Content Handbook F

Outline of method

10.1 Hot solution of the sample

The sample is dissolved in boiling water; any insoluble matter is filtered off, dried, and weighed.

10.2 Cold solution of the sample

The sample is dissolved in cold water; any insoluble material is filtered off, dried, and weighed.

10.3 Coarse material insoluble in water

The material is shaken with water for a given time, then the mixture is sieved, and any residue on the sieve is dried and weighed.

10.4 Materials insoluble in aqueous solutions of pesticides

The sample is filtered through a sintered glass crucible, the crucible is dried, weighed and hence the insoluble material content is determined.

Scope

The method is used for the determination of (i) impurities in water-soluble technical pesticides or (ii) insoluble materials in water- oluble formulations which could cause blockage of sieves or jets in spray machinery.