Do you paint a lot of miniatures? Many miniature painters lick their brushes (see here). I’ve been guilty of doing this, too, but less so now after thinking it might be dangerous in the long-term.
But, is licking your brush really bad for you?
In this article, I try to clarify if paint brush licking is bad for you, e.g., safe or dangerous. The internet is all over the place on this topic. I searched for evidence and here’s what I learned. Hint: There isn’t much information about acrylic hobby paint safety.
Summary (TL;DR): Is Brush Licking Safe or Not?
Non-toxic miniature paints (by major company brands) may be safe for accidental oral consumption by brush licking. If you lick your brushes to keep a fine point, you should be fine. Read on and see disclaimer below.**
Let’s Define Toxicity
To understand the potential danger of brush licking, we should know the definition of a toxin.
READ MORE: IS SALIVA BAD OR GOOD FOR BRUSHES?
A toxin is any chemical that alters the normal function of an organism. In our case, what we want to know is if licking our brushes with some paint on it will make us ill or lead to your death.
The medical definition of toxicity is straight-forward:
“Medical Definition of Toxicity (LD50): the amount of a toxic agent (as a poison, virus, or radiation) that is sufficient to kill 50 percent of a population of animals [or humans] usually within a certain time— called also median lethal dose.” (source 1 or source 2)
The measurement of toxicity is an LD50, or a lethal dose that can kill 50% of exposed persons. In this case, we’re talking about paint that’s on a brush in our mouth. We are concerned with toxicity through an oral route.
An important point: toxicity is dose-dependent. This means the higher amount of agent exposure, the more toxic it is.
For example, to understand the safety of coffee, you may want to know the toxicity of caffeine.
The LD50 or lethal dose of caffeine (not the coffee itself) is ~150–200mg of caffeine per kilogram (kg) of body mass. This data means that you would need to drink more than 50-100 cups of regular coffee to approach a toxic level of caffeine consumption (source). Of course, this is a broad brush, and there is more to consider, e.g., body weight, average caffeine in a cup of coffee.
Why Are My paints Labeled as “Non-Toxic”?
Many acrylic paints designed for miniature painting are non-toxic. This includes many miniature paints; including Games Workshop (Citadel Paint), Privateer Press (P3 Paint) Vallejo, Scale 75, and Reaper Miniatures (Master Series Paint, MSP).
What is the legal definition of the “non-toxic label” in the United States?
Nontoxic materials are not considered to be harmful or destructive to human health. It is to be noted that at some level, every substance is toxic. Therefore, the toxicity must be evaluated in terms of quantity of material. If the quantity of a substance that causes harm is less, its toxicity is determined to be higher (source).
This means that acrylic paints for miniatures labeled “non-toxic” can still be harmful. The risk for harm is based on your level of exposure to the paint. In other words, normal paint handling, e.g., painting a mini, paint on your skin, is considered legally safe. But, the non-toxic label does not account for unintended use, such as brush licking.
What is the Oral Dose of Paint Required to Kill a Miniature Painter?
Companies label acrylic paint products as non-toxic base this term on “normal-use”. It is fair to say that paint brush licking falls outside the normal-intended use defined by legal standards.
For an interesting article on historically dangerous brush-licking, visit here. Let’s dig deeper into the painting dose required to hurt you if you actually consume paint through licking your brush.
To do this, we can look up the Safety Data Sheets (SDS) provided for acrylic paints. Note that not every company provides these to the public through online sources.
Games Workshop, Scale 75, Privateer Press, and Reaper Miniatures do not have their SDS sheets available on the internet. But, it should be possible to get these SDS documents from these companies by contacting them directly.
By law in many countries, companies must make their product safety information, e.g., MSDS or SDS, available to consumers upon request.
Any acrylic paint that contains toxic chemicals purchased in the United States (or other developed country) will have its toxicity marked on its label or box.
Games Workshop, Scale 75, and Reaper Miniatures list almost all of their paint lines as non-toxic. Games Workshop states for its line of Citadel paint that: “All of our paints are non-toxic, water-based acrylic that are designed for use on plastic, metal, and resin Citadel miniatures.”
Vallejo is the only company of the major brands that provides an accessible safety listing with SDS documents of their paint lines (see safety info here).
An Opinion Based on Limited Data
To form an opinion on the topic of paint lethality, we will use the SDS LD50 safety information from one line of Vallejo paint to understand if brush licking yields any immediate lethal risk for a miniature painter.
