Yes, we do. We apply a fungicide only at an early stage (some 4-6 weeks before harvest) in the plant's life during the rainy season. This chemical is widely used in Europe on salad lettuce and has a harvest clearance period of 2 weeks (i.e. we cannot harvest for 2 weeks after application). By this time the active ingredient has broken down.
We also use insecticides that are specific only to caterpillars and another one for leaf miners. Both are totally harmless to humans and are widely used in Integrated Pest Management (IPM) systems in Europe along with introduced natural predators in the glasshouses. Even organic farmers are able to use such insecticides which are derived from plant extracts. Again we strictly follow any recommended harvest clearance periods. Over 95% of salads and vegetables commercially grown in Europe, USA and Australia use pesticides safely in their crop programmes by following strict guidelines.