Study on stability improvement measures of malathion in different matrices

ABSTRACT

Malathion was unstable in many matrices due to its unique structure and physicochemical properties. This study aimed to investigate the storage stability of malathion in a range of products, including cabbage, tomato, lettuce, potato, carrot, grape, and orange. The research sought to elucidate the contributing factors and strategies to enhance malathion’s stability. Significant reduction of malathion was found over time due to the different storage conditions and the properties of the matrices. The results showed that lower temperature could better store samples. The influence of storage form displayed that homogenised form was more stable than coarse form for cabbage, lettuce, grape and orange. Malathion had the worst stability in potato and carrot. This seemed to be attributed to some special substance in high starch crops that promoted rapid degradation of malathion. When pH was adjusted to 3, the residue in cabbage was basically increased to a stable level. Moreover, methanol and dichloromethane could effectively improve the stability of malathion in cabbage, the mass ratio of sample to dichloromethane of 10:1 was better than that of 25:1. Therefore, the selection of appropriate storage conditions and forms, and the incorporation of exogenous additives could offer practical options to improve malathion stability in various matrices.

HIGHLIGHTS

• The storage stability of malathion and its improvement measures were studied.

• Malathion was most unstable in potato and carrot.

• The homogenised form could be used as a better candidate for storage.

• Adjusting pH to 3 effectively improved the stability of malathion.

• More dichloromethane (10:1) added could increase malathion to a stable level.

KEYWORDS:

• Malathion
• storage stability
• storage form
• exogenous additive

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary data

Supplemental data for this article can be accessed online at https://doi.org/10.1080/03067319.2023.2288645.

Additional information

Funding

This study was funded by the Agricultural Science and Technology Innovation Project of Shandong Academy of Agricultural Sciences [CXGC2023F17]; Application of deep eutectic solvent liquid-phase microextraction technology in pesticide residue analysis of agricultural products [CX22YQ34].