. Author manuscript; available in PMC: 2015 Jun 1.

Published in final edited form as: Cancer Epidemiol Biomarkers Prev. 2014 May 16;23(6):1055–1066. doi: 10.1158/1055-9965.EPI-13-0939

Table 4.

Correlations between self-reported water pipe use and time of exposure and changes in biomarkers^a

	COT_Δ₁	COT_Δ₂	NIC_Δ₁	NIC_Δ₂	NNAL_Δ₁	NNAL_Δ₂	2HPMA_Δ₁	3HPMA_Δ₁	AAMA_Δ₁	CNEMA_Δ₁	MHBMA_Δ₁	HEMA_Δ₁	PMA_Δ₁
Time in bar	0.16	0.14	0.05	0.21	0.11	0.04	0.27^*	−0.28^*	0.13	0.05	0.18	0.03	0.07
Smoking duration	0.09	0.15	0.13	0.41^**	0.10	0.05	0.22	−0.10	−0.02	−0.06	0.15	−0.08	0.01
Number of bowls	0.27^*	0.18	0.17	0.11	0.10	0.08	0.05	−0.18	0.21	0.19	0.13	0.10	0.19
Bowls per user	0.35^**	0.28^*	0.10	0.08	0.18	0.14	0.12	−0.15	0.22	0.24	0.00	0.02	0.23
Prior SHS	0.21	0.25	0.02	0.22	0.21	0.26^*	−0.06	0.04	0.20	0.16	0.07	0.20	0.22

All subjects included in the analysis; COT = cotinine; NIC = nicotine; NNAL = 4–(methylnitrosamino)–1–(3–pyridyl)–1–butanol; VOC mercapturic acid metabolites (parent compound in parenthesis): 2HPMA=2-hydroxypropyl (propylene oxide), 3-HPMA=3-hydroxypropyl (acrolein), AAMA=2-carbamoylethyl (acrylamide), CNEMA=cyanoethyl (acrylonitrile), MHBMA=2-hydroxy-3-buten-1-yl or isomer(s) (1,3-butadiene), HEMA=2-hydroxyethyl (ethylene oxide), and PMA=phenyl (benzene);

Δ₁ = post minus pre-exposure; Δ₂ = nextday minus pre-exposure; VOC mercapturic acid metabolites were only measured in pre-exposure and post-exposure samples;

p < 0.05

^**

p < 0.01

*** p < 0.001