Common Solvents (Volatile Organic Compounds-VOC’s) and Their Health Hazards
Are All Voc’s Hazardous to Health?
Are Mineral Spirits, Petroleum Distillates, Petroleum Naphtha, Stoddard Solvent, VM&P Naphtha, Lacquer Thinner, Painters’ Naphtha, Turpentine, Isopropyl Alcohol, Methyl Alcohol, Toluene, Acetone, and Xylene all the same? Are they hazardous?
The answer is NO! YES.
No, they are not the same because each one is chemically different.
Yes, because they all are hazardous to some degree from ingestion, inhalation and to a lesser degree absorption through the skin. The following is a summary of the hazards of each solvent:
Mineral Spirits is probably the most common solvent but the same chemical mixture of hydrocarbons is often referred to as Stoddard Solvent, Petroleum Distillates, Petroleum Naphtha or White Spirits. Mineral Spirits are often used for thinning oil-based paints, cleaning brushes and cleaning/degreasing machine and auto parts. There are several types of mineral spirits since it is not a specific chemical but a combination of hydrocarbons usually with sulfur removed by distillation and other distillations is intended to remove the odors and aromatic hydrocarbons—the most hazardous of which is benzene. Mineral Spirits can remove protective skin oils and increase the possibility of rash, or dermatitis. They are dangerous if ingested most importantly because they can aspire into the lungs. Inhalation of higher concentrations of Mineral Spirits can result in respiratory irritation or even pulmonary edema. The possibility of any severe health effects due to exposure to Mineral Spirits is remote under normal use but care should always be taken to protect skin and lungs where use is lengthy or extreme. It should be noted that outside the U.S., Mineral Spirits are generally called White Spirits.
VM&P Naphtha refers to a paint thinner/cleaner and solvent whose formal name is Varnish Makers and Painter Naphtha = thus VM&P Naphtha. This is generally a lighter more volatile solvent than Mineral Spirits. The lighter hydrocarbons are called Aliphatic hydrocarbons. Those lighter hydrocarbons are more hazardous than the heavier ones in solvents like Mineral Spirits. They evaporate faster and thus can be inhaled in greater concentrations and more significantly damage our lungs, liver, kidneys and even skin.
Lacquer Thinners are solvent mixtures used to dilute or dissolve certain plastics and resins and can be a combination of a variety of chemicals such as ketones, alkyl esters, and aromatic hydrocarbons. These can be more toxic then the previously mentioned solvents if inhaled, ingested or on the skin. The good thing about lacquer thinners is that current efforts to reduce Volatile Organic Compounds (VOCs) to protect the environment has resulted in a reduction of these bad VOC’s with friendlier—less toxic—VOC’s such as ethylene glycol (antifreeze) and other natural esters from plants. It is important to note that the danger of ethylene glycol is that it has a sweet taste thus possibly a serious threat to young children and animals. Such ingestion which includes aspiration into the lungs can be fatal!
Painters’ Naphtha is usually a solvent similar to Mineral Spirits that is used to dilute oil-based paint and clean brushes and flush out paint spraying equipment also called VM&P Naphtha
Turpentine is something totally different from Mineral Spirits, Naphtha, and Petroleum Distillates in that turpentine is extracted from live trees—usually pine trees. Live trees have their trunks scored and these trees secrete a thick liquid designed to cover the tree wound. This secretion is collected and distilled to produce a special solvent. It is used as an oil paint thinner and varnish thinner and cleaner. Turpentine is much more likely to be a skin irritant and absorbed through intact skin. The vapors are more likely to irritate the eyes, throat, and lungs. It is also more likely to result in kidney damage from high exposure or prolonged exposure. Further, it is highly poisonous if ingested—possibly fatal—even in small amounts.