To formulate an opinion using limited data, we must make assumptions.** For example, if all paint lines are the same formulation as Vallejo (same ingredients, such as pigments, mediums, flow improvers, etc.), then it is possible extrapolate these data and findings to the other paint brands.
Vallejo lists their safety information conveniently on their website (here). They have a listing of all their paint lines, including Vallejo Model Color, Game Color, Metallic Color, and many others.
If we pull the Model Color, Game Color, and Metallic Color SDS sheets and look at the toxicology information, this is what we get:
- Model Color = LD50 oral > 5000 mg/kg (rat)
- Game Color = LD50 oral > 2000 mg/kg (rat)
- Metallic Color = “toxicological properties…is not available.”
Model Color Paint is “less toxic” than Game Color for brush licking, because you need to consume more Model Color paint to reach its LD50. Now, when we say less toxic, we mean it has a higher dose threshold for risk (5000 versus 2000 mg/kg). Of course, the toxicology data is based on studies in rats of oral consumption, but we might expect this to be same for humans (source).
Vallejo Metallic Color paints have no toxicology information. This is kind of a warning sign that metallic paints, in general, may have hidden risks that we can’t speculate about because we don’t have enough data.
As we stated earlier, all of this data means that if you lick your brushes you’re likely not going to die in a single sitting. You can’t consume enough paint to reach the dose threshold for acutely lethal effects on your body.**
How Much Paint Can I Lick: What is the Lethal Dose of Acrylic Hobby Paint?
An average adult human male or female has a body mass of 70kg (154 lbs) (source). If we do the calculations (not all shown here), a human would need to consume about 140 grams of Vallejo Game Color paint.
A typical bottle of Vallejo Game Color paint is about 17 ml liquid volume (or 26.5 grams of paint, if we calculate using the density of Vallejo Black Game Color paint – see SDS).
So, for you to have a 50% risk of dying from Vallejo Black Game Color Paint, you would need to consume via brush licking more than ~5 bottles in less than 24 hours (e.g., acute toxicity).
And, this is if you weighed 70 kilograms. If you weigh more, you could reasonably consume more than this estimate before getting to lethal levels of paint consumption.
If you are concerned with safety, please do the research and form your own opinion.
This article only discusses the question of brush licking or paint consumption through an oral route in the acute setting.
In addition to using the LD50 values from the product SDS documents, there are other potential hazardous implications. But, I have not detailed these here for lack of available safety information.
Importantly, the chemicals you need to avoid consuming that could be in acrylic paint brands include chromium, cadmium, cobalt, manganese, and lead.
Note that cadmium and cobalt are also parts of the names of paint colors, e.g., cobalt blue. Acrylic paints should not contain these chemicals if they carry a non-toxic label.
The lack of dangerous health implication data suggests that you should speculate on safety with caution.
To the question whether brush-licking in typical miniature acrylic painting is dangerous, the answer is scientifically “unclear”.
The article is an opinion of safety risk associated with brush licking. There are many other risky behaviors and chemicals we would be more concerned with in the miniature painting hobby (e.g., airbrushing in an enclosed space, paint thinners, aerosol primers, enamel varnishes), which carry explicit warnings. Ultimately, whether or not to engage in a particular hobby activity is a personal choice.
Non-toxic labeled acrylic paints formulated for miniature painting are likely safe if you accidentally consume paint from brush licking.
Lick your brushes at your own risk.
This article is an opinion-piece based on Vallejo paint SDS LD50 information that is available on the internet. The author extrapolated data to other paint brands on assumption that non-toxic labeled paints carry similar lethal toxic risk. This assumption excludes the possibility that other brands of acrylic paint may have different acute lethal toxicology risks, e.g., LD50 levels.
The article also forms an opinion specifically regarding the question of toxicity issues related to brush licking and accidental acrylic paint consumption through an oral route and only in the acute setting (e.g., total concentration consumed in no more than 24 hours).
There is no data available to assess the potential chronic toxicity or cumulative hazards associated with long-term brush-licking. Additionally, this article does not account for purposeful misuse of paint outside its intended-use, prolonged exposure to acrylic paint on any external or internal part of the body, or the actual oral consumption of acrylic paint labeled “non-toxic”.
There is also not enough scientific evidence to conclude a rigorous safety determination of brush licking due to a lack of evidence across several other dangerous health implications associated with acrylic paint exposure: These include: 1) ingestion, 2) inhalation, 3) contact with skin or eyes, 4) CMR (i.e., carcinogenicity, mutagenicity, and reproductive toxic effects), 5) sensitizing effects, 6) specific target organ toxicity (STOT) due to acute or chronic exposure, and 7) aspiration hazard.