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What Science Tells Us About Exercise Hydration

Analies Dyjak @ Thursday, September 14, 2017 at 2:12 am -0400

Mike Molloy, Ph.D.  |  Founder: M2 Performance Nutrition

Editor's Note: Dr. Molloy (pictured above) received his Ph.D. from Dartmouth Medical School. His R&D background and status as an elite athlete puts him in a unique position to come up with scientifically-backed nutritional strategies, as well as to experiment with emerging techniques that show promise.  Dr. Molloy's results speak for themselves... 10 of his elite clients competed in the most recent Reebok CrossFit Games.

Is Hydration As Simple As "Filling Up Big Bags Of Water?"

Everyone's probably heard the statement that we humans are just big bags of water, and that's fairly true with 50-60% of our total body mass being water. FYI, men are a little higher on that average and women are typically a little lower. No surprise, but water is extremely critical for pretty much all of the functions that occur in the body at a cellular and organ based level. Water in your body basically is divided into two major compartments; the intracellular fluid (inside the cell membrane) and extracellular fluid (outside of the cells), your blood fluid being a perfect example. While both ICF and ECF are still water, they're actually pretty different as it relates to electrolytes with ICF being higher in potassium and magnesium and ECF being higher in sodium and chloride.

What Are The Different Ways That We Get Water Into And Out Of Our Body?

IN: No shocker here, drinking water and water based products. However, most foods contain a solid water component as well, notably fruits, veggies and water cooked carbs like rice and oatmeal.

OUT: Breathing, evaporation from the skin, sweating, urination and feces (AKA going Number 1 and Number 2).

Should I Just Drink When I'm Thirsty?

One of the major questions that we get is whether you can trust your thirst level to judge when to drink more fluids. As is common in the nutrition world, the answer is "it depends." Most of the time, your body doesn't generate a "thirst" response until about 1.5% of water is lost. Now if you're inactive, thats not a huge deal, but from an athletic performance point of view, its huge. Add on top of that the individual response to exercise ("sweater" vs. "non sweater") and making generalized statements about this topic is extremely difficult.

What science-based recommendations can we make? The Institute for Medicine determined that an adequate intake for men is ~3 liters and ~2.2 liters for women. Of course, there's a bunch variables that could cause you to want to drink more (and sometimes less) than these amounts. Another approach is to use your urine color as an indicator of hydration. Aiming for a goal of "slightly yellow" with ~5-6 urinations through a day seems to be a helpful goal for most people. Of course, supplements that have yellow coloring such a multivitamins, B vitamins, tumeric, etc. can skew the urine color so just just aware of that when considering this approach.

As a performance based nutrition coach, I'm definitely interested in how dehydration can impact human performance. We do know that the 1-2% dehydrated state can have a fairly large impact on performance in both endurance and more strength based efforts. However, we also know that OVER-hydrating can have negative impacts on performance as well if hyponatremia (low blood sodium levels) occurs. In extreme cases, this can actually be life-threatening.

What Should I Drink During Exercise? 

Athletes should be drinking about 8-10 ounces of water 20-30 minutes prior to exercise with another 5-7 ounces for every 20-30 minutes of exercise that follows, in an ideal world. For longer efforts, adding some carbohydrates to the water can improve the absorption of water into the blood circulation, along with any electrolytes that are included as well. Interestingly, several amino acids are also capable of helping to improve hydration as well, notably glutamine, alanine cysteine and glycine. All that said, most research indicates that exercise sessions lasting an hour or less are not negatively impacted by simply drinking water.

Should I Be Mixing Supplements Into My Water?

There's only a few things that I think are worth giving a try. Remember, everyone's a little different so ultimately your response to these approaches will be different as well.

  1. Himalayan salt: There is some evidence to show that a small dose (a pinch?) of Himalayan salt can help remove some of the burden we place on the adrenal glands through our day to day stresses. I personally keep the dose small and just do it for a single glass of water in the morning.
  2. Magnesium citrate: You might be surprised to learn that ~75% of Americans are deficient for magnesium. This is important because studies show that low magnesium levels can impact testosterone production, increase blood pressure and also reduces the efficiency of neuromuscular firing. Dosing can range from 300-500 mgs for the average person.

