Investigation of levels and human health risk of heavy metals in tea samples marketed in Jazan, Saudi Arabia 

Following water, tea is the most widely used beverage. Tea is regarded as a healthful beverage because of its relationship with a decreased risk of stroke, metabolic syndrome, obesity, and events related to cardiovascular disease. Tea contains a variety of trace minerals and elements that are good for human health, but if they are present in high enough amounts, some of them can be hazardous and cause cancer. This work stands out due to its thorough evaluation of heavy metal levels, and conducting a risk assessment for tea consumers in Jazan region southern of Saudi Arabia. The present research examined the content of 6 different heavy metals in 11 samples of black tea gathered from local markets in Jazan, southern Saudi Arabia: cadmium (Cd), lead (Pb), chromium (Cr), zinc (Zn), copper (Cu), iron (Fe), and zinc (Zn).  Flame atomic absorption spectroscopy (FAAS) was employed to detect heavy metals in tea samples. The Target Hazard Quotient (THQ) and combined hazard index (HI) for heavy metals in tea samples were employed for assessing the health risks to tea consumers. The study found that the median content of Cd, Pb, Cr, Zn, Cu, and Fe in the investigated samples is 1.31, 2.33, 16.07, 27.88, 5.52, and 120.4 µg/g, respectively. We compared the concentration of heavy metals in the samples under examination to the World Health Organization's (WHO) maximum allowable levels. The findings demonstrated that the mean levels of Cu, Fe, Pb, Cd, and Zn in tea samples were significantly below the maximum permitted values. Conversely, Cr level in tea samples exceeded the maximum allowable values. THQ mean values were 0.003, 0.05, 0.16, 0.19, 0.69, and 0.8 for Cr, Fe, Zn, Pb, Cu, and Cd, respectively. The THQ values of all metals under investigation were found to be below the permitted limits (less than one). These data show that the individual heavy metals present in the investigated samples do not pose any carcinogenic health concerns. In contrast, the HI value for various heavy metals was determined to be greater than one (1.91) indicating that regular tracking of the levels of heavy metals in black tea samples is required. 

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