Table 2.
Correlations between biomarkers of cigarette smoke exposure
| Biomarker | Serum Cotinine |
Serum 3HC |
Urine Cotinine |
Urine 3HC |
Urine NNAL |
Nail Nicotine |
Hair Nicotine |
|---|---|---|---|---|---|---|---|
| Serum cotinine | 1 | ||||||
| Serum 3HC | .95 | 1 | |||||
| Urine cotinine | .94 | .91 | 1 | ||||
| Urine 3HC | .91 | .92 | .95 | 1 | |||
| Urine NNAL | .81 | .79 | .84 | .82 | 1 | ||
| Nail nicotine | .72 | .69 | .76 | .74 | .77 | 1 | |
| Hair nicotine | .76 | .74 | .79 | .76 | .69 | .80 | 1 |
3HC, trans-3′-hydroxycotinine; NNAL, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol.
Values shown are Spearman correlations (n = 57–60, p < .0001 for all comparisons). Urine cotinine, 3HC, and NNAL were corrected for urine creatinine (mg).