Toxicologic evaluation of a novel, highly soluble biotin salt, magnesium biotinate

A novel, highly soluble biotin salt, magnesium biotinate (MgB), was assessed for general and genetic toxicity using several toxicologic tests. This battery of tests included in vitro bacterial reverse mutation test, in vitro mammalian micronucleus assay, and oral acute, 14-day, and 90-day repeat-dose toxicity in Sprague-Dawley (SD) rats. The results of the in vitro studies indicate that MgB is not mutagenic, clastogenic, or aneugenic. The acute oral toxicity study established an LD₅₀ ≥ 5000 mg MgB/kg. In the 14-day oral toxicity study, doses of MgB up to 2500 mg MgB/kg/day produced no clinical signs or mortality. In the 90-day oral toxicity study, administration of 600 mg MgB/kg/day resulted in no clinical signs and was determined to be the no-observed-adverse-effect-level (NOAEL), which equates to 39 g biotin/day for a 70 kg human. Since MgB is composed of 93% biotin, the 600 mg NOAEL equates to approximately 1.3 million times the current recommended daily allowance of 30 μg biotin/day and 3900 times supplement levels of 10 mg biotin/day. Based on the toxicologic profile and lack of findings in various in vitro and in vivo studies, MgB may be considered safe for long-term human use.