Water Quality InformationWritten By Actual Experts

Eric Roy, Ph.D. 

A new report was released which confirmed that an outbreak of Legionnaires' disease in Flint, Michigan that killed 12 people and sickened at least 87 during 2014 and 2015 was likely caused by low chlorine levels in the municipal water system. It's another example of Flint's broader water crisis that resulted from widespread incompetence and fraud. We will add to this article as more questions come in.

What Is Legionnaires' Disease?

Legionnaires is a pneumonia, caused the bacterium Legionella pneumophila. Legionella pneumophila grows in water, and can enter the lungs through tiny water droplets. If a person doesn't have a robust immune system, they can become very sick, or even die.

Where Is Legionella Found?

According to Marc Edwards (A professor at Virginia Tech), Legionella is found in about 25 percent of all water samples collected nationally. It's a common bacterium, but it's usually kept under control in municipal water.

How Is Legionella Typically Controlled In Municipal Tap Water

In properly treated municipal water, Legionella is kept under control by chlorine-based disinfectants, so the bacterium cannot reach dangerous levels. In Flint, it appears that not enough chlorine was added to the water to leave enough residual chlorine to keep the bacterium under control, which is what caused the Legionnaires' outbreak in Flint.

Is Flint Still At Risk Of Legionnaires Disease?

According to Edwards, chlorine in Flint's water is now at the correct level, so the likelihood of Legionnaires' disease popping back up is minimal. It is our opinion at Hydroviv that concerned Flint residents should take every piece of advice issued by Dr. Edwards. If he says that there is enough chlorine, there is enough chlorine.

How Are Chloramine and Chlorine Different?

We answer this question in much more detail in a different post, but here's the skinny on chlorine in drinking water: Like a growing number of US cities, Washington, DC uses chloramine as the primary disinfectant for a couple of reasons:

1. It persists longer in the distribution system, so it does a better job killing bacteria in areas of the water distribution system that are near the end of the pipes, or don't have as high of flow as other areas.
2. It doesn't form disinfection by products in the presence of organic matter.
3. Chloramine-treated water doesn't have as strong of a taste as chlorine-treated water

While these are all great reasons to use chloramine, most cities that use chloramine undergo a more aggressive disinfection cycle for a few weeks each year (aka Spring Cleaning).

What Are The Impacts of Switching to Chlorine?

During this time, some people find that the water tastes and smells tastes bad, and the bathroom smells a bit like a swimming pool's locker room after showering. If you want to fix this problem... you have a couple of options that don't involve bottled water (horrible for the environment).

1. Filter your water 
2. If you let chlorinated tap water sit in a pitcher overnight, a good amount of the chlorine taste will go away.

When Will Washington, DC's Water Switch Back Over to Chloramine?

May 17, 2021 is the day that DC Water plans to switch back over to chloramine. Until then... non-Hydroviv users will just have to hold their noses!

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Eric Roy, Ph.D.  |  Scientific Founder

***Updated to include 2021 water quality data***

For Hydroviv’s assessment of Washington, D.C. drinking water, we aggregated water quality test data from D.C. Water (the public utility provider) and the U.S. Environmental Protection Agency (EPA), as well as from samples that we collect and analyze. We cross reference these data with toxicity studies in the scientific and medical literature, and look at upcoming regulatory changes. The custom water filters that build and sell for Washington, D.C. are optimized with these factors in mind.

Lead In DC Tap Water

Washington, D.C. is an old city with a lot of lead service lines, so it's not a huge surprise that D.C. has had such a big problem with lead in drinking water. Lead leaches from lead-containing pipes, solder, and fittings, unlike most contaminants which are found at the source. D.C. Water uses two sampling periods when testing for lead: January-June and July-December. In the 107 samples pulled during January-June period, the 90th percentile concentration for lead was 2 parts per billion, and 3 samples were above the 15 part per billion Action Level (AL). In the 105 samples pulled from the July-December sampling period, the 90th percentile concentration was 3 parts per billion, and one of the collected samples exceeded the action level. Although these results indicate that D.C. is in citywide compliance with federal water quality standards, it's important to point out that EPA, CDC and the American Academy of Pediatrics all agree that there is no safe level of lead for children. The bottom line is that the federal standards allow up to 10% of sampled taps to have lead concentrations over 15 parts per billion.

