Low water solubility and high vapor are two distinguishing marks of volatile organic compounds (VOCs). These synthetic chemicals are usually released during the manufacturing of pharmaceuticals, paints, and refrigerants.
A wide variety of products may emit VOCs, including paint thinners, cleaning supplies, furnishings and construction materials, pesticides, and more. Made up of different types of chemicals, most VOCs have long-term health repercussions.
The Environmental Protection Agency (EPA)’s Total Exposure Assessment Methodology found that VOC levels are at least two to five times higher indoors when compared to outdoors. These compounds are common groundwater pollutants, wreaking havoc on human health.
In this article, we will delve deeper into the hazards associated with VOCs in water, their types, and whether a reliable solution is available.
The Notorious History of Volatile Organic Compounds in Water
Not all VOCs are man-made – a significant portion is also produced by plants (isoprene being the main compound). However, the synthetic kinds are among the most dangerous, often produced as a result of cleaning by-products.
These compounds have a dark history, with the most tragic case of water contamination being North Carolina’s Camp Lejeune. This US Marine Corps Base was established as an amphibious training facility for military members.
However, matters spiraled downwards towards the latter half of the 1980s. It was discovered that three water supply tanks across the Base – at Hadnot Point, Tarawa Terrace, and Holcomb Boulevard – were severely contaminated.
The contamination’s origins were traced to an offsite dry cleaning facility. It was suspected that the situation may have persisted for nearly three decades before being discovered.
The primary contaminants present in the Camp’s waters included VOCs like trichloroethylene (TCE), vinyl chloride, and tetrachloroethylene/perchloroethylene (PCE). These chemicals went undetected for decades because they are odorless and colorless.
Veterans and their civilian families suffered severe injuries like life-threatening cancers, birth defects, infertility issues, Parkinson’s disease, and more. Under the Obama administration, all were offered free healthcare but President Joe Biden made legal justice possible.
In August 2022, he officially passed the Camp Lejeune Justice Act (CLJA). This does not mean victims can directly file a Camp Lejeune contaminated water lawsuit. They must first file an administrative claim with the Navy Judge Advocate General (JAG).
If no resolution is made within six months, a lawsuit could be filed. According to TorHoerman Law, both claims and lawsuits are being filed and the litigation is progressing in the North Carolina Federal court. After the Bellwether trials, it is expected that victims will receive fair compensation for their injuries.
The Camp Lejeune incident goes down into US history as the worst-ever case of water contamination, affecting over one million people. This alone must tell us the damage VOCs in water is capable of causing.
The Three Most Common Waterborne VOCs
Now, let’s discuss the three most common VOCs found in water.
Methyl Tert-Butyl Ether
As per the Centers for Disease Control and Prevention (CDC), methyl tert-butyl ether is a highly flammable liquid and frequently contaminates groundwater. Due to these reasons, this waterborne VOC is banned across several US states.
Currently, its applications are limited to certain medical uses and as a laboratory solvent. The common ways people expose themselves to methyl tert-butyl ether include drinking contaminated water. This VOC’s health repercussions are still being studied, but it usually leads to skin and eye irritation.
This VOC solvent is mostly used by dry cleaning companies to dissolve oils, greases, waxes, etc. without ruining the fabric. Perchloroethylene was the primary VOC found in Camp Lejeune’s waters, and it is still used in water repellents, sealants, glues, printing inks, etc.
In many cases, people are exposed to low levels of PCE. This should not cause any major health issues. However, those who wear dry-cleaned clothes are at a slightly higher risk.
If water storage tanks are contaminated with PCE and the situation remains undetected for years, it is a matter of grave concern. Just like the Camp Lejeune victims, one may develop conditions that threaten survival or adversely impact the quality of life.
This third type of waterborne VOC is usually released as a disinfection by-product. The disinfection process itself is a result of water treatment using organic matter. The CDC states that the levels and composition of trihalomethane depend upon the water treatment conditions and the type of disinfection process.
Most people are exposed to this VOC through the consumption of chlorinated water. Health risks associated with mild exposure are unclear. However, massive doses of trihalomethane can damage the central nervous system and cause hepatotoxicity.
The Activated Carbon Filtration Method of VOC Removal
One of the longstanding methods of removing VOCs from the water includes activated carbon filtration. It is important to remember that the success of water purification depends on the type of VOC.
For instance – vinyl chloride particles easily get trapped into the porous carbon filters. This happens due to the filter’s large surface area. If the filtration method succeeds, it removes all bad odors and tastes as well.
However, a major disadvantage is the short lifespan of an average activated carbon filter. Most will last between two and six months before they require replacement. Each filter’s maximum capacity depends upon its size and contaminants in the treated water.
Moreover, these filters may not be able to remove all VOC contaminants from the water (up to their last traces).
More Effective Purification Methods on the Horizon
Up until now, the process of VOC removal from water was marked by slow adsorption and high energy usage. However, new technologies are on the horizon that can remove microplastics and extremely small-sized VOCs due to a photothermal effect.
An atypical porous polymer has been discovered by researchers at South Korea’s Daegu Gyeongbuk Institute of Science and Technology (DGIST). The material exhibits VOC rejection at a rate of 98% and can remove around 99.9% of the pollutants.
The aim of producing this polymer is to tackle the growing problem of freshwater availability and to do so economically.
In the final analysis, it may take some time before a filtration membrane using the DGIST researchers’ polymer is developed. Gradually, the same should become accessible worldwide for water purification at commercial and residential levels.