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The information in this profile may be out-of-date. It was last revised in 1996. EXTOXNET no longer updates this information, but it may be useful as a reference or resource.

Please visit the National Pesticide Information Center (NPIC) to find updated pesticide fact sheets. If you don't find a fact sheet related to your question, feel free to call 1-800-858-7378. NPIC is open five days a week from 8:00am to 12:00pm Pacific Time.

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E X T O X N E T

Extension Toxicology Network

Pesticide Information Profiles

A Pesticide Information Project of Cooperative Extension Offices of Cornell University, Oregon State University, the University of Idaho, and the University of California at Davis and the Institute for Environmental Toxicology, Michigan State University. Major support and funding was provided by the USDA/Extension Service/National Agricultural Pesticide Impact Assessment Program.

EXTOXNET primary files maintained and archived at Oregon State University

Revised June 1996

Naled

Trade and Other Names: Trade names for naled include Bromex, Dibrom, Fly Killer-D, Lucanal, and RE 4355.

Regulatory Status: Naled is a moderately toxic compound in EPA toxicity class I. Products containing naled must bear the Signal Word DANGER - POISION because it is corrosive to the eyes. Naled is a General Use Pesticide (GUP).

Chemical Class: organophosphate

Introduction: Naled is a fast acting, nonsystemic contact and stomach organophosphate insecticide used to control aphids, mites, mosquitoes, and flies on crops and in greenhouses, mushroom houses, animal and poultry houses, kennels, food processing plants, and aquaria and in outdoor mosquito control. Liquid formulations can be applied to greenhouse heating pipes to kill insects by vapor action. It has been used by veterinarians to kill parasitic worms (other than tapeworms) in dogs. Naled is available in dust, emulsion concentrate, liquid, and ULV formulations. Unless otherwise specified this profile refers to the technical product of naled.

Formulation: Naled is available in dust, emulsion concentrate, liquid, and ULV formulations. Unless otherwise specified this profile refers to the technical product of naled.

Toxicological Effects:

• Acute toxicity: Naled is highly to moderately toxic via the oral route, with reported oral LD50 values of 91 to 430 mg/kg in rats, and 330 to 375 mg/kg in mice [2,13]. It is moderately toxic through skin exposure; reported dermal LD50 values are 1100 mg/kg in rabbits and 800 mg/kg in rats [2,13]. Naled may cause dermatitis (skin rashes) and skin sensitization (allergies) [2,8], and may be corrosive to the skin and eyes. Mice exposed to 1.5 mg/L in air for 6 hours showed no adverse effects [13]. Naled is used to combat parasitic infestations (such as worms) in dogs at recommended doses of 16.7 mg/kg [2]. Effects due to naled exposure will be similar to those caused by other organophosphate pesticides, including inhibition of cholinesterase and neurological and neuromuscular effects [2]. Symptoms of acute exposure to organophosphate or cholinesterase-inhibiting compounds may include the following: numbness, tingling sensations, incoordination, headache, dizziness, tremor, nausea, abdominal cramps, sweating, blurred vision, difficulty breathing or respiratory depression, and slow heartbeat. Very high doses may result in unconsciousness, incontinence, and convulsions or fatality.
• Chronic toxicity: Chronic exposure to organophosphates may also cause the neurological and neuromuscular effects associated with cholinesterase inhibition [2]. Rats have tolerated a dosage of 28 mg/kg/day for 9 weeks with no visible signs of poisoning and with only moderate inhibition of cholinesterase [2].
• Reproductive effects: No data are currently available.
• Teratogenic effects: No data are currently available.
• Mutagenic effects: Naled did not affect the ability of one bacterial species (Proteus mirabilis) to repair DNA damage, but did increase the frequency of mutations in another bacterial species (Salmonella typhimurium) [8]. These data are insufficient to determine its potential for mutagenicity.
• Carcinogenic effects: No data are currently available.
• Organ toxicity: Naled primarily affects the nervous system through cholinesterase inhibition.

