0141616 



rsenic in the diet of cattle. Weaver (1962) found no significant 

 rsenic in the milk from a cow showing symptoms of arsenic 

 oisoning. Calvert and Smith (1972) found arsenic in cattle milk 

 ncreased from 0.015 to 0.026 ppm only at the highest diet level 

 ed (3.2 mg As/kg body weight). Lesser amounts produced no 

 ncrease in milk arsenic levels. Underwood (1977) has reported 

 ilk arsenic levels of 0.07 to 1.5 ppm in chronically poisoned 

 attle. The literature suggests that while small quantities of 

 rsenic may appear in milk of exposed individuals, it is doubtful 

 hat any significance with respect to arsenic exposure can be 

 ttached to it. 



In conclusion, arsenic concentration of the kidney, liver and 

 ossibly the spleen have been shown to correlate with arsenic 

 ntake. Elevated levels of arsenic in hair, urine and blood have 

 Iso been shown to occur in exposed individuals. Due to individ- 

 al variations, large groups of subjects should be used to 

 etermine the significance of hair and blood arsenic levels. Both 

 lood and urine arsenic levels have been shown to fluctuate 

 uickly in response to arsenic intake. Urine levels are generally 

 bout one order of magnitude greater than those found in blood and 

 re therefore subject to less sampling and analytical error than 

 he lower levels found in blood. It is the opinion of the authors 

 hat exposure to arsenic can be adequately determined through the 

 se of hair and blood samples providing appropriate analytical 

 lethods can be developed for the latter. The additional accuracy 

 rovided by urine analysis would be unlikely to justify the 

 dditional expense of sample collection and urine analysis for an 

 nitial livestock survey but could be very useful for more 

 etailed studies. The utility of milk, may be of questionable 

 alue . 



2.1.2 Livestock arsenic hazard levels 



Background and elevated levels of arsenic have been docu- 

 lented in many studies (Tables 1, 2, 3 and 4). This data base has 

 ieen used to select arsenic hazard levels documented in the 

 r ollowing sections. 



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