Is There Any Benefit To "Alkalized" Or Alkaline Water?

There's a hypothesis that an acidic diet (from both food and water) will impact blood pH and cause disease. It's important to note that blood pH is an extremely tightly regulated process and ordinary food or water products simply cannot impact this process. Now, the theory actually states that acid foods cause the body to pull calcium out of the bones in order to maintain the normal blood pH. However, what we know from a 2009 meta-analysis is that there was no association between the body's calcium levels and urine calcium levels. What they did find was that if your FOOD has higher calcium levels, so will your urine... which makes logical sense. So just to recap, higher acidic foods do not appear to pull calcium from your bones. If you want to dive deeper into this topic, I'd suggest checking out this article.

If you'd like to learn more about hydration for athletes or connect with Dr. Molloy, you can visit M2 Performance Nutrition's Website, and follow them on Instagram.

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Perfluoroalkyl And Polyfluoroalkyl Substances (PFASs): What You Need To Know

Analies Dyjak @ Thursday, August 31, 2017 at 4:10 pm -0400

Stephanie Angione, Ph.D.

Updated 1/29/2020 to include new data.  

What Are Perfluoroalkyl and Polyfluoroalkyl Substances (PFASs)?

Fluorinated substances include a diverse range of chemical compounds that all contain at least one fluorine (F) atom. These substances vary in the amount of fluorine atoms they contain, and those that are highly fluorinated, or contain many F atoms per carbon (C) atom are referred to as perfluoroalkyl substances. These highly fluorinated substances are unique in their hydrophobic (water repellent) and lipophobic/oleophobic (fat/oil repellent) properties, as well as their general chemical and thermal stability.

These properties have made PFAS substances common in many types of applications, including creation of non-stick cooking surfaces, stain and water resistant coatings on fabrics, creation of oil/fat resistant food packaging and also in foam materials used to fight and prevent fires. Additionally, the automotive, aerospace, and construction industries have widely used these fluorinated substances for various applications due to their low friction properties.

Common PFASs include perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), which have been used in the production of Teflon and Scotchgard respectively. The manufacturer 3M phased out the production of PFOS in 2002 and the EPA helped manufacturers of PFOA phase out production completely in 2015.

How Do PFAS Substances Contaminate the Environment?

PFASs are deemed “emerging contaminates” by the EPA; meaning that they are chemicals or materials thought to pose a potential threat to health and the environment, but haven't yet been regulated. PFASs contribute to environmental contamination largely due to the fact that they are highly resistant to degradation processes, and thus persist for many years in water, air and can enter the food chain via bioaccumulation in certain animal species.

The primary sources of human exposure to PFAS include:

  • Consumption of contaminated drinking water
  • Consumption of food that is packaged in materials containing PFASs, which have included fast food containers, microwave popcorn bags. (Most food manufactures have stopped using PFASs in these types of packaging.)
  • Consumption of food that contains PFASs, including fish and shellfish
  • Contact (hand to mouth) with clothing, carpets or other fabrics that have been treated with PFASs. (Skin exposure to PFASs on their own does not cause significant absorption into the body.)

What Are the Health Effects of PFAS?

The discovery of persistent contamination of drinking water sources with PFOA in West Virginia and Ohio prompted a large epidemiological study called the C8 Health Project. The study included nearly 70,000 individuals who had elevated PFOA levels in blood – approximately 500% higher than the representative population. The study found statistical correlation between elevated blood concentrations of PFOA with ulcerative colitis, impaired thyroid function, high blood cholesterol, testicular cancer, kidney cancer and preeclampsia.

How Do Polyfluoroalkyl & Perfluoroalkyl Substances Contaminate Drinking Water?

