
Dacthal [ 2,3,5,6-Tetrachlorodimethylphthalate} 
No residues of dacthal were found in milk of dairy cows fed this 
compound. About one per cent of intact dacthal was found in the manure. 
Dacthal monoacid, 2,3,5,6-tetrachloromonomethylterephthalate, was eliminated 
via manure (3.3%) and urine (90.9%). Beef liver slices rapidly produced 
this same metabolite. Incubation of dacthal with rumen contents did not 
decompose dacthal (586, 589). 
After application of dacthal to soil, the monomethyl and free 
dicarboxyl analogs were tentatively identified by gas chromatography (537, 
1314). Under conditions of gas chromatography, the monomethyl derivative 
underwent decarboxylation (1314). 

ven, 
Dacthal 
% ACH, 
C 
C1 Cl 
C1 Cl 
Pon 

123 
