Pesticide residues in apples grown under a conventional and integrated pest management system

Abstract

This paper describes method validation for determination of more than 40 pesticides in apples using a GC technique. Target compounds belonged to the organochlorine, organophosphorus, carbamates, pyrethroids, triazoles, dicarboximides and strobilurins groups, among others. Sample preparation consisted of acetone extraction and subsequent cleanup/concentration by SPE with a polymer-based sorbent. Single quadrupole GC-MS operating in SIM mode and electron impact ionization was used for identification and quantification of the pesticides. Average recoveries for analytes ranged between 70 and 110% at three fortification levels - 0.01, 0.1 and 0.2 mg kg(-1). Relative standard deviations were lower than 20% for all tested compounds. Calculated limits of detection and limits of quantification were below 0.01 mg kg(-1), which were sufficiently low compared to the maximum residue levels (MRLs) established by European legislation. The proposed method was applied for determination of pesticide residue in four selected apple varieties after harvesting. Whole and processed fruits (peel and peeled fruits) were analyzed from different treatment systems: two conventional, one based on integrated pest management (IPM) and two variants based on organic production (controls). Higher levels of pesticide residues were found in apple fruits under conventional conditions. Fenitrothion and chlorpyrifos residues were detected frequently in apple peel at concentrations up to 0.45 and 0.77 mg kg(-1), respectively. The levels found in the whole fruits of the same samples were much lower than in peel and below the respective MRLs (0.5 mg kg(-1) for both pesticides). Measurable residues of triadimenol only, up to 0.05 mg kg(-1), concentrated in the peel, were found in the apples from IPM.

Comparison of Simple and Rapid Extraction Procedures for the Determination of Pesticide Residues in Fruit Juices by Fast Gas Chromatography–Mass Spectrometry

“…Gas chromatography (GC) coupled to MS with single quadrupole analyzer operating in selected ion monitoring (SIM) has been widely applied for the multiresidue analysis of GCamenable pesticides in different vegetable and fruit matrices (Mezcua et al 2009;Mladenova and Shtereva 2009). The interest on reducing analysis time in multiresidue analysis has increased in the last years, looking for methods designed to determine as many compounds as possible in a short time.…”

Associations between dietary factors and urinary concentrations of organophosphate and pyrethroid metabolites in a Canadian general population

“…Data from the US Department of Agriculture Pesticide Data Program (PDP 1994(PDP -1999 showed that it was 3.2 times more likely to detect pesticide residues in conventional fruits and vegetables than in organic produce (Baker et al, 2002). In addition, pesticide residue levels, including the OP pesticides fenitrothion and chlorpyrifos, were higher in apples grown under conventional conditions than organic production or production using integrated pesticide management (IPM) (Mladenova and Shtereva, 2009). It has been found that children who consumed conventional diets had a median total dimethyl phosphate metabolite concentration six times higher than those consuming organic diets (Curl et al, 2003).…”

Analysis of pesticide residues in strawberries and soils by GC-MS/MS, LC-MS/MS and two-dimensional GC-time-of-flight MS comparing organic and integrated pest management farming

“…Contrary to what most people believe, 'organic' does not automatically mean 'pesticide-free' or 'chemical-free'. Previously, pesticides were found in food samples grown using organic farming (OF) as well as integrated pest management (IPM) prac-tices (Baker et al 2002;Lopes & Simões 2006;Mladenova & Shtereva 2009;Fernandes et al 2011Fernandes et al , 2012aKovacova et al 2013).…”