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      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-ol[1]
                             OPPTS Guideline No. 
                                   Property
                             Description of Result
                                   830.6302
Color
Colorless
                                   830.6303
Physical State
Liquid
                                   830.7220
Boiling point/Range
180.32 [0]C
                                   830.7550
                                   830.7560
                                   830.7570
Partition Coefficient (n-
Octanol/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. 


