Protective effects of green tea on antioxidative biomarkers in chemical laboratory workers

Abstract

Chemical materials are environmental contaminants, are extensively used in laboratories, and may cause various forms of health hazards in laboratory workers. Therefore, this toxicity most likely is a result of the oxidative metabolism of chemical to reactive products. As green tea (GT) possesses antioxidant effects, the objective of this study was to examine any amelioration oxidative stress in chemical laboratory workers drinking one cup (3 g/300 ml water) of freshly prepared tea once daily. Baseline characteristics including age, sex, smoking, fruit consumption, and duration of exposure were recorded via questionnaire to the subjects. Saliva level oxidative stress parameters such as total antioxidant capacity (TAC), glutathione peroxidase (GPx), catalase (CAT), and superoxide dismutase (SOD) were estimated before and after consumption of GT in these workers. Treatment of subjects with GT induced a significant reduction in saliva GPx activity (406.61 ± 22.07 vs. 238.96 ± 16.26 U/l p = 0.001) and induction in TAC (0.46 ± 0.029 μmol/ml vs. 0.56 ± 0.031, p = 0.016). No statistically significant alteration was found for saliva SOD (0.080 ± 0.0019 vs. 0.079 ± 0.0014, p > 0.05) and CAT (20.36 ± 0.69 vs. 19.78 ± 0.71, p > 0.05) after 28 days treatment by GT. These results demonstrate that drinking GT during chemical exposure can reduce several parameters indicative of oxidative stress. In conclusion, using GT as a dietary supplement can be a rational protocol to control source of hazards in chemical laboratory workers.

Salivary and Urinary Total Antioxidant Capacity as Biomarkers of Oxidative Stress in Humans

“…Caffeinated or alcoholic antioxidant beverages increased salivary TAC in 50% and urinary TAC in 40% of the interventions. In particular, green tea (GT) consumption for 4 or 12 weeks increased salivary TAC in laboratory workers and elderly subjects [ 94 , 120 ], whereas it did not affect salivary TAC of Taekwondo (TKD) athletes after training [ 80 ]. Besides, Benzie et al [ 141 ] found a significant correlation between urinary FRAP values and urinary total phenolic concentrations after GT consumption.…”

Green Tea Catechin Metabolites Exert Immunoregulatory Effects on CD4+ T Cell and Natural Killer Cell Activities

“…Green tea is particularly well-known for its multiple beneficial effects. Several epidemiological studies have revealed a negative correlation between green tea consumption and the risk of cancer development. − Green tea catechins are the major bioactive components of green tea that have been reported to exert protective effects against various types of cancer. − However, according to previous reports, intact green tea catechins could not easily be absorbed by the intestines.…”

Urinary Extraction of Oxidative Damage in Carpet Weavers

“…In the similar works, previous studies have shown that chemical laboratory, aluminum industry and pesticides workers personnel had been induced oxidative stress [15]- [17].…”