Validación de un método para la determinación del ácido 3-fenoxibenzoico en orina por QuEChERS, microextracción líquido-líquido dispersiva y cromatografía líquida de alta resolución-arreglo de diodos / Validation of a method for the determination of 3-phenoxybenzoic acid in urine using QuEChERS, microextraction liquid-liquid dispersive and high-performance liquid chromatography-diode array

Los piretroides son insecticidas ampliamente usados no sólo en el ámbito agropecuario y doméstico sino también en salud pública. Una vez absorbidos, son rápidamente metabolizados a compuestos polares eliminados por vía renal. Uno de los metabolitos común a un gran número de piretroides es el ácido 3-fenoxibenzoico (3-PBA) el cual es utilizado como marcador de exposición. Se presenta en este trabajo, la validación de una metodología analítica para la determinación del 3-PBA utilizando QuEChERS acoplado a microextracción líquido-líquido dispersiva con tricloroetileno como disolvente extractivo y cromatografía líquida de alta resolución con detector de foto-arreglo de diodos. La validación se realizó con muestras aisladas de orina de voluntarios adultos de ambos sexos sin exposición conocida y orina sintética. El método resultó lineal en el intervalo 9 μg L-1-79 μg L-1; los límites de detección y cuantificación fueron de 3 μg L-1 y 9 μg L-1, respectivamente. No se observaron señales de interferentes a los tiempos de retención del 3-PBA y del ácido 2-fenoxibenzoico (2-PBA), estándar interno, en las muestras de orina blanco. Las señales cromatográficas en las muestras enriquecidas fueron espectralmente homogéneas. Las precisiones intradiarias (RSDr%) (n= 5) para 9 μg L-1 estuvieron comprendidas entre 9,3%-9,9% y para 27 μg L-1 entre 5,9%-10,6%. Las precisiciones interdiarias (RSDint%) (n=15) para los mismos niveles de concentración fueron de 11,8% y 9,1%, respectivamente. El rango de porcentajes de recuperación para 9 μg L-1 fue de 87%-119% y para 27 μg L-1 de 70%-91%. Se evaluó la estabilidad del analito en la muestra y en el extracto. El analito resultó estable a -20 °C durante 7 días en la muestra y durante 1 día en el extracto. Los valores de incertidumbre relativa e incertidumbre expandida fueron evaluados mediante la ecuación de Horwitz, los resultados obtenidos fueron para el nivel 9 μg L-1 de 33% y 65% y para el nivel 27 μg L-1 de 28% y 55%. La aplicabilidad del método validado fue evaluada con muestras reales de personas sin exposición laboral conocida, quienes declararon haber usado insecticidas piretroides. El método resultó sensible y selectivo.

Pyrethroid insecticides are used not only in the agricultural and domestic environment, but also in public health. Once absorbed, they are rapidly metabolized into polar compounds eliminated by the kidneys. One of the metabolites common to many pyrethroids is 3-phenoxybenzoic acid (3-PBA) which are used to evaluate exposure. We present in this paper the validation of an analytical methodology for the determination of 3-PBA using QuEChERS coupled to dispersive liquid-liquid microextraction with trichloroethylene as an extractive solvent and high-performance liquid chromatography with a photodiode array detector. Validation was carried out with isolated samples of urine from adult volunteers of both sexes without exposure and synthetic urine. The method was linear in the interval 9 μg L-1-79 μg L-1; the limit of detection and quantitation were 3 μg L-1 and 9 μg L-1, respectively. Interfering signals were not observed in the blank urine samples and the chromatographic signals in the enriched samples were spectrally homogeneous. The within-run precision (RSDr%) (n = 5) for 9 μg L-1 were between 9.3%-9.9% and for 27 μg L-1 between 5.9%-10.6%. The between-run precision (RSDint%) (n = 15) for the same concentration levels were 11.8% and 9.1%, respectively. The recovery for 9 μg L-1 ranged from 87%-119% and for 27 μg L-1 from 70%-91 %. The stability of the analyte was evaluated in the sample and in the extract. The analyte in the sample was stable at -20 °C for 7 days and in the extract was stable for 1 day. The values of relative uncertainty and expanded uncertainty obtained by the Horwitz equation were 33% and 65% for 9 μg L-1, and 28% and 55% for 27 μg L-1. The applicability of the validated method was evaluated with real samples of people without known occupational exposure, who declared having used pyrethroid insecticides. The method was sensitive and selective.

