I am not using hairspray any longer - printafix works better anyway and the bottles are more manageable.

Another safety concern is the use of MEK (methyl ethyl ketone) as a solvent for PLA. People have been using this to smoothen parts and clean out nozzles. Under prolonged exposure this is veritably harmful to the nervous system and it is recommended only to use it with a full body overall + gas mask independent of environment air. It is better to just replace the nozzles, the prices have dropped anyway.