Imports generally have their plastic packaging removed at customs, officials say, unless doing so would damage the goods. In that case, stores are required to remove the packaging before handing the merchandise to customers.

Food wrapped in cellophane is allowed only in hotels, and only if it does not leave the premises.

Biodegradable bags are allowed only for frozen meat and fish, not for other items like fruit and vegetables because such bags still take as long as 24 months to decompose, the government says.

Potato chips and other foods packed in plastic are allowed only if the companies making them are approved by the government — after showing a detailed business plan that includes how they plan to collect and recycle their bags.

The results of Rwanda’s efforts are evident in this clean country, but they may not be easy to replicate. In the United States and Europe, for example, there is a dispute between environmentalists and representatives of the plastics industry who say that bags made of alternative materials, like cloth, have a bigger carbon footprint than plastic ones and aren’t as environmentally friendly as people think. Plastic bags should be reused and recycled instead, they argue.

The authorities in Rwanda brush off criticism about the absence of similar debates in their country. The rules here are based on extensive scientific research and public surveys, they say. And their enforcement is more easily accepted in a country with authoritarian tendencies and little room for dissent.