But the authors warn that far more needs to be done to reduce the vast flow of plastic into rivers and oceans.

What’s more, they say, good policies to curb plastic waste in many nations have failed because of poor enforcement.

Action against plastic waste has many drivers across the world. In the UK it has been stimulated by media coverage.

In many developing countries, plastic bags are causing floods by blocking drains, or they’re being eaten by cattle.

The report says policies to combat plastic waste have had mixed results. In Cameroon, plastic bags are banned and households are paid for every kilo of plastic waste they collect, but still plastic bags are being smuggled in.

In several countries, rules on plastic exist but are poorly enforced.

The report presents an A-Z of 35 potential bio substitutes for plastic. It runs from Abaca hemp (from the inedible banana Musa textilis) to Zein (from a maize protein).

The list includes rabbit fur, sea grass and foam made with fungus. It mentions QMilch, a firm that create casein textile fibres from waste milk.

It also highlights Piñatex, a plastic alternative made from pineapple leaves.

Some policy-makers, though, are wary about hyping the potential of bio alternatives.

Early optimism by some environmentalists about biofuels backfired when rainforests were felled to grow palm oil to fuel cars.

Erik Solheim, head of UN Environment, said: "The assessment shows that action can be painless and profitable – with huge gains for people and the planet that help avert the costly downstream costs of pollution. Plastic isn’t the problem. It’s what we do with it.”

The report says levies and bans – where properly planned and enforced – have been among the most effective strategies to curb plastic waste.

But the authors also cite a fundamental need for broader cooperation from business, including obliging plastic producers to take responsibility and offering incentives to stimulate more recycling.

National actions include:

 Botswana – retailers charged but no enforcement and controls "failed".
 Eritrea – ban on plastic bags and dramatic decrease in drain blockage
 Gambia – ban on plastic bags, but "reappearance after political impasse"
 Morocco – bags banned – 421 tonnes of them seized in one year, virtually replaced by fabric
 Bangladesh – ban on bags but lack of enforcement
 China – was using three billion bags a year pre-2008. Now there is a ban on thin bags, use decreased 60-80% in supermarkets but not in markets.
 Vietnam – bags are taxed but still widely used. Government considering increasing tax five times
 Ireland – tax led to 90% fall in consumption
 Kenya – cows ingested an average of 2.5 bags in their lifetimes. Now there's a total ban, and fines and a four-year jail term for making, importing or using them

Source: BBC