[Urinary cotinine as a marker for passive tobacco smoking]

To provide an objective measure of the hazard smoking parents represent to their children's health, continue concentration in urine was measured by the colorimetric method using barbituric acid (DBA). A total of 205 children, aged 10-12, were examined. The results of laboratory tests were correlated with the data collected by interview. A significant difference in the average value of cotinine concentration was demonstrated between the children whose parents did not smoke (3.2 mumol/L) and those whose one parent smoked (5.8 mumol/L). An even larger concentration was recorded when both parents smoked (7.8 mumol/L). The largest cotinine concentration was determined in the urine of children--passive smokers whose both parents smoked and who did not have a room of their own (9.2 mumol/L). The difference in cotinine concentration between girls and boys was not statistically significant.