Water Quality Articles | Written By Actual Experts – Hydroviv

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GenX Contamination In Drinking Water:  What You Need To Know

GenX Contamination In Drinking Water: What You Need To Know

Eric Roy, Ph.D.  |  Scientific Founder

****Updated November 18, 2017 to include water filter performance data ****

There has been some major news coverage about "GenX" and other pre GenX perfluoroalkyl chemicals contamination in North Carolina.  Whenever something like this makes it into the news, the facts can quickly become obscured, so the aim of this article is to summarize a few key things to know about GenX and other perfluoroalkyl chemicals in drinking water.

What Is GenX?

GenX chemical structure Chemours

GenX is a trade name for a chemical (deduced structure shown above) that went into production around 2010 as an alternative to a perfluorooctanoic acid (also known as PFOA or C8) in the synthesis of  PTFE (ie Teflon).  GenX is therefore essential for the production of common household products including non-stick pans, firefighting foam, and common outdoor fabrics (e.g. Gore-Tex).

Why Do We Care About GenX And Chemicals Like It?

It's pretty simple:  1.  These chemicals are known to be toxic (and this link too)  2.  They are persistent in the environment, which means that they don't break down, and can contaminate water far from the contamination source.

Is GenX Regulated By EPA?

No.  Which means that there are no regulatory limits, and municipalities are not required to test for it.  There are a lot of chemicals that fall into this category.

Why Is This Such A Big Problem In North Carolina?

A company called Chemours (which was originally spun out of Dupont) produces GenX at a plant in Fayetteville, NC.  Discharge from this plant contaminates the Cape Fear watershed.  

What Are Official Positions On The Situation?

Dupont:  In summary, they are saying that even though Chemours is a Dupont spinoff company, they have no comment because it's now a separate entity.

Chemours:  Lips are largely sealed right now

Municipalities in Southeast North Carolina:  "We are in full compliance of Federal Regulations"

Hydroviv:  No kidding.  You can't be out of compliance if it's not a regulated chemical.

How To Remove Or Filter GenX And Other Fluoroalkyl Compounds From Drinking Water

At Hydroviv, we custom-build water filters using different technology than reverse osmosis.  Basically, we custom-formulate filter cartridges with filtration media that best matches the problems in each customer's water.  There's a lot of proprietary stuff behind what we do, but in the name of transparency we wanted to give more information that we'd normally give about what we are doing to formulate filters for highly soluble compounds like GenX.

1.  We formulate our submicron carbon blocks with a blend of activated carbons and elevated levels of a highly porous metal oxide sorbant blend that other fluoroalkyl compounds have been shown to stick to in the scientific literature. 

2.  We tighten up the pore sizes of our filters, which slows down the flow and increases the amount of time that the water is in contact with the filtration media, thus improving the overall effectiveness of the filter, when compared to granular or powdered media.

**** Update 11/18/2017**** Our under sink and fridge line water filters have been independently tested by researchers at North Carolina State University and both filters have been shown to remove GenX to undetectable levels.  

Filters with these considerations can be ordered through our product's page, and our experts will automatically use your shipping address to know if you are part of the impacted region.  

We recommend that people take advantage of our "Help no matter what" approach to technical support.  We have been staffing our live chat line through extended hours to answer questions that people may have.  If our chat line is busy, you can drop us an email at hello@hydroviv.com.  We will answer as soon as we can.

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Please Stop Using TDS Testers To Evaluate Water Quality

Please Stop Using TDS Testers To Evaluate Water Quality

Eric Roy, Ph.D.  |  Scientific Founder

We get quite a few questions about TDS meters and TDS measurements.  While we love when people take steps to learn more about their water, some people (including journalists from reputable publications- Example #1  Example #2) have used TDS meters to draw false conclusions about water quality, which incited fear in people already in the midst of a terrible water quality crisis.  In this article, we answer the questions that we get asked the most about TDS measurements and TDS meters.

What is TDS?  What Does A TDS Meter Measure? 

TDS stands for Total Dissolved Solids which is related to the total charged mineral content of water.  TDS can be easily determined by measuring the conductivity of a water sample, which is exactly what inexpensive TDS probes do.  If you start with deionized water (which has a TDS of zero), and expose it to minerals that contain sodium, calcium, and magnesium ... the water's TDS rises.  This is why there's no such thing as deionized water in nature.  Depending on a region’s geology, natural TDS levels can vary across the US, and this variability has nothing to do with the water quality (except in extreme cases when the water is too salty to drink).

What Does a TDS Meter Not Measure?

Because TDS is an aggregate measure of charged compounds in water, uncharged things like motor oil, gasoline, many pharmaceuticals, and pesticides do not contribute to a TDS measurement.  For example, the glass on the left in this article's header image contains deionized water with Malathion (an organophosphate pesticide) dissolved into it at 100 times higher concentration than allowed by the EPA for drinking water, and the TDS probe reads 000.

