Chromium genotoxicity as influenced by complexation and rate effects

Area of Science:

• Environmental Toxicology
• Inorganic Chemistry
• Molecular Biology

Background:

• Mutagenicity and carcinogenicity conclusions for metal salts are often ambiguous, particularly for highly charged metal ions prone to hydrolysis.
• Chromium salts, including Cr(VI) and Cr(III), present complex toxicological profiles.
• Understanding the role of complexation in modulating metal ion mutagenicity is crucial for risk assessment.

Purpose of the Study:

• To investigate the effect of complexation on the mutagenicity of chromium salts using the rec-assay.
• To determine if chelating agents reduce Cr(VI) mutagenicity or induce Cr(III) mutagenicity.

Main Methods:

• Utilized the rec-assay to assess the mutagenicity of chromium salts.
• Tested the impact of various chelating agents, including EDTA, salicylate (SA), and Tiron, on chromium mutagenicity.
• Evaluated the mutagenicity of chelating agents alone and in combination with chromium.

Main Results:

• Several chelating agents, in a concentration-dependent manner, reduced or eliminated the mutagenicity of Cr(VI) (Cr2O32-).
• Salicylate and citrate rendered Cr(III) slightly mutagenic.
• None of the tested chelating agents or their combinations exhibited mutagenicity.

Conclusions:

• Complexation with specific chelants can effectively mitigate the mutagenicity of Cr(VI) salts.
• Cr(III) can exhibit mild mutagenicity upon complexation with certain agents like salicylate and citrate.
• The rec-assay provides a valuable tool for assessing the genotoxic potential of metal-chelate complexes.