Fish on Prozac Prove Anxious, Antisocial, Aggressive

By Brian Bienkowski and Environmental Health News

New research has found that the pharmaceuticals, which are frequently showing up in U.S. streams, can alter genes responsible for building fish brains and controlling their behavior.

When fish swim in waters tainted with antidepressant drugs, they become anxious, anti-social and sometimes even homicidal.

New research has found that the pharmaceuticals, which are frequently showing up in U.S. streams, can alter genes responsible for building fish brains and controlling their behavior.

Antidepressants are the most commonly prescribed medications in the United States; about 250 million prescriptions are filled every year. And they also are the highest-documented drugs contaminating waterways, which has experts worried about fish. Traces of the drugs typically get into streams when people excrete them, then sewage treatment plants discharge the effluent.

Exposure to fluoxetine, known by the trade name Prozac, had a bizarre effect on male fathead minnows, according to new, unpublished research by scientists at the University of Wisconsin-Milwaukee.

Male minnows exposed to a small dose of the drug in laboratories ignored females. They spent more time under a tile, so their reproduction decreased and they took more time capturing prey, according to Rebecca Klaper, a professor of freshwater sciences who spoke about her findings at a Society of Environmental Toxicology and Chemistry conference last fall. Klaper said the doses of Prozac added to the fishes’ water were “very low concentrations,” 1 part per billion, which is found in some wastewater discharged into streams.

When the dose was increased, but still at levels found in some wastewater, females produced fewer eggs and males became aggressive, killing females in some cases, Klaper said at the conference.

The drugs seem to cause these behavioral problems by scrambling how genes in the fish brains are expressed, or turned on and off. The minnows were exposed when they were a couple of months old and still developing.

There appeared to be architectural changes to the young minnows’ brains, Klaper said at the toxicology conference. Growth of the axons, which are long nerve fibers that transmit information to the body, was disrupted.

The new findings build on Klaper’s previous research, which tested minnows with the gene changes to see how well they avoided predators. They swam longer distances and made more directional changes, which suggests that the drugs induced anxiety.

The drugs used in the study were among the most common in sewage: Prozac, Effexor and Tegretol. The researchers tested each drug alone and in combination.

“At high doses we expect brain changes,” Klaper said. “But we saw the gene expression changes and then behavioral changes at doses that we consider environmentally relevant.”

However, there is too little evidence to know whether pharmaceuticals are having any impacts on fish populations in the wild, said Bryan Brooks, an environmental science professor at Baylor University who has extensively studied pharmaceuticals in streams and fish.

Any changes in reproduction, eating and avoiding prey can have devastating impacts for fish populations, Klaper said.

The most vulnerable fish populations are those downstream of sewage treatment plants, where prescription drugs consistently show up in higher levels than in other waterways. It’s only within the past decade that technology has allowed plants to test for the chemicals in their wastewater and in waters downstream, though most still don’t, said Steve Carr, supervisor of the chemistry research group at the Los Angeles County Sanitation Districts.

One of the antidepressants tested in the fish – Tegretol – comes into the treatment plants and goes out at near constant levels, said Eric Nelson, a senior chemist with the Los Angeles County Sanitation Districts.

That means the county’s treatment technology does not seem to have any effect on the drug. It comes in and leaves in a very tight range, about 150 to 400 parts per trillion, Nelson said.

Nelson said the two other drugs tested on the fish – Prozac and Effexor  –  are discharged in effluent at even lower levels: between about 20 and 30 parts per trillion. In comparison, the levels that altered behavior of the lab fish were 50 times higher.

When monitoring an Iowa and a Colorado stream, the U.S. Geological Survey found most drugs at levels similar to Los Angeles County’s. However, these low levels could still find their way into fish brains, according to their 2010 study.

Researchers found elevated levels of pharmaceuticals in the stream water two to six miles from the sewage treatment plants. But the chemicals at the highest levels in the water were not the ones most prevalent in the fish brains.

