Recovery of Synthetic Pyrethroids in Water Samples during Storage and Extraction

Abstract

Monitoring for synthetic pyrethroids in surface water at the sub-parts per billion level requires reproducible sampling and analytical methods. We studied the recovery of bifenthrin, permethrin, and deltamethrin in water during storage in glass containers and extraction using solid-phase membranes. In solid-free water, the concentration of all compounds quickly decreased and then remained constant at 58-72% of the initial concentration, likely due to adsorption to the glass surface. The recovery was enhanced in runoff samples that contained suspended solids, which was attributed to the association of pesticides to the suspended solids. However, the greatest loss occurred when runoff samples were not agitated before extraction, and the loss was largely caused by the exclusion of the suspended solids from the aqueous phase. Nearly 100% extraction recoveries were obtained when C(8) or C(18) membranes were used for extracting runoff samples. Adsorption to glass surfaces and suspended solids can result in substantial underestimation of pyrethroid concentrations or biological activity and therefore should be considered when designing monitoring protocols.

Extraction and Analysis Methods for the Determination of Pyrethroid Insecticides in Surface Water, Sediments and Biological Tissues at Environmentally Relevant Concentrations

“…Surface water commonly differs from DI water in that the former contains certain amounts of suspended solids (Lee et al 2002). Since our facility is within walking distance to the American River, the method was validated using fortified American River water.…”

“…One study shows bifenthrin and permethrin degrade up to 41% within 3 days (Lee 2002). Sediment samples are collected in wide-mouth glass jars and must be frozen if not extracted within 14 days.…”

Otimização e validação da técnica de extração líquido-líquido com partição em baixa temperatura (ELL-PBT) para piretróides em água e análise por CG

“…Dentre elas destacam-se a cromatografia gasosa (CG) acoplada a detector seletivo de captura de elétrons (DCE) 1,5,6 ou acoplada ao detector de massas no modo de seleção de íons [7][8][9] e a cromatografia líquida de alta eficiência (CLAE), acoplada a detector ultravioleta (UV) 10 . Atualmente são encontrados inúmeros trabalhos de monitoramento de resíduos de piretróides em águas 4,11,12 , solos [13][14][15] e alimentos 10,16,17 utilizando as mais diversas técnicas de extração e análise.…”

“…Dentre elas destacam-se a cromatografia gasosa (CG) acoplada a detector seletivo de captura de elétrons (DCE) 1,5,6 ou acoplada ao detector de massas no modo de seleção de íons 7-9 e a cromatografia líquida de alta eficiência (CLAE), acoplada a detector ultravioleta (UV) 10 . Atualmente são encontrados inúmeros trabalhos de monitoramento de resíduos de piretróides em águas 4,11,12 , solos [13][14][15] e alimentos 10,16,17 utilizando as mais diversas técnicas de extração e análise.Nos últimos anos, foram desenvolvidas técnicas de extração e purificação de resíduos de piretróides, com uma demanda menor de solventes, como a extração em fase sólida 11-13 e a microextração em fase sólida 4,18 . Apesar do desenvolvimento das técnicas de extração e microextração em fase sólida, a extração líquido-líquido continua sendo a mais empregada por ser uma técnica simples, que não exige instrumentação sofisticada, e de fácil execução.…”

Immunotoxicity of pyrethroid metabolites in an in vitro model

“…Synthetic pyrethroids (SPs), recognized as two different types by the absence (type I) or presence (type II) of an acyano group, are among the most commonly used insecticides [6]. The popularity of SPs is attributed to their high efficacy to insects, low environmental mobility, and relatively low mammalian and avian toxicity [7].…”