Organochlorine pesticide residues in tea and their potential risks to consumers in Ethiopia

Abstract

Tea is the most frequently consumed drink in the sphere; next to the water. However, tea can be contaminated by different pesticides particularly those outdated pesticides which have been familiar as one of the main difficulties in Ethiopia and contaminate the food commodities. From a study done in south west of Ethiopia, Dichlorodiphenyltrichloroethane (DDT) and endosulfan were detected in commonly consumed food items. Therefore, the main aim of this study was to analyze the residue of organochlorine pesticides (OCPs) in tea collected from the market and assessing their risks to consumers. 19 different tea samples were randomly collected from supermarkets in Jimma town and Addis Ababa city. In the analytical procedure, QuEChERS (Quick, Easy, Cheap, Rugged, and Safe) method was applied for the extraction of tea samples. The finding of the study revealed that, five OCPs (aldrin, γ-chlordane, DDT, endrin, and dibutylchlorepoxide) were detected at a concentration of 0.1465, 0.167, 0.2044, 0.3067 and 0.4089 mg kg −1 in domestic tea, respectively, while endosulfan sulfate, methoxychlor, and heptachlor epoxide were detected at a concentration of 0.258, 0.458 and 1.427 mg kg-1 in imported tea samples respectively. From the pesticides detected, the mean concentration of DDT (0.292–0.825 mg kg −1 ) is above the Maximum Residue Limits (MRLs) established by China (0.2 mg kg −1 ). The estimated daily intake (EDI) of γ-chlordane and endrin were above the acceptable daily intakes (ADIs), this indicates that there is a health risk for tea consumers. The detection of pesticide residues in tea reveals that there is the widespread use of OCPs in the study area for agricultural purposes or as vector control. Therefore, strict regulation of pesticides during production, importing, sale, and application in the field is important for Ethiopia.

Review of scientific literature on available methods of assessing organochlorine pesticides in the environment

“…This may reduce the applicability of analytical method in some situations. From Table 4 , very high LOD and LOQ (60–720 ng/g and 30–2400 ng/g) were observed from tea [ 269 ], (10–100 ng/mL and 100–10000 ng/mL) [ 69 ], (12–987 ng/g and 40–3290 ng/g) from fruits and vegetables [ 270 ], and (3700–4800 and 12–16000 ng/mL) [ 271 ], (180–780 ng/g and 62–2380 ng/g) [ 272 ] from human milk ( Table 5 ), respectively. Similarly, Serum of a leopard also showed high LOD (800–34000 ng/mL) [ 25 ], (150–12730 ng/mL) [ 273 ], ( Table 5 ).…”

Determination of pesticide residues in rooibos (Aspalathus linearis) teas in South Africa

“…In another similar study in China, specifically on tea marketed in the Tehran market, their results revealed that consumed tea in Iran is free of pesticide residues or has residues that are lower than existing MRLs [4] , [45] . Natural factors such as temperature, rainfall, volatilization, photolysis, ventilation, biodegradation, pH, dew, and growth dilution, as well as the pre-harvest period between the last application and harvesting, can cause pesticide residues in tea bushes to degrade [39] , [32] , [44] , [40] . In South Africa, the demand for organic farming has increased as customers become more health conscious and the role of food in maintaining a healthy lifestyle, which has contributed to the low use of chemicals in agriculture [43] .…”

Detection methods, migration patterns, and health effects of pesticide residues in tea

“…Furthermore, the risk assessment of 42 pesticides in Tieguanyin tea showed that long-term use of Tieguanyin tea does not pose serious health risks (Yao et al, 2022). Siraj et al (2021) investigated OCPs in different brands of tea in the Ethiopian market and their potential risks to consumers. From the detected pesticides, the average concentration of DDT (0.292-0.825 mg/kg) was higher than the MRL established by China (0.2 mg/kg), and the EDI of γ-chlordane and endrin was higher than the ADI, suggesting a potential health risk to consumers from the long-term consumption of tested tea leaves.…”