“The fish downstream of the wastewater treatment had elevated concentrations of two antidepressants … Zoloft and Prozac,” said Edward Furlong, a research chemist at the U.S. Geological Survey based in Boulder, Colo. “And these were relatively low in water compared to others.”

Even if the levels released into streams seem low, they are constant, which is problematic, Brooks said.

“The drugs may not be classically persistent like PCBs,” Brooks said. “But they’re pseudo-persistent. The [continuous] exposure of organisms in a stream is equivalent to a chemical that is persistent.”

Some drugs bioaccumulate, or build up, in rainbow trout, according to Brooks’ research. Also, rainbow trout exposed to sewage effluent have pharmaceuticals in their blood at levels as high as those that affect the brains of people, according to research in Sweden.

Brooks said the likelihood of bioaccumulation for pharmaceuticals is high. “People have to take these drugs for weeks before they start having effects. They slowly bioaccumulate in your system,” which suggests bioaccumulation potential in fish, too, Brooks said.

Changes to the brain can affect all kinds of things in fish, Klaper said. And since humans have a similar brain gene structure, the findings raise questions about whether traces of these drugs in drinking water might harm human health.

The U.S. Environmental Protection Agency considers pharmaceuticals an “emerging concern,” and has concluded that the chemicals may pose risks to wildlife and humans. There are currently no federal regulations of the compounds in waste or drinking water. However, 12 pharmaceuticals are currently on the EPA’s Contaminant Candidate List, which are chemicals that may require regulation under the Safe Drinking Water Act.

Studies have consistently found prescription drugs in drinking water at parts-per-trillion levels. U.S. Geological Survey scientists sampled 74 waterways used for drinking water in 25 states in 2008 and found 53 had one or more of the three dozen pharmaceuticals they were testing for in their water. Forty percent of the pharmaceuticals were found at one or more of the sites.

Fifty-four active pharmaceutical ingredients and 10 metabolites have been detected in treated U.S. drinking water, according to a 2010 EPA review.

Studies of children exposed in the womb to antidepressants taken by their mothers show effects on their motor developmentand a higher risk of some birth defects.

But health officials say the levels found in some drinking water are too low to cause harm.

According to a 2012 World Health Organization report, the “trace quantities of pharmaceuticals in drinking water are very unlikely to pose risks to human health.” The report said that the amount found in drinking water is usually 1,000 times lower than doses expected to have an effect on a person.

But Klaper said that in light of the gene changes in fish brains, officials may need to rethink what is considered safe.

“Fish do not metabolize drugs like we do,” Klaper said. “Even if environmental doses aren’t thought to be much for a human, fish could still have significant accumulation, and, it appears, changes in their brain’s gene expression.”

This article originally ran at Environmental Health News, a news source published by Environmental Health Sciences, a nonprofit media company.  It is reprinted here for Scientific American. 

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Silver Inhibits the Growth or Bacteria in Water Filters, But It Is Not a Serious Biocide

Silver has for some time been used as an ingredient in water filters, especially carbon drinking water filters and ceramic filters.

It is also used in swimming pool purification devices.

When silver is used in a water filter, the EPA regulates it as a pesticide, so an EPA approval often appears on the product label. This has led to a false notion among the public (which is encouraged, I regret to say, by some manufacturers of water filters that contain silver) that such products are “certified” by the EPA as a guarantee of performance.  The EPA does not certify the performance of any product.  The EPA approval merely means that the filter contains so little silver that its water can be consumed safely by humans.

Another common false belief about silver in water filters is that it “kills bacteria,” meaning that it makes unsafe water safe to drink.  It does not.  Silver is classified as a “bacteriostatic” agent, not a biocide.  This means merely that it inhibits the growth of bacteria in existing filter beds.  For that reason it is sometimes added to carbon filters, since carbon provides a fertile growing place for harmless, non-pathogenic. heterotrophic bacteria.  Silver serves as a bacteriostatic agent, inhibiting that growth.  It can also serve a useful function when it is embeded  ceramic filters, where it can prevent bacteria from growing through the ceramic wall.

