A clastogen in biology is a mutagenic agent giving rise to or inducing disruption or breakages of chromosomes, leading to sections of the chromosome being deleted, added, or rearranged. This process is a form of mutagenesis, and can lead to carcinogenesis, as cells that are not killed by the clastogenic effect may become cancerous. Known clastogens include acridine yellow, benzene, ethylene oxide, arsenic, phosphine and mimosine. Exposure to clastogens increases frequency of abnormal germ cells in paternal males, contributing to developmental effects in the fetus upon fertilization.
Illustrative sentence: "This leads to the conclusion that a chemical that fails to induce a significant response in an in vitro clastogenicity assay is unlikely to be clastogenic in vivo, in bone marrow assays."
The term "clastogenic" in volcanic eruptions refers to causing a particular type of ejecta.
Illustrative sentence: "The complex features of this eruption can be explained by rapid deposition of coarse pyroclasts near the vent and the subsequent flowage of clastogenic lavas which were accompanied by a high eruption plume generating pumice falls and/or pyroclastic flows."