In risk assessment, I determine what risks are present at the workplace of the developer of analytical methods who performs the work in the laboratory. In order to better assess the risks, I have developed an analytical method to better understand the specifics of the specific work environment. The main risks in the workplace are hazardous and harmful substances. The most important measure to reduce the risk is the use of appropriate personal protective equipment and raising workers awareness of working with hazardous substances. In the experimental work I developed a chromatographic method and used it to analyze different samples of vitamin B₁₂ and vitamin supplements. I monitored absorbance, retention times, and the amount of vitamin B₁₂ contained in the compounds.