Although recent studies indicate that if given enough time silver can produce a 6 log reduction of bacteria, it is an extremely slow acting killer and its usefulness in this area is very limited.

 Street Cleaning Machines Are Essential Tools for Maintaining Clean Water

 

We usually think of street sweepers as big noisy machines that stir up dust and pick up some dirt, leaving the street looking a little nicer.  What we don’t consider is that street sweepers are an essential part of water treatment.

What we  call ‘street dirt’ is composed of heavy metals and other pollutants—items that may be killing fish when they get into waterways via stormwater runoff. Cities use media filters to clean stormwater, but it is estimated that effective street cleaning can greatly lessen the cost of filtering.  Cleaning the street as compared with filtering costs about one-forth as much, in fact.

Heavy metals like cadmium, copper, lead, zinc are specific pollutants that are found in abundance in “street dirt.”  In 1972, in the first USEPA publication ever on stormwater, street dirt was named as “the primary source of contamination, in terms of mass.”

Much of the toxic debris that washes to storm drains from the street is from automobiles.  Brake pads, for example, especially cheap brake pads, deposit large amounts of copper into the streets.  This copper ends up in the water supply unless it is caught in a filter or, more economically, swept up by a street cleaning machine.

Street sweeping machines vary in sophistication.  Early models, which go back centuries, were used for picking up horse manure before the advent of the automobile.  In the early 20th century, many US cities used them, but they were of limited effectiveness.

Mechanical machines, which use a main broom and conveyor belt to pick up material,  have been around at least 100 years. Their basic design hasn’t changed that much, although impressive improvements have been made, such as the broom design and speed, and the conveyor belt speed and alignment.  The mechanical machines are still the most popular, and perhaps 90% of the sweeping machines in operation are of the mechanical broom design.

Newer designs include “regenerative air” units which in one motion blow air down on the pavement to dislodge debris then immediately vacuum the dirt into a hopper.  These are sometimes unpopular because unless they include air filters they stir up lots of dust.  Vacuum machines can be very effective.

Even more advanced designs use water.  One machine features “rotary arms with nozzles on the end that  blow water down on the pavement; the back end of the machine features a powerful vacuum and a squeegee that sucks up the water and the debris it contains.”

The “state of the art” machine called the Schwarze A7000 costs in the neighborhood of $170,000.

The effectiveness of the machine, of course, is determined by how much dirt the machine actually picks up.  Ineffective machines simply move some of the dirt to a different location.  The worst street cleaner of all time, of course, as well as probably the stupidest machine ever devised, is the common leaf blower, which does not remove dirt but simply moves it to a less visible spot.

 

 

Why You Might Not Want To Live Next Door To A Wastewater Treatment Plant

“It’s been absolutely heinous. These flies are invading my space and it makes me feel gross.” –Bryan, Texas Resident Shannon Wolfert.

The story that we’re excerpting below concerns the invasion of a neighborhood in Bryan, Texas by dreaded filter flies, aka drain flies, sewer flies, moth flies.  Filter flies, as you might guess, are called filter flies because they love to congregate around water filters.  Not the water filter under your sink, but a specific type filter used in wastewater treatment that is called a “trickling filter.”   Here’s a good explanation of a trickling filter and how it works. 

A trickling filter consists of a bed of highly permeable media on whose surface a mixed population of microorganisms is developed as a slime layer.  The word “filter” in this case is not correctly used for there is no straining or filtering action involved.  Passage of wastewater through the filter causes the development of a gelatinous coating of bacteria, protozoa and other organisms on the media.  With time, the thickness of the slime layer increases preventing oxygen from penetrating the full depth of the slime layer.  In the absence of oxygen, anaerobic decomposition becomes active near the surface of the media.  The continual increase in the thickness of the slime layer, the production of anaerobic end products next to the media surface, and the maintenance of a hydraulic load to the filter, eventually causes sloughing of the slime layer to start to form.  This cycle is continuously repeated throughout the operation of a trickling filter.  For economy and to prevent clogging of the distribution nozzles, trickling filters should be preceded by primary sedimentation tanks equipped with scum collecting devices. 

