Background Testing for pesticides levels in herbal products is an important aspect in determining product safety. Plants and its extracts are widely used as ingredients in botanical dietary supplements and traditional medicines. The extracts of plants, especially those prepared out of organic solvents are rich in secondary metabolites and pigments and adequate clean-up is required since the extracts completely dissolve in organic solvents. Objective The study aims at reporting a multi-residue analytical method for 126 different pesticides in raw material biomass as well as extracts of plants, which are widely used as ingredients in ayurvedic medicines as well as dietary supplements using LC-MSMS and GC-MSMS with a rugged sample preparation technique for accurate results. Method QuEChERS, GPC, GPC coupled with SPE and LLE coupled with SPE sample preparation methods were compared against each other for suitability to test pesticides in selected herbal raw materials and its alcoholic and aqueous extracts. The standard addition method was used for quantifying the level of pesticides below 10 μg/Kg. Results Single laboratory validation for sample preparation involving GPC and SPE resulted linearity in the range of 2.5–500 ng/mL, average intra-day and inter-day precision of 6.6% RSD, and average recovery (spiked at 10 μg/Kg) of 92% for all analytes tested. The method was repeatable with different analysts and days. Conclusions The sample preparation technique combining GPC and SPE as well as LLE and SPE were the most suitable for the selected herbal alcoholic extracts whereas any of the regular techniques involving LLE, SPE, and QuEChERS were suitable for raw material biomass as well as aqueous extracts. Highlights The method was found to be capable of determining selected pesticides in the selected matrices at 10 μg/Kg concentration. Provision of recycling solvents used in GPC+SPE method was adopted to make the method environmentally friendly.

No abstract