Summary of safety studies conducted with synthetic lycopene

Abstract

Lycopene belongs to the group of natural carotenoids, which are found in many fruits and vegetables, but predominantly in tomatoes and tomato-based products. This manuscript summarizes the safety of synthetic lycopene as a water-dispersible beadlet formulation containing antioxidants and includes acute and subchronic safety studies, reproductive studies, genotoxicity studies, metabolic studies, and exploratory studies on the hepatic uptake of lycopene. Lycopene has a low order of acute toxicity and no significant toxicity has been observed in rats treated with lycopene beadlet formulations in the diet at doses of up to 500 mg/kg bw/day for 14 weeks or 1000 mg/kg bw/day for 4 weeks. No teratogenic effects were noted in a rat two-generation study (1000 ppm in the diet) or in a teratology study in rats with 1000 mg/kg bw/day lycopene as beadlet formulations. Lycopene accumulates in hepatocytes and to a lesser extent in spleen. In short-term studies with synthetic lycopene, as a beadlet formulation, and natural source lycopene, as tomato concentrate, the accumulation of lycopene in the liver and the presence of pigment deposits in the hepatocytes were similar and neither was associated with any histopathological changes. The pigment deposits in hepatocytes are no longer present after approximately 13 weeks of depletion, demonstrating reversibility for this effect. Unformulated pure crystalline lycopene and lycopene as a 10% beadlet formulation are not genotoxic as determined in a comprehensive battery of tests, however, improperly stored, unformulated crystalline lycopene can degrade to mutagenic products if exposed to light and air. Lycopene is commercially available only in formulated forms, containing antioxidants, which prevent the degradation of lycopene and other excipients that provide for water dispersibility. In the animal studies, there is a large margin of safety based on the repeated dose safety and reproductive/teratology studies in rodents. In humans, there is a very long history of use with respect to dietary exposure, and even in the case of very high exposures from dietary sources, there is no indication of any significant adverse effects.