Firefly Tattoos (Subdermal tritium lighting implants)

Subdermal tritium lighting implants, or Firefly Tattoos as they are called, use the decay of tritium gas to make glow-in-the-dark implants. Tritium gas decays and emits beta radiation which collides with phosphor and emits photons. Tritium lights are used in watches, gun scopes and emergency exit signs. Standard tritium lights are safe to handle but do emit a small amount of ionizing radiation, which makes them unsafe to implant within the body. By applying a specially designed coating containing a layer of lead oxide glass, we are able to reduce the radiation emitted and make implant safe lights. Firefly Tattoo implants run for many years without the need to be recharged, provide a striking glow in the dark implant, and are small enough to implant using an injection.

(my hand showing the healed implant at night, long exposure was used to get a good picture)

These implants are available now from in colours green and yellow.


How bright are they?
The images in this post should give you some idea of how bright they are, but to give you some examples: In full darkness they are eye catching from across a room. In a dimly lit room they are visible but do not stand out. In a brightly lit room and outdoors during daylight they are not visible at all. This has pros and cons; being invisible in fully lit areas means you can’t show them off as much, but it also means people who work in customer facing roles won’t have to remove or cover them up like they do with piercings and tattoos.

How long will the light last?
Tritium as 12 year half life. This means that after 12 years the implant will be half as bright, after 24 years it will be half as bright again. Obviously given the Firefly Tattoos are new we don’t know exactly how long they will remain visible for, however after 6 years the implant will still retain 75% brightness, which should still be visible.

Will this give me cancer?
It is extremely unlikely, but any exposure to even the smallest amount of radiation increases the odds of getting cancer. We believe that this implant is safe enough that people don’t need to be concerned, but ultimately you need to make your own informed decision.

Will these set off security detectors?
No, since the radiation is being shielded to make the implant safe, it also stops it from being detected. Only an xray would allow someone to see there is an implant, but even then they would not know it is a Firefly Tattoo. However, by examining you in the dark, it would be obvious.

I’m black/Indian/have darker skin, will the lights work for me?
The short answer is we don’t know yet. So far all tests have been done on caucasians, obviously higher melanin levels block more light, so the implants will not work as well in darker skin. They may not be visible at all, or if they are visible, they will be dimmer than in people with pale skin. You are welcome to try anyway, but the result will not be as impressive as in the example pictures. If you do try, please let us know your results.

The long story of how these were developed:

In early 2014 I had an idea. I’d been thinking about implantable LED lights, somewhat similar to the NorthStar (although it didn’t exist at the time), one of the big issues was power, batteries are dangerous, they take lots of room and need recharging often. Then I thought of those cool glow in the dark keychain lights, they use Tritium gas to glow for decades without the need to be charged. I thought it would be really cool to implant one of those lights, my skin would glow indefinitely. I did some reading, and talked to some friends about it, they thought it was a cool idea, but were unsure of the light would be bright enough to be seen through the skin.

I decided to buy a few tritium vials and to do some tests, in true DIY grinder spirit I went to the local supermarket and bought some chicken drumsticks with skin on, I then slid vials under the skin and turned out the lights. The result was very encouraging, the vial was clearly visible through the chicken skin. But I was still not sure how well this experiment would translate to implanting in my own body. After all, chicken skin may be much thinner or more transparent than human skin and the chicken was dead, live skin may block far more light.

picture of the vials in a piece of chicken

(picture of the vials in a piece of chicken)

This lead to only one option: try it. I used one of the RFID needles to implant a vial in my left hand.

(My hand immediately after I implanted a vial)

To begin with I was quite disappointed, the light was barely visible even in total darkness.

(My hand showing the vial in darkness a few hours after being implanted)

I thought about removing it right away, but decided to leave it overnight. The next day was no different, but I decided to keep it implanted for a few days. By day two the swelling was starting to reduce slightly and there was less clotted blood, this meant the light was slightly more noticeable. I began to hope that maybe once it was fully healed, it would be more visible. After a week it was much brighter, still not great, but could be easily seen in darkness, I decided to keep the implant for a few more weeks. At the two week mark it was clearly visible in darkness and noticeable in dimly lit areas as well, I was very happy with the results at this point, it had all been worth it, the blood, sweat and more blood was paying off.

(My hand showing the implant is clearly visible in partial darkness two weeks after implanting)

I knew the vials output a small amount of radiation but thought it was small that I didn’t need to worry about it because I planned to only have the vial implanted for a few days. But now it was looking great and I didn’t want to remove it! So I decided I had better get the vials tested to see if it was safe to keep implanted long term. I sent a vial to Cassox and Glims to have it tested. It was week 4 by the time I got results back, by which time the implant had fully healed, and was even brighter, it was clearly visible across a dark room, was easily visible in dimly lit areas and with a cupped hand to block light could even be seen in fully lit rooms. In short it was everything I had hoped, I was ecstatic! I was the first person in the world with a super cool new implant.

However my joy was sort lived, dosimeter test results showed that the vials were putting out a worrying level of radiation. Not enough to put me in danger from the few weeks I’d had the implant, but high enough that it would be unsafe to leave implanted long term. I removed the implanted vial immediately.

