Quantification of pesticide residues in milk by HPLC-UV analysis in Gilan province, Iran

Abstract

ABSTRACT Eighty milk samples, comprising raw cow’s milk, pasteurised milk, ultra-high temperature milk, and camel milk, were collected randomly from supply centres from December 2022 to March 2023 in Gilan province, Iran. Aldrin, diazinon, and dichlorodiphenyltrichloroethane (DDT) were determined using high-performance liquid chromatography. Aldrin and diazinon were observed in all samples. Furthermore, 87.5% of the milk samples were contaminated with DDT. The raw milk sample showed the greatest concentration of aldrin, measuring 9.31 ± 0.80 µg L−1, and there was no significant difference with the camel milk. The samples of camel milk, raw milk, and ultra-high temperature milk demonstrated the greatest levels of DDT, whereas the lowest concentration was detected in pasteurised milk. In all samples, the maximum residue level (MRL) of Codex Alimentarius and the national Iran standard (20 µg L−1 for DDT) was only exceeded by 25.1% of the milk samples.