chronic exposure

antonym: acute exposure
synonym: long-term exposure
https://doi.org/10.1351/goldbook.16232
Continued exposures occurring over an extended period of time, or a significant fraction of the test species’ or of the group of individuals’, or of the population’s lifetime.
Source:
PAC, 2007, 79, 1583. (Explanatory dictionary of key terms in toxicology (IUPAC Recommendations 2007)) on page 1595 [Terms] [Paper]