[Residues of dichlorvos (DDVP) in sausages and bacon following placement of Mutox strips in sales rooms of butchers' shops].

The purpose of the present series of experiments was to study the DDVP residues in sausages and bacon resulting from the placement of Mutox strips in the sale-rooms of butchers' shops. After extraction from the samples, Dichlorvos was determined thin-layer chromatographically using cholinesterase inhibition. The results obtained show that neither bacon nor lard should be kept for a prolonged period in a sale-room where Mutox strips are hanging.

[Use of dichlorvos in flour mills].

In the framework of studies on the possible use of dichlorvos (DDVP) in flour mills, the authors investigated the effects of various parameters (such as concentration of the DDVP solution to be used, temperature, location of the samples, different kinds of samples and packages) on the formation of DDVP residues on milling products. It was found that a concentration of 0.6 ml of DDVP-50/m3 and temperatures ranging from 18 degrees to 22 degrees C are particularly suited for insect control.

[Field test for determination of mercury in cereals and cereal products].

By means of the method described, rapid semiquantitative mercury determinations may be performed without energy supply in cereals and cereal products. The mercury ions which are liberated by digestion with concentrated H2SO4 and KMnO4 are determined with the aid of a colorimetric method which is based on the formation of a coloured complex of mercury with di-beta-naphthyl-thiocarbazone. The method permits visual comparison of mercury concentrations ranging from 0.

[Formation of dichlorvos residues on cereal products].

Dichlorvos should be used in mill rooms where milling products are stored. The contamination of foods stored in such rooms strongly depends on the mode of application, the concentration of the agent and the temperature. The authors deal with the extent of contamination under various conditions and with the degradation rate in contaminated flours.