Isopropyl Alcohol (also called isopropanol) is the very common rubbing alcohol and a common solvent for personal use, as well as light industrial uses. It evaporates quite rapidly so it is often used as a disinfectant and a cleaning agent and is water-soluble. It is even used to solubilize water in gasoline and referred to as a “gasoline dryer.” Although not highly toxic, it is a poison when ingested. Because it evaporates rapidly, inhalation should be minimized. If used for parts cleaning in industry, good ventilation and often respiratory protection are required. In fact, anywhere it is used in industry efforts should be made to minimize inhalation if used on a regular or continuous basis.
Methyl Alcohol (also called methanol) is an alcohol similar in its evaporation rate to isopropanol. It used to be called “wood alcohol” because it was commonly distilled from wood but now it is made commercially by combining carbon monoxide and hydrogen. Also, it is water-soluble and used as a cleaning agent. It is, however, more toxic than isopropanol. It is not generally available for personal use because it is quite poisonous. Its main uses are as an anti-freeze, paint thinner, paint remover, even as a windshield wiper fluid. Ingestion can result in multiple organ damage including blindness. In an industry where methanol is made or packaged, ingestion or inhalation must be minimized. This is often through complete containment in a closed system for industrial uses, ventilation, and respiratory protection are very important, as well as prevention of ingestion.
Toluene-OSHA says this is the most frequently sampled chemical in the American workplace. It is an aromatic hydrocarbon ( a benzene ring with 1 methyl group). It is colorless and has a paint thinner smell. It is a common industrial feed-stock, paint thinner, and often contained in printing inks, airplane glue, adhesives and is often used in many chemical reactors. it is considered to be toxic and is specifically regulated by OSHA. The 8-hr permissible exposure level (PEL) is 200 ppm but ACGIH recommends an 8-hr time-weighted average (TWA) of 20 ppm. Toluene exposure is to be minimized for pregnant individuals or those intending to become pregnant.
Acetone is a very volatile chemical that has both personal and commercial uses. It is the main ingredient in nail polish remover and also fast drying nail polishes. It has a strong odor mainly because it evaporates so fast. It is the simplest form of a group of chemicals called ketones but isn’t as toxic or hazardous as most other ketones. What is unusual is that our body produces it and disposes of it as a normal process. People who are diabetic generally produce more of it which can lead to ketoacidosis. Exposure to acetone should be avoided by those who are pregnant or intend to become pregnant since it has been shown some ability to cause reproductive effects. In industry, it is often used as a paint solvent, paint thinner, degreasing agent, and some medical uses since it can be cooled without freezing. It has other medical uses as well. Also, acetone is used as a base chemical in many chemical reactions. Its main hazard is its flammability. Because it evaporates so fast, it can easily reach a combustible/flammable stage. Since it is not highly toxic, there are only a few cases where ventilation is necessary except to control its flammability. Respiratory protection is usually not recommended because the filters (usually charcoal) get filled up so rapidly.
Xylene is also a relatively common solvent in many commercial and industrial uses. It is also an aromatic hydrocarbon with a benzene ring base. There are only limited cases where xylene can present an overexposure situation in its commercial uses. Because it is not very volatile, it is difficult to create enough airborne xylene to exceed safe worker exposure levels. Respiratory protection is an effective means of controlling worker exposure to any of the 3 different forms of xylene (o, m, p, xylene).
These are just a very few of the solvents available. There is a vast variety of other solvent type chemicals used in industry as coatings, degreasers, resins, solvents, inks, paints, and in chemical reactions most of which tend to be equally toxic or more toxic than the mere common chemicals discussed in this article. The hazardous characteristics of these chemicals are generally known but the combination and mixtures cause considerable concern because of the possible cumulative and synergistic effects of a blend of such chemicals.
The first line of defense is to request a Safety Data Sheet (SDS) whether you are a consumer or an industrial user of such solvents and chemicals. The next step is to get assistance from an Industrial Hygienist, Toxicologist, or another qualified expert to interpret the possible effects and the protections needed to handle them safely.