The Initial Hyperglycemia in Acute Type II Pyrethroid Poisoning

This retrospective observational case series study was conducted to describe the clinical feature of acute type II pyrethroid poisoning, and to investigate whether hyperglycemia at presentation can predict the outcome in patients with type II pyrethroid poisoning. This study included 104 type II pyrethroid poisoned patients. The complication rate and mortality rate was 26.9% and 2.9% in type II pyrethroid poisoned patients. The most common complication was respiratory failure followed by acidosis and hypotension. In non-diabetic type II pyrethroid poisoned patients, patients with complications showed a higher frequency of hyperglycemia, abnormalities on the initial X ray, depressed mentality, lower PaCO2 and HCO3- levels, and a higher WBC and AST levels at the time of admission compared to patients without complication. Hyperglycemia was an independent factor for predicting complications in non-diabetic patients. Diabetic patients had a significantly higher incidence of complications than non-diabetic patients. However, there was no significant predictive factor for complications in patients with diabetes mellitus probably because of small number of diabetes mellitus. In contrast to the relatively low toxicity of pyrethroids in mammals, type II pyrethroid poisoning is not a mild disease. Hyperglycemia at presentation may be useful to predict the critical complications in non-diabetic patients.

Clinical, biochemical and haemathological effects in Rhamdia quelen exposed to cypermethrin / Efeitos clínicos, bioquímicos e hematológicos em Rhamdia quelen expostos à cipermetrina

The acute intoxication of Cypermethrin in Silver Catfish (Rhamdia quelen) was evaluated. Animals weighing 56.67±4.43g and measuring 18.92±1.16cm were exposed to sublethal concentrations of Cypermethrin for the species in hydrological conditions during 96 hours. A total of 52 fish divided into three groups were used and received the following concentrations of Cypermethrin: 0 (n=12); 1.5 (n=20) and 2.5 (n=20)mg/L. The intoxicated animals suffered behavioral changes such as loss of balance, swimming alteration, dyspnea, upright swimming and sudden spiral swimming movements. As soon as the 96-hour period was over, a blood collection for hematological and biochemical analyses was performed. A complete haemogram test, plasmatic protein test, albumin, alanine transaminase (ALT), aspartate aminotransferase (AST), gamma glutamyltransferase and alkaline phosphatase (ALP) were studied. The values of erythrocytes, hematocrits, haemoglobin, total number of leukocytes, thrombocyte, ALT, AST and ALP changed according to the groups. The results have shown that the environmental contamination by Cypermethrin is toxic to the species...

Avaliou-se a intoxicação aguda da cipermetrina em jundiás (Rhamdia quelen). Jundiás que pesavam 56,67±4.43g e mediam 18,92±1,16cm foram expostos a concentrações subletais de cipermetrina para a espécie em 96 horas, via hídrica, utilizando-se 52 peixes, distribuídos em três grupos, segundo a concentração de cipermetrina: 0 (n = 12); 1,5 (n = 20) e 2,5 (n = 20)mg/L. Os animais intoxicados apresentaram alterações comportamentais, como perda de equilíbrio, dispneia, natação na posição vertical e movimentos bruscos de natação em espiral. Após 96 horas de exposição, foi coletado sangue para análises de hemograma completo, proteína plasmática, albumina, alanina aminotransferase (ALT), aspartato aminotransferase (AST), fosfatase alcalina (ALP) e gamaglutamiltransferase. Os valores de eritrócitos, hematócrito, hemoglobina, número total de leucócitos, número total de plaquetas, ALT, AST e ALP diferiram entre os grupos. Os resultados demonstraram que a contaminação ambiental por cipermetrina é tóxica para a espécie...

Distribution of deltamethrin in acute poisoned rats / 法医学杂志

OBJECTIVE@#To establish an animal model in acute poisoned rat by deltamethrin and an analysis method for determination of deltamethrin by gas chromatography-electron capture detector (GC-ECD) and to study the distribution of deltamethrin in rats in order to provide the references for forensic medicine identification about such cases.@*METHODS@#Rats were administered with deltamethrin of different doses(512 and 1,024 mg/kg) and killed 1.5 h later to be dissected rapidly for tissues (blood, hearts, livers, lungs, kidneys and brains etc.). Samples were dehydrated by anhydrous sodium sulfate and extracted with petroleum ether and acetone (V:V=4:1). The level of deltamethrin was determined by GC-ECD.@*RESULTS@#There was a good separate between deltamethrin and endogenous impurities. The limit of quantification for deltamethrin in blood and liver were 0.1 microg/mL and 0.1 microg/g (S/N> or =10), respectively. The recovery rate of deltamethrin in blood was 91.55%-134.37% and both inter-day and intra-day precisions were less than 5.67%. The distribution of deltamethrin in poisoned rats with 512 mg/kg was as follow: lungs > livers > hearts > kidneys > blood > brains and with 1 024 mg/kg dose was lungs > blood > hearts > kidneys > brains > livers (P<0.05).@*CONCLUSION@#The GC-ECD method is sensitive for determination of deltamethrin. The distribution of deltamethrin in rats has a dose-dependent manner. The study suggests that samples of blood, hearts, livers, lungs, kidneys and brains are suitable for deltamethrin poisoned analysis.