Pilot study of methods to measure saliva cotinine in Alaska Native women during pregnancy

Objectives. To evaluate NicAlert (R) immunoassay test strips and liquid chromatography atmospheric-pressure ionization tandem mass spectrometry (LC/MS/MS) for the measurement of saliva cotinine levels in pregnant Alaska Native women. Study Design. Cross-sectional study. Methods. Pregnant women completed a questionnaire about their tobacco use during pregnancy and that of others in the same household. Saliva samples were collected and tested using LC/MS/ MS and NicAlert (R) immunoassay test strips. Results. Seventy-one women participated; 18 reported using tobacco products during pregnancy. Sixteen women reported smoking within the last 7 days of the interview. Median cotinine concentrations in the women who reported smoking in the last 7 days were 94.5 ng/mL using LC/MS/MS (N=13) and 87.5 ng/mL using NicAlert (R) (N=11). Twenty-two women reported that they did not use tobacco and had no exposure to secondhand smoke. Median cotinine concentrations among those with no reported exposure to secondhand smoke were 0.0605 ng/mL using LC/MS/MS (N=18) and 4.38 ng/mL using NicAlert (R) (N=17). Conclusion. NicAlert (R) strips can be used to quickly distinguish between users and nonusers of tobacco, but they are not adequately sensitive to detect and quantify lower concentrations of cotinine among nonsmokers with secondhand exposure. A more sensitive method such as LC/MS/MS is required for that purpose.