Pesticide residues in non-primary edible plant parts: Regulatory considerations and dietary risk assessment of guava leaves

Abstract

Rising consumption of non-primary edible plant parts is creating previously underaddressed pesticide residue and dietary exposure concerns. Guava leaves are widely consumed as herbal infusions and incorporated into pharmaceutical and food products. However, intensive pesticide use during cultivation may result in residue accumulation in leaves and derived products, raising potential public health concerns. This study investigated the occurrence and levels of multi-class pesticide residues in eleven dried guava leaf samples (branded and non-branded) and four guava-containing pharmaceutical preparations collected from Egypt. Compliance with European Union Maximum Residue Limits (EU-MRLs) and realistic consumer exposure scenarios were evaluated. Additionally, a leaf sample was traced back to its farm source, where associated environmental matrices (soil and irrigation water) and guava fruit were analyzed to assess pesticide contamination. Detected concentrations ranged from 0.0015 mg/kg (lufenuron) to 1.97 mg/kg (imidacloprid), with 8–27 residues per sample. Environmental samples showed minimal contamination, and the corresponding fruit contained only one residue. Infusion processing factors refined exposure estimates. Dietary risk assessment based on Estimated Daily Intake and risk quotient calculations for adults, children, and infants indicated no appreciable health risk, despite the high frequency of pesticide occurrence.