title: Influence of harvesting method and washing on the presence of pesticide residues in olives and olive oil.
abstract: The influence of the preliminary steps in olive oil production (harvesting and washing) on pesticide residues in olives and olive oil has been investigated. Analyses were performed by GC-MS/MS and revealed that endosulfan sulfate and two herbicides (diuron and terbuthylazine) were the most frequently found residues in olives and olive oil. The harvesting method has a decisive influence on herbicide concentrations found in olives. Thus, 16 and 48% of the olive samples harvested on the ground after falling from the tree presented concentrations higher than the maximum residue limit (MRL) for diuron and terbuthylazine, respectively. In olives harvested directly from the tree, diuron was not found at concentrations higher than MRL and terbuthylazine was found in only 10% of the samples. The washing step performed routinely in olive mills was effective in removing the superficial contamination by herbicides present in olives harvested on the ground. Nevertheless, even after washing, the olive oil obtained from ground olives showed herbicide residue concentrations higher than those obtained from tree olives.
authors.affiliation: Department of Physical and Analytical Chemistry, University of Jaén, Paraje de las Lagunillas S/N, E-23071 Jaen, Spain.
authors.forename: Maria
authors.initials: M
authors.lastname: Guardia Rubio
authors.forename: Antonio
authors.initials: A
authors.lastname: Ruiz Medina
authors.forename: Antonio
authors.initials: A
authors.lastname: Molina Díaz
authors.forename: María José
authors.initials: MJ
authors.lastname: Ayora Cañada
mesh_terms: D000383:Agriculture / Q000379:methods*; D015394:Molecular Structure; D031658:Olea / Q000737:chemistry*; D000069463:Olive Oil; D010573:Pesticide Residues / Q000032:analysis* / Q000737:chemistry*; D010938:Plant Oils / Q000032:analysis* / Q000737:chemistry*; D012987:Soil; D018709:Statistics, Nonparametric; D014197:Trees / Q000737:chemistry; D014867:Water
chemical_list: D000069463:Olive Oil; D010573:Pesticide Residues; D010938:Plant Oils; D012987:Soil; D014867:Water