Primary treatment ahead of trickling filters makes available the full capacity of the trickling filter for use in the conversion of non-settleable, colloidal and dissolved solids to living microscopic organisms and stable organic matter temporarily attached to the filter medium and to inorganic matter temporarily attached to the filter medium and to inorganic matter carried off with the effluent.  The attached material intermittently sloughs off and is carried away in the filter effluent.  For this reason, trickling filters should be followed by secondary sedimentation tanks to remove these sloughed solids and to produce a relatively clear effluent.  

It is easy to see how flies might develop a liking for a trickling filter, and the fact is that filter flies sometimes become such a nuisance that the filter has to be shut down to get rid of them.  Control of filter flies other than by turning off the filter is difficult because many traditional remedies don’t work well.  If chlorine is used to kill off the flies, for example, it also kills off the bacteria that make the filter work. When a trickling filter is shut down, unfortunately, the filter flies don’t vanish.  They just move. The piece below describes what happened when a trickling filter was shut down at the Bryan, Texas wastewater treatment plant. — Hardly Waite.

 

Flies invade homes after problem at wastewater treatment plant

by Beth Brown

A swarm of flies that bred in Bryan’s wastewater treatment facility has led the city to shut down a part of the system, prompting complaints as the insects quickly spread into the nearby neighborhood.

“I’m not going to say it’s been biblical conditions out there, but it’s been pretty heavy,” said Mark Jurica, Bryan’s treatment and compliance manager.

About a month ago, moth flies — also known as filter flies, drain flies or sewage flies — were seen at the trickling filter in Bryan’s wastewater treatment facility. After chlorine and fogging sprays failed to kill them fast enough, city officials were forced to turn off the filter.

The trickling filter is a 100-foot tank filled with rocks. While the filter is a cost-efficient way for the city to strip organisms from the water, its humidity and water also is a perfect breeding ground for the moth flies.

Shutting it down has eliminated the fly’s habitat and food supply, forcing them out of their homes and into the city.

The facility is near a residential area that includes Royal Oaks Gardens apartments, where the flies can be seen coating walls inside some apartments.

Shannon Wolfert, who lives at the complex off Carter Creek Parkway, said she started noticing flies about three weeks ago, and estimates she’s had about 400 flies inside her apartment. She’s stopped eating in her apartment, and she and her husband avoid turning on the air conditioning, because she knows the insects prefer cooler temperatures. 

Over the weekend, her husband sneezed out a fly.

“It’s been absolutely heinous,” Wolfert said. “These flies are invading my space and it makes me feel gross. I feel like I need to move out, clean everything, and then move back in.” The trickling filter has been in operation since 1981, and this is the first instance of a fly infestation, according to city officials who say they’ve been working with entomologists at Texas A&M to create an integrated pest management plan.

The entomologists say the swarm of flies is a result of the long, warm spring.

Chris Keefer, research scientist with the Center for Urban and Structural Entomology at Texas A&M, said the fly’s life cycle is about 21 days with perfect temperature conditions, which are high ’70s and low ’80s. They prefer standing and stale water, sewage, garbage and decomposing organic matter, which can collect in drains. They also lay eggs, which can hatch after all the adults seem to have been eradicated.

“You can kill all the adults off but there’s always immature states at the breeding site that are continuing,” Keefer said.

Roger Gold, an entomology professor at Texas A&M, said residents don’t need to buy cleaning products to kill the flies, but they should look to dry out any standing water in yards.

Jurica said the city has received complaints in a two- to three-block radius from the wastewater treatment facility, and they are hoping the flies will be mostly gone next week.

However, Jake Thurmond, property manager at Royal Oaks Gardens, said he’s been hearing that for weeks.