• Fate in humans and animals: Naled is readily absorbed into the bloodstream through the skin and lung and intestinal tissue. Rat studies suggest accumulation may occur in bone [8].

Ecological Effects:

• Effects on birds: Naled is highly to moderately toxic to birds. The reported acute oral LD50 for naled is 52 mg/kg in mallard ducks, 65 mg/kg in sharp-tailed grouse, 36-50 mg/kg in Canadian geese, 120 mg/kg in ring-neck pheasants, and 59 mg/kg in chickens [13,6]. Reported 5- to 8-day dietary LC50 values indicate slight toxicity in species studied. These were 1328 ppm in Japanese quail, 2724 ppm in mallard duck, 2117 ppm in northern bobwhite, and 2538 ppm in ring-neck pheasant [6,13,14].
• Effects on aquatic organisms: Naled is highly to moderately toxic to fish [16]. Reported 96-hour LC50 values range from 0.127 mg/L in cutthroat trout, 0.195 mg/L in rainbow trout, and 0.087 mg/L in lake trout to higher values of 3.3 mg/L in fathead minnow, 2.2 mg/L in bluegill sunfish, and 1.9 mg/L in largemouth bass [16]. The reported LC50 for goldfish is 2 to 4 mg/L [13]. Naled may be very highly toxic to aquatic invertebrate species, with reported 96-hour LC50 values of 0.4 ug/L in Dapnia, 8 ug/L in stoneflies, and 18 ug/L in scuds and sideswimmers [16].
• Effects on other organisms: Naled is toxic to bees [13]. The reported acute oral LD50 in mule deer is 200 mg/kg [6].

Environmental Fate:

• Breakdown in soil and groundwater: Naled is practically nonpersistent in the environment, with reported field half-lives of less than 1 day [19]. It rapidly degrades in the presence of sunlight to dichlorvos [2,13]. For more information on the environmental fate of dichlorvos, see the pesticide profile for dichlorvos. Naled is not strongly bound to soils, but is not highly soluble in water [19]. It is rapidly broken down if wet, and it is moderately volatile [8]. Soil microorganisms break down most of the naled in the soil. It therefore should not present a hazard to groundwater.
• Breakdown in water: Naled is rapidly broken down in water, with a reported half-life of about 2 days [8]. Naled is moderately volatile.
• Breakdown in vegetation: Plants reductively eliminate bromine from naled to form dichlorvos (DDVP), which may evaporate or be further metabolized [13].

Physical Properties:

• Appearance: Technical naled is a colorless liquid with a slightly pungent odor [13].
• Chemical Name: 1,2-dibromo-2,2-dichloroethyl dimethyl phosphate [13]
• CAS Number: 300-76-5
• Molecular Weight: 380.84
• Water Solubility: <1 mg/L @ 20 C [13]
• Solubility in Other Solvents: v.s. in alcohols, aromatic solvents,; s. in aliphatic hydrocarbons, aromatic hydrocarbons, chlorinated hydrocarbons, and ketones; s.s. in mineral oils and petroleum solvents [13]
• Melting Point: 26-27.5 C [13]
• Vapor Pressure: 260 mPa @ 20 C [13]
• Partition Coefficient: Not Available
• Adsorption Coefficient: 180 [19]

Exposure Guidelines:

• ADI: Not Available
• MCL: Not Available
• RfD: 0.002 mg/kg/day [53]
• PEL: 3 mg/m3 (8-hour) [39]
• HA: Not Available
• TLV: Not Available

Basic Manufacturer:

Amvac Chemical Corp.
4100 E. Washington Blvd.
Los Angeles, CA 90023

• Phone: 213-264-3910
• Emergency: 800-228-5635, ext. 169
  

References:

References for the information in this PIP can be found in Reference List Number 5

DISCLAIMER: The information in this profile does not in any way replace or supersede the information on the pesticide product labeling or other regulatory requirements. Please refer to the pesticide product labeling.