Two decades ago, the world was producing just half the amount of plastic waste it does today. Yet, despite efforts by environmentalists, only 9 per cent of plastic waste is successfully recycled, according to the latest Organisation for Economic Co-operation and Development report. June 5 is the UN World Environment Day, marked each year to highlight the importance of the environment. The majority of plastic waste ends up being dumped in giant landfill sites, burnt or left to pollute the environment. The OECD's first Global Plastics Outlook report shows that with populations growing and more people using and discarding the material, current policies to stop it from leaking into the environment are working. The average amount of plastic waste generated by one person each year varies from 221 kilograms in the US and 114kg in European OECD countries, to 69kg in Japan and South Korea. Often the main problem is poorly disposed of so-called macroplastics, such as plastic bottles, but microplastics are another major problem, which can leak into the food chain. Examples of microplastics are fibres from synthetic textiles, or microbeads found in personal hygiene products. According to UN figures, plastic pollution in the 1950s totaled two million tonnes. By 2017 it had risen to 348 million tonnes. It is a global industry valued at $522.6 billion. That is expected to double by 2040. In March, heads of state, environment ministers and other representatives from 175 nations endorsed a resolution at the UN Environment Assembly in Nairobi to curb plastic pollution. The intention was to forge a legally binding agreement that would tackle the problem by the end of 2024. About 80 per cent of plastic in seas gets there via rivers and coastlines, according to Our World In Data. The rest comes from marine activities such as fishing. Studies have suggested that just a handful of rivers can be blamed for the majority of plastic pollution entering oceans, with between 60 to 90 per cent of plastics coming from just 10 rivers. Asian rivers account for an estimated 80 per cent of ocean plastics, with the Philippines being responsible for about 30 per cent of the world's total. The Philippines' high contribution may be due to the amount of coastline it has, with most of its population living by or near the sea. The OECD report indicates that to reduce the amount of plastic entering oceans the problem of waste mismanagement needs to be tackled. Wealthier nations either incinerate or recycle their waste, or it gets sent to landfills that are well managed. Lower-income countries do not have this system, meaning their waste is more likely to end up badly managed and polluting the environment. <b>OECD facts on plastic waste:</b>