Registration Dossier

Administrative data

Description of key information

No adequate experimental animal studies are available to evaluate the carcinogenicity of zinc compounds in humans.

Key value for chemical safety assessment

Additional information

Fatty acids, C14 -18 and C16 -18 unsatd., zinc salts:

Data are not available on the carcinogenicity of Fatty acids, C14 -18 and C16 -18 unsatd., zinc salts. Data on other zinc compounds have been used, as it is assumed that during exposure or after intake and absorption Fatty acids, C14 -18 and C16 -18 unsatd., zinc salts are changed (at least in part) to ionic zinc and that only ionic zinc is determining biological activities. A full read-across of data based on the solubility and a molecular weight correction is considered for Fatty acids, C14 -18 and C16 -18 unsatd., zinc salts, see the hazard assessment of "Zinc" within the framework of Regulation (EC) No 1907/2006 below. The following conclusions for zinc compounds apply to Fatty acids, C14 -18 and C16 -18 unsatd., zinc salts.

ZINC:

There are a range of epidemiological studies that investigated the association between zinc exposure either through occupational activities or food supplementation and increased cancer risks. While no associations were found between occupational zinc exposure and excess cancer risk, the main association that has been made in this context is related to dietary/supplemental zinc and prostate cancer risk.

In contrast to established clinical and experimental evidence that prostate cancer is associated with a decrease in the zinc uptake, numerous epidemiology studies and reports of the effect of dietary and supplemental zinc on the incidence of prostated cancer have provided divergent, inconsistent and inconclusive results which range from adverse effects of zinc, protective effects of zinc and no effect of zinc on the risk of prostate cancer. Clinical and experimental studies have established that zinc levels are decreased in prostate cancer and support a role of zinc as a tumor suppressor agent. Malignant prostate cellsin situare incapable of accumulating high zinc levels from circulation (Franklin R.B.et al.,2005; Costello L.C, and Franklin R.B., 2006; Franklin R.B. and Costello L.C,, 2007).

In a recent critical assessment of epidemiology studies regarding dietary/supplemental zinc and prostate cancer risk, Costelloet al.,concluded that epidemiological studies have not provided an established relationship for any effect or lack thereof of dietary/supplemental zinc on the risk of prostate cancer. Proclamations of an association of dietary/supplemental zinc and increased prostate cancer are based on inconclusive and uncorroborated reports (Costello L.C.et al.,2008).

Justification for classification or non-classification

There is no evidence for an intrinsic carcinogenicity of zinc compounds relevant to humans. Therefore classification is not required for carcinogenicity according to CLP Regulation (EC) No 1272/2008 and Directive 67/548 EEC.