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"But this is a story of a different kind of flower, which also comes in many colors but lacks the beauty of the many varieties discovered in nature by Ms. Sapieha. All over Nairobi, and all over Africa, are ugly artificial blooms that mar the landscape and that environmentalists want plucked up and removed.
These flowers are cheap, thin plastic bags that are tossed to the ground by consumers. This kind of litter has reached a critical mass in Kenya - clogging streams, choking animals and piling up into little mountains of disease. These bags are different from the ones that Westerners carry their groceries in from the neighborhood supermarket; the Kenyan bags are so thin they barely hold a few mangoes or a few pounds of corn meal without tearing. Their delicate nature makes reuse impossible and leads to their frequent introduction into nature, where experts say they tend to remain without breaking down for somewhere around 1,000 years. The bags are so pervasive in this part of the world that many have taken to calling them "African flowers," as if they were local varieties of roses or bougainvillea. "You can't miss these bags," said Clive Mutunga, an environmental economist in Kenya who is seeking to clean up the mess. "It's gotten to the point where it's almost become our national flower."
Wangari Maathai, the assistant environmental minister in Kenya and 2004 Nobel Peace Prize winner, says the sacks provide a breeding place for malarial mosquitoes, helping spread one of the continent's major killers. "I'm not saying don't use plastics at all," Dr. Maathai said recently as she extolled the virtues of more homegrown bags, like those made of sisal or cotton, or the traditional baskets, which were what people used before plastic came along.
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."
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http://www.nytimes.com/2005/04/07/international/africa/07nairobi.html?pagewanted=all