In 2016 the EPA released a lifetime health advisory for PFOA and PFOS in drinking water. This advisory indicates that the individual or combined concentration of PFOA and PFOS in water should be less than 70 parts per trillion (ppt). This EPA guideline is not an enforced limit – it simply provides guidance to local public health officials. However, under EPA guidelines issued in 2012, water systems are required to monitor levels of PFOA and PFOS. The results of this monitoring effort can be found on the National Contaminant Occurrence Database. Together with data collected under the monitoring effort and established assessments of human health effects, the EPA will make a regulatory determination to include PFOA and PFOS in national drinking water regulations.

Communities that have sources of drinking water contaminated with PFASs are typically localized and associated with a specific industrial facility or area used for firefighting. Both PFOA and PFOS have been found in drinking water systems due to this kind of localized contamination. A 2016 study of drinking water in the U.S. found unsafe levels of PFASs at the EPA minimum level of 70 ppt in 194 out of 4,864 water sources in 33 states. More recently, a 2020 study has shown that PFAS contamination is more widespread than originally thought.  Water sources with the highest levels of PFAS contamination were near industrial sites and military bases, and one of the major contributing sources was found to be firefighting foam.

How Can I Remove Polyfluoroalkyl & Perfluoroalkyl Substances From My Drinking Water?

Some public water systems employ methods (like granulated or powdered activated carbon) to reduce PFOA and PFOS at the municipal level, but these systems do not remove shorter-chain PFAS, like GenX. Hydroviv water filters use a blend of highly-porous active media including carbon, specialized ceramics, and ion exchange media to provide broad protection against PFASs (short and long chain) from drinking water (3rd party test reports for Hydroviv products can be Viewed HERE and HERE) . Water filtration systems that use reverse osmosis systems can also be effective, but you'll want to contact the manufacturer and ask for 3rd party test results against PFAS (not just PFOA/PFOS, which are easy to filter).  

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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Arsenic In Drinking Water: Exposure, Toxicity, Removal By Water Filters

Christina Liu @ Tuesday, August 15, 2017 at 11:10 pm -0400

We do everything from providing in-depth breakdowns of common contaminants to reports on city tap water quality. We’re keeping it going by writing about another common heavy metal that can contaminate drinking water: Arsenic.

How Are We Exposed To Arsenic?

Humans are exposed to inorganic arsenic mainly through contaminated drinking water. Some water sources in the United States have higher naturally occurring levels of inorganic arsenic than other regions. Levels of inorganic arsenic in soil typically range from 1-40mg/kg and the EPA recommended concentration in water supplies is less than 10µg/L. However, higher levels can occur near natural mineral deposits, mining sites, smelting industries, and regions where pesticides have been applied.

In addition, workers who use arsenic compounds for smelting, pesticide manufacturing and application, and wood preservation are at a higher risk for arsenic poisoning.

Below is a map published by the United States Geological Survey (USGS) which shows the concentration of arsenic in groundwater in the United States. It’s estimated that 2 million Americans have private wells and drink water with unsafe levels of Arsenic. If you live in one of the areas with high arsenic concentration, and get your drinking water from a private well, we highly recommend getting your water tested by a qualified laboratory

arsenic in well water

Source: https://www.usgs.gov/mission-areas/water-resources/science/arsenic-and-drinking-water?qt-science_center_objects=0#qt-science_center_objects.

Arsenic Toxicity

Arsenic is a toxic heavy metal several epidemiological studies have reported a strong association between arsenic exposure, cancer, and systemic diseases. In fact, arsenic exposure affects virtually all organ systems including the cardiovascular, dermatologic, nervous, hepatic, renal, gastrointestinal, and respiratory systems. The severity of the adverse health effects is related to both the chemical form of arsenic and the dosage. Evidence of carcinogenicity due to arsenic exposure is very strong, but the specific mechanism by which it causes cancer is not completely understood.

Recent studies have found that pregnant women are especially susceptible to the harmful effects of arsenic exposure. Arsenic exposure can drastically impact reproductive outcomes, affect fetal development, and can lead to long term health problems. However, the association between chronic arsenic exposure and adverse pregnancy outcomes is not widely recognized.

