Amazon said its plastic packaging footprint came to 97,222 metric tons in 2021.
Oceana estimated that Amazon used nearly 322,000 metric tons of plastic in 2021, more than triple what the company calculated.
By Oceana's count, Amazon used 52% more plastic last year compared with 2019, the first year the group conducted its analysis.
In 2021, Target, Walmart, Coca-Cola, and PepsiCo each used more plastic packaging than the previous year, contributing to an overall 4.3% increase across brands and retailers.
California, the largest economy in the US, passed a law in June to cut plastic packaging in the state by 25% over a decade.