Determination of Multiple Pesticide Residues and Dietary Intake Risk Assessment of 35 Pesticides in Beet from Five Provinces of Northern China

Abstract

A comprehensive analytical method was developed for detecting the presence of 15 organophosphorus pesticide residues in various sugar beet types. This method employed a gas chromatography-flame photometric detector. Additionally, a modified quick, easy, cheap, effective, rugged, safe method, combined with gas chromatography-electron capture detection, was utilized for determining 20 organochlorine pesticide residues. The established procedure was subsequently applied to evaluate and conduct a risk assessment of 208 samples sourced from the principal sugar beet production areas. For sample extraction, acetonitrile was used as the solvent, leading to a phase separation. The supernatant was then extracted and concentrated using rotary evaporation, retaining 10 mL of the extract. This extract was further diluted with acetone and directly injected through a 0.22-µm filter membrane. Gas chromatographic analysis was carried out using programmed temperature mode and FPD detector. The results showed that the 15 pesticides showed good linearity (R² > 0.99) with the limits of detection ranging from 0.0047 to 0.0261 mg/kg, the limits of quantification ranging from 0.0143 to 0.0790 mg/kg, and the average recoveries ranged from 60.3 to 120% with the relative standard deviations of 2.0–19.3%. The risk assessment of 15 organophosphorus, 20 organochlorine, and pyrethroid pesticides was carried out on 208 actual samples, and none of the detected pesticides with reference values exceeded the standard, and the risk quotient of chronic dietary intake was less than 100%, which indicated that the risk of pesticide hazards to human health in sugar beets was low. The method is suitable for the determination of organophosphorus pesticide residues in sugar beets because of its simple operation, high precision and accuracy, short analysis time, and low use of organic solvents.