Southeast Asian countries are seriously polluted by the sea. Their goal is to curb plastic waste.

Thanaboon Somboon, a Thai zero waste advocate, carries what he calls "weapons" everyday when he goes out, including reusable shopping bags, coffee cups and stainless steel straws to combat disposable plastics.

"I saw the news of garbage spread all over the world, marine animals died from eating plastic, and I felt I had to do something," said the 48-year-old entrepreneur, who led an online community of more than 20,000 people in search of a waste-free lifestyle.

Indonesia, the Philippines, Vietnam and Thailand, members of ASEAN, are among the countries that throw most plastic waste into the ocean, according to a report co-authored by Ocean Conservancy in 2015.

Wijarn Simachaya, Permanent Secretary of Thailand's Ministry of Natural Resources and Environment, said: "Every ASEAN country believes that marine debris is a common problem and we must deal with it urgently."

According to the United Nations Environment Programme (UNEP), up to 5 trillion disposable plastic bags are used worldwide every year. According to the report, 300 million tons of plastic waste are produced annually, of which 8 million tons eventually flow into the ocean, killing marine life and entering the human food chain.

Thailand produces about 2 million tons of plastic waste annually, of which only 25% is recycled. The remaining garbage will be incinerated or landfilled, and about 50,000 to 60,000 tons of it will leak into the ocean.

Environmentalists praised the initiatives of some major retailers to reduce the use of plastic bags, but said most businesses would not take action unless there were stricter policy measures.