H2O - Healthy Hawaiian Oceans

“Malama o kekai, kekai o ke malama”

Take care of the sea, and the sea will take care of you

Post Office Box 895

Honaunau, Hawai`i 96726


Tuesday, July 10, 2018

Sunscreen for Germs?

Unintentional Sunscreen for Water Germs
R.H. Bennett Ph.D.
Applied Life Sciences LLC

Few if any would suggest even for a second, that the Sun in Hawai‘i is anything but intense.  During outrigger canoe racing season we would hope for the Trade Wind Clouds to shield us from the heat and suns burning rays.  These Ultra Violet B rays and the inflammatory radiation “burn” they cause have ruined days, vacations and even sent people to the emergency room.  To be clear, this is ultraviolet radiation and not gamma radiation as in x-rays.
  There are many approaches to preventing sunburn.  The most effective is to simply and completely shade the skin from the sun. However, this is almost antithetical for those on a Hawaiian vacation.
The data on the left is for UV intensity for Honolulu mid-summer. Note that UV radiation is considered “Extreme” from about 10 AM to 1 PM. This is the time to “shade up” or suffer the consequences.

It’s A Good Thing!
Another perspective about UV B rays and our well-being is its daily, powerful and very effective irradiation of the ocean waters.  At first, this may sound like so much gibberish. However, let us shine some light on it. 
Nearshore waters of Hawai’i bathe people recreating in the sea.  This bathing rinses human bacteria from all of our nooks and crannies. For surfers, this bathing is more like a high-pressure car wash with each crashing wipe out.  Most people just wade and play in the gentle surf and warm Tropical Ocean. In so doing people and the waves stir up the sand and the potentially harmful bacteria that harbor there. There are far more bacteria like Staph and Enterococci in the sand than in the water column (Goodwin 2012, Yamahara 2012). As the bacteria get suspended in the upper water layer, the UV B can do its job.

 This very same ocean is the sea level to which all most all waters from the land are destined.   Waters from the streams traversing the mountain and countryside’s, rain waters from street runoff, sewer waters from old leaking pipes, wastewaters from underground cesspits and septic systems all are on an inexorable flow to the sea. The bacterial loads in these waters are staggering, and a few of the species are known pathogens.   When people are contaminated, or ill their pathogens may well join this water at any place from the mountain to the sea.  It is water that gives bacteria “wings."

 Please interrupt any emerging notion of staying out of the ocean forever more and considering Nature’s grand disinfectant is at work to bring some stability to the ocean ecosystem.  The world’s oceans are home to trillion - trillion microorganisms.  This science is so new the microbes have not been named yet.  The vast majority of the ocean microbes play roles in the life systems of the sea.  Nature has a way to manage the burgeoning bacterial populations for reasons scientists have just begun to imagine.

 The sun rises, and by 10 AM on most days maximal UV B from El Sol strikes the water penetrating and killing microbes of all types.  Within the first foot or so there is sufficient UV B energy to fracture the DNA strands and in so doing render the irradiated microbes inactive (Maricini 2016, Deller 2006).

More than likely, this solar radiation is killing multitudes of bacteria, including those that can prey on people and this most likely explains why scores of people are not lining up at the clinics with ocean-related infections.  Next time we are inclined to curse the intensely hot sun, consider all the good it is doing to keep the ocean a little cleaner and safer.  However, things appear to be changing.

 Things are changing. Safety is Compromised

We use and dispose of much water.  Estimates place personal water use at 80 to 100 gallons per day (USGS 2016).  Ultimately in Hawai‘i, that water finds its way to the sea (Lau and Mink 2006), and it carries what it may along the way.  As the population grows even in remote places more and more, wastewater joins the water cycle.

 Obviously human and environmental microbes are part of that flow.  Just as essential is the nutrients; nitrogen and phosphorus get transported in the waters. (See the previous blog on Nitrogen)  It is here that these nutrients and the microbes in water come to play out in a human-made change that compromises recreation water safety.

In brief, water nutrients in lakes and oceans promote microscopic plants.  In freshwater greening is caused by algae. In the ocean, greening can be due to phytoplankton and marine algae.  Greening of these waters is mostly invisible until the plant like microbes become very abundant.  The result is an increase in the turbidity of the water and shading results.   The microbes absorb sunlight and block its penetration and dispersal in the water.  In effect, this provides sunscreen to the bacteria in the water, including those that might make us ill.