What Can I Do To Reduce My Exposure To Arsenic?

A growing number of people are realizing that regulatory limits are not always in line with current toxicological studies, and are taking steps to minimize exposure to heavy metals like arsenic, lead, mercury, and chromium 6 from their drinking water, even if their city is "in compliance" with EPA regulations.

Unlike lead, which leaches into water from pipes, arsenic comes from the source water itself, so flushing pipes or replacing plumbing will not reduce arsenic concentrations. Boiling water also does NOT remove arsenic. Arsenic must be removed using a water filter that is specifically designed to do so.

Whole House Filters

While some whole house filters can reduce arsenic levels to some extent, we don't recommend most whole house water filters due to their high cost and unnecessary filtration of water when it isn't consumed (such as flushing the toilet). Instead, we advocate for point-of-use water filters, which are more efficient and cost-effective for filtering water that is being consumed. 

In cases where arsenic levels are very high and exceed our performance specifications, we may suggest considering a specialized arsenic removal filter at your home's point of entry to bring the levels within our operating parameters. Once this is achieved, you can use a Hydroviv filter at your point of use for further arsenic reduction.

Point Of Use Water Filters For Arsenic

The most cost-effective method of arsenic, chromium 6, and contaminants filtration is through a point of use water filter. When shopping for these systems, we encourage you to make sure that the filter actually filters arsenic (most don't). While we believe that our advanced under sink filters have unique benefits and use filtration media that effectively remove both types of inorganic arsenic, some systems that use reverse osmosis can be a good choice for people who are willing to accept the downsides. No matter what... make sure that your filter removes what you think it does!

As always, feel free to take advantage of our “help no matter what” approach to technical support! While we do make water filters that remove arsenic, our water nerds are happy to answer your questions about the effects of arsenic in water, even if you have no intention of purchasing a Hydroviv Water Filter. Reach out by dropping us an email (hello@hydroviv.com) or through the live chat on our webpage.

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EPA Superfund Sites: An Overview on Hazards and the Process

Analies Dyjak @ Monday, August 7, 2017 at 6:00 pm -0400

Emma Schultz, M.S.  |  Scientific Contributor
Updated 12/1/2023 to include latest numbers of Superfund sites by state. 

Do you know where your nearest EPA Superfund Site is? Chances are there is one close by, given that one out of every five Americans lives within three miles of an EPA-designated major hazardous waste site. There are two sites located within four miles of my childhood home, in an idyllic and quiet suburb of St. Paul, Minnesota. I now live within the same distance of five sites -- and I had no clue. 

Superfund Sites - Environmental Hazards

What does it mean to be living so close to so much waste? Common contaminants found at EPA Superfund Sites include asbestos, lead, radiation, and dioxins; these all pose significant risks to human and environmental health. In addition, hazardous substances can leach into the soil from ground level or contaminated water, and can then migrate into nearby homes through subsurface intrusion, entering buildings through foundation cracks and sewer lines. This vapor intrusion then poses further risk to nearby residents, inside of their homes where they would otherwise be inclined to feel safe. Obviously, proximity to a Superfund site is critical; four miles' distance poses a decreased health risk as compared to a mere forty feet.

What Is The Superfund Process?

The concept of EPA Superfund Sites is widely known and understood, but the intricacies of the program and the approach to hazardous waste mitigation are elaborate and prolonged, as can be expected of any federally-funded long-term project.

History: 

In December of 1980, President Jimmy Carter signed into law the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), now known better as Superfund, which authorized the EPA to remediate hazardous waste spills and sites, and obliged those responsible for the waste - the Potential Responsible Party - to either clean it up on their own dollar or offset the cost of EPA-led cleanup efforts. Superfund had abundant funding early in its existence due to taxes levied on chemicals and oil; those taxes, however, lapsed in 1995, and financing now comes from taxpayers.

