2Background and purpose: Today, ensuring food security for the inhabitants of the earth, and preserving agricultural production from destruction due to drought, pests, and diseases, seems more necessary than ever. Farmers across the world are forced to use various pesticides to combat factors that reduce production, but these toxins not only remain on the surface of the products but also penetrate the tissues of fruits, vegetables, and even grains. Although washing fruits or peeling them can be effective in reducing surface contamination of pesticides, removing their toxic effects from the internal tissues of fruits is almost impossible. In such a way most agricultural products that have been exposed to pesticides and are presented to the market shortly after spraying contain pesticide residues. Although the use of pesticides and chemical fertilizers in modern agriculture significantly increases agricultural products, it should be noted that excessive use of pesticides in agricultural production leads to higher levels of pesticide residues in agricultural products exceeding the Maximum Residue Limit, which is considered a risk factor for human health and environmental pollution. The negative effects of chemical toxins on health include various types of cancers, neurological diseases, diabetes, respiratory diseases, failures, fetal diseases, genetic problems, and harmful effects on the environment such as pest resistance, their dominance, and the disappearance of beneficial insects. Considering that citrus fruits are considered a strategic product in Mazandaran province, this research was conducted to investigate the level of pesticide residues in citrus orchards in Sari County.
Materials and methods: The residues of pesticides in the citrus fruits produced in Sari county were investigated in areas monitored by the Agricultural Jihad Organization, the Agricultural Research Center, and Natural Resources of Mazandaran province, to control the type, method of pesticide use, and observing the withholding period. In this study, 15 oranges fruit samples were examined. Each sample was approximately 1 kilogram of each product, which was transferred to the food control laboratory of Mazandaran University of Medical Sciences at a temperature of 4 degrees Celsius. The samples were prepared using the QuEChERS method. The consumption and residue levels of pesticides were identified using the GC-MS method. The Food and Drug Organization and the National Standard Organization of Iran (ISIRI) declared 200 types of pesticides as the most commonly used pesticides in citrus orchards, which were evaluated for their residues in this research.
Results: Totally, 3 types of pesticides including Chlorpyrifos, Ethion (Class II), and Pyriproxyfen (Class U) were identified, with Chlorpyrifos being the most commonly used. None of the identified pesticides belonged to Class Ia or Class Ib. Among the identified pesticides, the residue of Ethion exceeded the Maximum Residue Limit (MRL) set by ISIRI.
Conclusion: Given the role of pesticides in food safety and environmental pollution, efforts to reduce the use of pest control poisons to minimize the risk to human health and the environment remain challenging and a valuable goal. Although monitoring of production by executive organizations has led to a significant reduction in pesticide consumption, in some cases, residues higher than the permissible limit are still observed. Also, it should be noted that pesticide residues can become environmental pollutants by entering the soil and water. Therefore, along with increasing farmers' awareness, the expansion, substitution, and implementation of Integrated Pest Management (IPM) are still significant for environmental preservation and cost reduction.