What About Lead, Arsenic or Chromium 6?

Even though these toxic metals are charged when dissolved in water, a TDS meter does not give meaningful information about their presence or concentration in water.  There are two main reasons for this:  

  • A TDS meter is a nonselective measurement and cannot differentiate among different ions.  A more sophisticated piece of equipment is needed to perform those types of measurements.  The value of 184 that was measured using an inexpensive TDS meter in a prominent Huffington Post Article was not the lead concentration… it was the TDS level (which is dominated by minerals like calcium, magnesium, and sodium) of the tap water.
  • A TDS meter is not sensitive enough to measure toxic levels of lead, chromium-6 or arsenic, even if they are present in a sample. This is because the reading displayed on an inexpensive TDS meter is in parts per million, while lead chromium-6, and arsenic are toxic at part per billion concentrations (1000 times lower). Using a TDS meter to measure ppb lead concentrations in tap water is like trying to use a car’s odometer to measure a child's growth spurt…. It's the wrong tool.  For example, the water sample shown on the right hand side of this article's header image has lead concentrations 100x the EPA limit, and the TDS reading teetered between 000 and 001.  

To reiterate:  Meaningful lead and arsenic measurements cannot be made using a TDS meter (or any other handheld device).  They must be measured by trained staff in analytical laboratories that use much more sophisticated scientific equipment.

Do Hydroviv Filters Lower TDS?

No.  Hydroviv’s filters selectively filter harmful things from your water (like lead, chromium-6, pesticides, pharmaceuticals, petroleum products, disinfection byproducts), and things that make water taste and smell bad (chlorine, chloramine, sulfur).  Hydroviv’s water filters don’t remove minerals like calcium and magnesium because there’s no reason to.  In fact, we use some types of filtration media that actually add minerals to the water, so TDS levels in water filtered through a Hydroviv system are sometimes slightly higher than unfiltered water.

Should I Buy a TDS Meter To Test My Water For High TDS Levels?

No. There is absolutely no reason to drink low TDS or deionized water.  If you are concerned about water quality, put the money toward the purchase of an effective drinking water filter that removes harmful contaminants from your water.

What If I Already Have a TDS Meter?

If you have a TDS meter, we recommend giving it to a curious child who has an interest in science!  Use the opportunity to teach them about dissolved minerals by encouraging them to test different types of water (e.g. distilled, rain, river, lake) and try to explain their findings!   Feel free to reach out to us at (info@hydroviv.com for educational ideas involving TDS meters). 

If you mail it to us, we’ll make sure it finds a good home in a school classroom, and we’ll send you a $20 coupon code to use on Hydroviv's website.

Other Great Articles That We Think You'll Enjoy:

How EPA Regulations For Lead Are Protecting Municipalities, Not Citizens

What Science Says About Fluoride In Tap Water

Does New York City's Tap Water Have a Lead Problem?

Does New York City's Tap Water Have a Lead Problem?

New York City’s Tap Water New York City provides municipal tap water for more than half the population of New York through an impressive network of 19 reservoirs and 3 lakes. Even though New York City’s tap water is widely recognized in the water industry as the “Gold Standard” for urban water providers (it’s truly an engineering feat on an unimaginable scale), the older infrastructure (pipes, plumbing, service lines) found in New York City itself presents a risk of lead contamination once the water reaches the city’s distribution system. This risk is higher for older building (where pre 1986 plumbing is found) and in multi level complexes, because water accumulates lead while it sits in pipes. 

 Compiled Lead Test Results New York City Tap Water

​(EPA Action Level = 15 ppb)

Lead In New York City Tap Water

This table shows compiled data (aggregated from city reports) for water samples collected from customers’ faucets during the years 2007 through 2015. In all years, a meaningful percentage of the samples tested for lead were above the 15 ppb threshold set by US EPA, with some samples being recorded at upwards of 400 times that. It’s important to point out that despite the high lead levels, 2010 was the only year where NYC was in violation of EPA’s Lead and Copper Rule, because it was the only year where more than 10% of samples exceeded the 15 ppb threshold.  While the levels seen in the other years are in compliance with federal regulations, the EPA, CDC, and World Health Organization all agree that there is no such thing as a safe amount of lead exposure for children.

How To Minimize Lead Exposure If You Live In New York City:

If residents don't use a water filter that removes lead, there are ways to minimize exposure:

  • Allow water to run for at least 2 minutes before collecting water for consumption (drinking/cooking).   Doing so allows the water that is sitting in the pipes to flush out and be replaced by fresh water flowing through the large mains.  
  • Only run the faucet at a moderate rate when collecting water for consumption.  Doing so minimizes the amount of lead particulates that can be swept into the water stream.
  • Regularly remove the aerator grid on the faucet to keep lead-containing particles from building up and releasing lead into flowing water.
  • Never drink or cook using water from the hot water faucet.  

