Tattooing is a big business. Although it is difficult to get accurate information the best guess is that last year the tattoo industry grossed $ 1.6 billion dollars. That represents acres of skin that are permanently marked.
Millennials are the the largest group who are tattooed. It is estimated that more than 45% of that group have at least one tattoo, and 15% have 5 or more.
The FDA reports that the inks used by tattoo artists are not approved for injection into the skin. It is possible that the ink used by your local tattoo artist may have been intended for calligraphy or printing and not for tattoos.
In spite of this the rate of complications is low although no government agency tracks this. The absence of federal oversight has left it up to the states to monitor the activity and complication rate of tattoo parlors. Although infections are less likely in licensed parlors fewer than half of the states require certification or licensing of tattooists.
The bottom line is that if you are considering getting a tattoo do your homework. It is better to be safe than it is to be sorry.