METROLOGICAL ANALYSIS OF NITRATES AND HEAVY METALS IN CARROTS: A COMPARATIVE STUDY OF THE COMPLIANCE OF CARROT SAMPLES FROM DIFFERENT REGIONS WITH STANDARDS (O'Z DST)

This article presents a metrological analysis of nitrate and heavy metal (lead, cadmium, arsenic) content in carrot (Daucus carota L.) samples collected from different geographical regions of Uzbekistan and a comparative assessment of their compliance with the requirements of the national standards (Uz DSt). The relevance of the study is explained by the need to monitor nitrate and heavy metal levels in widely consumed vegetables such as carrots to ensure food safety and protect public health. A total of 60 carrot samples from six different geographical regions (northern, southern, eastern, western, central, and mountainous) were analyzed. Nitrate content was determined by ion chromatography (IC) and molecular absorption spectrophotometry, while heavy metal content was determined by atomic absorption spectrometry (AAS) and inductively coupled plasma mass spectrometry (ICP-MS). Metrological characteristics of the measurement results (accuracy, repeatability, reproducibility, limit of detection) were evaluated. The results were compared with the sanitary-epidemiological norms of the Republic of Uzbekistan and the requirements of Uz DSt 1100:2023. According to the study results, 16.7% of the samples exceeded the maximum permissible levels for nitrates, and 33.3% for heavy metals. The highest nitrate content was found in samples from the southern region (362.4±18.3 mg/kg), while the lowest was found in samples from the mountainous region (128.7±9.6 mg/kg). Among heavy metals, lead and cadmium levels were above the norm in carrots grown near industrial areas.