Maleic hydrazide: should the Delaney amendment apply to its use?

Area of Science:

• Environmental toxicology
• Chemical safety
• Food science

Background:

• Maleic hydrazide is a plant growth regulator used in agriculture.
• Concerns exist regarding its potential mutagenicity and carcinogenicity.
• Human exposure occurs through agricultural, manufacturing, and food chain pathways.

Purpose of the Study:

• To review existing data on maleic hydrazide's chemistry, metabolism, toxicology, mutagenicity, and carcinogenicity.
• To identify knowledge gaps regarding human health risks.
• To recommend further research to inform regulatory action.

Main Methods:

• Literature review of maleic hydrazide's toxicological profile.
• Analysis of potential human exposure routes.
• Identification of necessary future studies.

Main Results:

• Maleic hydrazide is a confirmed mutagen and carcinogen in laboratory settings (cell cultures and animals).
• No direct evidence of human carcinogenicity exists despite widespread exposure.
• Significant data gaps remain regarding long-term ingestion effects and human health impacts.

Conclusions:

• Further epidemiological studies are crucial to evaluate human carcinogenicity in exposed populations.
• Long-term animal ingestion studies are required to confirm carcinogenic potential via this route.
• Metabolism and pharmacokinetic investigations are essential for a comprehensive risk assessment and regulatory decision-making.