Soybean oil
Soybean oil is the rare fixed oil with real repellent data behind it: in a landmark trial a 2% soybean-oil spray outlasted every other non-DEET product tested. It anchors botanical sprays like All Terrain's Herbal Armor.
How it works
Refined soybean oil is not strongly repellent on its own. Formulated with a little coconut and geranium oil, as in the products built on it, it forms a barrier and slows evaporation of the volatile actives, which is what stretches protection.
Safety around dogs & cats
A fixed vegetable oil with no meaningful toxicity to dogs or cats; the worst a lick is likely to do is loosen the stool. It carries none of the phenol or terpene load that makes essential oils risky for cats.
Moderate confidence. Ratings from ASPCA Animal Poison Control, the Pet Poison Helpline, and published veterinary toxicology. This is general information, not veterinary advice. If your pet is exposed, call your vet or the ASPCA Animal Poison Control Center at (888) 426-4435.
The evidence
In the 2002 New England Journal of Medicine complete-protection-time study, a 2% soybean-oil product protected for about 95 minutes, the longest of any botanical tested and behind only DEET. That figure belongs to the tested formulation, not to soybean oil in general.
- Comparative efficacy of insect repellents against mosquito bites (complete-protection-time study)2002LabDefinitive evidence
The landmark complete-protection-time study: Fradin and Day timed how long 16 store-bought repellents kept Aedes aegypti from biting, in controlled arm-in-cage tests with 15 volunteers. It is the study that put hard numbers on the idea that DEET lasts and botanicals do not.
Products using it
Natrapel
Natrapel Essential Oil Insect Repellent
Cedarwood oil 1.50% · Clove oil 0.25%
Complete protection
Badger
Anti-Tick Spray
Thyme oil 1.0% · Geraniol 4.5%
Complete protection
Badger
Anti-Bug Shake & Spray
Castor oil 10% · Cedarwood oil 2%
Complete protection
Maggie's Farm
Maggie's Farm Natural Insect Repellent
Citronella oil 0.95% · Clove oil 0.50%
Complete protection
All Terrain
Herbal Armor DEET-Free Natural Insect Repellent Pump Spray
Cedarwood oil 1.5% · Citronella oil 10%
Complete protection
Not recommended
Potentially not EPA compliant
Jao
Jao Patio Oil Moisturizing Mist
Oil of Lemon Eucalyptus 20% · Geraniol 5%
Complete protection
Not recommended
No proven mosquito protection
Murphy's Naturals
Mosquito Repellent Wipes
Cedarwood oil 1.4% · Citronella oil 0.2%
Complete protection
Not recommended
Formula not fully disclosed +1 more
Skeem Design
Skeem Verbena Aura Citronella Body Spray
Citronella oil · Lemongrass oil
Complete protection
Regulatory notes
EPA minimum risk (FIFRA 25(b)) approved active ingredient; matched to SRS registry entry.
Safety notes
A culinary oil, mild on skin and low-risk for pets, though people with a soy allergy may react. It is one of the gentler repellent bases.