Issue Flying blind on the Earth-system effects of chemicals and materials

Summary

Humanity produces tens of thousands of chemicals and mixtures at unprecedented speed, yet most have not been tested, or not sufficiently, for their effects on the Earth system. About 95 percent of the roughly 350,000 substances registered worldwide are never measured in the environment, and the structures of a third are unknown or not public. PFASs contaminate surface and groundwater and are expected to persist for centuries to millennia, while PCBs, mostly out of production since the 1980s, still contribute to whale population declines. Harm can take decades to surface, as with acid rain, observed in the mid-1800s but linked to industrial emissions only nearly a century later. Since it is impossible to test every substance before release, the current control variable cannot be applied in practice. The report warns that the greatest risks may lie in effects not yet known and that by the time the danger is fully understood it may be too late to avoid.