Piperonyl butoxide Chemical Properties

Melting point:

<25 °C

Boiling point:

180 °C

Density 

1.059 g/mL at 25 °C(lit.)

vapor pressure 

0.02 hPa (60 °C)

refractive index 

n20/D 1.498(lit.)

Flash point:

>230 °F

storage temp. 

2-8°C

solubility 

water: slightly soluble0.0289g/L at 20.4°C

form 

Liquid

Specific Gravity

1.060 (20/4℃)

color 

Clear yellow

Odor

mild odor or odorless

Water Solubility 

<0.1 g/100 mL at 18 ºC

Merck 

14,7476

BRN 

288063

Stability:

Stable. Combustible. Incompatible with oxidizing agents.

InChIKey

HHZWGSFIZRNPFB-UHFFFAOYSA-N

LogP

4.750

CAS DataBase Reference

51-03-6(CAS DataBase Reference)

NIST Chemistry Reference

Piperonyl butoxide(51-03-6)

IARC

3 (Vol. 30, Sup 7) 1987

EPA Substance Registry System

Piperonyl butoxide (51-03-6)

Safety Information

Hazard Codes 

N,T

Risk Statements 

50/53-51/53-24

Safety Statements 

60-61-45-36/37/39-28A

RIDADR 

UN 3082 9/PG 3

WGK Germany 

3

RTECS 

XS8050000

TSCA 

Yes

HazardClass 

6.1(b)

PackingGroup 

III

HS Code 

29329990

Hazardous Substances Data

51-03-6(Hazardous Substances Data)

Toxicity

LD50 orally in female, male rats: 6150, 7500 mg/kg (Gaines)

MSDS

• Language:English Provider:ACROS
• Language:English Provider:SigmaAldrich

Piperonyl butoxide Usage And Synthesis

Description

Piperonyl butoxide (PBO) is a water insoluble colorless to pale yellow liquid that was developed in the 1940s to increase the effectiveness of various pesticides. It is currently registered as an active ingredient in more than 1500 products used for indoor or outdoor pesticides, including agricultural maintenance of some food crops.

Chemical Properties

Piperonyl butoxide (PB) is a Light Yellow Liquid. It has no smell or a faint smell and a slightly bitter taste. It does not dissolve in water but can be dissolved in mineral oil and most organic solvents. It is stable to light, resistant to hydrolysis, and is not corrosive. In terms of toxicity, the LD50 (lethal dose for 50% of a test population) is 7500mg/kg in rats when administered orally.

Uses

Piperonyl butoxide is used as a synergist for pyrethrins and their synthetic analogues. It is typically added to carbamate, pyrethrin, pyrethroid, and rotenone pesticides to greatly enhance their potency. PBO alone does not have pesticidal properties.

Preparation

First, safrole is obtained from allyl chloride and methylenedioxybenzene. Then, piperonyl butoxide is produced by catalytic hydrogenation, chloromethylation, and etherification reactions.

Definition

ChEBI: Piperonyl butoxide is a member of benzodioxoles. It has a role as a pesticide synergist.

General Description

Pale yellow to light brown liquid with a mild odor and a faint bitter taste.

Air & Water Reactions

Insoluble in water.

Reactivity Profile

Piperonyl butoxide can react with oxidizing materials.

Fire Hazard

Piperonyl butoxide is combustible.

Agricultural Uses

Insecticide synergist: A U.S. EPA restricted Use Pesticide (RUP). Not listed for use in EU countries. Piperonyl butoxide is a synergist, i.e., not a pesticide itself, but enhances the properties of other chemicals. It is used with other pesticides such as pyrethrins, pyrethroids, rotenone and carbamates in food and non-food agricultural products, home and garden products, termite and mosquito products, and veterinary pesticide products. It inhibits the insect’s ability to break down an insecticide before it takes effect, thereby prolonging the action, and reduces the necessity for using a stronger formulation.

Trade name

Trade names have included Butoxide, Butacide, Butocide, and Pyrenone (mixture with allethrin).

Safety Profile

Poison by skin contact. Moderately toxic by ingestion and intraperitoneal routes. An experimental teratogen. Experimental reproductive effects. Many glycol ether compounds have dangerous human reproductive effects, Questionable carcinogen with experimental tumorigenic data. Mutation data reported. Combustible when exposed to heat or flame; can react with oxidizing materials. To fight fire, use foam, CO2, dry chemical. When heated to decomDosition it emits PLATINOL 0 cis-PLATlNUM(II) DIAMMINE- DICHLORIDE

Environmental Fate

PBO is rapidly degraded (half-life 8 h) in the environment by photolysis and is metabolized by soil microorganisms. Its estimated atmospheric half-life is approximately 3 h.

Metabolic pathway

Piperonyl butoxide is used primarily in admixture with pyrethrins and some of the pyrethroids to enhance and prolong their insecticidal action. Much of this use is in domestic and industrial situations. Metabolism studies were conducted soon after its discovery and first use in the 1950s and 1960s. The main impetus initially was to understand the mode of action as a synergist. When this was shown to be due to the inhibition of oxidative metabolism, further studies were conducted to address possible toxic interactions with other pesticides and drugs in man.
Piperonyl butoxide undergoes rapid photodegradation and microbial degradation in soil. It is also rapidly metabolised in insects and mammals by oxidative attack at the methylenedioxy carbon atom and in the side chain. A comprehensive review by Casida (1970) describes the chemistry, mode of action and metabolism of piperonyl butoxide and several related methylenedioxyphenyl compounds. Though published nearly 30 years ago, the review remains a very useful compilation of a large amount of information, supported by more than 300 references.

Degradation

Piperonyl butoxide is stable to hydrolysis at pH 5,7 and 9 in sterile buffers in the dark at 25 °C. It is rapidly degraded in aqueous solution at pH 7 in sunlight with a DT₅₀ of 8.4 hours (PM). The compound was found to be relatively stable under a variety of irradiation conditions as a thin film on glass or in organic solvent (methanol, benzene and cyclohexane). Loss of the butoxyethoxy side chain was observed to give 5-methyl-6-propyl-l,3- benzodioxole (2), butoxyethanol (3) and ethanediol (4) (Fishbein and Gaibel, 1970). These studies did not utilise radiolabelled compound. The partial pathways are shown in Scheme 1.

Toxicity evaluation

Piperonyl butoxide has low to very low toxicity in birds.Researchers consider piperonyl butoxide moderately toxic to fish，although it is unlikely to accumulate.Some aquatic invertebrates may be highly sensitive to this compound.
As a synergist, PBO inhibits mixed-function oxidases, including cytochrome P450, and resistance-associated esterases that allow insects to degrade an insecticide, allowing enhanced insecticide efficacy. It does not effectively act as a synergist in mammals.

Piperonyl butoxide(51-03-6)Related Product Information

• Ethylparaben
• Diphenolic acid
• Ethanol
• Ethyl acrylate
• Buprofezin
• DL-α-Tocopherol
• Benzyl chloride
• Benzyltriethylammonium chloride
• Benzyltrimethylammonium chloride
• 4-(Diethylamino)salicylaldehyde
• DI(PROPYLENE GLYCOL) BUTYL ETHER
• PETROLEUM ETHER
• Ethylbenzene
• 3-Mercaptopropyltriethoxysilane
• 2-Butoxyethanol
• 2-Butoxyethyl acetate
• Cyhalofop-butyl
• Dimethyl ether