 The bacteria in the water that might cause infection, like Staph. aureus is present almost always, yet their numbers are modest (Goodwin 2012).  They are low from dilution, settling and the UV B of the sun. Problematically, this microbe is more common within the shoreline sand.  Within the sand, it is fully shaded from the death ray UV B.

Estimating and Measuring Turbidity
Divers have an intrinsic ability to estimate visibility.  It is the opposite of turbidity.  When diving in familiar waters, they know depths, and when they can see the bottom at 100 feet, they know the "vis” is at least 100.  Then on days when the bottom is not visible at all, it is less than 100, and as they dive down and the bottom comes into view at 50 of depth, the "vis” is 50.  It is not very scientific but listening to the stories suggests something is going on.  Local divers seem to agree the “vis” in Hawai‘i is not what it used to be. 
To be more objective there are simple to very sophisticated methods for measuring turbidity.  A very visual and informative test that is great for science education as well as scientific studies, employees the Secchi Disc. Merely the disc is lowered into the water on a calibrated rope or field-measuring reel to a depth at which the disc is not visible.
 In the photo, the discs are all at the same depth, but the visibility is very different.  The discs are readily homemade and equivalent to the commercial discs (http://www.instructables.com/id/How-to-Use-a-Secchi-Disk-to-Measure-Turbidity-in-a/).
Light penetration is the least in the right photo.  The same can be said for the UV B.

A nephelometer is a more sensitive measurement.  In this device at water sample is put into a special test tube and inserted into the device that measures the amount of light that passes through the water and the corresponding Turbidity Unit or NTU value displays on its screen.

The State of Hawai‘i uses a Nephelometer in its beach-monitoring program. At most beaches on the islands, there are significant turbidity problems.  On the Kona side of Hawai‘i Island, for example, virtually all ocean monitoring sites have excessive turbidity to the extent that it exceeds Federal and State Standards (https://health.hawaii.gov/cwb/files/2013/05/Draft-2016-State-of-Hawaii-Water-Quality-Monitoring-and-Assessment-Report.pdf).
The data indicate that waters from Miloli‘i in the South to Māhukona in the North have turbidity exceedance.

Turbidity is Sunscreen for Germs
In ideal crystal clear waters, UV B can effectively penetrate only a foot or so.   The effective kill rate is a function of the UVB power dose and the duration of exposure.  On clear days the UVB at the beach impacts the surface layer of the water for hours each day.
 Simply said, the cloudiness of the water reduces the dose to the extent of the cloudiness or turbidity. Reduced dose means less efficient bacterial inactivation. 

In the figure to the right UV kill off of E. coli decreases significantly as the decrease of light transmission or penetration also decreases (Deller 2006).  At 86% UV transmittance and 30 minutes exposure, almost 100% of the E. coli perish.

 While this is illustrative and shows the importance of UV B penetration in seawater, it is not bacteria that cause most of the GI symptoms in ocean users. Rather, human enteric viruses are the most common cause of GI disease in general and in ocean recreationists as well. In Hawaiian waters in the dry season, swimmers risk of GI disease was most significant in waters with enteric virus present (Viau 2011).

Thus it is important to review the ability of solar UV B to the latent enteric virus in marine waters rather than the place too much importance on the indicator species like Enterococci.  Many studies reveal Enterovirus can be present in marine waters that contain low and non-actionable levels of the official indicator bacteria. Viau reports no association between the presence of the indicator genus Enterococci and enteric virus.  The team did find a GI disease association with septic system density in the Hanalei Kauai watershed.

Solar UV B inactivation of bacteria and virus in the figure below suggests the viruses are more resistant to the detrimental effect of UV B radiation.  Since viruses are not metabolically active outside the target host cell (humans) their resistance is consistent with the decreased metabolic functions of latent virus. 

In the chart to the right, the two lower lines represent the bacteria E. coli and Enterococci (Amed 2014).  The upper lines represent virus including Adenovirus. This virus is associated with upper respiratory infections.  

The data indicate that the viruses are indeed more resistant to the ambient UV B and take about 8 to 9 days to reach levels associated with lower risk. The UV resistant adenoviruses remain above100 virus particles per 100 ml of seawater at 14 days.

Take Away Message

Solar UV light is a very significant microbial biomass regulator of the world’s oceans.  In the tropical nearshore regions, Solar UV B under pristine conditions will limit the numbers of pathogens in seawater that have the potential to cause human infections and harm.

