Convenience store operator Seven-Eleven Japan Co. said Monday it will start selling all of its rice balls in wraps made of biomass plastics, possibly from July, as it aims to reduce the use of fossil-fuel-derived materials.

The company’s move, affecting the some of 2.2 billion onigiri rice balls it sells annually, comes as more firms adopt plant-derived plastics amid the government’s calls for reducing plastic waste to prevent marine pollution.

By replacing part of the wrapping with a sugar cane-derived material, Seven-Eleven estimates it can reduce the use of plastic by 260 tons and cut carbon dioxide emissions by 403 tons a year.

In a similar move, convenience store chain operator FamilyMart Co. has replaced its containers for cold noodles with those made from recycled plastic.

Ohsho Food Service Corp. also announced last week it will replace its plastic straws with biodegradable ones and plastic spoons with biomass plastic ones at its 729 restaurants nationwide from next month.