Which of the following is considered a high-level disinfectant that would inactivate biological spores?

The designation of a high-level disinfectant capable of inactivating biological spores is crucial for ensuring effective decontamination in various settings, particularly in laboratories dealing with potentially hazardous materials. A 10 percent household bleach in water solution is recognized as a strong oxidizing agent, which is why it is effective in destroying a wide range of pathogens, including bacterial spores.

Bleach, specifically sodium hypochlorite, works by denaturing proteins and inactivating nucleic acids, which is essential in disrupting the cellular integrity of spores, rendering them non-viable. For high-level disinfection, bleach solutions are often used in concentrations of around 10 percent because this increases the solution's effectiveness against spores over lower concentrations, such as 5 percent.

Household bleach solutions typically need to sit on the surface for a certain period of contact time to achieve maximum disinfection effectiveness. The higher concentration not only broadens the spectrum of inactivation but also ensures a more definitive kill of more resistant forms of bacteria and viruses, making it critical in laboratories and healthcare settings.