Optimization of a Simplified and Effective Analytical Method of Pesticide Residues in Mealworms (Tenebrio molitor Larvae) Combined with GC-MS/MS and LC-MS/MS.

Leesun Kim,Eunsun Kim,Hyun Ho Noh,Kyungae Son,Min-Seok Oh,Danbi Kim,Byeong-Chul Moon,Sujin Baek,Jin-Ho Ro

doi:10.3390/molecules25153518

Abstract

An effective analytical method was optimized for residues including chlorpyrifos–methyl, deltamethrin, fenoxanil, thiobencarb and fludioxonil in mealworms, the larval form of Tenebrio molitor. They are listed for pest control during wheat cultivation and can be found in wheat-bran feed for growing mealworms in South Korea. Analytes were extracted using acetonitrile and salt packet. Four clean-up methods ((1) MgSO4 + 25 mg PSA + 25 mg C18; (2) MgSO4 + 50 mg PSA + 50 mg C18; (3) EMR-lipidTM tube; and (4) 10 mL n-hexane) were investigated and the method (1) was selected due to its robustness. Low-temperature precipitation of fat and proteins improved the recoveries. Recoveries from the Method (1) were satisfying with 70–120% with <20% relative SD at a spiking level of 0.01 mg/kg. With the simultaneous sample preparation, fenoxanil, thiobencarb and fludioxonil were analyzed by liquid chromatography tandem mass spectrometry (LC–MS/MS) and chlorpyrifos–methyl and deltamethrin by gas chromatography tandem mass spectrometry (GC–MS/MS). Quantification limits for LC–MS/MS and GC–MS/MS were 0.5 and 2.5 μg/L, respectively. No pesticides of interest were detected in 30 real samples collected across the nation. However, the data can be provided for establishing maximum residue limits for the pesticides in mealworms in response to the positive list system.

Highlights

As the global population increases, more enhanced and efficient food production is required [1].For example, in disadvantaged social parts or during natural disasters or social conflict times, protein and other nutritional deficiencies are more prevalent
Thiobencarb and fludioxonil are generally recommended for wheat cultivation by Korean National Institute of Agricultural Sciences
A simple and practical method for the determination of pesticide residues in mealworms by GC–MS/MS and LC–MS/MS was described in this study

Summary

Introduction

As the global population increases, more enhanced and efficient food production is required [1].For example, in disadvantaged social parts or during natural disasters or social conflict times, protein and other nutritional deficiencies are more prevalent. The production of beef and pork requires large amount of energy and causes various environmental issues such as groundwater contamination [2]. In this regard, edible insects including beetles, cockroaches, grasshoppers, honeybees, mealworms, silkworms, termites and wasps have drawn attention as alternative protein food sources because insects have great nutritional values (fat, 14.4–33.7%; proteins, 39.3–64.4%) [3] and can offer an environmentally friendly and efficient opportunity to cope with food insecurity among vulnerable people [4]. Some European nations such as the Netherlands and Belgium pay more attention to the promotion and production of insect-derived food, which are sold on their local markets [6]

Methods

Results

Conclusion