Its a plastic resin, but wouldn’t be surprised if someone thought to mix asbestos with it at some point. If made recently, it won’t contain asbestos but still the dust would be harmful if the dust is breathed.

I found alcohol (IPA) wasn’t a reliable fix for all failing 1st layer issues. I still use it because it seems to slow down the inevitable and it’s quick compared with a trip to the sink.

Hard to tell, most of it looks fairly good except a few spots here and there.

That could be grease on the print bed, maybe time to give it a wash? When PETG goes wrong for me, it’s this 90% of the time.

I use hot water and a little detergent with a lot of rinsing. Use gloves because even clean hands leave oils behind.

With PETG it’s hard to get the first layer right but if it’s good the rest of the print generally goes fine.

Molten PETG is very sticky and if you get a bit stuck to the nozzle it can build up, get worse and suddenly take out a bunch of nearby lines leading to gaps in the layer like this.

To counter this PETG first layer should be:

• Printed very slow e.g. 20mm/s
• At a higher Z offset than PLA, the plastic should flow out the nozzle and fall onto the bed rather than be squished flat.
• High bed temperature 80C / 176F
• Zero or very low fan speed for the first couple of layers

If you can see marks left by the nozzle it’s too low. The lines should have a rounded look.

It could also be wet filament, does it make popping sounds when printing?

A Raspberry Pi 3 Model B

It’s connected to my 3d printer and runs octoprint allowing me to upload print jobs. and control the printer from my home network.
It serves up the Pi camera video stream.
It can also switch the printers light on and off.

No cluster setup.