Are Nitrates in Water A Cancer Risk?

A peer reviewed study published by the Environmental Working Group proposes that nitrate pollution of U.S. drinking water may cause from 2300 to 12,594 cases of cancer per year.  Most of these cases are in the rural farmland area where agronomic inputs, septic systems and home lawns becomes the source of this contamination.  Currently, the EPA acceptable level is 10ppm, but the EWG wants to see a lower level, about 0.14 ppm.

These statistical studies make a lot of inferences based on diverse data, so it is important to recognize the limit of this.

Jeff Stoltzfus, Penn State's Farm Food Safety Educator, was kind enough to provide some facts.  First, the baseline level, or background level, found in undisturbed aquifers is 1ppm and as high as 3ppm.  Vegetables and meat also contribute significant amounts of nitrates to our diet.  Finally, there are many, many activities we engage in each day that represent a higher risk than this.

Environmental Research, online 11 June 2019, https://doi.org/10.1016/j.envres.2019.04.009

https://www.sciencedirect.com/science/article/pii/S001393511930218X?via%3Dihub
Exposure-based assessment and economic valuation of adverse birth outcomes and cancer risk due to nitrate in United States drinking water.
 Alexis Temkin a, Sydney Evans a, Tatiana Manidis b, Chris Campbell a, Olga V. Naidenko a
https://doi.org/10.1016/j.envres.2019.04.009

Highlights

• First of its kind national analysis assessing nitrate exposure from drinking water for the entire U.S. population.
• 2,300 to 12,594 nitrate-attributable cancer cases annually in the U.S., of which 54-82% are colorectal cancer (CRC) cases.
• Up to $1.5 and $6.5 billion in medical and indirect costs may be associated with annual nitrate-attributable cancer cases.
• Meta-analysis of eight studies assessing nitrate in drinking water and CRC supports a health benchmark of 0.14 mg/L

CDC MMWR Report - 2017 Legionella Outbreak Associated with Memphis Hotel Hot Tub

In the January 19th MMWR release, an investigative report into a 2017 Legionella outbreak associated with a hotel hot tub and pool.  While the outbreak came to light because of a few cases, many more were found through old-fashioned investigative work rather than sample analysis.

Initially 3 cases were identified, and this led them to the hot tub.  Through proceeding to survey past guest, 92 cases were identified, including nine laboratory-confirmed (urinary antigen positive) cases, 19 probable (self-reported pneumonia) cases, and 64 suspected (self-reported fever and ≥1 compatible symptom*) cases.  Of these, 70 had required medical care, and 16 people were hospitalized and there was one reported death.

Not the way to meet up with Elvis after going into a Memphis hotel hot tub, or any hotel water for that matter.  But how do you know?  In this case, "environmental health specialists conducted an assessment of the hotel aquatics facility and identified improper water treatment monitoring and low chlorine residuals (0 ppm; acceptable range = 1–3 ppm)."  "Laboratory testing of the aquatics facility water samples identified three Legionella polymerase chain reaction–positive samples from the pool, pool sand filter, and hot tub sand filter, and isolated Legionella pneumophila serogroup 1 from the hot tub sand filter."   Something to be said about that smell of chlorine when poolside.

CDC MMWR
https://www.cdc.gov/mmwr/volumes/67/wr/mm6702a5.htm?s_cid=mm6702a5_e
Notes from the Field: Legionellosis Outbreak Associated with a Hotel Aquatics Facility — Tennessee, 2017

New Trend - Drinking 'Raw Water'

There is a new trend...'raw water'...water that is unfiltered, untreated spring water. A article in the New York Times, Unfiltered Fervor: The Rush to Get Off the Water Grid discusses a Oregon operation, Live Water, is selling water for $14.99/bottle refill while a San Diego operation sells their version for $2.50/gallon.

"The quest for pure water is hardly new; people have been drinking from natural springs and collecting rainwater from time immemorial. The crusade against adding fluoride to public water began in the 1950s among Americans who saw danger in the protective measures that had been adopted over decades to protect the populace from disease and contamination.  But the off-grid water movement has become more than the fringe phenomenon it once was, with sophisticated marketing, cultural cachet, millions of dollars in funding and influential supporters from Silicon Valley."

One can also purchase water collection systems that capture moisture from the air.

