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Background and objectives: Phenethyl isothiocyanate (PEITC), a phytochemical from cruciferous vegetables, is known to modulate detoxification enzymes. Fortification of PEITC into a complete nutrition gel, Nutri-PEITC jelly, has been shown to improve its bioavailability. This work aimed to study the effect of Nutri-PEITC jelly on active smokers' detoxification of tobacco-derived carcinogens.Methods: This pre-post trial was conducted on 30 healthy, male, regular smokers. During the pre-intervention period, they smoked regularly for three days. During the postintervention period, they smoked regularly and consumed Nutri-PEITC jelly for three days (40 mg PEITC/day). The total amounts of N-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol metabolites in 24-hour urine were measured by liquid chromatography-tandem mass spectrometry after deconjugation with β-glucuronidase and normalized to the urinary creatinine level. To ensure the consistency of smoking and the actual consumption of Nutri-PEITC jelly, the levels of urinary cotinine and PEITC were measured by using an enzyme-linked immunosorbent assay and liquid chromatography-tandem mass spectrometry, respectively.Results: After consuming Nutri-PEITC jelly, the level of total urinary NNN metabolites (mainly glucuronide conjugates) was significantly increased by up to 4-fold (p < 0.01). In contrast, the level of total urinary 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol metabolites was not significantly altered (p = 0.325). The urinary cotinine level was similar (p = 0.8832), while the urinary PEITC level was greater than that of the pre-intervention period (p < 0.001). Conclusions:The findings suggest that intake of Nutri-PEITC jelly may increase the detoxification of NNN, a tobacco-specific oral carcinogen, likely by promoting glucuronide conjugation. Future randomized controlled trials are warranted to confirm its poten

Background: Hyperlipidemia can induce the endogenous production of reactive oxygen species (ROS), which may cause carcinogenesis. Cytochrome P450 (CYP)2E1 activity, induced by various factors including polyunsaturated fatty acids, effects the incidence of cancers, whereas NQO1, a flavoprotein, may protect against ROS. Objectives: To investigate the effect of CYP2E1 and NQO1 polymorphism on oxidative stress status in Thais with and without dyslipidemia. Methods: We included 1380 apparently healthy employees of the Electricity Generating Authority of Thailand in this study. We determined their CYP2E1 and NQO1 genotypes and related these to blood lipid profiles, and circulating levels of antioxidant enzymes, malondialdehyde (MDA), and reduced glutathione (GSH). Lifestylerelated factors were determined from questionnaires. Results: All tested genotype frequencies were in Hardy-Weinberg equilibrium. The heterozygous and variant genotype distribution and allele frequency of CYP2E1*5B were less common than CYP2E1*6. Heterozygous NQO1 was the most prevalent form. The frequency of the mutated allele CYP2E1*5B was 0.16, CYP2E1*6 was 0.22, and NQO1*2 was 0.43. Significant differences were observed for blood cholesterol, triglyceride, low-density lipoprotein-cholesterol, and high-density lipoprotein-cholesterol between normolipidemic participants, and those with hypercholesterolemia, hypertriglyceridemia, and combined hyperlipidemia. Participants in the hyperlipidemic subgroup who bore any variant alleles of genes had higher plasma MDA and GSH levels, and superoxide dismutase and glutathione peroxidase activity, but lower catalase activity when compared with normolipidemic participants bearing wild-type alleles. Conclusions: Variations in genetic disposition and dyslipidemia can modify oxidative stress status. Relatively more free radicals may be generated in individuals in subgroups with hyperlipidemia bearing any variant alleles.

The aim of this study was to determine the contamination of lead (Pb), cadmium (Cd) and microplastic (MP)-like particles in bivalves and estimate the exposure of the Thai population to these contaminants due to bivalve consumption. Clams, mussels and cockles were purchased from five wholesale seafood markets located on the upper Gulf of Thailand during the period 2017–2019. Determinations of Cd and Pb in the bivalves were conducted using a graphite furnace atomic absorption spectrometer (GFAAS). Visualization was conducted using a stereomicroscope to investigate the morphology and content of MP-like particles in the bivalve samples. The average Pb contents in clams, mussels and cockles were 112, 64 and 151 µg/kg wet wt., respectively. The average Cd contents were 126, 107 and 457 µg/kg wet wt. for clams, mussels and cockles, respectively. The average number of MP-like particles in bivalve samples varied from not detected to 1.2 items/g wet wt. and not detected to 4.3 items/individual. The exposure to Pb, Cd and MP-like particles due to bivalve consumption varied between 0.005 and 0.29 µg/kg bw/day, 0.017 and 28.9 µg/kg bw/month and 0.015 and 27.5 items/person/day, respectively. There was no potential health risk of exposure to Pb and Cd due to bivalve consumption in any age group. However, a high consumption of cockles with high Cd levels (the worst-case scenario) in children may be of concern.