“The city has been giving us this PR mumbo-jumbo about how it’ll go away by itself, but that was two weeks ago,” Thurmond said.

Thurmond said 20 residents have turned in pest control requests, and the complex’s pest bill will likely double for the month. After several failed attempts to learn what was going on, he said, he received an email Thursday explaining what unfolded at the city facility.

He said he was given no advance notice about the city shutting down the trickling filter.

“I’ve got more important things to focus on than a fly infestation from the city’s lack of communication,” Thurmond said. “It’s definitely been an inconvenience, not only financially but interfering with our residents and being able to go about our daily operations.”

Jurica said the filter will not go back online because “it’s not worth the risk” after hearing back from people who have been affected by the flies. The trickling filter doesn’t require electricity, but the new effort will. To help clean the water, the city plans to use more blowers, which are big energy consumers since they run 24 hours a day.

He said the trickling filter was old technology, but it was “very effective.”

“I have had people call and say they have little kids and they aren’t able to do the things they want to do, like ride their bikes and what not,” Jurica said. “It’s not good business to turn it back on now.”

Reference Source: TheEagle.com

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Private Wells Should Be Tested  At Least Annually

City water supplies are tested for pathogens frequently–in some cases, several times a day.  Well owners, however, frequently hold the opinion that when they bought the property the well was tested and that means that it’s safe for life.

In most cases the testing that is done when a home changes hands is only the most rudimentary test for coliform.  Moreover, this test usually has little validity because realtors and even county officials often suggest that if the well fails, the seller of the property should “shock” treat it, then test again immediately.  Passing this test offers no assurance that bacteria won’t return as soon as effect of the massive chlorine dose  wears off.

The Texas Well Owners Network recommends at least annual testing for the following:

Fecal coliform bacteria.  The presence of coliform in water indicates that waste from humans or warm-blooded animals may have contaminated the water. Water contaminated with fecal coliform bacteria is more likely to have pathogens present that can cause diarrhea, cramps, nausea or other symptoms.  If coliform is found, most test agencies test immediately for a prominent member of the coliform family,  E coli.

Nitrates.  Water with nitrates at levels of 10 parts per million is considered unsafe for human consumption. Nitrate levels above 10 ppm can disrupt the ability of blood to carry oxygen throughout the body, resulting in a condition called methemoglobinemia. Infants younger than 6 months old and young livestock are most susceptible.

Total Dissolved Solids (TDS).  While high TDS itself offers no immediate threat to health,  an increase in salinity can indicate problems with the well.  Water with high TDS levels may leave deposits and have a salty taste. Additionally, using water with high TDS for irrigation may damage soil or plants.

In addition to the basic annual tests recommended by the Texas Well Owners Network,  common sense should mandate more extensive testing when a home with a well is purchased and on a regular basis thereafter.  Comprehensive testing at five year intervals at the very least would seem advisable.

The home owner is his own water superintendent.  If he doesn’t take care of his water, no one will.  A regular comprehensive water test can provide peace of mind in an age of rapid population growth,  agricultural excesses, and invasive petroleum development.

Most city and county governments offer inexpensive tests for coliform bacteria.  Nitrates and Total Dissolved Solids can be tested with inexpensive home testing devices,  and there are many excellent labs that offer comprehensive testing at a reasonable price.

To Chloraminate or Not to Chloraminate:  That Is the Burning Question Many City Water Departments Are Facing

Introductory Note by Gene Franks: Chloramine is not new.  It has been used as a disinfectant in US water supplies since the 1920s.  Nevertheless, when cities contemplate the change from chlorine to chloramine as their water disinfectant, there is usually controversy, sometimes heated. The change to chloramine is very important to aquarium owners, to beer and bread makers,  to dialysis clinics, and to the small percentage of people whose skin or respiratory system seems to be especially sensitive to chloramine.  There are also plumbing issues to be considered. Chloramine is often blamed for leaks in copper pipes.  To water treatment dealers, chloramine represents a challenge, since it is considerably more difficult to remove than chlorine. 

