Physical, chemical, or biological agent or condition in the environment that has the potential to affect development and health of an organism, either in a positive or a negative manner.
Source:
PAC, 2016, 88, 713. 'Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)' on page 749 (https://doi.org/10.1515/pac-2015-1202)