Martin Wagner/EyeEm/Getty Images

Production of trifluoromethane (HFC-23) and sulfur hexafluoride (SF6) increased at some Russian factories after a carbon-credit scheme was introduced.

Factories in Russia increased their production of industrial waste products and then claimed millions of carbon credits for destroying them after an international trading scheme went into effect.

Evidence published1 in Nature Climate Change reveals that several Russian chemical plants increased production of highly potent greenhouse-gas waste to “unprecedented levels” after they could reap financial benefits from their disposal.

Carbon credits grant nations the right to emit gases that contribute to global warming. They are traded internationally on carbon markets such as the European Union's Emissions Trading Scheme, and their monetary value is determined by how much buyers are willing to pay for them.