As greater volumes of wastewater migrate to the sea increasing numbers of pathogens, and nutrients will occupy the nearshore waters.  The resulting nourishment of the marine phytoplankton will continue the trend of increasing turbidity.  As turbidity becomes more widespread and consistent, solar UV B inactivation of pathogenic microbes is likely to decline and result in greater exposure and risk to resident ocean users and tourists.

From the side of caution, we must assume turbid waters have increased risk.

We must embrace the reality of this system and cease “punting the tin down the road." We must act on the knowledge that human source nutrients detrimentally nourish the marine phytoplankton. They in turn screen the microbes from the sun, which then fail to be inactivated and create a more significant risk to human health.  We have the ability and remedies, but what about the will?

Ahmed, W., et al. "Relative inactivation of faecal indicator bacteria and sewage markers in freshwater and seawater microcosms." Letters in applied microbiology 59.3 (2014): 348-354.

Deller, Sigrid, et al. "Effect of solar radiation on survival of indicator bacteria in bathing waters." Central European journal of public health 14.3 (2006).

Goodwin, Kelly D., et al. "A multi-beach study of Staphylococcus aureus, MRSA, and enterococci in seawater and beach sand." Water Research 46.13 (2012): 4195-4207.

Lau, Leung-Ku Stephen, and John Francis Mink. Hydrology of the Hawaiian Islands. University of Hawaii Press, 2006.

Maraccini, Peter A., et al. "Solar inactivation of enterococci and Escherichia coli in natural waters: Effects of water absorbance and depth." Environmental science & technology50.10 (2016): 5068-5076.

Noble, Rachel T., Ioannice M. Lee, and Kenneth C. Schiff. "Inactivation of indicator microorganisms from various sources of faecal contamination in seawater and freshwater." Journal of applied microbiology 96.3 (2004): 464-472.

Viau, Emily J., Debbie Lee, and Alexandria B. Boehm. "Swimmer risk of gastrointestinal illness from exposure to tropical coastal waters impacted by terrestrial dry-weather runoff." Environmental science & technology 45.17 (2011): 7158-7165.

Yamahara, Kevan M., et al. "Occurrence and persistence of bacterial pathogens and indicator organisms in beach sand along the California coast." Applied and environmental microbiology (2012): AEM-06185.

Sunday, July 1, 2018

Problematic Nitrogen?

Problematic Nitrogen?
R.H. Bennett Ph.D.
Applied Life Sciences LLC

Nitrogen is a fundamental element like Carbon, Oxygen. Nitrogen is a problem, how? It can neither be created nor destroyed but only changed in form (Law of the Conservation of Matter Antoine Lavoisier 1785).  All the nitrogen that ever was still is.  There will be no more or no less. So how can it be a problem? We shall see it's a problem of distribution and chemical form.
 Nitrogen (N) is about 16% by weight of all amino acids and proteins.  Amino acids and proteins contain the elements of Carbon, Hydrogen, Oxygen, and Nitrogen (some include Sulfur) If amino acids don't have nitrogen they would not be amino acids and there would be no proteins and no life, period. Proteins are muscle, skin, enzymes, hormones and more. https://ghr.nlm.nih.gov/primer/howgeneswork/protein
The human species goes to great extent to secure protein in the diet.  Entire lifestyles and economies are predicated on the acquisition of protein.  The human diet must have protein, be it soy, legumes, beef, dairy, fish, and more. The adult diet requires about 46 to 70   grams of protein each day depending on body weight and exercise level. https://www.webmd.com/food-recipes/protein
Imagine the mass of protein that is consumed in Hawai‘i every day.  It is here that the law about the conservation of matter is neither created nor destroyed; the law of physics comes in.   Proteins get digested, degraded, and metabolized.  Proteins are broken down, and the nitrogen remains and must be excreted continuously otherwise the excretion form of nitrogen, urea builds up in the blood and will become very toxic in short order. 
All marine life and the occasional human excrete nitrogen directly into the sea.  This low level of N is not harmful but beneficial.  It is the dose that makes the poison when all of us land-based gritters allow the waste N to migrate to the sea.

Protein nitrogen as urea gets excreted in the urine.  Here are the numbers. About 91% of the nitrogen consumed is excreted in the urine.  The balance is lost in the feces and sweat (Bingham 2003, Dal Porto 1999).

