World Wide Fund for Nature (WWF) commissioned Dalberg to estimate the full societal cost of plastic, adding up the market price, greenhouse-gas costs, health costs, waste-management costs and the damage to marine ecosystems over the lifetime of the plastic produced in one year.
They estimated the lifetime cost of plastic produced in 2019 at US$3.7 trillion, more than India's gross domestic product (GDP). Without action, the plastic produced in 2040 would cost US$7.1 trillion over its lifetime. The report argued that these costs fall on governments, communities and future generations rather than the producers who profit.
The report matters because it puts a headline economic figure on plastic's hidden costs, the ones paid by society rather than by the companies that make and sell it, that policymakers and businesses can weigh against the cost of alternatives.
About 85% of the total is the valued damage to marine ecosystems, which relies on contested methods for pricing nature. Treat it as a rough guide to scale, not a precise figure.