Which of the following is a common source of laboratory contamination?

Improper disposal of biological waste is a common source of laboratory contamination because it presents a risk of spreading pathogens and hazardous materials. If biological waste, such as used cultures, sharps, or any material that has come into contact with biological samples, is not disposed of correctly, it can contaminate surfaces, equipment, and potentially lead to exposure among personnel. This can compromise sample integrity, lead to inaccurate results, and even pose health risks.

In contrast, using sterile collection containers, regularly cleaning workspaces, and properly storing samples are practices aimed at minimizing contamination risks. These practices help ensure that samples remain uncontaminated throughout the collection, analysis, and storage processes, emphasizing their importance in maintaining a safe and effective laboratory environment.