The Fate of Urine Nitrogen (Dal Porto 1999)
Elements (g/ppd)
Urine + faeces
Organic carbon
Wet weight
Dry weight
Nitrogen in urine is in the form of urea.  Under the effects of environmental bacteria, urea is quickly converted into ammonia.  We have all smelled ammonia in urine left to “mellow” in the toilet bowl.   Once flushed the urea and ammonia is again acted on by bacteria that convert ammonia to nitrate.  This process is called mineralization.   Nitrate is salt and entirely water-soluble.  Nitrate is very stable and not altered in form again until utilized by microbes and plant life.
Nitrogen Accumulation in the Receiving Waters: From the Table to the Sea

 Nitrate by Another Name: Fertilizer
 Nitrate may sound familiar.  Go to the garden shop, and you can buy big bags of nitrate in one of many formulations.   Take it home carefully spread it on the grass and plants and walla; they grow better, faster and greener.  Nitrogen in the nitrate and other forms is a fertilizer that plants require for growth and survival.  So too, nitrate fertilizes aquatic plants and microscopic phytoplankton that live in the water.
Let's go back to the toilet and follow the N.   Not long after the flush, most of the N is urea and quickly converted to the nitrate form.  Both urea and nitrate readily dissolve in water.  The Black Water or sewage flows into the cesspit, septic leach field or wastewater treatment plant.  The nitrate remains unchanged for the most part and flows wherever the wastewater goes.
So where goes the wastewater?
On its way to onsite disposal or the regional treatment plant, it flows in pipes, and these pipes can leak.  Sewage water can leak out, and groundwater can leak in when the pressures allow.  Thus some nitrate can escape and flow to water.
 Once discharged from onsite disposal, a cesspit or septic system wastewater flows downslope along the paths of least resistance until it finds its level and that means groundwater, a stream, including lava tube flows and ultimately to the shore.  All along this journey including a very short few days or a long journey of years the water and its nitrate is unaltered by time.   There are some people with official titles that tell us that all waste material is broken down in the “soil."   The problem is such a claim defies that law.  It is the Law of Conservation of Mass says we can only change the form of N.  N is indestructible.   We shall revisit how a change of form can work in our favor.
Zoom up to about thirty thousand feet and look down at our island.  See all the homes and know that all of the homes have an OSDS (on site disposal system) or it is connected via a sewer line to a WWTP (wastewater treatment plant), and all of the urine N flows there.   From there it flows wherever the water goes.
 Is this a big deal?  Yes, let's do the numbers again.
According to that State of Hawai’i, there are about 59,000 OSDS in use right now on Hawai‘i Island (Whittier 2009).  Applying the watershed studies of Reay (2004) and others, the N in the form of DIN (Dissolved inorganic Nitrogen) ranges from 5.7 to 10.7 kilograms (2.2 lbs. per kg) per household per year.   This estimates that somewhere between 740 thousand to 1.4 million pounds of N are flushed into the groundwater connected ocean environment in Hawai‘i Island every year.    To conceptualize this, let's call it 1 million pounds per year.
If this much N was contained in 25 lb. bags of fertilizer such as Ammonium Sulfate (25-0-0) that would be 4 million lbs. of fertilizer or 40,000 bags.  The site of such dumping into the island shores would be a scandal of unparalleled proportions.  That is what is happening along the coasts of this island every year.  It is simply out of sight and out of mind.
 The myth that elevated ocean nitrogen levels are due to Kiawe Trees is now debunked.  Debunked by the mass balance calculations provide above and confirmed by N isotope studies conducted by Dailer on marine algae in our waters (2010).  The N isotope data confirms its human waste origins.
What all this Nitrogen does to the oceans
Tropical waters are oligo-trophic. By that oceanographers mean the water contains few nutrients.  Those that have ever had an aquarium are all too aware of what happens when few nutrients become too many.  Water gets cloudy, often green and a water change for the aquarium is the only remedy.
Our ocean is no different, but the water change part is tricky.  Water change in the sea can occur when a region is subject to significant currents.  The problem being near shore large currents are far less common.  The science of Bathymetry reveals the complexities of ocean currents and the notion that the oceans, especially near shore are uniformly mixed is not supported by the scientific data.  Sorry, apologists, the solution to pollution is not dilution.
 Over the last decade or two monitoring data of the nearshore waters clearly, indicate the island ocean water is increasingly turbid.  Divers regularly comment on the decrease in visibility along our coasts.   Just like the aquarium, nutrients nitrogen and its partner phosphorus from human activity flows to the sea, nourishes microscopic plants called phytoplankton, and they cloud the water (Rinquet 2005).   This is most obvious in narrow bays and inlets like Keauhou Bay.   The turbidity is well documented and most evident in the innermost bay waters.  Turbidity is the reason that most of our beach waters are Federally Listed as Impaired by the EPA.
This photo was taken many years ago in Keauhou Bay not far from the boat docks.  Visibility was a matter of inches in the summer of 2007.  Note the high turbidity and greening of the water.  Land use here is high-density dwellings (some sewered) and golf courses.
An extensive study of Keauhou Bay by Dr. D. Mihalka (2015 unpublished data) confirms the turbidity for the inner reaches of the bay.
Coral Takes A Nitrogen Hit Too
Most people aware our coral reefs are very important to Hawai‘i.   From the ocean's nursery to the visual beauty that attracts tourist’s worldwide and more, the reefs are Hawai‘i.  The value of Hawaiian coral reefs is at least $360 million per year (Cesar 2004). Given itʻs economic, social and cultural value, many argue investment in coral reef protection and conservation is more than justified.
 We are painfully aware the reefs are in decline. Warmer waters and increased acidity is killing corals, some more dramatically than others. Carbon dioxide from the combustion of fossil fuels insulates the earth trapping heat.  Dissolved in water carbon dioxide forms carbonic acid.
 There has been scientific concern that overnutrition of the oceans is also harming corals.  Recent research on the corals of Kaneohe Bay confirms our fears.  Nitrogen acts synergistically with elevated temperature and acidity to decrease the mineralization of corals (Silbiger 2018).  To be simplistic, corals are losing calcium and not gaining it as growing corals do.   Human activities have created the perfect storm to degrade corals reefs slowly and along with them all the benefits they provide to the island ecosystem, the oceans, and the lifestyle and economic vitality of Hawai‘i.
We have scant policy and action about waste nitrogen.
The consequences of human activities and nitrogen released into the environment are well documented (Vitousek 1997).  He states, nitrogen from human activities “caused changes in the composition and functioning of estuarine and nearshore ecosystems and contributed to long‐term declines in coastal marine fisheries."
In 2008 the National Academy of Sciences, Engineering Challenges report identified the critical need to resolve the mismanagement of nitrogen and provided preventive and remediation recommendations.  Those recommendations never found their way through Congress and into policy.

