a booming industry here that supplies all of East Africa. But it notes that other jobs would probably be created among cotton bag manufacturers. Nairobi's street children and others might also earn some income from picking up plastics if a recycling program was started.

Kenya, which profits from the many tourists who come to witness its pristine landscape, is not the first African country to try to clean up its act. Rwanda recently banned plastic bags that are less than 100 microns thick and it took such a tough enforcement stand that the police would dump out the goods on the road if they found shoppers with them. "The black plastic bag has disappeared from Kigali," the United Nations Environment Program said, referring to the capital of Rwanda in a recent statement on the issue.

South Africa has also imposed a ban on bags thinner than 30 microns, which are so flimsy that one's finger can easily pierce them. Other more durable bags are taxed by South Africa, which gives some of the revenue to a plastic bag recycling company.

Somaliland, a breakaway state in northwestern Somalia, outlawed plastic bags as well, although passing the law has not appeared to put much of a dent in the problem there. In local parlance, the plastic bags there are called "Hargeisa flowers" because they pop up everywhere in and around Hargeisa, the Somaliland capital. "The bags have not only become an environmental problem, but also an eyesore," Abdillahi Duale, Somaliland's information minister, recently told the United Nations News Service.

Eliminating the bags is regarded primarily as a task that falls on shopkeepers. Nakumatt Holdings, one of Kenya's largest supermarkets, has said it backs the effort to clean up the country's landscape.