World Health organization  <br/><br/>
Methods used in the user for establishing biologically  safe levels of toxic substances.   

 - 
 - Geneva  W H O  975 
 - 171 p.  26 cm 
 -   .
<br/><br/>  
<br/><br/>  Toxicology 
<br/><br/><label>ISBN: </label>92 4 156043 6 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Toxicology
<br/><br/><label>Dewey Class. No.: </label>QV600  / WHO