Biomarkers of exposure and potential harm in adult smokers of 3-7 mg tar yield (Federal Trade Commission) cigarettes and in adult non-smokers

The paper reports levels of 24-h urine nicotine and five of its major metabolites (expressed as nicotine-equivalents) and blood carboxyhaemoglobin as biomarkers of exposure to particulate- and gas-phase cigarette smoke, respectively, from an exploratory pilot study of adult smokers of 3.0 - 6.9 mg tar delivery (Federal Trade Commission (FTC) method) cigarettes. On multiple occasions over 6 weeks, blood high-sensitivity C-reactive protein (hs-CRP), fibrinogen, HDL- and LDL-cholesterol, and 24-h urine 8-epi-prostaglandin F(2 alpha) (8-epi-PGF(2 alpha)) and 11-dehydrothromboxane B(2) (11-dehydro-TxB(2)) were also evaluated as biomarkers of potential harm. All the biomarkers examined, except for LDL-cholesterol, discriminated with high sensitivity and specificity between adult smokers and non-smokers overall. Except for HDL-cholesterol, all biomarker medians were greater in adult smokers than in non- smokers: urine nicotine-equivalents 64.514 versus < 0.034 nmol mg(-1) creatinine (p < 0.001), carboxyhaemoglobin 4.0 versus 0.4% saturation (p < 0.001), hs-CRP 0.27 versus 0.12 mg dl(-1) (p < 0.05), fibrinogen 292 versus 248 mg dl(-1) (p < 0.001), HDL-cholesterol 46 versus 53 mg dl(-1) (p = 0.003), LDL-cholesterol 119 versus 109 mg dl(-1) (p < 0.18), urine 8-epi-PGF(2 alpha) 1935 versus 1034 pg mg(-1) creatinine (p < 0.001) and urine 11-dehydro-TxB(2) 973 versus 710 pg mg(-1) creatinine (p < 0.001). All the biomarkers of exposure and most of the biomarkers of potential harm showed no time of sampling (by visit week) effect.