Final answer:
Turning plates with agar upside down can cause a spillage hazard due to melted agar, especially when incubated at 35°C, which can lead to contaminant growth and safety risks.
Step-by-step explanation:
When plates containing media (agar) are turned upside down, a potential issue that may arise is spillage hazard. Agar media can melt if incubated at temperatures such as 35°C, which is common for bacterial culture incubation. If the plates are then inverted, the melted agar can leak out of the Petri dish, contaminating the surrounding area and potentially other cultures.
This is particularly problematic in cases where the Petri dishes have been left in a warm incubator, as higher temperatures can exacerbate the melting process, leading to spillage and potential safety risks. Additionally, the agar itself may become a medium for contaminant growth if it comes into contact with non-sterile surfaces. Hence, it is imperative to handle agar plates with great care, ensuring they remain upright and are placed in appropriate temperature conditions to avoid such hazards.