Final answer:
Boiling water at 1 atm achieves disinfection, reducing pathogenic microorganisms to safe levels, but does not achieve sterilization, which is the total elimination of all microbial life.
Step-by-step explanation:
Boiling water at 1 atm (sea level, open system) achieves the level of disinfection. Disinfection is the process of using physical or chemical methods to reduce the number of pathogenic microorganisms on a surface to levels considered safe from a public health standpoint. While boiling can be quite effective at killing vegetative cells and some viruses, it is not effective at killing all microbial forms, particularly endospores, which can survive extended periods of boiling. Therefore, it doesn't achieve sterilization, which is the complete elimination or killing of all forms of microbial life, including bacteria, viruses, fungi, and all biological agents.
For instance, the heat used in boiling is known to alter microbial membranes and denature proteins, leading to the death of many types of microbes. However, endospores from bacteria like Clostridium botulinum demand much higher temperatures to be neutralized, as can be achieved in an autoclave but not in standard boiling practices at 1 atmosphere of pressure.