Hydroviv strongly advises NYC residents to take advantage of the free lead testing program if they choose not to filter their water.  Under this program, people can request a free kit to test for lead in their drinking water by calling New York City’s 24-hour helpline at 311 or visiting www.nyc.gov/apps/311.

As always, we encourage you to take advantage of Hydroviv's "Help No Matter What" technical support policy, where we answer questions related to drinking water and water filtration, even if you have no desire to purchase our products.  Drop us a line at support@hydroviv.com

Other Great Articles That We Think You'll Enjoy:

How EPA Regulations For Lead Are Protecting Municipalities, Not Citizens

What Science Says About Fluoride In Tap Water

Why Are So Many Schools Testing Positive For Lead In Drinking Water?

Why Are So Many Schools Testing Positive For Lead In Drinking Water?

Eric Roy, Ph.D.  |  Scientific Founder  

***Modified on November 7 to update links and add additional cities ***

With more schools in major cities testing positive for lead contamination (e.g. New York CityCleveland, Chicago, Portland, Newark, San Francisco), we get lots of questions about what’s happening.  The goal of this article is to shed some light on why lead contamination in schools is such an important thing.

Children Are Most Sensitive To Lead Poisoning

There is no level of lead that is known to be safe for children.  Period. 

Since lead contamination in tap water entered the spotlight in 2015, people have incorrectly presented EPA's regulatory limits as safe/not safe thresholds.  While a simple safe/unsafe threshold would certainly make things more simple, the 15 ppb threshold was never intended to be a "safe level."  It’s a limit that EPA established to evaluate city-wide corrosion control practices and it allows a city to have up to 10% of samples test ABOVE the 15 ppb threshold, and still be in compliance with the Lead and Copper Rule.  For reference, the American Academy of Pediatrics is calling for regulatory changes that ensure that water never tests above 1 ppb in schools.

Most Schools Are Old & Old Plumbing Often Contains Lead

According to data assembled by the U.S. Department of Education, the average age of a Public School building in the United States is 44 years old, a time when lead-based plumbing was the norm.  Even in newer schools, lead contamination can creep into water because lead wasn’t completely phased out of plumbing connections, fittings, and valves until 2014.

Weekends & Summers Allow Water To Sit Stagnant For Extended Periods Of Time In Schools

As many now realize, lead accumulates in water when it leaches from lead-containing pipes, valves, and plumbing connections.  The longer water sits stagnant in pipes, the more lead it can accumulate.  Unlike in homes, where water is used on a daily basis and never sits stagnant for more than a few hours each night, water in schools goes completely unused for long periods of time each weekend, vacation, and summer.  These frequent long periods where water is not used are detrimental for two reasons: 

1.  Lead has more time to accumulate as water sits stagnant in lead-containing pipes

2.  The lack of flushing prevents corrosion measures from rebuilding the protective layer that prevents lead from leaching out in the first place. 

Most Schools Do Not Test Water Properly For Lead Contamination

It sounds crazy, but most schools don’t test for lead contamination in water.  When asked by a reporter about testing the school’s water for lead, an elementary school superintendent went on record to say that "We do not test because it has never been brought up as a concern, nor is it a requirement to do so."

The reality is, even if schools choose to test for lead contamination, it’s much more complicated than testing in a residential home.  In a residential home, EPA sampling protocols require that water be unused for 6 hours, in order to simulate the night and work day periods where water commonly sits stagnant in pipes.  However, this protocol does not mimic how water is used in schools, because in addition to the 12 hours each school night the water goes unused, it sits stagnant for roughly 60 hours each weekend, and much longer periods over school vacations and summer.  

How Can Schools Reduce Lead Contamination In Drinking Water?

Realistically, it’s probably cost-prohibitive for schools to replace all lead-containing plumbing or buy and maintain effective point of use drinking water filters that remove lead.  When school administrators approach us for solutions, we always advise them to take immediate steps to identify lead containing plumbing, test their water for lead, and to implement regular pipe flushing protocols.

We encourage everyone to call their city's school department to better understand if and how lead is being tested for in schools.  Because testing in schools is very complicated, we encourage people to ask for specifics of the testing program and actual results, not blanket assurances that everything is ok.   As always, we encourage all readers to take advantage of our “Help No Matter What” approach to technical support.  Technical support will answer your questions through email (support@hydroviv.com), free of charge, even if you have no plans to purchase a Hydroviv water filter.

