Concentrations of selected heterocyclic aromatic amines among US population aged ≥ 6 years: data from NHANES 2013–2014

Data from National Health and Nutrition Examination Survey for US population aged ≥ 6 years for 2013–2014 were used to analyze data for four heterocyclic aromatic amines (HCAA), namely 2-amino-9H-pyrido[2,3-b]indole (AαC), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhlP), harman, and norharman. Data were analyzed separately for children aged 6–11 years (N = 416), adolescents aged 12–19 years (N = 475), adults aged 20–64 years (N = 1913), and seniors aged ≥ 65 years (N = 458). Adult males had lower concentrations of AαC and harman than adult females (1.44 vs. 2.22 pg/mL for AαC, p < 0.01 and 136.8 vs. 163.2 pg/mL for harman, p = 0.04). Racial/ethnic differences were observed in the adjusted concentrations of HCAAs. For adults, adjusted concentrations of HCAAs were lower for non-Hispanic Asians and Hispanics as compared to non-Hispanic blacks and whites. For example for AαC, the adjusted concentrations for non-Hispanic Asians, Hispanics, non-Hispanic blacks and whites were 1.16, 2.00, 2.37, and 2.16 pg/mL respectively. Adjusted concentrations of AαC were found to be lower among nonsmokers as compared to smokers for adolescents (0.34 vs. 1.32 pg/mL, p < 0.01), adults (0.40 vs. 7.91 pg/mL, p < 0.01), and seniors (0.30 vs. 4.29 pg/mL, p < 0.01). For both harman and norharman, adult nonsmokers had lower adjusted concentrations than smokers (125.7 vs. 177.6 pg/mL, p < 0.01 for harman, 296.1 vs. 421.6 pg/mL, p < 001, for norharman). Exposure to environmental tobacco smoke was found to be associated with higher concentrations of AαC among adolescents (p = 0.01) and adults (p = 0.01) and for harman (p = 0.01) and norharman (p = 0.01) among seniors. In conclusion, concentrations of selected HCAAs can be several fold higher among smokers as compared to nonsmokers and gender as well as race/ethnicity also affect the observed concentrations of HCAA.