Water Quality InformationWritten By Actual Experts

Michelle Scire  |  Scientific Contributor

What Is 1,2,3 Trichloropropane And Where Does It Come From?

1,2,3 Trichloropropane (TCP) is a synthetic chemical that is commonly used as an industrial solvent, cleaning and degreasing agent, and paint and varnish remover.  In California’s Central Valley, widespread TCP contamination was caused by a now-banned fumigant DBCP, which was used to kill nematodes (small worms that live in the soil). When applied to the soil, TCP leaches from the deeper soil to groundwater. When DBCP was banned in 1977 by the EPA, it was commonly used on over 40 crops in California. Unfortunately, TCP is persistent in the environment, and as of November 2017, 395 of the 5863 wells used by public water supplies had levels of TCP that exceeded the California regulatory limit. When looking at a map of contaminated wells (above), you will see a strip right up the center of California from south of Bakersfield to Sacramento with some prominent outliers in Los Angeles, San Diego, Salinas, San Jose, San Francisco, and Chico counties. 

Why Do We Care About TCP?

TCP is some nasty stuff. In the short-term, high levels of inhalation exposure to TCP can cause irritation of eyes, respiratory tract and skin, and has the ability to depress the central nervous system. Moreover, studies in rodents have confirmed it may affect memory, focus and muscle coordination. Long term exposure studies have found exposure in rodents can lead to liver and kidney damage as well as reduced body weight and tumor growth. To get an idea of how toxic TCP is, the 5 part per trillion MCL (legal limit) is equivalent to a single drop of water being diluted into about 5.5 olympic sized swimming pools!.

Timeline of Public Knowledge Related To TCP Toxicity

Data from: HERE

What Took Regulation Of TCP So Long?

While it’d be great if regulatory bodies were able to act quickly, the reality is that regulations take time, often decades to execute. In the case of TCP specifically, Cindy Forbes, the deputy director for Californiawater board’s drinking water program, insists that TCP regulation was a “top priority,” but explained that they had limited resources preventing them from reaching“the finish line.” In California, the process to establish a maximum contaminant level (ie regulatory limit) includes: conducting their own peer-reviewed research, evaluating cost of detection and cleanup, as well as allowing public comment (which undoubtedly includes comments from companies responsible for contamination). Forbes claims, “It’s my priority, it’s the board’s priority,” but one has to wonder what the word priority means when there is scientific research going back 25 years explicitly showing the repercussions of this contaminant. There is only one carcinogen with a lower state public health goal for drinking water, and that is dioxin.

What Can Be Done To Treat Water That Has Been Contaminated With TCP?

Large Scale TCP Remediation Techniques

Because of the contamination primarily leaching into the ground water in California's Central Valley, ground water remediation methods have been established. TCP can be removed with traditional methods such as, “pump and treat granular activated carbon filters (GAC), in-situ oxidation, permeable reactive barriers (zero-valent zinc), dechlorination by hydrogen-releasing compounds, and emerging biodegradation techniques.” A new method was developed recently using, “in-line, pressurized advanced oxidation process (HiPOx) that has the ability to remove TCP from groundwater to below 0.005 μg/L.” The treatment techniquewill depend on the level of contamination in groundwater or soil being treated. While these methods are indeed effective, they are expensive and require long planning/execution periods.

Small Scale (Residential) TCP Removal of TCP

If your home’s water is contaminated with TCP, and large-scale treatment isn’t happening in an acceptable time frame, some residential water filters do remove TCP. Our advice is to find a water filter that is advertised to remove volatile organic compounds (VOCs), and ask the manufacturer for a data sheet that shows effective removal of TCP specifically. 

If you have any more questions about 1,2,3 Trichloropropane contamination, we encourage you to reach out to our “Help No Matter What” technical support through live chat or email (hello@hydroviv.com). Our Water Nerds are happy to answer any questions you may have!

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Hydroviv's Science Team

Most people are aware of Volatile Organic Chemicals (VOCs) because they are frequently discussed when selecting paint for their home, but many people don't realize that they can contaminate drinking water supplies. This article provides a broad overview of VOCs as it pertains to water, and also gives practical advice on how to protect against them if a water supply becomes contaminated.

What Are Volatile Organic Chemicals (VOCs)?

By definition, VOCs are a class of chemicals that vaporize easily at normal air temperatures. VOCs are commonly found in household and industrial products including gasoline, solvents, cleaners and degreasers, paints, inks and dyes, and pesticides. For example, gasoline is a mixture of VOCs including benzene, toluene, and other hydrocarbons, which gives gasoline it’s familiar odor.

Can VOCs Contaminate Drinking Water?

Absolutely. In fact, the US Geological Survey (USGS) found in a recent study that VOCs are present in one-fifth of the nation's water supplies. For example, benzene, (a constituent of gasoline) commonly enters groundwater when it spills or leaks out of underground fuel tanks. Other examples of commonly detected VOCs in drinking water include dichloromethane (methylene chloride), an industrial solvent; trichloroethylene, used in septic system cleaners; and tetrachloroethylene (perchloroethylene), used in the dry-cleaning industry.

How Are VOCs In Drinking Water Regulated By EPA?

Because It would be impractical and costly for municipalities to test for every potential chemical that can be categorized as a VOC, EPA regulates a subset of chemicals that commonly contaminate water supplies. For example, benzene, one rather common constituent, is regulated with a maximum contaminant level set at 0.005 milligrams per liter (parts per million) and a goal of zero in drinking water. Water analysis can be requested if there is reason to suspect the presence of a specific VOC.

Private wells are not covered by EPA's regulations and testing is typically optional. While VOCs can be detected by odor at high concentrations, laboratory analysis is the only way to measure VOCs in drinking water at the regulatory limits. We highly recommend that all people who get water from private wells get their water tested by an accredited laboratory.

How To Remove VOCs From Drinking Water

High quality water filters are the only effective way to remove Volatile Organic Compounds in water. These water filter companies (including Hydroviv) test their filters against chemicals that are selected to represent a wide range of VOCs that commonly contaminate water supplies. The NSF Standard 53 protocol for VOC reduction requires manufacturers to test against the chemicals listed in the table below:

Table 1: List of chemicals that are part of the NSF 53 Standard Test For VOC Reduction

As always, we encourage you to reach out to our “Help No Matter What” technical support through live chat or email (support@hydroviv.com). Our team will provide science-backed advice on water quality and water filtration, even if you have no intention of buying a Hydroviv water filter.