Table 1.

Summary table concluding the main results of the study. The microbial load was very small. Cell and bacterial 16S rRNA gene copy numbers in the LN phase were below the detection limit. Small numbers of bacteria of up to 10⁴ cells per ml were detected in the ice phase formed underneath the lids or accumulated at the bottom

Sampled phase	Cells and gene copies	Cells or gene copies	Effect of					PCR detection*
	Np < 0.5/ N	Np < 0.5/ N	storage time	air conditioning supply	Opening frequency	Institute	Storage phase	Human	Mycoplasma	fungi
LN liquid phase	0/13	0/13	no	no	no	no	no	0/13	0/13	0/13
Ice rim/lid	2/18	8/18	yes	yes	yes	yes	no	0/18	3/18	3/18
debris	1/3	1/3				yes	na	1/3	1/3	1/3

N, number of samples; N_{p < 0.5}, number of samples above the detection limit of the negative control; yes, detected; no, not detected; na, not applicable; *, detected in at least 2 out of 3 replicates