From a safety perspective, without treating water, one opens themselves to increased risk to a host of  microbial pathogens including bacteria and parasites such as Giardia and Cryptosporidium, .  Beyond that, people across globe do not have access to clean water and would prefer avoid drinking 'raw' water.  The article below, from National Review, sums that up pretty well.

National Review
‘Raw Water’ Makes a Mockery of Human Suffering
Read more at: http://www.nationalreview.com/article/455235/raw-water-movement-mocks-human-suffering
by Jibran Khan January 8, 2018 1:05 PM

It’s a play-act of poverty that puts ‘slum tourism’ to shame. Every few months, there’s a new trend that promises life-changing health benefits — a spice, or a juice, or another mundane consumable, often with an Indian or East Asian name thrown in to make it seem ancient and exotic. We see these things, laugh, and move on with our lives. We live and let live.

CDC MMWR - Waterborne Disease Outbreaks from Drinking Water - 2013 to 2014

As an important raw material for most food operations, water must be evaluated as part of the hazard analysis. The source of the water as well as how that water is stored and used must be considered. In CDC's report, disease outbreaks associated with drinking water (period 2013-2014) are reviewed. By their definition, "for an event to be defined as a waterborne disease outbreak, two or more cases must be linked epidemiologically by time, location of water exposure, and illness characteristics; and the epidemiologic evidence must implicate water exposure as the probable source of illness."

A summary of key findings:

• "Legionella was implicated in 24 (57%) outbreaks, 130 (13%) cases, 109 (88%) hospitalizations, and all 13 deaths (Table 1). Eight outbreaks caused by two parasites resulted in 289 (29%) cases, among which 279 (97%) were caused by Cryptosporidium, and 10 (3%) were caused by Giardia duodenalis. Chemicals or toxins were implicated in four outbreaks involving 499 cases, with 13 hospitalizations, including the first reported outbreaks (two outbreaks) associated with algal toxins in drinking water."
• "Thirty-five (83%) outbreaks were associated with public (i.e., regulated), community or noncommunity water systems,¶ and three (7%) were associated with unregulated, individual systems. Fourteen outbreaks occurred in drinking water systems with groundwater sources and an additional 14 occurred in drinking water systems with surface water sources. The most commonly cited deficiency, which led to 24** (57%) of the 42 drinking water–associated outbreaks, was the presence of Legionella in drinking water systems"
• "All of the outbreak-associated deaths reported during this surveillance period as well as all of the outbreaks reported in hospital/health care settings or long-term care facilities, were caused by Legionella. A review of 27 Legionnaires’ disease outbreak investigations in which CDC participated during 2000–2014 identified at least one water system maintenance deficiency in all 23 investigations for which this information was available, indicating that effective water management programs in buildings at increased risk for Legionella growth and transmission (e.g., those with more than 10 stories or that house "
• "Cryptosporidium was the second most common cause of both outbreaks and illnesses, demonstrating the continued threat from this chlorine-tolerant pathogen when drinking water supplies are contaminated."

Some background from one of the references (copied below) on Legionella in water systems.

• "Legionnaires’ disease is a lung infection that is fatal for about one in 10 persons who become infected. Legionella, the bacterium that causes Legionnaires’ disease, grows well in warm water, but can be killed by disinfectants, such as chlorine. Persons can get Legionnaires’ disease when they breathe in small droplets of water contaminated with Legionella."
• "Legionella grows best in building water systems that are not well maintained, especially where levels of chlorine or other disinfectants are low and water temperatures are optimal for its growth. Legionnaires’ disease outbreaks most often occur in hotels, long-term care facilities, and hospitals. The most common sources are potable water (e.g., drinkable water used for showering), cooling towers, hot tubs, and decorative fountains."

CDC MMWR
https://www.cdc.gov/mmwr/volumes/66/wr/mm6644a3.htm?s_cid=mm6644a3_e
Surveillance for Waterborne Disease Outbreaks Associated with Drinking Water — United States, 2013–2014
Weekly / November 10, 2017 / 66(44);1216–1221

FDA Delays Compliance Dates for Agricultural Water as Part of FSMA Produce Safety Rule

The FDA announced that it is planning to extend the deadline for compliance to agricultural water standards used in irrigation as part of the FSMA Produce Safety Rule .  Irrigation water can be a source of pathogens, but it is not an easy to control, especially when that water comes from surface waters.  Work done here at Penn State by Luke LaBorde etal (ref below) found that it was hard to make a connection between water standards and pathogen levels.  So testing water to see if it meets standards that may not mean much in terms of the pathogens present.  It is easy to see how environmental factors will constantly change...whether that be the occasional presence of animals, the amount of rainfall, the amount of sunshine, etc.

