Two months after a state-wide ban on Coca Cola and Pepsi was quashed by the Kerala High Court, authorities have filed cases against the soft drink giants alleging that some of their products contain traces of pesticides. The separate petitions filed yesterday in a court here by a food inspector of the state health department said laboratory tests of samples seized from distributors in this city had found that they contained pesticide elements. The case was filed on the basis of tests of samples collected three months ago.