Process and Stages:

There are multiple stages in the Superfund process once a site is identified, with the first step being a Preliminary Assessment or Site Inspection. If the site is an emergency such as a chemical spill, Removal Action is taken. Otherwise, Remedial Action is planned for, which often leads to years-long planning, cleanup, and remediation. Community involvement is frequently key during the early stages of Superfund designation, and the Technical Assistance Services for Communities (TASC) program is an outreach effort designed to connect with citizens and businesses for the duration of a Superfund's existence.

After initial study, EPA Superfund Sites are given a score on the Hazard Ranking System. If a site poses enough of a threat to environmental and human health, the EPA announces its addition to the National Priorities List (NPL), pending public comment and input. NPL sites are eligible for extensive, and often long-term, federal funding through the Superfund program. These NPL-listed sites are now officially Superfund sites.

Following NPL designation, a Remedial Investigation and Feasibility Study is conducted. The Remedial Investigation collects information on-site such as water and soil samples, and the follow-up Feasibility Study analyzes various cleanup methods. The EPA then selects the most suitable cleanup alternative and provides it to the community as a Proposed Plan.

A Record of Decision notes the cleanup alternative chosen for the site. In the Remedial Design phase, the cleanup plans are drawn up, and are finally acted upon in the Remedial Action stage. A goal of Remedial Action is to return sites to productive use as quickly as possible. Whether 'productive' means industrial, housing, commercial, or greenspace depends on conversations and input from the surrounding community.

A review of EPA Superfund Site cleanup efforts occurs every five years. If cleanup goals have all been met, a portion or whole of a Superfund site may then be listed for removal from the NPL. In theory, meeting all cleanup goals sounds achievable - especially given the lengthy planning and implementation phases - but there are many sites that remain listed decades later, because groundwater and soil are still polluted.

Where Can You Learn More About Superfund Sites?

Finding out if there are Superfund sites near your home is the first step that all concerned citizens should take. There are 10 Regional Superfund Community Involvement Offices around the country that exist to take your questions and concerns regarding existing or potential Superfund sites. 

Here is the latest list of states and the number of Superfund sites they contain. Be aware that not all toxic contaminants are on the list for contaminated sites to qualify for Superfund. For example, PFAS contaminated sites are not yet regulated under CERCLA. 
States With Superfund Sites

Resources for homeowners:

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Polychlorinated Biphenyls (PCBs): Everything You Need To Know

Analies Dyjak @ Saturday, August 5, 2017 at 3:56 pm -0400

Stephanie Angione, Ph.D.  |  Scientific Contributor

What Are Polychlorinated Biphenyls (PCBs)?

Polychlorinated Biphenyls (PCBs) are a class of industrial chemical that were widely manufactured in the US from the 1930s through the 1970s for use in electric equipment such as capacitors and transformers, and also as heat transfer fluids, plasticizers, adhesives, fire retardants, inks, lubricants, cutting oils, pesticide extenders, and in carbonless copy paper.
 
While PCB production slowed in the 1960s and was banned completely in the US in 1979, they are still found in industrial applications due to their chemical longevity. The US congressional ban was enacted due to the fact that PCBs are persistent organic pollutants, which create long lasting environmental toxicity and cause harmful health effects. Products that contain PCBs include old fluorescent lighting fixtures, PCB capacitors in old electrical appliances (pre-1978) and certain hydraulic fluids.
 
Nearly 2 million tons of PCBs have been produced since 1929, 10% of which persists in the environment today. Generally, environmental concentrations of PCBs are low, but due to their chemical inertness they are largely resistant to chemical breakdown or thermal destruction, and thus accumulate in the environment. Additionally, PCBs are highly fat soluble, resulting in the build up of PCBs in animal fat, resulting in higher concentrations of PCBs in top food chain consumers (e.g. predatory fish, large mammals, humans).
 

Where Are PCBs Found In The Environment?

Polychlorinated Biphenyls accumulate primarily in water sources, organic portions of surface soil, and in living organisms.
 

Water

Surface water that is contaminated with PCB waste generally has high levels of PCBs in sediment, as the PCBs attach to organic matter. PCBs can be slowly released from the sediment into the water and evaporate into the air, especially at higher temperatures.

