Assessment of the toxicological profile of Chlorella (C. vulgaris) powder by performing acute and sub-acute oral toxicity studies in mice

Chlorella is a green alga consumed as a dietary food supplement in pulverized form. In addition to its high nutritional value, it is also reported as an excellent detoxifying agent. The Chlorella powder has been reported for removal of mercury, cadmium, and radioactive strontium from the body. The present study evaluated the toxic effect of Chlorella powder (source: Chlorella vulgaris) in Swiss albino mice at acute and sub-acute (28 days repeated dose) doses. In acute and sub-acute oral toxicity studies, mice were administered orally with Chlorella powder at single (2000 mg kg−1) and repeated (1000 mg kg−1, once daily for 28 days) doses, respectively. During the study, mice were observed for clinical signs and mortality, weekly body weight, feed and water consumption, and biochemical, hematological, organ weight, and histological parameters. In the acute oral toxicity study, the test item Chlorella produced no change in clinical signs, and no morbidity or mortality was observed throughout the study period. The change in weekly body weight was statistically insignificant compared to the vehicle control group. In the sub-acute oral toxicity study, no statistically significant changes were observed in behavior, body weight, feed and water consumption, and biochemical, hematological, organ weight, and histological parameters compared to vehicle control mice. No morbidity or mortality was observed during the study period. Oral administration of Chlorella at acute and repeated doses in mice showed no toxicity or adverse effect. The No Observed Adverse Effect Level was estimated to be 1000 mg kg−1 body weight per day for male and female mice.