Urine 1-hydroxypyrene glucuronide concentration plotted by maté consumption and tobacco smoke exposure. We divided subjects into four groups by whether they ever consumed maté and whether they were smoke exposed (currently smoked tobacco or had a urine cotinine greater than category 1). Urine 1-OHPG concentration is plotted on the log scale. From left to right, the median for each group is indicated by the horizontal bar and the values are 0.3, 2.0, 2.4, and 3.4, respectively. From left to right, the number of subjects in each group is 28, 57, 17, and 97, respectively.