Fate of labelled insecticide residues in food products. VI.—Retention of γ‐Benzene Hexachloride by Wheat and Cheese

Abstract

AbstractThe γ‐isomer of benzene hexachloride labelled with 14C has been used to study the rate of loss of the insecticide from whole wheat and its distribution between the flour and bran fractions after milling. Loss from exposed wheat was rapid, but when it was stored in closed containers no loss was detected. After milling the wheat, 40–50% of the initial residue was still present in the ‘fine’ flour fraction while the residue in the bran was increased between two‐ and four‐fold. Loss of the insecticide from Cheddar and Stilton cheeses was slow, about 40% of the weight applied remaining after 44 weeks. Penetration of the insecticide into both types of cheese was slow although appreciably more rapid in the Stilton cheese. Repeated applications caused a build‐up of the insecticide in the outer few millimetres of the cheeses but had little effect on the amount penetrating more deeply. The toxicological significance of such residues is discussed.