8.6 Sample processing and storage procedures should be demonstrated to have no significant effect on the residues present in the analytical sample . Where there is evidence that comminution (cutting and homogenisation) at ambient temperature has a significant influence on the degradation of certain pesticide residues , it is recommended that samples are homogenised at low temperature (e.g. frozen and /or in the presence of dry ice). Where comminution is know to affect residues (e.g. dithiocarbamates or fumigants) and practical alternative procedures are not available, the test portion should consist of whole units of the commodity, or segments removed from large units. For all other analyses, the whole laboratory sample need to be comminuted. To improve the extraction efficiency of low moisture containg commodities (e.g. cereals , spices, dried herbs). It is recommended that small p article sizes, preferably less than 1 mm, are obtained. Milling should be performed in a way that avoids extensive heating of the samples , as heating can cause losses of certain pesticide.