Tattoo ink exposure is associated with lymphoma and skin cancers
bmcpublichealth.biomedcentral.com
bmcpublichealth.biomedcentral.com
"Possible association between tattoos and lymphoma" - https://news.ycombinator.com/item?id=40489486
Tattoos are not in the upper skin layer though. Also removing any skin layers is quite dangerous, at least in a statistical sense.
Even the authors agree with awestley:
> Additionally, having a tattoo, especially among adolescents, has been suggested as an indicator of risky lifestyle highly associated with e.g. smoking [4] and alcohol consumption [46] – both risk factors of certain cancer types. Hence, evidence of an association between tattoo ink exposure and occurrence of cancer may be confounded by other health-related lifestyle factors. We intend to exploit the remainder of the information gathered in the survey in the future.
Indeed, it does seem like a big problem that should really be accounted in the initial analysis.
You could also look at tattoo coverage, as in how much of the body is covered in ink? Would a small tattoo on the shoulder have as much risk as a full back tattoo? There are a lot of extra confounders here that could be better explored, but it gets difficult to get a full dataset. However, given their survey data, they should have more analysis options with more time.
The lack of confounder analysis is a bit surprising, but perhaps the paper was long enough already.
Especially given the recent report of issues with some ink being used. I don't remember the specifics.
I doubt this would stop people from getting tattoos, and I know it isn't stopping myself from planning on being fully covered... but it is still interesting.
If you have tattoos its entirely possible you'll actually be more careful in the sun by applying sunscreen.... but you also might be more prone to showing your ink off and therefore exposing a greater area of skin to the sun.
If there is some common ingredient that has been used in tattoo inks recently and we're concerned about that, let me know.... but generally speaking I don't think this is interesting information
Knowing multiple tattoo artists, that's exactly what they observe from their customers : some are very careful about their skin exposure while other are doing the exact opposite.
They are not healthcare professionnal so they don't study skin cancers, but they can easily tell which one is which based on how the tattoo evolve year after year.
This could probably be the easiest factor to check.
Regarding the inks, since there's little to no regulation, even in the EU, and people tend to get tattooed when away from home, it could be much, much trickier.
Seems likely
> The most frequently used tattoo ink is black. Black ink typically contains soot products like carbon black, which is listed as possibly carcinogenic to humans (mainly based on studies of carbon black inhalation and risk of lung cancer) by the International Agency for Research on Cancer (IARC) [13]. Through the incomplete combustion used for carbon black production, polycyclic aromatic hydrocarbons (PAHs) are formed as byproducts. One of the most dangerous of these is benzo[a]pyrene (BaP), which is classified as carcinogenic to humans by the IARC [14].
You really don't want benzo[a]pyrene floating around your system, it's a potent carcinogen that's been firmly established by many studies. Some papers focus on directly on PAHs and tattoos, for example this PLoS One 2014 paper: https://pubmed.ncbi.nlm.nih.gov/24670978/
In reality, all of us live lives that put at greater risk of this and lesser risk of that. The real value of learning that there's perhaps some association with one of our activities and a specific disease or other kind of harm is that we can be watchful of that disease or harm emerging in our own lives and thereby give ourselves more opportunity to respond. Or perhaps we might use it as reason to moderate, or to finally stop doing something we already feel conflicted about.
So this kind of thing is definitely interesting information for some people, but as often for HN, we can expect a lot of comments engaging with it only in extremes of condemnation or refutation.
I think though, I'd phrase your hypothesis as those with tattoos likely have a different risk to reward calculus.
It usually starts in one of the reds, and spreads inch by inch over the course of a few weeks. It gets raised and itches like crazy, and lasts 2-3 days in a small area before spreading. It's a real struggle not to scratch.
Unfortunately 1/4 of my body is essentially one giant tattoo, so it's got plenty of room to spread. The small patches of surrounding un-inked skin are completely unaffected, so I suspect it's definitely the ink.
When the first red tattoo I got REALLY swelled up, the tattoer told me it's rare but he'd seem it before, and some people don't take red well. From what I understand the red ink 20 years ago was formulated differently than now. I'm not entirely convinced it's just that color, because all of mine itch.