Properties of antimony and sources in drinking wate

This is a draft position statement for discussion. This does not represent the views of the Committee and should not be cited.

8.               Antimony (Sb, CAS number: 7440-36-0) is a silvery white metal naturally present in the Earth’s crust (Sundar and Chakravarty, 2010). The most common source of antimony in drinking water appears to be dissolution from metal plumbing and fittings (WHO, 2003). Antimony compounds can exist in trivalent (Sb³⁺) and pentavalent (Sb⁵⁺) states, with trivalent antimony being considered more toxic than pentavalent antimony.  In drinking water, pentavalent antimony is the more prevalent form of antimony. However, some evidence suggests that both can coexist and cycle between each other under certain conditions (Health Canada, 2024). For further information on the properties of antimony, see TOX/2024/38 and TOX/2025/04.