For more information on irrigation water, visit the Penn State Extension Website -http://extension.psu.edu/food/safety/farm/gaps/safe-uses-of-agricultural-water

Food Safety Modernization Act (FSMA) Updates
FDA Intends to Extend Compliance Dates for Agricultural Water Standards

Earlier this year, the U.S. Food and Drug Administration announced that it is exploring ways to simplify the agricultural water standards established by the Food Safety Modernization Act’s (FSMA) produce safety rule (PSR) after receiving feedback from stakeholders that some of the requirements are too complex to understand and implement.

WA Institutional Food Processor Recalls Food After Learning of Water Contamination Issue

A Washington state establishment which manufacturers food for correctional facilities, senior centers, and county jails, is recalling 319, 000 lbs of food after being notified by the local water authority that the well water used to manufacture their products may be contaminated with hazardous chemicals. This contamination issue also affects the local city's drinking water.

The chemicals, Perfluorooctanesulfonic acid (PFOS) and Perfluorooctanoic acid (PFOA), originated from the local Air Force base where they were used in fire fighting spray.  While these chemicals are above EPA standards, there are no food safety regulations. The EPA classifies these as emerging contaminants.with a limit of 70 parts per trillion.  The wells were found to have 1100 parts per trillion.  The chemicals do not have an acute affect at this level, but the concern is for cumulative exposure where they can cause liver damage, cancer, among other negative health affects.  

It is important to understand where a facility's water comes from and potential contamination issues, even if it is municipal water and/or well water.  Are the wells in areas where there has been past contamination issues?  What is the depth of the well?  How often is the water monitored and what is it monitored for?

UDSA /FSIS Recall Notice
https://www.fsis.usda.gov/wps/portal/fsis/topics/recalls-and-public-health-alerts/recall-case-archive/archive/2017/recall-053-2017-release
Correctional Industries Airway Heights Food Operations Recalls Frozen Meat and Poultry Products Due to Water Contamination
Class II Recall 053-2017
Health Risk: Low May 20, 2017

CDC Report - 2016 E.coli (STEC) Outbreak Linked to Stream Water Contaminated with Deer Feces

In May of 2016, 4 children became infected with Shiga toxin-producing E. coli (STEC) after playing in a stream in a city park.  After an investigation, the likely source was determined to be deer poop (aka scat).  According to the report, "MLVA profiles were identical for the case-patient, water, and deer scat isolates".

The presence of E. coli in the water varied over time. Coyote scat also had E. coli of similar makeup..but this may be related to the fact the coyote is drinking that same water.  What this does show is that surface water is prone to contamination from animal feces and this contamination can be passed to humans directly through intake of that water or potentially through food irrigated with that water.

CDC - Emerging and Infectious Disease

https://wwwnc.cdc.gov/eid/article/23/7/17-0226_article
Contaminated Stream Water as Source for Escherichia coli O157 Illness in Children

Abstract

In May 2016, an outbreak of Shiga toxin–producing Escherichia coli O157 infections occurred among children who had played in a stream flowing through a park. Analysis of E. coli isolates from the patients, stream water, and deer and coyote scat showed that feces from deer were the most likely source of contamination.

The Importance of Backflow Prevention

Questions often arise on the need for backflow prevention devices on water spigots in food establishments. Backflow occurs when non-potable water is pulled into the potable water via a cross-connection - is a physical link between potable and non-potable water, such as a hose.  Backflow occurs when there is a high movement of water through a water main, which generates negative pressure in the cross connection, causing back-siphonage or backflow from the non-potable water source through the cross-connection, whether that be a hose or a pipe.  This is due to Bernoulli's principle.

Examples of cross connections can be someone dropping a hose connected to a sink into a mop bucket containing floor cleaner, or someone dropping an outside hose into a non-chlorinated swimming pool (green) or into puddle of water.  Hoses, however, are not the only issue.  An often overlooked connection is the direct water feed into chemical mixing systems.   Hazards related to backflow are not always biological.  Chemicals can be pulled into the water source, especially through this direct water feed into chemical mixing / dispensing systems.

