Volatility and Organic Compounds Explained
Many dangerous substances can reduce air quality. These environmental pollutants have distinct characteristics and cause unique side effects in people with asthma and the general population. While it's good to understand things like the units of measure for volatile organic compound, or VOC, safety levels, it's also wise to know how such substances differ from other chemicals. Here's a practical primer on the science.
In chemistry, the term organic refers to the majority of chemical compounds that include carbon atoms, such as many of the building blocks of life. There are a number of important exceptions to this rule, such as carbon dioxide and carbon monoxide, which are classified as inorganic.
For a substance to be volatile, it has to tend to change state without needing much extra prompting or special conditions. Many carbon-bearing organic compounds, such as the paints and coatings that might set off a smart indoor air quality monitor, exhibit this tendency by evaporating from liquids and solids into gases seemingly unprompted. For instance, vehicles that use hydrocarbon fossil fuels are notorious for filling the air with volatile contaminants, such as benzene and other known carcinogens.
Technicalities of VOCs
Government regulations can confuse these issues. For instance, methylene chloride, widely used in spray paints and certain solvents, is known to have negative health effects, but since it isn't as likely to decompose, the U.S. government gives it a pass by excluding it from its list of controlled VOCs.
In the U.S., many other known hazardous substances, such as multiple CFCs and acetone, also fall into this less-strict compliance category. It's important to remember, however, that this doesn't make it safe for humans to be exposed to these chemicals, especially if they have asthma.
The Situational Risks of Exposure
Those who want to protect their health can't only base their decisions on a volatile organic compound's regulatory status. Factors like people's living and working arrangements have important effects on which VOCs are the most dangerous. For instance,EPA data* suggests that indoor spaces often contain significantly higher concentrations of many risky organic chemicals. Certain activities, such as stripping paint, can cause massive concentration spikes.
There's also a big difference between hazardous VOCs and hydrocarbons, which only include carbon and hydrogen atoms. While hydrocarbons like petroleum and gasoline might not pose huge risks inside a typical household, benzene and others are especially likely to build up and cause problems as a side effect of behaviors like cigarette smoking. Some building materials cause VOC emission issues, like certain types of laminate flooring, coatings, underlay, adhesives and carpet backing.
Not all organic compounds are volatile. Also, understanding VOC concentration levels is just one aspect of a proactive indoor environmental protection strategy. For instance, exposure to everything from nitrogen oxides to the drycleaning chemicals around a retail clothing department can be problematic for people living with asthma. In other words, it's best to take a whole-picture view of environmental compliance.