Table 2.

Comparison of blood ethanol concentrations (g/L) in glass or plastic tubes with fluoride-oxalate preservatives when the tubes were positioned vertically or horizontally at room temperature for two days.

Tube position	Tube material glass (G) or plastic (P)	Ethanol conc. 0.195 g/L	Ethanol conc. 1.016 g/L	Ethanol conc. 2.020 g/L	Ethanol conc. 3.019 g/L
Horizontal (one tube)1	Glass tube	0.191	1.010	2.026	3.029
	Plastic tube	0.190	1.013	2.013	3.017
	G-P Diff	0.0012	−0.0032	0.0132	0.0122
Vertical (two tubes)3	Glass tube	0.191	1.014	2.023	3.027
	Plastic tube	0.192	1.014	2.012	3.029
	G-P Diff	−0.0012	0.0002	0.00112	−0.0022

^aDuplicate determinations on a single tube.

^bNo analytically significant difference.

^cDuplicate determinations on two tubes.