Molten tar is bad stuff. I used to work with a guy that had a tattoo nipple. He’d been burned on the chest with tar. I heard from a guy whose uncle had gotten badly burned by tar. He said they just pumped him full of morphine and turned on the radio at the hospital.
My high school chemistry teacher demonstrated why you never heat a test tube from the bottom. It made an impression. A friend works with a lot of heliax in his radio business. Copper tubes separated by plastic. We had occasion to burn some, to salvage some copper. Point the ends in a safe direction, and throw it in a fire. If it built up a charge of molten plastic, it would spit it quite a ways, and it would stick and continue to burn. Nasty stuff.
One summer I was walking on the side of the road near our house and a truck splashed melted tar onto the back of my knee as it passed me...
It hurt like crazy...