Thirteen-week oral toxicity study of magnesium chloride in B6C3F1 mice

Abstract Magnesium chloride (MgCl 2 ·6H 2 O) was administered at dietary levels of 0 (control) 0.3, 0.6 1.25 2.5 or 5% to groups of 10 male and 10 female B6C3F 1 mice for 13 weeks. In both sexes of the 5% treatment group a decrease in body weight was observed. While clinical signs and hematological or blood biochemistry parameters showed no treatmentrrelated effects, histopathologically, vacuolation of kidney tubular cells was apparent in males of the 2.5 and 5% concentration groups. Thus, the study demonstrated that diet containing over 2.5% MgCl 2 ·6H 2 O exerts toxic effects in B6C3F 1 mice. We therefore conclude that a 2.5% level of MgCl 2 ·6H 2 O in the diet is the minimal toxic dose.