Ok ive been hitting my lightbulb vape for a while and its a clear bulb, and i did rinse it out with salt. but theres this ring of hard green stuff around the top next to the metal. its really hard to get out. im wondering if i could get cancer or something from hitting the vape cause of that? My hits have been good, good taste, good high, and no throat problems after aside from dryness that weed does.