Table 6.

Accumulation of trace metals on MCE membranes exposed to conventional cigarette smoke.

	Estimated smoke contents (μg/cig)*	Reported contents in smoke (μg/cig)	References for reported contents in previous column	Tobacco (μg/cig)@	Estimated percent (%) transfer to mainstream smoke
Al	8	0.342 and 0.22	Stohs et al., 1997; Kazi et al., 2009	240	4
As	0.06	0.0041 and 0.012–0.022	Schneider and Krivan, 1993; Stohs et al., 1997	BDL	–
Cd	0.08	0.065, 1.05, 0.016, and 0.007–0.35	Schneider and Krivan, 1993; Stohs et al., 1997; Kazi et al., 2009; Mohammad, 2014	0.26	31
Cu	0.05	0.013, 0.018 and 0.19	Schneider and Krivan, 1993; Stohs et al., 1997; Mohammad, 2014	4.29	1
Fe	0	0.0168 and 0.42	Schneider and Krivan, 1993; Stohs et al., 1997	243	<0.1
Mn	2	0.0026 and 0.003	Mohammad, 2014; Saffari et al., 2014	72	3
Ni	?	0.00146, 0.632 and 0.0–0.51	Schneider and Krivan, 1993; Stohs et al., 1997; Kazi et al., 2009	1	?
Pb	0.01	0.032, 0.289, 0.094 and 0.017–0.98	Schneider and Krivan, 1993; Stohs et al., 1997; Kazi et al., 2009; Mohammad, 2014	0.53	3
Zn	1	0.127, 0.322 and 0.12 –1.21	Schneider and Krivan, 1993; Stohs et al., 1997; Mohammad, 2014	12	12

^*Value determined (for 15 puffs on a cigarette) after accounting for the trace metals on control MCE membranes and for a 6% recovery (of the smoking system).

^@Values from Table 3.

MCE, mixed cellulose ester. ?, Not conclusive since five of eight values from Table 4 are above detection limit. BDL, below detection limit.