Originally published on January 28, 2017.  Updated May 9, 2017

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Does New York City Tap Water Have A Lead Contamination Problem?
Pittsburgh's Lead Level Exceeds EPA Limits In 2016
Why You Are Being Mislead By Your TDS Meter

How Mining Activities From Long Ago Continue To Pollute Water Today

How Mining Activities From Long Ago Continue To Pollute Water Today

Daphne Abrams M.S.Ed.  |  Scientific Contributor   

I became interested in the impact of mining a few years ago when I started teaching an environmental science class in northwestern Nevada.  Nevada has a rich history of pioneers and mining (It is the silver state after all).  While mining can be a source of revenue and prosperity for an area, it also has a huge environmental impact that can last many decades after the mining activity ends. This article discusses how this has played out in the Carson River.

Historical Mining Activities And EPA Superfund Sites

EPA’s Superfund program is responsible for cleaning up highly contaminated land and responding to environmental emergencies, oil spills and natural disasters in order to minimize long-lasting contamination from these events.  Even though the government has categorized these sites as highly toxic, they are sorely underfunded when it comes to cleanup and often forgotten about altogether.  This is particularly problematic because one in six Americans live within 3 miles of a Superfund site. The closest two Superfund sites to the school that I teach at are two abandoned mining sites. One is the Carson River Mercury Site, which is the legacy of silver and gold mining in the area, and the other is from the abandoned Rio Tinto Copper Mine. 

Lasting Impacts Of Historical Mining Activity On The Carson River

Between the contamination from these two Superfund sites, roughly eighty miles of the Carson River is paralyzed by heavy metal toxicity.  Even though contamination likely occurred in the 1800s, there are still advisories not eat fish caught in that stretch of the Carson River, due to concerns about mercury, which biomagnifies up food the food chain. 

What's Being Done About Contamination From Historical Mining Activities?

While it seems hard to debate against cleaning up these types of historical toxic messes,   the Senate and House voted to overturn the “Stream Protection Rule” shortly after President Trump took office, as part of the new administration's campaign promise to relax environmental regulations.  

Do You Have More Questions About How Historical Mining Activities Contaminate Drinking Water?

Hydroviv makes it our business to help you better understand your water. As always, feel free to take advantage of our “help no matter what” approach to technical support! Our water nerds will work to answer your questions, even if you have no intention of purchasing one of our water filters. Reach out by dropping us an email (hello@hydroviv.com) or through our live chat. You can also find us on Twitter or Facebook!

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Organophosphate Pesticides:  What You Need To Know

Organophosphate Pesticides: What You Need To Know

Stephanie Angione, Ph.D. | Scientific Contributor

Pesticides are chemicals used to kill environmental pests including insects, weeds, fungi and rodents. This article focues on organophosphate pesticides, which are one type of pestides used today.  If you're looking for a more general overview on pesticides, you can view it here.

History Of Organophosphate Pesticides

Organophosphate pesticides largely replaced DDT and other chlorinated hydrocarbons in the 1960s and 1970s, including the compounds malathion, parathion, and diazinon. These compounds were originally favored over DDT since they break down much more rapidly in the environment, and do not present the problem of persistent pollution like their predecessors.  That said, the degradation products of organophsophate pesticides can also be toxic.  The EPA has thus banned the residential use of organophosphates, but they are still widely used in agricultural applications and for mosquito abatement. Organophosphate pesticides account for approximately 30-40% of all insecticides used in the US.  Despite their widespread use and toxicity, organophosphate pesticides break down in the environment rapidly, and are thus rarely found as contaminates in groundwater as the intact chemical, but 

Health Effects Of Organophsphate Pesticide Exposure

The health effects of organophosphate pesticides in humans differ based on acute or chronic exposure, as well as the exposure amount. Since organophosphates inhibit the action of acetylcholinesterase, acetylcholine builds up in the nerves, and overstimulation of the central nervous system results in widespread effects including headache, seizures, depression of respiration and circulation, tremors and potentially coma. Victims of acute organophosphate poisoning typically die because they can’t breathe. Effects of chronic exposure are similar and include confusion, memory loss, depression, disorientation, weakness, headache, nausea and vomiting. While still inconclusive, there is evidence that organophosphate exposure causes several types of cancer, including lymphoma and leukemia.

How Do I Remove Pesticides From Drinking Water?

Water filtration systems that use activated carbon as part of the filtration media blend or reverse osmosis can be effective in removing pesticides from water.  Contrary to what some people tell you, boiling/freezing waterdoes NOT remove pesticides from drinking water!

Do You Have More Questions About Organophosphate Pesticides In Drinking Water?

Hydroviv makes it our business to help you better understand your water. As always, feel free to take advantage of our “help no matter what” approach to technical support! Our water nerds will work to answer your questions, even if you have no intention of purchasing one of our water filters. Reach out by dropping us an email (hello@hydroviv.com) or through our live chat. You can also find us on Twitter or Facebook!

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