In a modern, industrialized first-world country, the simple act of turning on a faucet and filling a glass, a pitcher, or a pot with water isn’t an action that typically comes with a lot of analysis. For most, it’s like a second-nature process: You need water, you get water, and you move on. However, all across America – as with many other first-world nations – water contamination is becoming an increasingly problematic issue. Ever heard of hexavalent chromium? Well, there’s a good chance that you’re at least familiar with the film, Erin Brockovich, which catapulted it into mainstream awareness. Whereas the movie is a Hollywood depiction of a single contamination that took place in Hinkley, California, contamination of groundwater with hexavalent chromium is something that’s become more of a news staple, rather than a box office dramatization.
What’s the Issue Here?
The big question surrounding this issue is, of course, why is this a serious problem? What’s up with hexavalent chromium? For starters, it’s extremely toxic. When inhaled – something most likely to happen in the case of industrial workers – it can inevitably lead to lung cancer and other respiratory ailments. When it reaches groundwater sources and is subsequently ingested, it can lead to a variety of cancers – most commonly stomach and gastrointestinal cancers – as well as ulcers, kidney and liver failure, and more. Children are particularly susceptible to the effects of hexavalent chromium, putting them at much higher risk for developing any of these medical conditions due to exposure to the toxin.
So now you’re probably wondering, who’s even using this stuff in the first place? Well, plenty of industrial plants, for one. Hexavalent chromium is commonly used as an anti-corrosion agent, usually in industrial cooling systems. Industrial and manufacturing facilities often rely on a heat exchanger system or cooling towers that circulate water through a system of pipes in order to draw heat away from machinery and equipment. The water alone can lead to corrosion over time, especially if it happens to be slightly more acidic, but various chemicals are often added to the water in order to enhance the cooling process or to help break down mineral and bacterial buildups in the system, something that can also add to the corrosive property of the water. The hexavalent chromium is therefore added in order to undermine any corrosive properties found in the water.
Other industrial practices create or use chromium due to completely different processes. It’s a common feature in various leather tanning enterprises, as well as welding industries, textiles (dyes), and wood preservation. Whether as an additive or as a by-product, hexavalent chromium pops up in all of these industries and, if not handled properly, can easily find its water in groundwater supplies. This is precisely why it’s important for heat exchanger systems to be regularly cleaned and repaired, and for professionals to be consulted in order to find other options besides hexavalent chromium that can help combat corrosion.
Contamination and Clean Up:
Hinkley, California, isn’t the only city in America where hexavalent chromium has been found in drinking water. At least 31 cities across the country have been shown to contain the toxic chemical, but the EPA hasn’t taken action because the levels are well below their maximum limit of 100 ppb (parts per billion). The issue with that cutoff number is that it measures total chromium content, which includes other chromium chemicals that aren’t a health risk to people. California has seen the most research and experimentation done regarding hexavalent chromium, with scientists deciding that anywhere from .02 ppb to .07 ppb would be the maximum acceptable values for human consumption.
Groundwater contamination continues to be a problem across the country, with plumes of the chemical spreading throughout aquifers, and therefore polluting more and more drinking water. Various sites in California have popped up, as well as in New Mexico, Texas, Massachusetts, and Illinois, among others. Groundwater contamination is extremely hard to combat though, as once chemicals and toxins enter an aquifer it’s difficult to stop them from flowing through it. Clean up processes include pumping up groundwater and treating it in order to remove the toxins, or added non-harmful substances to the groundwater meant to interact with the toxins and cause them to break down into non-harmful elements.
A major stumbling block, however, are the limits being set for how much hexavalent chromium is allowed in drinking water? With the EPA yet to set a clear mandate specifically regarding hexavalent chromium, it’s likely that carcinogenic levels of the toxic chemical will remain in the drinking water of many communities. Reliable supplies of freshwater are crucial for both residential and agricultural use, and, unless further change can be enacted regarding the safety of groundwater, we’re likely to see further problems down the road.