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Most Tap Water Is a Toxic Soup of Chemicals

Mercola, J. (2020, March 11). Most Tap Water Is a Toxic Soup of Chemicals. Mercola.


  • Tap water is often brimming with harmful pesticides, herbicides, pharmaceuticals, cyanobacteria, disinfection byproducts, and fluoride
  • Cyanobacteria from algae can cause skin irritations, neurological symptoms, and liver and kidney damage and are linked to diseases like Alzheimer's and amyotrophic lateral sclerosis (ALS)
  • The herbicide glyphosate worsens toxic algae because cyanobacteria use its phosphonates as fuel
  • Concentrated animal feeding operations (CAFOs) and large-scale monocrop farms cause high levels of nitrates to be in drinking water
  • PFAS, found in a wide range of consumer products, are also in tap water and can accumulate and stay in the human body for long periods of time

Discussion of the safety of tap water often only occurs when an immediate threat is identified like the lead crisis in Flint, Michigan,1 and ongoing Legionella outbreaks.2 But the state of U.S. tap water, whether from wells or municipal water systems, is very concerning even when it is not in the news. Just because tap water looks clear and seems to taste normal does not mean it is safe or pure. It is often brimming with pesticides, herbicides, pharmaceuticals, cyanobacteria, disinfection byproducts (DPBs), and fluoride, but few realize these harmful agents are in the water they are drinking.

Results from tests conducted by the Environmental Working Group (EWG) from 2010 to 2015 on 50,000 water utilities in 50 states found 500 different contaminants.3 How many people would drink the tap water if a label disclosed such contaminants?

"Our research shows that the nation’s water supply is under assault from a toxic stew of pollutants," wrote EWG.4 The toxins include "fluorinated chemicals called PFAS, lead from old pipes, runoff from farmland that carries millions of tons of pesticides and fertilizer chemicals into rivers and streams," wrote EWG.

Toxins From Algal Blooms in Drinking Water

You may be aware of harmful algal blooms that are caused by manure, sewage and fertilizer runoff. These algae overgrowths can contain toxins like the cyanobacteria microcystis5 and the cyanobacteria metabolite BMAA,6 yet the toxicity of the blooms can't be determined from the way they look or smell.

Microcystis can cause skin irritations, neurological symptoms, and liver and kidney damage in humans and even harm pets.7 BMAA is suspected of causing neurological diseases like Alzheimer's, Parkinson's, and amyotrophic lateral sclerosis (ALS).8 In the journal PLOS One, researchers studying the effect of BMAA on dolphins wrote:9

"Dietary exposure to BMAA is associated with the occurrence of neurofibrillary tangles and β-amyloid plaques in nonhuman primates. The findings of protein-bound BMAA in brain tissues from patients with Alzheimer’s disease has advanced the hypothesis that BMAA may be linked to dementia …

We observed increased numbers of β-amyloid+ plaques and dystrophic neurites in the auditory cortex [of dolphins] compared to the visual cortex and brainstem. The presence of BMAA and neuropathological changes in the stranded dolphin brain may help to further our understanding of cyanotoxin exposure and its potential impact on human health."

Exposure to algal toxins can come from contact with the water or algae, breathing airborne toxins, eating contaminated fish and shellfish10 and drinking contaminated water.11 Algae overgrowth also has tremendous environmental implications. The density of blue-green algae blocks light and can deplete oxygen in the water, leading to huge dead zones and fish kills. The U.S.'s largest dead zone is located at the mouth of the Mississippi River and measures nearly an astounding 9,000 square miles, equivalent to the size of New Jersey.12

Drinking Water Dangers Heightened by Glyphosate

Researchers are now identifying another driver of harmful algal bloom: glyphosate, the active ingredient in Roundup herbicide. Scientists originally did not think that plankton, which include cyanobacteria, could use phosphonates like glyphosate as fuel.

But Bowling Green State University professors R. Michael McKay and George Bullerjahn determined that cyanobacteria do access phosphonates as fuel.13 This is what the professors wrote about their findings:14

"Our research is finding that Roundup is getting into the watershed at peak farming application times, particularly in the spring … It turns out that many cyanobacteria present in Lake Erie have the genes allowing the uptake of phosphonates, and these cyanobacteria can grow using glyphosate and other phosphonates as a sole source of phosphorus."

