Table 1.

Intracellular boron concentration and the ratio of intra- and extracellular boron concentrations.

Extracellular boron concentration	HSG	MG63	SAS	G-361
20 ppm, mean (range)	73.7 (73.3–73.8)	87.8 (85.2–91.7)	90.9 (80.2–103.7)	85.7 (80.6–91.4)
I/E ratio	3.69	4.39	4.55	4.28
80 ppm, mean (range)	168.7 (166.3–173.0)	230.1 (228.8–231.2)	193.6 (131.9–227.6)	339.0 (295.4–386.9)
I/E ratio	2.11	2.88	2.42	4.24

G-361 human malignant melanoma cell, HSG human salivary gland tumor cell, I/E intra- and extracellular boron concentration, MG63 human osteosarcoma cell, SAS human tongue squamous-cell carcinoma cell.