What followed was a long period of research. If the vials were to be safe for long term implantation, I needed to shield the radiation somehow. Radiation shielding is well understood, the most common approach is to place sheet of Lead around the radiation source. However this would not work for me since Lead would also block light, rendering the implant useless.

Eventually I hit on Lead Oxide glass. This type of glass is mostly transparent but contains a high percentage of crystalline lead which means it can block radiation but not light. Lead Oxide glass is definitely not biosafe, so another layer of transparent biosafe coating would be needed. I spent a great deal of time and money trying different configurations of coatings. Eventually I succeeded in encapsulating the tritium vial first in a Lead Oxide glass capsule and an outer capsule of biosafe glass. This increased the size of the implant to 3mm diameter and 20mm long, but was still small enough to be implanted using a needle.

(One of the first safe to implant long term lights I made)

More testing was done, once we were finally satisfied that the implants were safe and effective, we found manufacturers to produce a batch of the implants in yellow and green. We then had them sterilized in needles.

Safety and risks of Tritium

There are two main concerns we need to talk about the safety of tritium, the first is long term exposure to the implant, secondly we need to talk about the risk of the capsule breaking.

(Backgoround radiation in the US. picture from “”

Below are readings from a BlackCat Systems GM-10 dosimeter Cassox used to test the radiation output from a sample implant. You can see the background radiation is quite low at the location of the test, and the implants adds about 1.5 CPM. 1.5 CPM is a tiny increase when compared with the map above, which shows that background radiation can vary more than 40 CPM just based on which area you live in.

(Control image showing background CPM at the time the test was done. Click for larger image if you want to read the numbers)

(CPM results for implant. Click for larger image if you want to read the numbers )

However to be fair, having the added 1.5 CPM inside the body means you won’t get the normal protection the skin provides, therefore a subdermal 1.5 CPM increase is effectively more than a 1.5 CPM increase outside the body. This page explains radiation doses and their risks (, we can see in the tables there, anything less than 100 CPM it not considered dangerous, which makes the 1.5 CPM from the implant insignificant even with long term exposure.

This covers the risk of having the implant for an extended period of time, below we look at the risk of the capsule breaking.

Based on this safety information,, we can see that the time it takes for half of an ingested dose of tritium to be expelled from the body is low, around 12 days. And that by drinking extra water (3-4 liters/day) it can be flushed more quickly from the body.

There are very few reported cases of tritium being ingested, how a couple of cases can be found here ([email protected]+6467). One example is a woman who was exposed to tritium glass, she did not seem to have any long term injury.

If the capsule broke and released the tritium, we recommend seeking medical attention immediately. At the very least the implant should be removed and you should drink extra water for about a month to help flush the tritium from your system.

However, having explained the risks if the capsule were to break, it is extremely unlikely that the implant will break. The capsule is made of three layers of glass, outermost is a thick layer of borosilicate glass (aka Pyrex) which is very strong. Then a layer of lead oxide glass which is less strong but also sealed to stop any gas escaping. Innermost is another layer of borosilicate glass to contain the gas. Even if the outer two layers of glass broke the gas would not be released. Borosilicate glass is much stronger than Schott 8625 glass, the type used to coat RFID implants, and there have been no reported cases of RFID implants breaking within the body, so it is very unlikely even the outermost layer of glass would break once implanted.

However if you think even a single layer of glass has broken we recommend removing the implant immediately. If the outermost layer were to break, the lead oxide glass would be exposed to the body, while not an immediate concern like the tritium is, if left in the body long term lead could leach out, which would be a health concern.

The TL;DR version is: we have done everything we can to minimize risks, but there will always be a small chance something goes wrong. Please do your own research and decide for yourself if the risks are acceptable or not.


As mentioned we have two colors available, green and yellow. The obvious question people will ask is “can I get red/blue/pink/white colored implants”. The reason we didn’t make any other colors is because different colored tritium lights vary greatly in brightness. The chart below shows the relative brightness of different colors.

As you can see, green is the brightest color available, followed by yellow. Green can be easily seen through skin, yellow is visible but is less striking. Another reason yellow implants are dimmer is because I was only able to source slightly shorter yellow lights, meaning the area of light will also be a bit less than green implants. Other colors have not been tested as they will likely not be very noticeable. We strongly advise you to get a green implant first as it is the most eye-catching, and only consider getting a yellow implant later if you want to add variety to your display.

There are no plans at this stage to offer other dimmer colors, however if after trying a green implant you are insistent about wanting different dimmer color, talk to me, I can make one off implants for those who really want them.


The implants come in sterilized needles, they can be implanted the same way as  RFID and NFC chips, see this guide for more information. The only thing to consider is that implanting too deeply will make the implant appear dimmer because more light will be blocked by the skin, care should be taken to implant as shallow as possible, while not so close to the surface that the implant will be rejected.

These implants are available on in colours green and yellow.

Thanks for helping make this implant a reality: Cassox (Augmentation Limitless), Glims (Science for the Masses), Chironex (The Thought Emporium).

I have been working on this for a very long time, I’m so glad to finally release it. But it is just one of many projects I’ve been working on, keep your eyes open, I have many more implants in the works.