Table 3.

Summary of genetic toxicity thresholds in vivo of ENU

Reference	Animals	Tissue	Endpoint	PoD (mg/kg bw/d)
				NOGEL	BMDL
Delft et al	lacZ transgenic mice	Intestine	lacZ gene mutation	10	5.46
			Dlb-1 gene mutation	NTa	1.55
		Spleen	lacZ gene mutation	25	11.7
Bhalli et al	C57BL/6	Peripheral blood	Pig−a gene mutation RET	10	1.46
	mice		Pig−a gene mutation RBC	45	0.95
			Micronucleus RET	10	4.03
O'Brien et al	Muta™ mice	Testis	lacZ gene mutation	2	1
Dobo et al	SD Rat	Peripheral blood	Pig−a gene mutation	0.25	-

Abbreviations: RBC red blood cell, RET reticulocytes, NOGEL no observed genotoxic effect level, BMDL the lower bound of benchmark dose

^aNT: All model failed to fit ( P < 0.1)