Lab Anim Res.  2011 Mar;27(1):25-28. 10.5625/lar.2011.27.1.25.

Increased Nephrotoxicity after Combined Administration of Melamine and Cyanuric Acid in Rats

• Park D
• Kim TK
• Choi YJ
• Lee SH
• Bae DK
• Yang G
• Yang YH
• Joo SS
• Choi EK
• Ahn B
• Kim JC
• Kim KS
• Kim YB

• KMID: 2391854
• DOI: http://doi.org/10.5625/lar.2011.27.1.25

Abstract

Renal toxicity by melamine in combination with cyanuric acid (1:1) was investigated. Male rats were orally administered melamine plus cyanuric acid (5, 50 or 400 mg/kg each) for 3 days. In contrast to a negligible effect by melamine alone (50 mg/kg, a no-observed-adverse-effect-level: NOAEL), co-administration with cyanuric acid markedly increased the concentrations of blood urea nitrogen and creatinine, as well as kidney weight. A high dose (400 mg/kg) of melamine plus cyanuric acid induced more severe kidney toxicity. The increased blood parameters for kidney toxicity and organ weight lasted longer than 4 days. Combined treatment with melamine and cyanuric acid (50-400 mg/kg each) resulted in many gold-brown crystals and toxic lesions in renal tubules, which were not observed in animals treated with melamine alone (50 mg/kg). These results indicate that only a 3-day exposure to melamine in combination with cyanuric acid causes severe renal damage, even at a NOAEL for melamine found in a 13-week toxicity study. Therefore, it is suggested that the tolerable daily intake or regulatory/management levels of melamine need to be re-considered for cases of co-exposure with cyanuric acid.

Keyword

Melamine; cyanuric acid; nephrotoxicity; renal crystal

MeSH Terms

Animals
Blood Urea Nitrogen
Creatinine
Humans
Kidney
Male
No-Observed-Adverse-Effect Level
Organ Size
Rats
Triazines
Creatinine
Triazines