We highly recommend that Washington D.C. residents take a look at this map to see if their home has a lead service line, because those homes (and homes with plumbing that predates 1986) are most susceptible. We also highly recommend taking advantage of D.C. Water's free lead testing program, and any families with small children take steps to remove any lead from their water, even if they don't use a Hydroviv filter. It's important to remember that most pitchers and fridge filters do NOT remove lead from water. Hydroviv Undersink filters are NSF/ANSI 53 certified to remove lead from drinking water.

Detectable Levels of Unregulated Contaminants In DC Tap Water

One thing that has caused quite a bit of alarm from several people in this year's report is that several herbicides, VOC's and synthetic compounds were all found at detectable levels in D.C. drinking water. Herbicides such as Dalapon, shouldn't be a huge surprise seeing that D.C. draws water from near at the end of a river, so there is opportunity for agricultural runoff to enter the river. For anyone who is interested, The Maryland DEP has made the Source Water Assessment for the Potomac River (404 pages) publicly available. 

DC's Water Source: Potomac River

The Washington Aqueduct (operated by the Army Corps of Engineers) draws water from the Potomac River for treatment. District of Columbia Sewer and Water Authority (aka D.C. Water) purchases treated water from the Washington Aqueduct, and is responsible for distributing it throughout D.C. We also have a stand-alone article that entirely focuses on the Potomac River.

Left Out Of The Report: Chromium 6

We were a bit surprised to see Chromium 6 left out of the 2019 water quality report for Washington, D.C. Even though it's a known human carcinogen, chromium 6 is categorized as an "Emerging Contaminant" by EPA but is not regulated on its own. D.C. Water (and 6000 other municipalities) participate in the Unregulated Contaminant Monitoring Rule (UCMR3), which is a nationwide testing program to study "emerging" contaminants. UCMR acknowledges that contaminants on the list most likely cause adverse health effects, including cancer. The concentration in D.C. water average 86 parts per trillion. For perspective, these levels are roughly 4-5x higher than what The State Of California set as a public health goal. We believe that people should not wait for EPA to begin regulating chromium 6 on its own, and filter their water, even it they aren't using our product. It's important to remember that most pitchers and fridge filters do NOT remove chromium 6 from water.

Per and Polyfluoralkyl Substances (PFAS) In Washington, D.C. Drinking Water

PFAS are a category of chemicals found in various non-stick/stain resistant products, as well as fire fighting foam. PFAS are considered to be "emerging contaminants" because they are not currently regulated by EPA, but are known to be toxic and persistent in the environment. PFAS have been detected at surrounding military installments that are in close proximity to the Potomac River (DC's source water). Most municipalities are not required to test for, or remove, PFAS from drinking water. Not all filters are designed to remove PFAS from drinking water. If you'd like find water filters that remove PFAS from tap water, check out this Duke/NC State study.

Disinfectant

The primary disinfectant used to treat Washington DC's tap water is chloramine, except for a few weeks in the spring when DC switches over to chlorine. D.C. (and a growing number of municipalities) use chloramine instead of chlorine for a few reasons: for one, chloramine is more persistent than chlorine, so it maintains its ability to disinfect the water further away from the source. On the other side, chloramine does not quickly dissipate from water if left in a jug overnight. If you want to get it out of the water, you'll need a filter designed to remove chloramine, because a regular charcoal filter doesn't do a great job removing it.

If you want to learn more about Hydroviv's water filters, check out www.hydroviv.com, or drop us a line through live chat or email (hello@hydroviv.com). Even though we sell our products nationwide, Hydroviv is a DC company and we take care of our own backyard!

As always, feel free to take advantage of our "Help No Matter What" approach to technical support. We will answer your questions about water quality even if you have no desire to purchase one of our products. 

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By Brendan Elmore

While most people talk about chlorinated tap water, a growing number of municipalities are implementing an alternative disinfectant - chloramine – in place of chlorine. This article on chloramine vs. chlorine discusses the advantages and disadvantages of both disinfectants, why municipalities are switching to chloramine, and what this means from a water filtration standpoint.

Chlorine: The Original Method For Tap Water Disinfection

Chlorine was the original disinfectant used in US municipalities, with Jersey City being the first city to implement a chlorine-based system in 1908. Still today, chlorine remains the primary disinfectant in the majority of municipalities in the US, because of its effectiveness and low cost. While tap water disinfection using chlorine has a long track record, there are two major downsides to using chlorine as a disinfectant altogether.