Of course it is best not to make that cross connection, but this is not always easy when using hoses.  Where hoses are used, it is important to make sure back flow prevention devices are installed.
Pressure deficiencies, such as when there is a water main break, also can result in backflow into the potable water source.

Coliform Positive Sample in Well Water Results in Product Recall

A PA meat establishment is recalling pork products after inspectors found the facility's water test results had been positive for coliform bacteria.  These test results would classify the water as non-potable.

While the risk is probably low to non-existent (the fresh pork itself would have coliforms), the water used to make that product is deemed as non-potable.  While the presence of coliforms in themselves are not a hazard, their presence could indicate that other pathogenic bacteria could be present.  More importantly, their presence could indicate that  a contamination pathway could exist linking the water supply to a contamination source - surface water, septic system, animal waste, etc.

Corrective action needs to be taken immediately upon these types of results. This is normally done by dosing or shocking the well with chlorine. or even better for protecting a business is continuous disinfection.
 
FSIS News Release
http://www.fsis.usda.gov/wps/wcm/connect/FSIS-Content/internet/main/topics/recalls-and-public-health-alerts/recall-case-archive/archive/2016/recall-082-2016-release
Bunge's Meats Recalls Pork Products Formulated With Water That Did Not EPA Meet Drinking Water Standards
Class I Recall 082-2016
Health Risk: High Sep 16, 2016 

Bottled Water Recalled Due to Milk Allergen

A Texas company is recalling gallons of bottled water after a quality review found that the water may have milk allergen in it.

How can something like this arise?  Often times milk bottling operations will also bottle water using the same equipment (cold fill type of operation).  A good sanitation regime should get rid of any residual allergens, but if something is not completed properly, residual allergens may be left in pipes or the filler.

FDA Recall Notice
http://www.fda.gov/Safety/Recalls/ucm461121.htm
H-E-B Issues A Voluntary Recall On Hill Country Fare One Gallon Spring Water Due To The Possible Presence Of Undeclared Allergen

Voluntary recall specific only to stores in the Houston, Central Texas and the Gulf Coast areas

Contact:  Consumer: Leslie Sweet, H-E-B (512) 293-1220

FOR IMMEDIATE RELEASE – September 2, 2015 – Austin, TX – H-E-B has issued a voluntary recall specifically for the Hill Country Fare One Gallon Spring Water with the Best By date of December 19, 2015, due to the possible presence of a milk allergen. People who have an allergy or severe sensitivity to milk run the risk of a serious or life-threatening allergic reaction if they consume this product. There have been no consumer complaints or reports of illness.

H-E-B discovered the issue on September 1, 2015, during quality assurance product reviews. This recall is specific to one gallon containers of Hill Country Fare Spring Water with a Best By Date of December 19, 2015. No other H-E-B or Hill Country Fare products are impacted by this voluntary recall.

MMWR - Outbreaks Associated with Drinking Water - 2011-2012

 We generally regard drinking water safe, and rightfully so.  For the amount of water that is consumed each day, there have been relatively few issues.  An MMWR article reports that in the two year period reviewed, 2011-2012, there have been 32 water related outbreaks resulting in 431 cases of illness, 102 hospitalizations, and 14 deaths.

The biggest culprit was Legionella and this was primarily related to drinking water in hospitals affecting at-risk patients.  While we hear of Legionella in air conditioning systems, such as the current issue in NY where over 100 have become ill and 12 have died (Legionella grows in the cooling water systems and then is inhaled through the water vapors), evidently Legionella is an issue in hospitals (along with other HAIs (hospital acquired infections) including Clostridium difficile, MRSA, etc).  "Legionella outbreaks are particularly challenging to prevent and control, in part because the organism lives and multiplies in building plumbing systems, which usually fall outside water utility and regulatory oversight (6,7). One Legionella outbreak occurred in a hotel that used point-of-entry water filters, which effectively dechlorinated all water entering the building, and illustrates the importance of maintaining sufficient residual disinfectant in plumbing systems."

EPA has a publication on Legionella in drinking water.

The other issue was non-community water systems.  "All five noncommunity outbreaks originated from groundwater sources. Specifically, four occurred in outdoor camp or work settings where a source spring was contaminated directly or by inflow from a stream, and the fifth occurred at a meeting facility where a well was contaminated with septic tank overflow."  In these cases, Norovirus, non-Legionella bacteria, and Giardia (a parasite) were responsible.   (You are probably wondering how you ever made it through summer camp as a kid considering the pond water where you swam and that nasty spigot you drank from....and you are also then wondering why your parents sent you there.)

