For example, some anesthetics, such as quinaldine, MS-222, 2-
phenoxyethanol and benzocaine are limited in their use because of
concerns about their health effects on humans or fish (Lewis et al.,
1985; Clark, 1990; Brown, 1992). In contrast, clove oil (derived from
the plant Eugenia caryophyllata) is generally believed to have few
health concerns and is used in many countries as a topical anesthetic