1. Chlorine is volatile and can escape from tap water as it travels through water mains, which can eliminate the “chlorine residual.” Without residual chlorine, water becomes more susceptible to microbial growth.
2. Chlorine can react with naturally-occurring organic compounds, creating what are known as disinfection by-products (DBPs) which are associated with kidney and liver problems.

Chloramine: A 'New' Alternative to Chlorine

1. Chloramine is less volatile than chlorine, so it stays in the water longer than chlorine, which ensures that all areas of the distribution network are properly disinfected.
2. As the EPA began to learn about the toxicity of DBPs, they began searching for an alternative disinfectant for chlorine. Chloramine is less reactive with naturally-occurring organic matter, so it produces lesser amounts of DBPs. 

Despite these advantages, chloramine isn’t without its own shortcomings. For example, when a municipality switches over to a chloramine-based system to comply with DBP regulations, the level of pipe corrosion inhibitor needs to be increased, because chloramine-treated water is more corrosive than chlorine-treated water. Washington, DC did not properly do this when they switched over to a chloramine-based disinfection system in the early 2000s, and the city underwent a 5-year lead contamination crisis where more than 42,000 children under the age of 2 were exposed to high levels of lead, putting them under great health risk.

Even when pipe corrosion is properly accounted for, chloramine must be removed from the water when it is being used for dialysis, aquariums, baking, and even craft brewing (maybe you didn't burn your mash after all!).
 

What Can I Do to Remove Chlorine & Chloramine From My Tap Water?

Removing chlorine and chloramine from water involve different methods.

Fortunately, chlorine is very easy to remove from tap water to improve the taste. For example, if you fill a water jug and leave it in your fridge uncapped, within a day or two, the chlorine will volatilize and go away.Common filtration pitchers, refrigerator pitchers, and under sink filtration systems are also good for removing chlorine from water and the bad taste associated with it.

Chloramine, on the other hand is much harder to filter, and most “big name” water filters are not designed to remove it. A special type of activated carbon, called catalytic carbon, is the best tool for removing chloramine from water. High-quality custom water filters that use catalytic carbon in their filter formulation also offer broad protection against other contaminants in drinking water.

If you have any questions about chlorine or chloramine, we encourage you to take advantage of Hydroviv’s “Help No Matter What” approach to technical support, even if you have no desire to purchase a Hydroviv system. This free service can be reached by emailing support@hydroviv.com, or by using the live chat window.

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Article Sources
https://www.scientificamerican.com/article/how-does-chlorine-added-t/
http://www.caslab.com/News/testing-for-trihalomethanes-in-your-water-tthm.html
http://www.chloramine.org/chloraminefacts.htm
https://www.washingtonpost.com/local/dcs-decade-old-problem-of-lead-in-water-gets-new-attention-during-flint-crisis/2016/03/17/79f8d476-ec64-11e5-b0fd-073d5930a7b7_story.html
Technical Memorandum No. MERL-2013-57 Effect of Chlorine vs. Chloramine Treatment Techniques on Materials Degradation in Reclamation Infrastructure

Disinfection byproducts are a class of contaminants that have been detected in drinking water throughout the country. Unlike things like arsenic and lead, most people are not familiar with disinfection byproducts. The goal of this article is to dive deep into the chemistry, history and policy surrounding disinfection byproducts.

What Are Disinfection Byproducts?

Water disinfection was an extremely successful public health accomplishment. It's the main reason why waterborne illnesses are not a persistent threat in United States tap water. However, adding chlorine-based disinfectants to water can have harmful unintended consequences, one of which being that they can react with other things found in tap water (e.g. organic matter) and form a class of halogenated chemicals known as "disinfection byproducts." Disinfection byproducts are generally regarded as an "emerging contaminant", because despite having identified more than 600 different disinfection byproducts, roughly 50% are still unaccounted for.

Why Do We Care About Disinfection Byproducts?​

Many halogenated organic compounds are known carcinogens in humans (e.g. dioxin, DDT, Carbon Tetrachloride, PCBs), so they rightfully receive quite a bit of scrutiny when detected in tap water. While some disinfection byproducts in water have almost no toxicity, others have been associated with cancer, reproductive problems, and developmental issues in laboratory animals. Some population-scale epidemiology studies have also found an association between chlorinated tap water and these same problems in humans. Because more than 200 million people in the US use chlorinated tap water as the primary drinking water source, it’s something worth taking a very close look at.

