The safety of L-5-MTHF-Ca was evaluated by testing for genotoxicity, subchronic and prenatal developmental toxicity. In in vitro assays L-5-MTHF-Ca was not mutagenic and did not induce other chromosomal events.
Additionally, L-5-MTHF-Ca was not genotoxic in the in vivo micronucleus test nor did it induce DNA damage in rat liver cells. In a subchronic toxicity study, rats administered up to 400 mg/kg bw/day of L-5-MTHF-Ca via oral gavage for 13 weeks had no treatment-related mortalities, and no treatment-related effects were identified on behaviour, body weight, food consumption, ophthalmology, haematology, or organ weights. No treatment-related macroscopic or histopathological findings were observed. Calcium and sodium levels increased with increasing dosage, however the slight increases were within historical control ranges and reversible after the recovery period.
L-5-MTHF-Ca is neither teratogenic nor embryotoxic. Based on the results of the in vitro and in vivo studies, the safe use of L-5-MTHF-Ca as an ingredient in foods is supported. The no observed adverse effect level was the highest dose in the subchronic toxicity study, i.e. 400 mg/kg bw/day for male and female rats.
——Magnafolate® ,the Manufacturers & Supplier of active folate -Jinkang(The No.1 manufacture of L-Methylfolate Calcium in China, and No.2 worldwide, with much more experiences in exporting this material to North America, European, Brazil and etc..)