title: A subchronic toxicity study of elemental Nano-Se in Sprague-Dawley rats.
abstract: The subchronic toxicity of Nano-Se was compared with selenite and high-selenium protein in rats. Groups of Sprague-Dawley rats (12 males and 12 females per group) were fed diets containing Nano-Se, selenite and high-selenium protein at concentrations of 0, 2, 3, 4 and 5 ppm Se, respectively, for 13 weeks. Clinical observations were made and body weight and food consumption were recorded weekly. At the end of the study, the rats were subjected to a full necropsy, blood samples were collected for hematology and clinical chemistry determination. Histopathological examination was performed on selected tissues. At the two higher doses (4 and 5 ppm Se), significant abnormal changes were found in body weight, hematology, clinical chemistry, relative organ weights and histopathology parameters. However, the toxicity was more pronounced in the selenite and high-selenium protein groups than the Nano-Se group. At the dose of 3 ppm Se, significant growth inhibition and degeneration of liver cells were found in the selenite and high-selenium protein groups. No changes attributable to administration of Nano-Se at the dose of 3 ppm Se were found. Taken together, the no-observed-adverse-effect level (NOAEL) of Nano-Se in male and female rats was considered to be 3 ppm Se, equivalent to 0.22 mg/kg bw/day for males and 0.33 mg/kg bw/day for females. On the other hand, the NOAELs of selenite and high-selenium protein in males and females were considered to be 2 ppm Se, equivalent to 0.14 mg/kg bw/day for males and 0.20 mg/kg bw/day for females. In addition, studies have shown that Nano-Se has a similar bioavailability in rat, and much less acute toxicity in mice compared with selenite. In conclusion, Nano-Se is less toxic than selenite and high-selenium protein in the 13-week rat study.
authors.affiliation: Institute of Nutrition and Food Safety, Chinese Center for Disease Control and Prevention, Beijing, 100050 P.R. China.
authors.forename: X
authors.initials: X
authors.lastname: Jia
authors.forename: N
authors.initials: N
authors.lastname: Li
authors.forename: J
authors.initials: J
authors.lastname: Chen
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000975:Antioxidants / Q000008:administration & dosage / Q000633:toxicity*; D001835:Body Weight / Q000187:drug effects; D004032:Diet; D019587:Dietary Supplements / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D004435:Eating / Q000187:drug effects; D005260:Female; D008099:Liver / Q000187:drug effects / Q000473:pathology; D008297:Male; D019055:No-Observed-Adverse-Effect Level; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D012643:Selenium / Q000008:administration & dosage / Q000633:toxicity*; D018038:Sodium Selenite / Q000633:toxicity; D030262:Soybean Proteins / Q000633:toxicity
chemical_list: D000975:Antioxidants; D030262:Soybean Proteins; D012643:Selenium; D018038:Sodium Selenite