The Centre for Food Safety will follow up reports that some vegetables in retail outlets contain excessive pesticide residue, adding it is not appropriate to compare results obtained through tests conducted on only part of the vegetable.

In response to media enquiries about reported results of tests for pesticides in vegetables, the Centre for Food Safety said the standards adopted in Hong Kong for the monitoring of pesticide residue in food commodities mainly followed those set by the Codex Alimentarius Commission (Codex).

Application of these standards should follow testing methods recommended by Codex. That means tests should be conducted on the whole edible portion of the vegetable, which is the testing method adopted by the centre in monitoring pesticide residue in vegetables.

It is not appropriate to compare results obtained through tests conducted on only part of the vegetable such as leaves or outer skin of vegetables or fruit such as tomatoes with the Codex's standards, it added.

The centre said many pesticides, such as methamidophos, were soluble in water.

The public should take the following steps when washing vegetables:

* Remove the outer leaves;

* Wash well in clean water several times;

* Immerse vegetables in water for one hour and then rinse; and