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Excretion characteristics of urinary 8‐hydroxydeoxyguanosine after dietary exposure to polycyclic aromatic hydrocarbons

Urinary 8‐hydroxydeoxyguanosine (8‐OHdG) is considered a noninvasive marker for oxidative stress and also a marker of carcinogenic potential for compounds such as polycyclic aromatic hydrocarbons (PAHs). Although human studies have investigated urinary 8‐OHdG concentrations in PAH‐exposed workers and the general population, the background level and excretion kinetics of urinary 8‐OHdG in humans remain unclear. Two feeding experiments (consumption of barbecued meat of 15 and 30 g/kg for Experiments 1 and 2, respectively) were conducted to examine the excretion characteristics of urinary 8‐OHdG. All urine voided over 7 days was collected, but only first morning (∼8 A.M.) and last afternoon (∼5 P.M.) samples were analyzed for 8‐OHdG. Mean background urinary 8‐OHdG concentration was 4.76 μg/g creatinine. Statistically significant increases (P < 0.05) in urinary 8‐OHdG concentration were observed on the afternoon of the 3rd and 2nd days after barbecued meat consumption for Experiments 1 and 2, respectively. A pattern of diurnal fluctuation (P < 0.05) in 8‐OHdG excretion rate was evident, in that the excretion of 8‐OHdG was faster during the night than during the day. Additionally, significant (P < 0.05) and strong (r > 0.6) correlations were found between urinary 8‐OHdG measured 2–3 days after exposure to barbecued meat, and 1‐hydroxypyrene (1‐OHP) and 3‐hydroxy‐benzo[a]pyrene (3‐OHBaP) concentrations measured within a half day after such exposure. The current results demonstrate a lag in excretion of urinary 8‐OHdG relative to 1‐OHP and 3‐PHBaP after dietary PAH exposure. These relationships highlight the importance of sampling time when assessing PAH‐related DNA lesions through urinary 8‐OHdG. Environ. Mol. Mutagen. 2010. © 2009 Wiley‐Liss, Inc.