TABLE 2.--Insecticide present in blood of cattle treated with several systemics. 
Peak level in blood 
Hours after 
treatment DePeils 
Method 
of 
treatment 
Insecticide 
(mg./ke. ) 
Reference 
Ronnel: 
100 Oral 8 ab PAL 
100 do. 12 Bleak 24 
100 do. 8 ake all 
Co-Ral: 
40 Dermal 120 SOLD 14 
37-52 do. - <s5035 AD 
20 Oral 12 S02 se) 
Dimethoate: 
9,10 Oral 2 WD 4 
10 do. 3-6 1-2.3 ifs} 
10 Intramuscular al 4.9 13 
Ruelene: 
el Intramuscular 2 2) ce 
40 Dermal 4 eS 6 
TABLE 3.--Insecticide residues in milk of dairy cows treated with systemic insec’s:.cides. 
Insecticide 
(mg./kg. ) 
Reference 
treatment 
Ronnel 
100 Oral 32 aL 
Co-Ral 
40 Dermal 06 14 
Dimethoate 
9 Oral mee 4 
40 do. 4 4 
Information on the excretion of several organophosphorus insecticides is sum- 
marized in table 4, The data indicate thatthe urine is usually the major route of elimina- 
tion. Only water-soluble compounds can be excreted by this route and most of these 
insecticides are not sufficiently soluble to be excreted directly. Most of the radioactivity 
present in urine samples represents detoxication products of the insecticides, From 
studies of the breakdown products present in the urine has come much basic information 
on the metabolism of insecticides, which will be discussed in more detail with the 
individual chemicals. 
Excretion in the feces is usually less important, although with some compounds 
administered orally it may represent a considerable fraction of the total, The radio- 
activity in the feces may be in the form of both insecticide and detoxication products, 
Occasionally enough insecticide is excreted here to be toxic to feces-breeding flies, 
163 
