Nitrocellulose has very low chemical toxicity to humans. Your body cannot absorb it through the skin, lungs, or digestive tract in any meaningful way, and it passes through the gastrointestinal system essentially unchanged. The real danger from nitrocellulose is not poisoning but its extreme flammability. When it burns or decomposes, however, it releases gases that are genuinely toxic.
Why Your Body Can’t Absorb It
Nitrocellulose is made by treating ordinary plant cellulose with nitric acid. The resulting molecule is far too large and chemically stable to cross biological membranes. A U.S. EPA health advisory states plainly: “There are currently no available data to suggest that nitrocellulose can be absorbed from any route.”
Animal studies back this up. When rats were given repeated oral doses of radiolabeled nitrocellulose (tagged so researchers could track it), no detectable radioactivity appeared in any tissue or body fluid. The only places it turned up were in the digestive tract and in feces. Because mammals, including humans, lack the enzymes to break down cellulose fibers, nitrocellulose simply travels through the gut and exits the body. It is not digested, not metabolized, and not absorbed into the bloodstream.
Inhalation and Skin Contact
While swallowing nitrocellulose is essentially a non-event biologically, breathing it in is a different story. Nitrocellulose dust and fibers can irritate the nose and throat. At higher exposures, symptoms include headache, nausea, vomiting, dizziness, difficulty breathing, and loss of consciousness. These effects are tied to the physical irritation of airborne particles and any residual solvents present in industrial settings, not to the nitrocellulose molecule being absorbed into your system.
Direct skin contact with solid or wetted nitrocellulose is not associated with significant toxicity. In consumer products like nail polish, where nitrocellulose is one of the main film-forming ingredients, allergic contact dermatitis can occasionally occur. A study in the Journal of Drugs in Dermatology found that about 4% of patients with periorbital eczema (skin irritation around the eyes) traced it back to nail polish use. That said, toluene/formaldehyde resin, not nitrocellulose itself, is the more common allergen in those products.
The Real Hazard: Fire and Decomposition
Nitrocellulose is classified primarily as a fire and explosion hazard rather than a health hazard. It ignites easily, burns rapidly, and can self-ignite if stored improperly. The toxicity concern arises when it burns. Thermal decomposition produces carbon monoxide, nitrogen oxides, and other toxic fumes. These gases are dangerous to inhale and are the reason safety data sheets call for self-contained breathing apparatus during nitrocellulose fires.
This distinction matters: nitrocellulose sitting in a jar or applied to your nails is not releasing toxic compounds. Nitrocellulose on fire is a serious inhalation hazard.
Use in Food Packaging and Medicine
The FDA lists nitrocellulose as an authorized indirect food additive under multiple sections of its food contact regulations (21 CFR Parts 175 through 181). It is approved for use in coatings, adhesives, and packaging materials that come into contact with food, reflecting its low biological toxicity profile.
Nitrocellulose also appears in medical products. Pyroxylin, a form of nitrocellulose dissolved in a solvent, is the active film-forming ingredient in many liquid bandages. A recent study in mice found that a pyroxylin-based liquid bandage reduced inflammation, promoted wound contraction, decreased scarring, and prevented scab formation compared to untreated wounds. The film sits on the skin surface without causing tissue toxicity, which is consistent with what we know about the molecule’s inability to penetrate biological barriers.
Environmental Persistence
In the environment, nitrocellulose behaves much like it does in the human body: it just sits there. Direct biodegradation of nitrocellulose is not feasible under natural conditions. Once it settles into sediment, it is extremely stable and may persist indefinitely. A Defense Department review concluded that “nitrocellulose will remain in the environment essentially unchanged and any harmful effects will be restricted to its habitat alteration effects,” meaning the physical presence of the material rather than any chemical poisoning.
Aquatic toxicity is remarkably low. Testing across four species of small invertebrates, four fish species, and three algae species found that lethal or harmful concentrations consistently exceeded 1,000 milligrams per liter. For context, that is an extraordinarily high threshold. Most truly toxic substances harm aquatic life at concentrations measured in micrograms, not grams. The lowest value recorded was 579 mg/L for a single algae species, still far above levels that would occur in real-world water contamination scenarios.
Putting the Risk in Perspective
Nitrocellulose occupies an unusual spot on the hazard spectrum. As a chemical entering your body, it is remarkably inert. It does not get absorbed, does not accumulate in tissues, and does not appear to cause cancer or organ damage at any tested dose. As a physical material, though, it is one of the more dangerous substances you can store, because it catches fire with minimal provocation and the fumes from that fire are toxic.
If you encounter nitrocellulose in everyday products like nail polish, liquid bandages, or food packaging coatings, the toxicity risk is negligible. If you work with bulk nitrocellulose in industrial or laboratory settings, the primary concerns are proper ventilation to avoid inhaling dust and strict fire safety protocols to prevent ignition.