Since people usually form opinions based on how an issue affects them personally, I thought it would be good to reprint a chloramine article that looks at the issue from a different angle.  The piece reprinted below, in slightly truncated form, concerns the decision being considered in Marion, Ohio about whether to switch to chloramines or to seek out a completely different substitute for chlorine.  As you will note, and the most outspoken opponents of chloramine usually ignore this, the option to stick with chlorine as usual is actually not an option for the city because sticking with the status quo has already been vetoed by the EPA.  The city’s water has been found to be in violation of EPA standards, so a change is required.  In the article below, Aqua Ohio, the water supplier for the city, is getting pressure from several sources.

(Note that the terms “chloramine” and the plural “chloramines” are often used interchangeably. This is because although “monochloramine” is usually the water treatment product, chloramine actually exists in other forms, depending on water conditions such as pH.)

Chloramines: Best option?   Adapted from the Marion Star.

MARION — City Council asked Aqua Ohio to come up with alternative methods to using chloramines in the local water supply, but the company maintains that chloramines are the best option.

Council will hear from Aqua officials and the general public after the regularly-scheduled meeting. Aqua has met with the county commissioners and with City Council in the past. The Ohio Environmental Protection Agency will address the municipal services committee,

Council drafted a 45-day moratorium and gave it a first reading two weeks ago, in case Aqua did not comply with the wishes of council or the public. Council would issue a $10,000 fine for every day that Aqua put chloramines into the water if the moratorium were to go into effect.

Ed Kolodziej, the president and Chief Operating Officer of Aqua Ohio, said his company would have to “make a choice” if it came down to abiding by council’s ordinance or by federal regulations.

Chloramines are created when ammonia reacts with chlorine in the water. Aqua planned to switch the treatment process for Marion water from chlorine to a two-step process of chlorine and chloramines. Tom Schwing, Aqua Ohio’s environmental safety and compliance manager, said this is to stay in compliance with Ohio Environmental Protection Agency regulations.

According to the EPA, chlorine alone forms many byproducts, including trihalomethanes (THMs) and haloacetic acids (HAAs). Some THMs are carcinogens. The EPA wants water systems to measure the output of these byproducts every quarter. In the past, Schwing said, the EPA averaged all the separate test sites together to see how many THMs and HAAs are in the water. Now, the EPA will look at how many of these byproducts are at each individual site, and keep a running average over the last four quarters.

Some of the Marion areas are at risk of going over the EPA’s limit, Schwing said, so Aqua needs to find a sanitation method that keeps the water cleaner for longer periods of time while it is in the pipes.

Chloramine forms a lower level of THMs and HAAs, but it has some health risks, according to the EPA. People on dialysis and people with fish tanks should not use chloraminated water because the ammonia is harmful when inserted directly in the bloodstream.

People from across the country have reported negative effects of chloramines, from skin rashes and respiratory problems to damage in their house’s pipes. Several groups have been established to combat the use of chloramines. Aqua said there have been no studies proving that chloramines cause any negative effects, but a group of Marion residents and some members of local government are worried about the chemicals’ potential to harm.

Other options

Kolodziej and Tom Schwing, Aqua Ohio’s environmental safety and compliance manager, said chloramines are the most cost-effective option for staying in the EPA’s guidelines.

Of the available water treatment options, they said, three would work in Marion and would reduce the harmful byproducts in the water. One is chloramines, one is a granular-activated carbon (GAC) filtration system, and one is an ozonation and biological filtration process.

Kolodziej said chloramines are a smaller capital investment, and they cost consumers less. He said the addition of chloramines to the water would be an 80 cent increase per month on customers’ water bills, and the other two options would be upwards of $13 per month. Building a facility for chloramines would cost Aqua about $790,000 and preparing the system for the other two options would be about $10 million each, he said.

Schwing said Aqua’s other facilities, such as the ones near Lake Erie, draw water from cleaner sources and can use different methods for keeping the water safe. He said only certain methods work for Marion. He also said that since Marion’s water supply stays in the pipes longer, chloramines will help keep the disinfection byproducts low in the outlying areas.

