system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5 - Why do you taste the saline in your mouth when it's put through an IV?
gpt
You know how new tupperware can have that plasticky smell? The IV fluid from prefilled syringes can take on this plasticky smell from the fresh plastic of the syringes.

Smell is basically little bits of material gassing off and floating into the air where you can smell them. So what happens when something smelly gets into your blood? It gasses off into your lungs, and then your lungs have smelly air in them! When you breathe out, you can smell and kind of taste this.

That's how plastic smell can go from the saline syringe material into your mouth during an IV.