Method Validation for Measurement of Hair Nicotine Levels in Adolescents with Congenital Heart Disease (CHD)
Johns Hopkins University
The use of e-cigarettes (i.e., vaping) among adolescents in the United States has recently doubled, as reported by SAMHSA in 2020. Adolescents who have survived congenital heart disease (CHD) are at an elevated risk to the harmful effects of e-cigarettes. When CHD survivors reach 12 years of age, they begin the process of transitioning care from a pediatric to an adult cardiologist which entails them assuming more responsibility for their health care. In the US, 1/3 of those with CHD discontinue cardiology care during the transition period, which is the time where they are exposed by peer pressure to start using e-cigarettes (Jackson et al., 2018). Therefore, there is a need to assess exposure to tobacco for adolescents with CHD in order to develop and implement prevention strategies. Hair nicotine concentration has been increasingly used as a biomarker for tobacco use and second-hand exposure due to the ease of collection and storage. Among chromatographic methods, hair analyses have been commonly performed with liquid chromatography–tandem mass spectrometry (LC–MS/MS) or GC/MS, due to their sensitivity and ability to specifically detect nicotine (Kim et al., 2008). Few studies, however, have examined an isotope dilution method for measuring hair nicotine in GC/MS. The aim of this study was to validate the isotope dilution GC/MS method for measuring nicotine in hair samples obtained from adolescents who have survived congenital heart disease. There are several ways to assess an individual’s exposure to nicotine, including collection of saliva, urine, and hair samples. This study found that GC/MS-based isotope dilution method is a valid approach for determining nicotine in hair samples. The validation process involved assessing linearity, precision, limit of detection, and recovery. Using calibration standards, linearity was strong amongst all batches (R2 > 0.99). The average of the limit of detection was 0.144, which was comparable to previous studies. The precision and recovery values were also within the acceptable range. Additionally, the correlation between primary and duplicate hair sample analyses indicated good reproducibility and consistency. The results contribute to the growing body of evidence supporting the use of hair nicotine as a reliable and non-invasive biomarker for assessing nicotine exposure in research and clinical settings.
Environmental health, risk assessment, nicotine, children, public health, congenital heart disease, CHD, GC/MS, chromatography, hair, analysis