Schwing said there are downsides to the other methods of disinfection, and that Aqua would have to pay for testing and construction before implementing new methods. The chloramination equipment is currently under construction at the plant.

GAC filters can prevent or remove the disinfection byproducts, and would absorb any bad biomaterial, according to the Siemens water technologies website. Ozonation would take this process a step further by injecting ozone into the water before running it through a GAC filter or another biological filter. According to Ozone Technology, Inc., ozonation will react with the water and increase the effectiveness of the biofilters downstream.

Editor’s Note: The Marion Star article ends with a long list of cities in Ohio and worldwide that use chloramine and a long list of cities that don’t. This 2013 article presents the pros and cons of a controversy that hasn’t changed much. More and more cities are switching to chloramine but the controversy goes on. The switch is not always controversial. Our local water department has used chloramine for many years and most of our local customers, even the most health conscious, call it “chlorine” and are not even aware of the issue. From a treatment perspective, chloramine is harder to remove than chlorine, but by no means impossible to treat. The sticky issue is, what happens to the ammonia? Here’s a list of Pure Water Gazette articles that will tell you more than you want to know about chloramines. I especially recommend Chloramine Removal for which Emily McBroom and I spent several months of Saturdays testing a variety of real water treatment devices for chloramine/ammonia removal.

Reference:  Marion Star.

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How Nitrates Are Removed from Drinking Water

 

Although nitrogen occurs naturally in the environment and is necessary to support plant life,  nitrates can become serious water contaminants.

When taken into the body, nitrates convert to nitrites and are the cause of a number of serious ailments, the most known being “Blue Baby” syndrome.

The main source of nitrates in drinking water is agricultural fertilizer. Other sources include human sewage and livestock manure. Please refer to the  Pure Water Products’ Nitrate Factsheet.

The EPA, which sets a Maximum Contaminant Level for nitrates at 10 parts per million, recommends two methods for removing nitrates from water–reverse osmosis and ion exchange.

For drinking water in the home, reverse osmosis is the most common and easiest to apply.  A simple undersink reverse osmosis unit easily removes 95% or more of nitrates from tap water.  Small home distillers can also remove nitrates, as can specially designed ion exchange cartridges for standard water filters.

For larger amounts of water, from single residence wells up to small municipal sizes, the most common removal techniques is ion exchange.

Municipal water treatment plants also resort to blending,  a technique by which water with a high nitrate content is mixed with water with a lower content to produce a blend that meets standards.

Ion exchange, in the case of nitrate reduction,  is more precisely anion exchange. The ion exchange system used for nitrate removal is very similar to a water softener but instead of using softening resin,  which is a cation ion exchange resin, nitrate removal systems use an anion exchange resin. Both systems use sodium chloride salt (brine) to regenerate the ion resin bed.

Nitrate removal is not as simple as hardness removal. Two basic types of anion exchange resin can used, either Strong Base or Nitrate Specific. The latter is more expensive, costing usually about 50% more,  but simpler to use. It is frequently used by private well owners because it is more easily managed.

A Type II Anion (strong base) is best applied to municipal supplies where there is regular testing and maintenance of the system. Because Type II Anion resin is not nitrate selective there will be other ions, primarily sulfate, that compete for the exchange site. To properly size up this system, a complete water analysis will be required to ensure complete compliance and avoid nitrate “dumping” as the system approaches exhaustion. The nitrate level during dumping can be many times higher than the untreated nitrate concentration.

Nitrate selective anion resin is an option used principally on smaller municipal systems and private well sources. Nitrate selective anion resin strongly prefers the nitrate ions to the competing sulfate ions. With this resin we avoid nitrate “dumping”. In general this resin may be up to 50% more in cost.

Reference:  reschem.com.

 

In Iowa, nitrate levels in water have reached levels never seen before.

