Photo/IllutrationMountains of plastic garbage await processing at a facility in Tokyo's Ota Ward. (Ryo Ikeda)

The Group of 20 summit in Osaka agreed last month to work toward zero plastic waste entering the world's oceans by 2050.

This was the first time an international target has been set to tackle the damage caused by plastic waste to marine resources.

As the summit host nation that brokered this agreement, Japan bears the responsibility of continuing to lead the world in this cause.

But first, Japan must get its act together, particularly in conjunction with issues related to climate change.

With 86 percent of its plastic waste being "effectively utilized," Japan is said to be advanced in the field. However, this impressive figure owes largely to plastic rubbish that is incinerated for so-called thermal recycling, which is about utilizing thermal energy produced by incineration to generate power and also supply hot water.

But in the rest of the world, this form of one-time utilization of heat is not considered "recycling" proper and, therefore, not factored into the percentage of recycled plastic trash. This lowers Japan's real plastic recycling rate to a modest 27 percent, which falls short of the European Union average.

Japan needs to take a hard look at this reality.

One thing to be borne in mind is that burning plastic waste invariably generates carbon dioxide, and whether the heat is utilized or not is irrelevant.

Under the Paris Agreement that calls for drastic cuts in greenhouse gas emissions, there is no way Japan's continued incineration of massive volumes of plastic trash can be condoned.

The Basel Convention--a treaty that controls the movement of hazardous waste from one country to another--was amended in May to render it harder for nations to ship their plastic waste to Southeast Asia and other regions.

It would be out of the question for any nation to seek an easy way out by simply burning the trash. Urgent action is needed to prevent such an outcome.

The solution lies in thorough enforcement of the "three R's"--reduce, reuse and recycle. If some plastic trash still remains despite every effort, then only in such an eventuality should anyone be allowed to burn it and utilize the heat. In short, incineration must be considered the last resort.

Of the three R's, the most vital is obviously "reduce."

Because the bulk of household plastic refuse is collected by local governments with taxpayers' money, the recycling costs borne by businesses are limited. And it is for this reason that single-use plastic items are mass-produced at low cost and mass-consumed, perpetuating the cycle of huge volumes of these items being tossed and burned.

This vicious cycle must end.

One policy worth considering would be to increase the responsibility to be borne by businesses, so that the prices of plastic items will go up and make them less desirable to consumers.

Also vital are attempts to replace them with eco-friendly biomass plastic versions, and encourage corporations and consumers to embrace a plastic-free lifestyle.

We must remind ourselves that if Japan just sits and does nothing, it will only find itself left behind while the rest of the world goes plastic-free in the fight against global warming.

--The Asahi Shimbun, July 31