Isoprene Exposure in the United States Based on Urinary IPM3: NHANES 2015–2016

Abstract

Isoprene is the 2-methyl analog of 1,3-butadiene and is a possible human carcinogen (IARC Group 2B). We assessed isoprene exposure in the general US population by measuring its urinary metabolite, N-acetyl-S-(4-hydroxy-2-methyl-2-buten-1-yl)-L-cysteine (IPM3) in participants (≥3 year old) from the 2015−2016 National Health and Nutrition Examination Survey. Spot urine samples were analyzed for IPM3 using ultrahigh-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry. Exclusive tobacco smokers were distinguished from non-users using a combination of self-reporting and serum cotinine data. IPM3 was detected in 80.2% of samples. The median IPM3 level was higher for exclusive cigarette smokers (39.8 μg/g creatinine) than for non-users (3.05 μg/g creatinine). Sample weighted regression analysis, controlling for creatinine, sex, age, race, body mass index, and diet, showed that IPM3 was positively and significantly associated with serum cotinine. Smoking 1−10 cigarettes per day (CPD, 0.5 pack) was significantly associated with an IPM3 increase of 596% (p < .0001), and smoking >20 CPD (>1 pack) was significantly associated with an IPM3 increase of 1640% (p < .0001), controlling for confounding variables. Drinking beer/ale at median and 90th percentile levels (compared to zero consumption) was associated (p < 0.05) with 0 and 2.9% increase in IPM3 in non-users, respectively. We conclude that tobacco smoke is a major source of isoprene exposure in the US population. This study provides important public health biomonitoring data on isoprene exposure in the general US population.

Intake and Uptake of Chemicals Upon Use of Various Tobacco/Nicotine Products: Can Users be Differentiated by Single or Combinations of Biomarkers?

“…A possible suitability check can be done by testing the conformity of recently published data, which have not been used for calculating the intake and uptake for chemicals in the 6 consumer groups (mainly because they were not yet available when the relative exposure level system was developed). In total, 17 studies on either one or several of the consumer groups of interest were tested for conformity, 9 studies on the release of chemicals from tobacco/nicotine products (86,(129)(130)(131)(132)(133)(134)(135)(136) and 8 studies on biomarker levels (137)(138)(139)(140)(141)(142)(143)(144). For testing the exposure levels for daily intake, 140 comparisons could be performed, comprising tests for 21 different chemicals and 3 products (26 tests with CCs, 12 with HNB products and 114 with ECs).…”

Comparison of urinary mercapturic acid excretions in users of various tobacco/nicotine products

“…26 Recently, this biomarker was applied in the NHANES study of 2015-2016 with more than 2200 subjects. 80 We observed a clear distinction in IPMA3 excretion between smokers (CC) and all other groups (Figure S2). IPMA3 excretion in smokers (CC) on Day 3 was significantly higher compared with all non-CC groups (Table S3).…”

Serum cotinine cut-points for secondhand smoke exposure assessment in children under 5 years: A systemic review

“…The 51 papers included were published between 1985 and 2020. They included one case-control study [ 13 ], 13 cohort studies [ 14 – 26 ] and 37 [ 27 – 63 ] cross-sectional studies from which, one included a matched case-control substudy [ 53 ]; 26 studies obtained data from different cycles of the National Health and Nutrition Examination Survey (NHANES). When applying the modified Newcastle-Ottawa scale, two cohort studies [ 17 , 19 ] and one cross-sectional study [ 36 ], which used data from the NHANES, were judged to be of high quality, and thirty six studies were judged to be of low quality.…”