Nicotine intake in cigarette smokers in England: distribution and demographic correlates

Documenting smoke intake by objective biochemical markers is important for quantification of exposure to toxins. The aim of this report is to show the most definitive distribution of the nicotine metabolite, cotinine, yet available from English smokers in the period before implementation of the legislation banning smoking in indoor public areas. A total of 6,423 cigarette smokers, ages 16 years and above, taking part in the Health Survey for England between 1998 and 2003 provided a saliva cotinine value. Data on cigarette consumption, age, gender, social class, deprivation (as indicated by manual or nonmanual occupation, car ownership, and housing tenure), marital status, and region were collected. Cotinine concentrations showed no overall trend over the study period. The mean value was 289.15 ng/mL (SD 174.43); excluding those who had not smoked in the past 24 hours, the mean value was 302.08 ng/mL (SD 168.78). A higher cotinine concentration was associated with being middle-aged (peaking at 40 years), being male, being single, greater economic deprivation, and not living in London. After adjusting for cigarette consumption, higher values were associated with middle age, being male, and greater deprivation. This study provides the most complete picture yet of the smoke intake of cigarette smokers in England. The fact that cotinine peaks at around the age of 40 years raises the possibility that nicotine intake continues to increase decades after a person starts to smoke. Greater nicotine intake in more deprived smokers could explain why they find it harder to stop smoking.