The professors' findings were buttressed by the subsequent research of Christopher Spiese, an Ohio Northern University chemist. According to Sustainable Pulse:15

" … Spiese took soil samples all over the Maumee watershed, applied P [phosphorus] to them and then sprayed glyphosate to see how much P was released vs. soil that wasn’t sprayed with glyphosate after 24 hours. Based on the average two glyphosate applications growers make every year, Spiese estimates that overall, 20-25% of the DRP [dissolved reactive phosphorus] runoff is caused by glyphosate."

Scientists writing in PLOS One also found that glyphosate was used as a fuel by some cyanobacteria species:16

"We studied the physiological effects of glyphosate on fourteen species representing five major coastal phytoplankton phyla. Group I could utilize glyphosate as sole P [phosphorus]-source to support growth in axenic culture … Glyphosate consistently enhanced growth of Group III …

We conclude that glyphosate could be used as P-source by some species while is toxic to some other species and yet has no effects on others. The observed differential effects suggest that the continued use of glyphosate and increasing concentration of this herbicide in the coastal waters will likely exert significant impact on coastal marine phytoplankton."

Glyphosate's contribution to algal toxins and contaminated drinking water adds to the already known harms of this controversial herbicide.

Other Farming-Related Causes of Contaminated Tap Water

Algal toxins, boosted by glyphosate, are not the only toxins found in tap water because of irresponsible farming practices. Concentrated animal feeding operations (CAFOs) and large-scale monocrop farms contribute to high levels of nitrates found in drinking water. Exposure to nitrates can cause blue baby syndrome, cancer,17 childhood diabetes mellitus,18 reproductive problems,19 disruption of thyroid function, and birth defects in humans.20

A recent opinion piece by two professors of public health in the Des Moines Register conveyed the enormity of the nitrate and drinking water problem:21

"Largely because of 23 million hogs, Iowa now has a 'Fecal Equivalent Population' of 168 million people … Over-application of manure, too often on frozen ground … increases in Iowa’s stream nitrate loads … our water leads all states in discharged nutrient loads …

Iowa has by far the most CAFOs of any state. We should heed the American Public Health Association’s Governing Council’s call in November 2019 for a national moratorium on new or expanded CAFOs, citing their 'threat to air quality, drinking water and human health' and to 'stop using medically important antibiotics in healthy animals.'"

Seventy percent of the world's water is now monopolized by agriculture. CAFOs and large-scale monocrop farms also deplete aquifers of valuable drinking water.

Other Causes of Contaminated Tap Water

Another group of harmful chemicals in drinking water are PFAS (per- and polyfluoroalkyl substances), which include PFOA (perfluorinated carboxylic acid) and PFOS (Perfluorooctanesulfonic acid). According to the EPA:22

"PFAS are found in a wide range of consumer products that people use daily such as cookware, pizza boxes and stain repellants. Most people have been exposed to PFAS. Certain PFAS can accumulate and stay in the human body for long periods of time. There is evidence that exposure to PFAS can lead to adverse health outcomes in humans …

Studies indicate that PFOA and PFOS can cause reproductive and developmental, liver and kidney, and immunological effects in laboratory animals. Both chemicals have caused tumors in animals. The most consistent findings are increased cholesterol levels among exposed populations."

PFAS are especially found in drinking water that is near affected landfills, wastewater treatment plants, manufacturers who use PFAS, and firefighter training facilities, says the EPA.23 PFAS have been dubbed "forever chemicals" because they build up in the blood and organs and resist degradation.24

According to Children's Health Defense, PFAS levels in tap water have increased significantly since the late 1980s in the U.S. and "widespread PFAS infiltration of community water supplies and private wells around the world" is now seen, even in remote areas.25 Adverse outcomes from PFASs are most concerning in children and may include:26

Lower birth weight and birth size Lower IQ and increased risk for learning disorders
Effects on levels of sex hormones and insulin-like growth factor 1, both of which play a critical role in growth and sexual maturation Increased risk of overweight and obesity
Dysregulated glucose metabolism Increased risk and severity of liver disease
Lower bone mineral density

More Chemical Dangers in Tap Water

Cyanobacteria, nitrates, lead, fluoride, and PFAS are just a few of the chemicals lurking in tap water. Also present are chemicals like carcinogenic volatile organic compounds (VOCs) and hexavalent chromium, says research in the journal Heliyon, taking a tremendous toll on U.S. health:27

"Cumulative risk analysis of contaminant occurrence in United States drinking water for the period of 2010–2017 indicates that over 100,000 lifetime cancer cases could be due to carcinogenic chemicals in tap water.

