For those curious about the two mixing fluids available for PV's, here's a breakdown between Propylene Glycol and Vegetable Glycerine. Information is provided from two separate sources.
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Propylene Glycol Profile
(excerpts from http://en.wikipedia.org/wiki/Propylene_glycol)
Propylene glycol, also called 1,2-propanediol or propane-1,2-diol, is an organic compound (a diol or double alcohol) with formula C3H8O2 or HO-CH2-CHOH-CH3. It is a colorless, nearly odorless, clear, viscous liquid with a faintly sweet taste, hygroscopic and miscible with water, acetone, and chloroform.
The compound is sometimes called α-propylene glycol to distinguish it from the isomer propane-1,3-diol HO-(CH2)3-OH, also called β-propylene glycol.
Safety for humans:
Propylene glycol is metabolized in the human body into pyruvic acid, which is a normal part of the glucose metabolism process and is readily converted to energy.
The oral toxicity of propylene glycol is very low, and large quantities are required to cause perceptible health damage in humans. Serious toxicity will occur only at plasma concentrations over 4g/L, which requires extremely high intake over a relatively short period of time. It would be nearly impossible to reach toxic levels by consuming foods or supplements, which contain at most 1g/kg of PG. Cases of propylene glycol poisoning are related to either inappropriate intravenous use or accidental ingestion of large quantities by children.
The potential for long-term toxicity is also low. In one study, rats were provided with feed containing as much as 5% PG over a period of 104 weeks and they showed no apparent ill effects. Because of its low chronic oral toxicity, propylene glycol was classified by the U. S. Food and Drug Administration as "generally recognized as safe" (GRAS) for use as a direct food additive.
Prolonged contact with propylene glycol is essentially non-irritating to the skin. Undiluted propylene glycol is minimally irritating to the eye, and can produce slight transient conjunctivitis (the eye recovers after the exposure is removed). Exposure to mists may cause eye irritation, as well as upper respiratory tract irritation. Inhalation of the propylene glycol vapors appears to present no significant hazard in ordinary applications. However, limited human experience indicates that inhalation of propylene glycol mists could be irritating to some individuals. Therefore inhalation exposure to mists of these materials should be avoided. Some research has suggested that propylene glycol not be used in applications where inhalation exposure or human eye contact with the spray mists of these materials is likely, such as fogs for theatrical productions or antifreeze solutions for emergency eye wash stations.
Propylene glycol does not cause sensitization and it shows no evidence of being a carcinogen or of being genotoxic.
There is limited evidence that intravenous injection of propylene glycol can cause adverse responses in a small number of people. A Clinical Journal of Medicine article describes two cases of adult men experiencing psychosis from use of injected phenytoin that contained PG as a solvent. Their symptoms resolved when they were switched to a phenytoin formulation without propylene glycol.
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Vegetable Glycerine Profile
(excerpts from http://www.botanical.com/products/learn/vegetable-glycerine.html)
Botanical Name- Palm derived
Origin- Malaysia
Extraction- Isolated glycerol fats through an Hydrolysis method
Shelf life- 5 years
Notes- Stores well under dark and cool conditions and is extremely volatile to light exposure.
This variety of Glycerine is suitable for food and cosmetic use and is USP standard 99.7% (the rest is water) with no added stabilizers, preservatives and other ingredients.
Specifications:
Color- Clear
Odor/Taste- Flat aroma, very sweet flavor resembling syrup.
Glycerol content- 99.8%
Fatty Acids and Esters- 0.3
Specific Gravity- 1.29
pH- 7
Heavy Metals - <5 ppm
Chlorides- <10 ppm
Chlorinated compounds- <30 ppm
Sulphates- <20 ppm
Moisture- 0.13%
Organic Volatile Impurities- None detected
Diethylene Glycol and related compounds- No trace amounts detected
Vegetable Glyceine
Vegetable glycerine comes to us through a very complex and sophisticated method of extraction known as Hydrolysis, and the end product that we refer to as "Vegetable Glycerine" is usually the by-product of another oils production. The basics of this system is that the fats and oils of a raw ingredient (usually palm or coconut oils) are split into crude glycerol fats, under the combined action of water, temperature and pressure. These temperatures can exceed 400° degrees and the material is usually kept under pressure for 20-30 minutes. What is actually occurring is a sort of "counter-flow" where the water absorbs glycerol from the fatty acid phase of the oil production. After this phase this glycerol is isolated and further distilled to give buyers a standard 99% Glycerine product.
Vegetable Glycerine is a clear, colorless, and odorless liquid with an incredibly sweet taste having the consistency of thick syrup. It is used as an agent in cosmetics, toothpaste, shampoos, soaps, herbal remedies, pharmaceuticals, and other household items. Because it is soluble in both, water and alcohol, its versatility is a major benefactor in its purported growth and popularity within the manufacturing sector. It is invaluable as a natural source ingredient with emollient like properties which can soften and soothe the skin and it assists the outer epidermis is retaining moisture. This helps to explain why it is one of the most popular cosmetic additives used today.
Other uses include its solvency action which aides herbalists in extracting botanical properties from plant materials without the use of alcohol. This is especially helpful for those with alcohol sensitivities as most liquid herbal extracts contain alcohol. But given its severely limited shelf life, extracts made from Vegetable Glycerine typically have a shelf life of 14-24 months whereas alcohol extracts can have an extended shelf life of 4-6 years.
For educational purposes only
This information has not been evaluated by the Food and Drug Administration.
This information is not intended to diagnose, treat, cure, or prevent any disease.
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What does that all translate to for PV'ers? PG tends to vape cleaner, produce more vapor, and has less likelihood of "gunking" up your atomizers. VG is primarily used for individuals that may have a reaction to using PG. While it offers poorer general performance over PG, some users prefer the idea of using something more "organic" (VG) over something more "chemical" (PG).
