The Collaborative International Dictionary
carcinogenicity
carcinogenic \car`cin*o*gen"ic\ (k[aum]r`s[i^]n*[-o]*j[e^]n"[i^]k), adj. Causing or tending to cause cancer; as, the carcinogenic action of certain chemicals or of ionizing radiation. -- car`cin*o*gen*ic"i*ty, n.
Wiktionary
carcinogenicity
n. The state or degree of being carcinogenic.