The majority of this risk is due to the presence of arsenic, disinfection byproducts, and radioactive contaminants … Overall, the national attributable risk due to tap water contaminants is approximately … two orders of magnitude higher than the de minimus cancer risk of one-in-a-million. Thus, decreasing the levels of chemical contaminants in drinking water represents an important opportunity for protecting public health."

Chemicals that may not be harmful by themselves may interact with other chemicals, hypothesize the authors:28

"[C]ontaminant mixtures may exert their toxicological effects in ways that differ from the simple response additive framework used in the present study. If mixtures of carcinogenic contaminants in water were to elicit a synergistic, or “greater-than-additive” toxicity effect, the overall risk would be greater."

Other risks present in tap water include the bacterium Legionella, mercury from "silver" fillings, disinfection byproducts like trihalomethanes (THMs) and haloacetic acids (HAAs), pharmaceuticals flushed down the toilet and from urine and feces and endocrine-disrupting personal care products.

Water Filtration Infrastructure Is Part of the Problem

When it comes to tap water pollution, glyphosate may do more harm than increase algae-related cyanobacteria. Research indicates the herbicide, which was originally patented as a descaling agent,29 can also chelate the lead out of pipes and transfer it into the water people drink. Old worn-out pipes can also deposit copper into tap water.

Pharmaceutical drugs, including the antibiotics so widely used in CAFOs, are also a tap water risk. It is a misconception that water filtration and treatment plants remove pharmaceutical drugs from tap water, according to a 2011 Harvard Health Letter:30

"Sewage treatment plants are not currently designed to remove pharmaceuticals from water. Nor are the facilities that treat water to make it drinkable … there's really not much question that some pharmaceutical pollution persists and does wind up in the water we drink."

Mary Buzby, director of environmental technology for Merck, agrees:31

"There’s no doubt about it, pharmaceuticals are being detected in the environment and there is genuine concern that these compounds, in the small concentrations that they’re at, could be causing impacts to human health or to aquatic organisms."

Homes Should Have Water Filtration Systems

Your safest bet against the risk of toxins and contaminants in your tap water is to install a quality water filtration system in your home. There are a variety of options, most of which have both benefits and drawbacks. Ideally, you want a filtration system that uses a combination of methods to remove contaminants, as this will ensure the removal of the widest variety of unwanted chemicals and substances. Below are a few of the most common filtration options.

  • Reverse osmosis (RO) —In addition to removing chlorine, inorganic and organic contaminants in your water, RO will also remove about 80% of fluoride and most DPBs. Drawbacks of RO include the need for frequent cleaning to avoid bacterial growth. Your best alternative is to use a tankless RO system with a compressor.

Cost is another consideration since you may need the help of a plumber to get the system operative. Note that in addition to removing harmful contaminants, RO will also remove many minerals and trace elements that might be valuable or desirable.

  • Ion exchange —Ion exchange is designed to remove dissolved salts in the water, such as calcium. This system also softens the water and helps prevent the creation of scale buildup.

While advantages of ion exchange include a high flow rate and low maintenance cost, disadvantages can include calcium sulfate fouling, iron fouling, adsorption of organic matter, organic contamination from the resin, bacterial contamination and chlorine contamination.32

  • Granular carbon and carbon block filters —These are the most common types of countertop and undercounter water filters. Granular activated carbon is recognized by the EPA as the best available technology for the removal of organic chemicals like herbicides, pesticides and industrial chemicals.

One of the downsides to granular carbon filters is that the loose material can "channel" — the water creates pathways through the carbon material and escapes filtering. Carbon block filters offer the same superior filtering ability but are compressed with the carbon medium in a solid form. This eliminates channeling and gives the ability to precisely combine multiple media in a sub-micron alter cartridge. By combining different media, the ability to selectively remove a wide range of contaminants can be achieved.

With the shocking breadth of chemicals that are now found in tap water, a home filtration system is a wise investment. It’s also important to continue opposition to glyphosate, CAFOs, and monocrop farms and products and manufacturers that pollute the environment with PFAS.