UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

 WASHINGTON, D.C. 20460

OFFICE PREVENTION, 

PESTICIDES AND TOXIC SUBSTANCES 

MEMORANDUM January 09, 2013

SUBJECT: Ecotoxicity Risk assessment for Octenol Registration Review Decision 

Document. 

EPA Reg No.: 72563-

Registration Review 

Case#: 6033

CAS No.: 3391-86-4

PC Code: 069037

FROM: Miachel Rexrode, Ph.D., Senior Biologist /s/ 01/09/2013

Biochemical Pesticides Branch

Biopesticide & Pollution Prevention Division (7511P)

TO: Leonard Cole, Regulatory Action Leader /s/ 01/09/2013

Biochemical Pesticides Branch

Biopesticide & Pollution Prevention Division (7511P)

ACTION REQUESTED

The following is an ecotoxicity assessment for octenol in support of the Registration Review 

Work Plan. 

RECOMMENDATIONS AND CONCLUSIONS

Executive Summary

Octenol (1-Octen-3-ol) is a naturally occurring straight chain aliphatic alcohol by-product that is 

produced in plants and animals. It was originally reported to be found in mushrooms and has 

been isolated also from the essential oils of lavender. Octenol is found in fruit (bananas, melons, 

currants, and filberts), vegetables (asparagus, tomatoes), cheese, fish, meat (chicken), coffee, tea, 

etc. This compound is a semiochemical which modifies the behavior of some insects and when 

used as an active ingredient with pesticides, octenol can act as an attractant to certain species of 

mosquitoes and biting flies. It may also be used in conjunction with carbon dioxide and 

electronic devices that in turn kill trapped insects. Studies show that when combined with carbon 

dioxide, octenol can be act as an attractant to many dipterian species that include no-see-ums, 
mosquitoes, and biting midges. The EPA has noted that when octenol is released into air, it is not 

harmful to humans, to non-targeted organisms, or to the environment. There is potential for 

toxicity if octenol is ingested. 

Figure 1.0 1-octen-3-ol

Octenol (l-octen-3-ol) was given Generally Recognized as Safe (GRAS) status by Flavoring

Extract Manufacturers' Association (FEMA). It is also already approved by the U.S. Food and

Drug Administration (FDA) for food use (21 CFR 121.1104). In 1974 the Council of Europe

included octenol in their list of artificial flavoring substances that may be added to foodstuffs

without hazard to public health.

Chemical and Fate Properties

Table 1.0 shows that octenol is not water soluble, has a very low potential for bioaccumulation 

(Log P = 2.60), and is volatile (0.153 mm Hg).

 Table 1.0 Chemical and Fate Properties for 1 –octenol-3-ol1

OPPTS Guideline No. Property Description of Result

830.6302 Color Colorless

830.6303 Physical State Liquid

830.7220 Boiling point/Range 180.32 0C

830.7550

830.7560

830.7570

Partition Coefficient (nOctanol/Water)Log P = 2.60

830.7840 Water Solubility Very soluble 1,836 mg/L

830.7950 Vapor Pressure 0.153 mm Hg @ 20°C 

1 EPA 2003, 1-octen-3-ol Fact Sheet

Toxicology

The toxicology values for octenol show that the compound is a Toxicity Category II for acute 

oral toxicity (Oral LD50 = 340 mg/kg); Toxicity Category III for acute dermal toxicity (LD50 = 

3,300 mg/kg); and a non skin irritant. The EPA Fact Sheet also notes that non-published 

summary information shows that octenol acute inhalation is Toxicity Category IV (LC50 = 3.72 

mg/L) and that the compound is a component of some perfumes (1%) where there have not been 

any incidents of eye or respiratory effects.

Ecological Effects

The Agency has waived all ecological data requirements and noted that it does not expect a risk 

to non-target wildlife from the proposed uses of octenol (i.e., mosquito and biting fly lure for bug 

zapper and traps) due to the low exposure anticipated in the formulated product (i.e., Flowtron 
Octenol Mosquito Attractant). Although octenol is acutely toxic to mammals on an oral basis

((LD50 = 340 mg/kg), the compound is packaged in a multilayer, plastic laminate construction 

and housed in an applicator before it is used in a device (electronic) that can kill/trap insects. A 

review (11/27/12) of the Agency Environmental Incident Information System (EIISv2.1.1; 2012) 

showed that there were no reports of adverse effects from octenol exposure to non-target species

Conclusions

Octenol is a semiochemical that acts by modifying behavior of the pest species and appears to be 

an attractant of hematophagous arthropods, especially dipterans. The compound is very water 

soluble but the vapor pressure for octenol shows that the compound is highly volatile and the log 

kow shows a limited potential for bioconcentration. The Agency waived the requirements for 

toxicity studies on this compound based on the following: packaging methods; the small load 

per unit/applicator; relatively slow evaporation rate of 2- 3 mg/hr (Kulasewski, 2002); the 

widespread occurrence of this compound in plants, animals and edible fruits/vegetables; approval 

by the US Food and Drug Administration for use in food; and octenol is a Generally Recognized 

as Safe (GRAS) compound. The use of octenol as an attractant is not expected to result in 

increased lethal exposure to non target organisms that is above normal background levels; 

consequently, adverse effects to these terrestrial and aquatic organisms is low and effects to 

endangered/threatened species is a No Effect. 

References

Kulasewski, J. 2002. Determination of the release rate of Mosquito Magnat Octenol Lure. 

American Biophysics Corp. MRID 4814920

Touhey, J.G. 1990. A review of the current bases for the United States Environmental Protection 

Agency's policies for the regulation of pheromones and other semiochemicals, together with a 

review of the available relevant data which may impact the assessment of risk for these classes of 

chemicals. Part 1: straight chain alcohols, acetate esters and aldehydes. Unpublished report.