After a long drought, a soggy spring washed fertilizers and manure off of farms and into the rivers that provide drinking water. The elevated nitrate levels are becoming a threat to human health.

According to an AP article:

Nitrate levels have soared because drought-withered corn plants didn’t suck up all the nitrogen spread on fields last year. The drought was followed by Iowa’s wettest April in 141 years, and that rain washed unused fertilizer into rivers, the primary source of drinking water for 45 percent of the state’s population.

Nitrate in water is an issue throughout the Midwest, but Iowa is especially vulnerable because about 90 percent of the state is dedicated to agriculture. Corn requires an abundant supply of nitrogen, which must be added to the soil through the application of nitrogen fertilizer or manure. 

The Environmental Protection Agency requires nitrate in drinking water be kept at less than 10 milligrams per liter. Above that level can be deadly to infants younger than 6 months because the chemical can reduce the amount of oxygen carried in their blood. Pregnant women are advised not to drink water above the EPA limit, as are adults with reduced stomach acidity. There is conflicting evidence and expert opinion regarding nitrates as a cancer causer.

Without careful management, corn in the field can turn to nitrates in the water.

One river in Iowa, the Racoon River upstream from Des Moines, had nitrate readings of 24 mg/L last year. The Des Moines River reported a record high 18 mg/L.  Both rivers furnish drinking water for Des Moines. The city of Cedar Rapids has also experienced high levels of nitrates.

Many city water plants lack the equipment needed to reduce nitrate levels and are reduced to blending high nitrate water with water of better quality to produce an acceptable (below 10 mg/L) product. Other cities, like Des Moines, have expensive nitrate reduction equipment but prefer not to use it because of high operating cost.

Iowa and Illinois rivers typically have some of the nation’s highest nitrate levels, but other top corn states also have issues, including Indiana, Michigan, Minnesota, Ohio, Wisconsin and the eastern portions of Kansas, Nebraska, North Dakota and South Dakota.

According to the AP article cited above, nitrate levels in those states have been rising since the 1950s but leveled off in the 1980s. In the last five years, they’ve been climbing again as high corn prices have driven farmers to plant near-record corn acres. One official said: “In essence what we’re doing is subsidizing cheap food,  paying for it through the high cost of cleaning up our water after it’s contaminated by fertilizer.” 

And the cost indeed is high.  Des Moines has now had to switch on a $4 million nitrate reduction system that costs $7,000 per day to operate. In some Minnesota cities, the price of water has risen dramatically.

The nitrate invasion is, of course, the logical result of an unsustainable agricultural system that is focused entirely on short-term profits without regard to the consequences.  Farmers are being encouraged to limit fertilizer use and to leave plants in the field to lessen erosion, and  many have made changes.  But for most, it’s agribusiness as usual and the rivers be damned.

While it is difficult for city water suppliers to remove nitrates from the millions of daily gallons they process, it is relatively easy for homeowners to remove nitrates from drinking water. Reverse osmosis removes nitrates handily.

Source Reference: Article above drew information from a 2013 article from PostBulletin.com.

Gazette Fair Use Statement

Cracking water pipes afflict Rockwell City’s waste water treatment plant

Introductory Note:  We’re publishing the piece below as a footnote to recent articles about the plight of water departments facing the high cost of fixing or replacing decrepit water infrastructure. The EPA estimates that the US will need $400 billion for infrastructure upgrades over the next twenty years. 

The water main on High Street, however, will need to be replaced in the near future. Three to four city blocks of pipeline, including a section which passes under old Hwy 20, have seen constant repairs over the past few years. The lines will now be dug up and replaced at an estimated preliminary cost of around $200,000. Some of that cost will include the replacement of the road the pipes run under.

Reference Source:  CBC Online.

 Many of the Nation’s Water Treatment Facilities Are Long Overdue for Upgrade

 

According to the Environmental Protection Agency,  nearly $400 billion in infrastructure spending is needed over the next twenty years to ensure that Americans continue to have safe drinking water.