Final answer:
Severe skin burns in molecular biology labs described in the video were due to exposure to ultraviolet radiation; following proper safety guidelines and the use of personal protective equipment can prevent such incidents.
Step-by-step explanation:
In the video "Practicing Safe Science", the severe skin burns described that occurred in molecular biology labs were all due to exposure to ultraviolet radiation. Ultraviolet radiation is a form of non-ionizing radiation that can cause direct damage to DNA and skin cells leading to burns. When working in a molecular biology lab, it is extremely important to follow safety guidelines to avoid such risks. This includes the proper use of personal protective equipment (PPE) such as lab coats, gloves, and UV face shields or goggles. Limiting exposure time and ensuring that UV sources, like transilluminators, are properly shielded can also help prevent accidental UV exposure and subsequent skin burns.