Table 1.

Summary of the results reported in Jacob et al. (2011). Animals were exposed to feed supplemented with 0 (control), 7, 23, 69, 229, or 694 ppm melamine and cyanuric acid (co-exposure groups), 1388 ppm melamine, or 1388 ppm of cyanuric acid for seven days. All endpoints analyzed were affected by combined melamine and cyanuric acid, at a dose level greater than 69 ppm (NOAEL).

Endpoint	Observations per dose group
Body Weight	↔ 0, 7, 23, 69 ppm MEL + CYA
	↓ 229, 694 ppm MEL + CYA
	↔ 1388 ppm MEL
	↔ 1388 ppm CYA
Kidney Weight	↔ 0, 7, 23, 69 ppm MEL + CYA
	↑ 229, 694 ppm MEL + CYA
	↔ 1388 ppm MEL
	↔ 1388 ppm CYA
Kidney Crystals	− 0, 7, 23, 69 ppm MEL + CYA
	+ 229, 694 ppm MEL + CYA
	+ 1388 ppm MEL1
	− 1388 ppm CYA
Urinary Bladder Uroliths and Crystals	− 0, 7, 23, 69 ppm MEL + CYA
	+ 229, 694 ppm MEL + CYA
	− 1388 ppm MEL
	− 1388 ppm CYA
Serum creatinine and BUN	↔ 0, 7, 23, 69 ppm MEL + CYA
	↑229, 694 ppm MEL + CYA
	↔ 1388 ppm MEL
	↔ 1388 ppm CYA

Note. Abbreviations: ↔ No change; ↓ Decreased; ↑ Increased (relative to control). − Absent; + Present. MEL + CYA: co-exposure to melamine and cyanuric acid. MEL: exposure to melamine only. CYA: exposure to cyanuric acid only.

¹A very small number of dispersed crystals was observed in 5 of the 12 rats, when the kidneys were examined by wet mount, but not by histopathology (Jacob et al., 2011).