[Acute toxicity and bioavailability of nano red elemental selenium]

Area of Science:

• Biochemistry
• Toxicology
• Nanotechnology

Context:

• Selenium is an essential trace element with varying chemical forms impacting bioavailability and toxicity.
• Nano red elemental selenium (nanose) represents a novel form with potential therapeutic or nutritional applications.
• Understanding the comparative toxicological profile of nanose versus traditional selenium compounds like sodium selenite is crucial for its safe application.

Purpose:

• To compare the in vitro reaction rate, in vivo biological effects, and acute toxicity of nano red elemental selenium (nanose) against sodium selenite.
• To evaluate the impact of nanose and sodium selenite on selenium levels in blood and liver, and on blood glutathione peroxidase (GSH-Px) activity in mice.
• To determine the median lethal dose (LD50) for nanose and sodium selenite in mice to assess their relative acute toxicity.

Summary:

• In vitro studies indicated nanose reacts with glutathione (GSH) at one-tenth the rate of sodium selenite.
• Mice fed nanose or sodium selenite (50 µg/kg BW for 30 days) showed significant increases in blood and liver selenium concentrations and blood GSH-Px activity.
• Acute toxicity tests revealed nanose has substantially lower toxicity, with an LD50 of 112.98 mg/kg BW compared to 15.72 mg/kg BW for sodium selenite.

Impact:

• Nano red elemental selenium demonstrates a favorable safety profile with significantly reduced acute toxicity compared to sodium selenite.
• This finding supports the potential use of nanose as a safer alternative in nutritional supplements or therapeutic applications.
• Further research into nanose's long-term effects and specific mechanisms of action is warranted.