In a hand blender, bell-shaped blad guards cover the blades.
Still, they are more exposed, unlike a stand blender, in which blades sit at the bottom of the jar.
Touching these sharp blades can lead to an injury.
Take care not to get your finger cut by touching these blades when power is on.
The next concern is using plastic shafts in hot liquids can leak chemicals.
While manufacturers use BPA-free plastic, you should not put the stick blender in hot liquids and let the ingredients cool down to around 140F (60C).
Hot liquid ingredients may also cause a risk of splashing.
These concerns are not serious, and using an immersion blender is very safe when used with care.
Always follow user guides for the appliance you own to avoid misuse or personal damage to yourself or damaging the tool.