---
Propylene Glycol Profile
(excerpts from http://en.wikipedia.org/wiki/Propylene_glycol)
Propylene glycol, also called 1,2-propanediol or propane-1,2-diol, is an organic compound (a diol or double alcohol) with formula C3H8O2 or HO-CH2-CHOH-CH3. It is a colorless, nearly odorless, clear, viscous liquid with a faintly sweet taste, hygroscopic and miscible with water, acetone, and chloroform.
The compound is sometimes called α-propylene glycol to distinguish it from the isomer propane-1,3-diol HO-(CH2)3-OH, also called β-propylene glycol.
Safety for humans:
Propylene glycol is metabolized in the human body into pyruvic acid, which is a normal part of the glucose metabolism process and is readily converted to energy.
The oral toxicity of propylene glycol is very low, and large quantities are required to cause perceptible health damage in humans. Serious toxicity will occur only at plasma concentrations over 4g/L, which requires extremely high intake over a relatively short period of time. It would be nearly impossible to reach toxic levels by consuming foods or supplements, which contain at most 1g/kg of PG. Cases of propylene glycol poisoning are related to either inappropriate intravenous use or accidental ingestion of large quantities by children.
The potential for long-term toxicity is also low. In one study, rats were provided with feed containing as much as 5% PG over a period of 104 weeks and they showed no apparent ill effects. Because of its low chronic oral toxicity, propylene glycol was classified by the U. S. Food and Drug Administration as "generally recognized as safe" (GRAS) for use as a direct food additive.
Prolonged contact with propylene glycol is essentially non-irritating to the skin. Undiluted propylene glycol is minimally irritating to the eye, and can produce slight transient conjunctivitis (the eye recovers after the exposure is removed). Exposure to mists may cause eye irritation, as well as upper respiratory tract irritation. Inhalation of the propylene glycol vapors appears to present no significant hazard in ordinary applications. However, limited human experience indicates that inhalation of propylene glycol mists could be irritating to some individuals. Therefore inhalation exposure to mists of these materials should be avoided. Some research has suggested that propylene glycol not be used in applications where inhalation exposure or human eye contact with the spray mists of these materials is likely, such as fogs for theatrical productions or antifreeze solutions for emergency eye wash stations.
Propylene glycol does not cause sensitization and it shows no evidence of being a carcinogen or of being genotoxic.
There is limited evidence that intravenous injection of propylene glycol can cause adverse responses in a small number of people. A Clinical Journal of Medicine article describes two cases of adult men experiencing psychosis from use of injected phenytoin that contained PG as a solvent. Their symptoms resolved when they were switched to a phenytoin formulation without propylene glycol.
---
Vegetable Glycerine Profile
(excerpts from http://www.botanical.com/products/learn/vegetable-glycerine.html)
Botanical Name- Palm derived
Origin- Malaysia
Extraction- Isolated glycerol fats through an Hydrolysis method
Shelf life- 5 years
Notes- Stores well under dark and cool conditions and is extremely volatile to light exposure.
This variety of Glycerine is suitable for food and cosmetic use and is USP standard 99.7% (the rest is water) with no added stabilizers, preservatives and other ingredients.
Specifications:
Color- Clear
Odor/Taste- Flat aroma, very sweet flavor resembling syrup.
Glycerol content- 99.8%
Fatty Acids and Esters- 0.3
Specific Gravity- 1.29
pH- 7
Heavy Metals - <5 ppm
Chlorides- <10 ppm
Chlorinated compounds- <30 ppm
Sulphates- <20 ppm
Moisture- 0.13%
Organic Volatile Impurities- None detected
Diethylene Glycol and related compounds- No trace amounts detected
Vegetable Glyceine
Vegetable glycerine comes to us through a very complex and sophisticated method of extraction known as Hydrolysis, and the end product that we refer to as "Vegetable Glycerine" is usually the by-product of another oils production. The basics of this system is that the fats and oils of a raw ingredient (usually palm or coconut oils) are split into crude glycerol fats, under the combined action of water, temperature and pressure. These temperatures can exceed 400° degrees and the material is usually kept under pressure for 20-30 minutes. What is actually occurring is a sort of "counter-flow" where the water absorbs glycerol from the fatty acid phase of the oil production. After this phase this glycerol is isolated and further distilled to give buyers a standard 99% Glycerine product.
Vegetable Glycerine is a clear, colorless, and odorless liquid with an incredibly sweet taste having the consistency of thick syrup. It is used as an agent in cosmetics, toothpaste, shampoos, soaps, herbal remedies, pharmaceuticals, and other household items. Because it is soluble in both, water and alcohol, its versatility is a major benefactor in its purported growth and popularity within the manufacturing sector. It is invaluable as a natural source ingredient with emollient like properties which can soften and soothe the skin and it assists the outer epidermis is retaining moisture. This helps to explain why it is one of the most popular cosmetic additives used today.
Other uses include its solvency action which aides herbalists in extracting botanical properties from plant materials without the use of alcohol. This is especially helpful for those with alcohol sensitivities as most liquid herbal extracts contain alcohol. But given its severely limited shelf life, extracts made from Vegetable Glycerine typically have a shelf life of 14-24 months whereas alcohol extracts can have an extended shelf life of 4-6 years.
For educational purposes only
This information has not been evaluated by the Food and Drug Administration.
This information is not intended to diagnose, treat, cure, or prevent any disease.
---
What does that all translate to for PV'ers? PG tends to vape cleaner, produce more vapor, and has less likelihood of "gunking" up your atomizers. VG is primarily used for individuals that may have a reaction to using PG. While it offers poorer general performance over PG, some users prefer the idea of using something more "organic" (VG) over something more "chemical" (PG).
