Transfer of pesticides to the brew during mate drinking process and their relationship with physicochemical properties

Abstract

In order to evaluate the extraction of pesticide residues that are transferred to the brew during mate drinking process of P.U.1 yerba mate leaves (Ilex paraguariensis), a special device to simulate the way in which mate is drunk in Uruguay was developed. The transfer to the brew of 12 organophosphates, 5 synthethic pyrethroids and one organochlorine pesticide from spiked samples was studied. The relationship between the transfer data thus obtained and physicochemical properties like water solubility (Ws), octanol-water coefficient (Kow) and Henry's constant (H) was evaluated. The extractability of the pesticide residues from yerba mate can be correlated with log Ws and log Kow. These transfer values allowed the calculation of ARLs (acceptable residue level) for the pesticides following Food and Agriculture Organization (FAO), World Health Organizaion (WHO) guidelines. These results can help the future establishment of maximum residue levels (MRLs)

Keywords:

• Pesticides
• Mercosur region
• Ilex paraguariensis
• yerba mate
• Kow
• water solubility
• ARLs

Acknowledgments

This work was supported by PEDECIBA Química (Programa de Desarrollo de las Ciencias Básicas), CSIC (Comisión Sectorial de Investigación Cientipica) and Facultad de Química, UdelaR, Uruguay.

This paper was presented at the International Union of Pure and Applied Chemistry (IUPAC) ‘Crop Protection Chemistry’ meeting, held during November 9-12, 2009 at Rio de Janeiro, Brazil.

Dr. Annemieke Farenhorst served as the guest editor for the publication of this paper.