At a glance
| Chemical family | Carbamate — N-methylcarbamate insecticide (1-naphthyl methylcarbamate) |
| CAS number | 63-25-2 |
| Classification | Not classified by IARC. EPA classification under review (previous Group D). Reversible acetylcholinesterase inhibitor. WHO Class II (moderately hazardous) |
| Where you encounter it | Garden and lawn insecticide (Sevin); fruit and vegetable pest control; tracked indoors in house dust from treated lawns; some flea powders (legacy use) |
| Sleep micro-environment relevance | Tracked indoors from treated lawns and gardens. Found in house dust in homes with recent outdoor carbaryl application. Reversible cholinesterase inhibitor |
Regulatory & certification status
| European Union | Not approved as a plant protection product. Not authorised for biocidal use in the EU. Regulatory |
| United States | EPA-registered for garden, lawn, and agricultural use. Registration review ongoing (draft human health risk assessment 2022). Available as Sevin in home and garden retail. No indoor use permitted. Regulatory |
| Canada | PMRA-registered. Re-evaluation ongoing. Available for home garden and agricultural use. Regulatory |
| International | Not IARC classified. WHO Class II (moderately hazardous). Available in most markets for agricultural and garden use. Associated with the 1984 Bhopal disaster (manufacturing accident with an intermediate). Regulatory |
What it is
Carbaryl is the 1-naphthyl ester of methylcarbamic acid — a carbamate insecticide developed by Union Carbide (now Bayer CropScience) and first registered in 1959. It is one of the most widely used insecticides in the world, marketed under the trade name Sevin for home garden and lawn use. Carbaryl works by inhibiting acetylcholinesterase in insects, but unlike organophosphate insecticides, the carbamate-enzyme bond is reversible — the enzyme spontaneously decarbamylates within hours. This makes carbaryl less acutely toxic to mammals than most organophosphates. IARC has not evaluated carbaryl in a full monograph. The EPA previously classified it as Group D (not classifiable) and is currently conducting a registration review. Carbaryl is the parent compound of the Bhopal industrial disaster (1984) — the Bhopal plant was manufacturing carbaryl when methyl isocyanate, an intermediate, was released.
Where it shows up in bedding
Carbaryl is not applied to bedding or indoor surfaces. It enters the bedroom through the track-in pathway: when lawns or gardens are treated with carbaryl (Sevin), residues on grass, soil, and hard surfaces transfer to shoes and bare feet, which then deposit the pesticide on indoor floors and carpets. From carpets, carbaryl redistributes to house dust, which can be tracked onto bedding. Studies of the paraoccupational exposure pathway have found measurable carbaryl in house dust samples from homes where the compound was used outdoors. The amounts decrease with distance from the application site and with time since application. Removing shoes at the door is a simple measure that substantially reduces pesticide track-in.
Citations
- EPA (2022). Carbaryl — Draft Human Health Risk Assessment for Registration Review. Source Regulatory
- Curwin, B.D. et al. (2007). Pesticide Contamination Inside Farm and Non-Farm Homes. Journal of Occupational and Environmental Hygiene, 4(5): 357-367. Source Peer-reviewed
- WHO. Carbaryl — International Programme on Chemical Safety (IPCS) Environmental Health Criteria. Source Regulatory
Frequently asked questions
Can Sevin on my lawn contaminate my bedroom?
Yes. When carbaryl (Sevin) is applied to lawns, residues transfer to shoes, bare feet, and pets, which then deposit the pesticide on indoor floors. From floor dust, it can be tracked onto bedding. The amounts are typically small and decline rapidly after application. Removing shoes at the door and keeping pets off treated areas until the product has dried substantially reduces track-in.
Is carbaryl safer than organophosphate insecticides?
In terms of acute toxicity, carbamates like carbaryl are generally considered safer than organophosphates because their cholinesterase inhibition is reversible — the enzyme recovers within hours. With organophosphates, the inhibition can be irreversible, requiring the body to synthesise new enzyme. However, carbaryl is still a cholinesterase inhibitor and can cause symptoms (nausea, headache, muscle weakness) at high exposures.
Related compounds
Embr is a sleep environment company researching and addressing the chemistry of the bedroom. Research and product development in progress.
Last reviewed 2026-07-08. If you find a factual error, contact us.