How Are Disinfection Byproducts Regulated?

History Of Disinfection Byproduct Regulation

In 1974, trihalomethanes were detected in drinking water and linked to chlorine based disinfectants that were added to municipal tap water. Around the same time, the National Cancer Institute classified trihalomethanes as human carcinogens, and as a result, EPA established a drinking water standard for trihalomethanes in 1979. As more was learned about disinfection byproducts in water, the US EPA and other government, public health, and industry stakeholders began negotiating 2 stages of more comprehensive regulations in the mid-1990s. Stage 1, which was published in 1998 for 2002 compliance, ruled that haloacetic acids must also be monitored in tap water, in addition to trihalomethanes. The Stage 1 Rule also mandated that these chemicals be monitored throughout the entire water distribution system, not just a few predefined sampling locations. The results of the increased monitoring revealed that more municipalities were non-compliant than initially expected. Stage 2 of the regulation was published in 2006 (for 2012-2016 compliance), and further refined the sample collection strategy with the goal of protecting the public. In the future, most people expect that the regulations will continue to tighten as more about the long term effects of these chemicals becomes better understood, and the technologies that reduce their concentrations at the municipal level improve.

 

Chemical structures of the 4 most common trihalomethanes: Chloroform, Bromodichloromethane, Dibromochloromethane, and Bromoform

 

Chemical structures of the 5 regulated haloacetic acids: Chloroacetic acid, Dichloroacetic acid, Trichloroacetic acid, Bromoacetic acid, Dibromoacetic acid

How To Know If A Municipality's Tap Water Has High Levels of Disinfection Byproducts

Overall, disinfectant byproduct concentrations are difficult to predict, because many factors influence their formation including: concentration of organic matter, chemical composition of the precursor materials, pH, temperature, type of disinfectant used, and the concentration of disinfectant. However, because monitoring for trihalomethanes and haloacetic acids are mandated by the EPA, the average concentrations found in the water supply must be made available to the public in annual drinking water reports. 
​
Within a given municipal water system, different physical locations can have higher disinfection byproduct concentrations than others, based on where the home or business is located. This is because the longer it takes for the water to reach the home, the more opportunity there is for disinfection byproducts to form. Therefore, locations close to fast flowing water mains often have lower levels of disinfection byproducts than homes found at the periphery and low flow areas of the water distribution network. Additionally, disinfection byproduct concentrations can continue to rise in residential pipes/water tanks if the water remains stagnant for extended periods of time (e.g. during the work day, overnight). In fact, most municipalities recommend letting water run for 1-10 minutes before using it for drinking or cooking so pipes can flush out. (Obviously, nobody does this….)

What Are The Primary Ways That People Are Exposed To Disinfection Byproducts In The Home?

​In the home, most people primarily use chlorinated tap water to drink, bathe, wash dishes, etc. A few studies have looked at the relative importance of the various exposure pathways, and found that showering contributed heavily to blood levels of trihalomethanes. While this may be initially surprising, it does make sense, because trihalomethanes can be volatilized in hot water and subsequently inhaled. During a shower, disinfection byproducts can also enter the body through absorption through the skin. Because most people come in contact with over 17 gallons of water in an “average” 8 minute shower, but drink less than a half-gallon of water each day, it makes sense that showering can be a major exposure path. Granted, this study only looked at the exposure route for one class of disinfection byproducts, but it does reveal that exposure pathways in addition to drinking, and is a great discovery to build upon with follow-up studies. 

What Can Individuals Do To Reduce Their Exposure To Disinfection Byproducts?

​To be clear, the discovery of DBP exposure through showering does NOT mean that you should be afraid of showering, rather it's a piece of information that may be considered in any changes to the regulation. As frustrating as it may be to people "looking for answers," the reality is... good science is a slow process... and modifications to regulations are often even slower! While regulatory agencies and municipalities are taking steps toward reducing DBPs in water (by pre-oxidizing or filtering out organic precursors), the most effective way for consumers to reduce their exposure today is by filtering their water at the point of use, and/or by flushing stagnant water out of the pipes by letting it run for a few minutes before using it.

Sources:

1. https://www.epa.gov/ (and sources therein)  Accessed on 12/25/2015
2. https://www.cdc.gov/safewater/publications_pages/thm.pdf
3. Backer, LC, et al., 2000
4. Richardson et al., 2007

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