Equation 22 (non-radionuclides), equation 23 (radionuclides), and Table 15 present the exposure variables for the surface water/groundwater milk ingestion pathway. The milk ingestion pathway is conducted for the agricultural pathway only.
  (22)
  (23)
Table 15. Surface Water/Groundwater Milk Ingestion Parameters
| 
   
 Parameter  | 
  
   
 Units  | 
  
   
 Agricultural  | 
| 
   
 Non-radionuclide chemical concentration in water = Cwn  | 
  
   
 mg/L  | 
  
   
 Chemical-specific  | 
| 
   
 Radionuclide chemical concentration in water = Cwr  | 
  
   
 pCi/L  | 
  
   
 Chemical-specific  | 
| 
   
 Quantity of water ingested (dairy) = Qw  | 
  
   
 L/day  | 
  
   
 75 (IAEA 1994)  | 
| 
   
 Milk transfer coefficient = Bm  | 
  
   
 day/L  | 
  
   
 Chemical-specific  | 
| 
   
 Ingestion Rate = IRm  | 
  
   
 L/d  | 
  
   
 0.305 (adult) (EPA 1989b) 0.509 (child) (Pao et al. 1982)  | 
| 
   
 Exposure frequency = EF  | 
  
   
 d/year  | 
  
   
 350 (EPA 1989a)  | 
| 
   
 Exposure duration = ED  | 
  
   
 years  | 
  
   
 24 (adult) 6 (child) (EPA 1989a)  | 
| 
   
 Body weight = BW  | 
  
   
 kg  | 
  
   
 70 (adult) 15 (child) (EPA 1991a)  | 
| 
   
 Conversion Factor = CF2  | 
  
   
 days/yr  | 
  
   
 365  | 
| 
   
 Lifetime = LT  | 
  
   
 years  | 
  
   
 70 (EPA 1989a)  | 
| 
   
 Averaging time = AT  | 
  
   
 years  | 
  
   
 LT (carcinogen) ED (noncarcinogen)  |