0141636 



2.2.2.2 Toxic cadmium hazard levels for horses 



Data for toxic cadmium concentrations in the tissues of 

 horses were very limited (Table 13). The recommended toxic 

 cadmium hazard level for horse kidneys (75 ppm) is based on the 

 results of Elinder et al . (1981). These authors found a signifi- 

 cant (<0.05) relationship between cadmium concentration and 

 histopathological changes in horse kidney cortex, and noted an 

 increase in the frequency of the histopathological changes at 

 cortex concentrations exceeding 75 ppm. 



The 80 ppm toxic hazard level for horse liver cadmium concen- 

 tration is based on one sample from a horse that died from 

 apparently being "smoked" from smelter emissions (Lewis 1972). To 

 what extent ether metals may have affected this animals is 

 unknown. This hazard level should be used with extreme caution 

 until additional data are obtained. 



The hazard level for toxic concentrations of cadmium in horse 

 hair is also based on the very limited data of Lewis (1972). This 

 author reported a poor correlation between mane hair cadmium 

 concentrations and cadmium concentrations in liver and kidney 

 tissues. The use of this parameter is not recommended until 

 additional support data are obtained. 



2.2.2.3 Toxic cadmium hazard levels for sheeD 



- 



The toxic hazard level reported for cadmium in sheep blood is 

 0.1 to 0.2 ppm (Puis 1981) (Table 14). This range overlaped the 

 background range for this parameter and is not considered diagnos- 

 tic . 



The diagnostic level for toxic concentrations of cadmium in 

 sheep kidney tissue (53 ppm) is based on the study of Wright et 

 al. (1977) who found this level was associated with reproductive 

 failure in sheep. With one exception, all sheep kidney tissue 

 levels in excess of 53 ppm were associated with a degree of 

 toxicity, where as all levels less than 53 ppm, with one excep- 

 tion, were not associated with toxicity. The 53 ppm hazard level 

 agrees well with the 50 to 400 ppm criteria reported by Puis 

 (1981) for toxic concentration of cadmium in sheep kidney tissue. 



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