Triazine residues in raw milk and infant formulas from Spanish northwest, by a diphasic dialysis extraction.

Residue levels of herbicides (triazines) were determined in milk by a new and sensitive analytical method. A total of 312 samples were collected (70 infant formulas and 242 raw milk) biweekly during a 24-month period. A method is reported for the analysis of triazine with extraction by diphasic dialysis and determination by gas chromatography with nitrogen-phosphorus detection (CG/NPD) and by liquid chromatography/mass spectrometry (LC/MS) to confirm positive results. Detection limits (LODs) were 0.01 mg/l for terbuthylazine, 0.07 mg/l for simazine and 0.04 mg/l for atrazine by CG/NPD. Optimal extraction was obtained with dichloromethane at 34 °C, and stirring at 200 rpm for 4 h. This extraction method improves recovery by up to 89% for terbuthylazine, 75% for simazine and 116% for atrazine. The frequency of total samples containing triazine residues was 12.50%; considering, separately, raw milk and infant formulas, this percentage was 16.11% and 5.71%, respectively. Finally, because one sample contained triazine levels slightly higher than established MRLs and owing to the known effects of these contaminants on infants health and development, urgent actions are needed for monitoring and controlling of the level of contamination in infant formula which not exceeds tolerable limit recommended by European and Spanish legislation.

Organophosphorus pesticide residues in raw milk and infant formulas from Spanish northwest.

Residue levels of seven organophosphorus pesticides (OPPs), widely used as dairy cattle ectoparasiticides or in crops used for animal feed, were determined in raw milk and infant formulas. A total of 312 samples were collected (70 from infant formulas and 242 from raw milk) biweekly during a 24-month period. Pesticides were extracted by means of a solid phase system into acetone. An extract aliquot of acetone was injected into a gas chromatograph (GC) with a nitrogen-phosphorus detector. Recoveries of pesticides spiked in milk samples were 62.2 - 97.2 %. The frequency of total samples containing detectable levels of OPP residues was 6.73 % in total milk and 8.67 % in raw milk. The highest percentage incidence measured was for dichlorvos (5.78 %), followed by coumaphos (2.06 %), and parathion methyl (0.83 %). The range of positive results was calculated to be between 0.005 and 0.220 mg kg(- 1). No residue was detected in the final product (infant formulas), so any risk to consumer health, especially to children's health, would be limited.

Estudio de la contaminación por plaguicidas organofosforados y triazinas en leche procedente de diversas rutas de recogida / Study of organophosphorus and triazines pesticides contamination in milk from various withdrawal routes

La utilización de plaguicidas en las labores agrícolas y tratamientos ganaderos, parece hoy en día insustituible, pudiendo generar residuos en los alimentos. En este estudio se ha determinado la presencia en leche de plaguicidas que actualmente tienen un amplio uso, organofosforados y triazinas, y valorando la posible contaminación de las rutas de recogida de leche que ha de ser utilizada en una industria de transformación láctea. En total se han recogido 242 muestras procedentes de 15 rutas de recogida de la parte occidental de Asturias y oriental de la provincia de Lugo (Galicia). Para la determinación de estas sustancias se ha utilizado un cromatógrafo de gases con detector de nitrógeno-fósforo. Los porcentajes de aparición de los plaguicidas estudiados fueron: terbutilazina (6,20%), diclorvos (5,78%), simazina (4,96%), atrazina (4,96%), cumafos (2,06%), y metil paration (0,83%). Considerando estos resultados y comparando las diversas rutas de recogida, se detectó mayor presencia de triazinas en Galicia que en Asturias, y respecto a los organofosforados en las rutas pertenecientes a la costa frente a las de interior

The use of pesticides in agricultural labours and cattleman treatments seems today irreplaceable, being able to generate residues in the foods. In this study has been determined the presence in cow milk of pesticides that currently have a wide use, organophosphorous and triazines, and valuing the possible pollution of the routes of milk withdrawal that there has of be used in a milky transformation industry. In total, 242 samples have been collected originating from 15 withdrawal routes of the western part of Asturias and eastern of the province of Lugo (Galicia). For the determination of these substances, a gas chromatograph with a nitrogenphosphorous detector has been used. The percentages of appearance of the pesticides studied were: terbuthylazine (6.20%), dichlorvos (5.78%), simazine (4.96%), atrazine (4.96%), coumaphos (2.06%), and methyl parathion (0.83%). Considering these results and comparing the various withdrawal routes, was detected greater presence of triazines in Galicia than in Asturias and with respect to the organophosphorous in the routes belonging to the coast as compared to those of interior

Puesta a punto del método de extracción por diálisis difásica para el análisis de triazinas en leches maternizadas / Diphasic dialysis extraction method for the analysis of triazines in milk (infant formulas)

Las triazinas son uno de los grupos de herbicidas más frecuentemente utilizados en las labores agrícolas. Habitualmente su extracción se realiza mediante métodos líquidolíquido. El objetivo de este trabajo fue la puesta a punto del método de extracción de la diálisis difásica para análisis de las triazinas en leches maternizadas. Para ello se utilizó un agitador orbital y membranas de diálisis visking 20/32“, llegando a establecerse como condiciones ideales: temperatura, 34 ºC; velocidad de agitación, 200 rpm; disolvente de extracción, iclorometano, y tiempo de extracción, 4 h. La identificación de los herbicidas y la validación del método analítico siguiendo la normativa vigente se realizó utilizando un cromatógrafo de gases con detector de nitrógeno-fósforo. Los tiempos de retención y las recuperaciones obtenidas para cada una de las triazinas fueron: simazina 6,95 min y 75,3 %; atrazina 17,18 min y 116 % y terbutilazina 17,75 min y 88,7 %, res-pectivamente. A partir de los resultados obtenidos se puede concluir que es un buen método de extracción para el análisis de estos posibles contaminantes en leches maternizadas

Triazines are one of the groups of herbicides most frequently used in agricultural labor. Generally, their analyses were carried out with liquid to liquid extraction methods. The aim of this work was to set up diphasic dialysis as an extraction method for the analysis of triazines in milk (infant formulas). An orbital agitator and membranes of dialysis visking 20/32” were used, establishing the following as ideal conditions: temperature, 34 ºC; agitation speed, 200 rpm; extraction solvent, dichloromethane, and extraction time, 4 h. The identification of the herbicides and the validation of the analytical method continuing the outstanding regulation were carried out by using a gas chromatograph with nitrogenphosphorus detector. The retention times and the recoveries obtained for each herbicide from the triazines were: simazine, 16.95 min and 75.30 %; atrazine, 17.18 min and 116.00 % andterbutilazine, 17.75 min and 88.70 %, respectively. According to these results, we can conclude that it is a good extraction method for the analysis of these possible milk pollutants