Search published articles


Showing 2 results for Tea
Concentration of potentially toxic elements in black tea imported to Iran: a potential risk assessment study
Gholamali Javedan, Hamid Reza Ghaffari, Zoha Heidarinejad, Nahid Zeraei, Somayeh Hoseinvandtabar, Fateme Pourramezani, Mehrdad Ahmadi,
Volume 15, Issue 1 (4-2022)
Abstract
Background and Objective: The aim of this study was to investigate the concentration of potentially toxic elements (arsenic, lead, copper, cadmium and mercury) in black tea imported to southern Iran and to assess the risk of carcinogenic and non-carcinogenic exposure to consumers.
Materials and Methods: For this purpose, 94 samples of black tea from 15 brands imported from India in 2021 were selected. Heavy metals concentrations were measured using an atomic absorption spectrometer (GBC model SAVANTAA). After determining the concentration of heavy metals in black tea samples, health risk assessment was determined using Montocarlo simulation technique.
Results: According to the results, the average concentrations of heavy metals namely arsenic, lead, copper, cadmium and mercury were 0.03±0.02, 0.02±0.16, 15.67±7.69, 0.02±0.01 and 0.006±0.005 mg/kg, respectively. The hazard quotient (HQ) of the heavy metals arsenic, lead, copper, cadmium and mercury were 1.07×10-2, 6.37×10-3, 3.45×10-5, 2.05×10-2 and 7.19×10-4, respectively.
Conclusion: Therefore, according to the findings, it can be concluded that the concentrations of potentially toxic elements (arsenic, lead, copper, mercury and cadmium) in black tea were consistent with the standard level of Iran and World Health Organization. Additionally, the average carcinogenic risk index for arsenic metal was 4.49×10-6, which is much lower than the acceptable level of carcinogenic risk (10-6). Therefore, the concentrations of five potentially toxic elements in the studied black tea did not show any significant risk for consumers.
 

Investigation of aflatoxin status in foreign black tea in Tehran, Iran
Leila Faramarz, Mahdi Davari, Rouhollah Karami Osboo,
Volume 18, Issue 2 (9-2025)
Abstract
Background and Objective: Aflatoxins are among the most important and hazardous fungal secondary metabolites, commonly produced in food and animal feed by certain Aspergillus species. Tea is one of the most widely consumed non-alcoholic beverages worldwide and is regarded as a healthy drink, with approximately two-thirds of the global population consuming it daily, particularly in the morning. This study aimed to monitor the presence of aflatoxins in black tea samples collected from Tehran, and to assess the safety of this commonly consumed beverage in the country.
Materials and Methods: In this study, 31 tea samples from different brands were collected in Tehran in May 2023 and analyzed for aflatoxin contamination using a nanoextraction method, followed by high-performance liquid chromatography (HPLC) equipped with a fluorescence detector.
Results: The limit of detection (LOD) values for aflatoxins G1, G2, B1, and B2 were 0.06, 0.35, 0.06, and 0.35 ng/g, respectively, and the limit of quantification (LOQ) values were 0.2, 1, 0.2, and 1 ng/g, respectively. The LOQ values of the present method are comparable to those reported in recent studies conducted in Spain, Austria, and Iran, which reported LOQs higher than 1 ng/g. According to the results obtained, none of the black tea samples from different brands available in the Tehran market contained detectable levels of the four types of aflatoxins (B1, B2, G1, and G2), even below the globally permissible limits (AFs ≥ 10 µg/kg).
Conclusion: Despite the absence of aflatoxin contamination in tea samples consumed in Tehran, previous studies worldwide suggest that tea can be contaminated with fungi and may support mycotoxin production under favorable temperature and humidity conditions. Therefore, ensuring tea safety requires attention to proper processing, adequate storage conditions, and the prevention of aflatoxin-producing fungal growth during production stages.
 

Page 1 from 1     

© 2026 , Tehran University of Medical Sciences, CC BY-NC 4.0

Designed & Developed by: Yektaweb