Here, an elk enjoys a drink of water from a spigot used for filling water bottles at Grand Canyon National Park (photo courtesy of Nika Bucknavage).

CDC MMWR
http://www.cdc.gov/mmwr/preview/mmwrhtml/mm6431a2.htm?s_cid=mm6431a2_e
Surveillance for Waterborne Disease Outbreaks Associated with Drinking Water — United States, 2011–2012

Weekly
August 14, 2015 / 64(31);842-848
Karlyn D. Beer, PhD1,2; Julia W. Gargano, PhD2; Virginia A. Roberts, MSPH2; Vincent R. Hill, PhD2; Laurel E. Garrison, MPH3; Preeta K. Kutty, MD3; Elizabeth D. Hilborn, DVM4; Timothy J. Wade, PhD4; Kathleen E. Fullerton, MPH2; Jonathan S. Yoder, MPH, MSW2

Advances in water management and sanitation have substantially reduced waterborne disease in the United States, although outbreaks continue to occur (1). Public health agencies in the U.S. states and territories* report information on waterborne disease outbreaks to the CDC Waterborne Disease and Outbreak Surveillance System (http://www.cdc.gov/healthywater/surveillance/index.html). For 2011–2012, 32 drinking water–associated outbreaks were reported, accounting for at least 431 cases of illness, 102 hospitalizations, and 14 deaths. Legionella was responsible for 66% of outbreaks and 26% of illnesses, and viruses and non-Legionella bacteria together accounted for 16% of outbreaks and 53% of illnesses. The two most commonly identified deficiencies† leading to drinking water–associated outbreaks were Legionella in building plumbing§ systems (66%) and untreated groundwater (13%). Continued vigilance by public health, regulatory, and industry professionals to identify and correct deficiencies associated with building plumbing systems and groundwater systems could prevent most reported outbreaks and illnesses associated with drinking water systems.

Bottle Water Recalled Due to E. coli

On June 23rd, a Canadian company recalled bottled water produced at two Pennsylvania bottling facilities.  These plants produced a number of store brands for various retail customers.

Bottling water seems easy, but any manufactured food or beverage product must be produced with adequate food safety systems in place.

In this case, generic E. coli were found, which are not necessarily pathogens.  But the presence of these organisms indicates the potential for enteric pathogens, and at the least, that unsanitary conditions exist.  Companies use E. coli testing because it is a good indicator and is a relatively simple analysis.

Huffington Post
http://www.huffingtonpost.com/2015/06/22/bottled-water-e-coli-contamination_n_7640010.html
14 Brands Of Bottled Water Voluntarily Recalled Due To Potential E. Coli Contamination
By Alena Hall 
Posted: 06/22/2015 5:51 pm EDT Updated: 06/23/2015 11:59 am EDT

A water bottling company that is responsible for 14 different brands issued a voluntary recall on Monday after discovering that one of their spring water sources tested positive for E. coli bacteria.

“E. coli are bacteria whose presence indicates that the water may be contaminated with human or animal wastes," a representative of Niagara Bottling LLC said in a statement. "Microbes in these wastes can cause diarrhea, cramps, nausea, headaches, or other symptoms. They may pose a special health risk for infants, young children, some of the elderly and people with severely compromised immune systems."

Knowing Your Water Source - Ground Water Awareness Week

This coming week is Ground Water Awareness Week, and this is good time to understand where your water comes from, even if it is through a municipality, and what impact there would be for your product/process if there would be a water contamination event, such as brown water coming out of the spigots, bad test results,  or an announcement of a boil advisory by the municipal provider.

There have been a number of outbreaks associated with drinking water,  but the risk of contamination to a food establishment is dependent upon the types of processes run.  So it is important to conduct a risk analysis, considering you water source, the types of contaminates that can be present, and the impact of your processes on those contaminates.

The types of contaminates in water can be found on the EPA website (US Environmental Protection Agency. Drinking water contaminants. http://www.epa.gov/safewater/contaminants/index.html).

General information on well water can be found on the CDC Websites:

• http://www.cdc.gov/healthywater/drinking/private/wells/index.html
• http://www.cdc.gov/healthywater/drinking/training-education.html#webtraining.

Penn State Extension has a link on Preparing for a Water Emergency.