Outside the Safe Operating Space of the Planetary Boundary for Novel Entities

Chemical pollution has the potential to cause severe ecosystem and human health problems at different scales,1 but also to alter vital Earth system processes on which human life depends. “Chemical pollution” was included as one of nine planetary boundaries,2 in response to this understanding. Steffen et al.3 renamed the “chemical pollution” boundary to “novel entities” (NE), defined as “new substances, new forms of existing substances and modified life forms”, including “chemicals and other new types of engineered materials or organisms not previously known to the Earth system as well as naturally occurring elements (for example, heavy metals) mobilized by anthropogenic activities”. Steffen et al.3 argued that the anthropogenic introduction of novel entities to the environment is of concern at the global level when these entities exhibit persistence, mobility across scales with consequent widespread distribution and accumulation in organisms and the environment, and potential negative impacts on vital Earth System processes or subsystems.