Air

PCBs have been detected throughout the atmosphere, and can be transported globally through air. Concentrations of PCBs in the air are generally the lowest in rural areas and highest in large cites. Areas that are close to bodies of water that were highly contaminated with PCBs from industrial waste (e.g. Lake Michigan, Hudson River) can have higher air concentrations, due to evaporation of PCBs into the air over time.  


Living Organisms

PCBs accumulate in living organisms via bioaccumulation, or uptake from the environment, as well as biomagnification, from consumption along the food chain. Bioaccumulation is typically highest in aquatic species, with bottom feeding species having the highest levels of PCBs due to accumulation in sediment.  PCBs biomagnify up the food chain, as bottom feeders like shellfish are eaten by other species, and thus the greatest levels are found in large predatory fish. This process can also occur on land, as PCB contamination in soil is transferred up the food chain to insects, birds and mammals. Thus, one of the largest sources of PCB exposure and accumulation in humans is from food, specifically meat and fish.

How Do PCBs Impact Humans?

While PCBs have been classified as probable human carcinogens, there is no evidence that the low levels of PCBs in the environment cause cancer. Exposure to high levels of PCBs have primarily occurred through workplace exposure in people who work in plants that manufacture the chemicals. Studies of workers exposed to high PCB levels have shown association with certain types of cancer. These high levels of exposure have also been known to cause liver damage, skin lesions called chloracne, and respiratory problems.

Exposure to PCBs during pregnancy can result in developmental and behavioral deficits in newborns. Additionally, there is evidence that reproductive function can be disrupted due to PCB exposure. Women of childbearing age, or those who are pregnant or nursing should be aware of fish and shellfish advisories to limit consumption of PCB contaminated fish.
There are additional studies that suggest PCB exposure can cause health effects including thyroid dysfunction, liver dysfunction, as well as adverse cardiovascular, gastrointestinal, immune, musculoskeletal, and neurological effects.

How Are PCBs Regulated & Monitored In The US?

With so many sources of PCB exposure from food and water sources, the US government has guidelines on the amount of allowable environmental PCB contamination for each.  

Food

The FDA enforces a tolerance level in fish of 2 ppm, and overall 0.2 -3.0 ppm for all foods. PCBs in paper food packaging are limited to 10 ppm.
 
If fishing recreationally and you plan to eat your catch, check if any local fish consumption guidelines exist for your area. The EPA maintains a national database of fish and shellfish advisories issued by each state. These consumption advisories may recommend limiting the amount of a certain fish consumed, or from specific waters or water sources. As of 2011, five areas have advisories for PCBs in freshwater sources (Missouri, Minnesota, Maryland, Indiana, and District of Columbia) and nine states (Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, and Rhode Island) have PCB advisories for coastal waters.

Drinking Water

Under the Clean Water Act, industrial discharge of Polychlorinated Biphenyls in water is prohibited. The goal is to reach zero contamination in drinking water, but the enforceable maximum level is 0.0005 part per million (ppm).  Additionally, industries are required to report spills or accidental releases to the EPA. 

Routine monitoring of PCB levels in drinking water require the water supplier to maintain the limit enforced by the EPA and must make the data regarding water quality and contaminants public. Every year, the EPA requires water suppliers nationwide to provide a Consumer Confidence Report (CCR), which will include information about water treatment and any known contaminants. These reports are available on the EPA website and should be available on your water company’s website. Additionally, the supplier is required to alert customers of increased levels of PCB contamination as soon as possible.
 
If you get water from a household well, the local health department should have information about ground water quality and contaminants of concern, but it is often a good idea to have your water tested by a certified laboratory if you are worried about PCB (or other) contaminants. The EPA’s Safe Drinking Water Hotline (800-426-4791) can provide additional resources in your local area.

How Can I Remove PCBs From My Water?

If your water has high levels of PCBs in it,  the water should also not be used to drink, prepare or cook food,  or given to pets for consumption without first treating it.  Fortunately, PCBs are effectively removed from water by filters that use activated carbon as part of their active filtration media blend.
 
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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