Market basket food samples from six Canadian cities collected from 1992 to 1996 were analysed for pesticide residues. One hundred and thirty-six composites were prepared for each city, representing 99% of the Canadian diet. Residues were found most frequently in peanut butter and butter. DDE, malathion and captan occurred most frequently, while the fungicides chlorothalonil, dicloran and captan were present in the highest concentrations. Processed commodities contained fewer residues and at lower concentrations than the raw products. No residues were detected in either milk or soy-based infant formula. Of the infant foods sampled, fruit contained both the greatest number and highest concentrations of pesticides.