The chasm between science and policy is vast.   Congress and the Hawai‘i Legislature are loath to address this problem since it will impact almost everyone’s pocketbook.   As a society, we have exploited and reaped financial rewards for a fundamentally no cost nutrient disposal into the environment.  The federal subsidies for urban waste management infrastructure are gone, except for a modest loan program.  
There is one program and policy in the US Clean Water Act (CWA) called TMDL or Total Dairy Maximum Load.   Its purpose is to mitigate pollutant exceedances. For all “Impaired” water bodies with elevated nitrogen levels, the law requires TMDLʻs. However, these programs are not funded by the CWA and on Hawai‘i Island, we have none. None, even though at least 12 nearshore waters are listed as “Impaired” due to nitrogen. Many listed sites are on the ninth anniversary and mitigations remain to be proposed
The EPA delegates authority to the state to administer the CWA.  Its provisions are not discretionary.  Just the same the State refuses to require TMDLʻs for impaired coastal waters of Hawai‘i Island.   As citizens, ignoring Federal Law has dire consequences. The state. however is let off the hook, to the detriment of our resources.
Nitrogen Changing Form to the Rescue
Remember the law, Conservation of Mass?  We cannot destroy nitrogen, but nature changes its form all the time.   There is something called the Nitrogen Cycle, and its form changes naturally as it must.
In water, nitrate excess is the problem.  So how do we get it out?  Converting nitrate to something else chemically is possible but on a watershed scale impractical and cost prohibitive.  However, at the site of nitrate formation, nature shows a way.
Denitrification is the solution. It occurs naturally in wetlands. This environment provides a niche for bacteria that need very little atmospheric oxygen.  Their microbial metabolism still needs some oxygen.   So bacteria that can grow in the absence of dissolved oxygen in water can strip oxygen from compounds that carry it.  One such compound is nitrate.   Each molecule has three oxygen’s attached to it.  The anaerobic bacteria can strip off the oxygen’s and in so doing two atoms of nitrogen immerge as the gas N2.  The gas floats away and joins the N2 in the atmosphere.  This process is bacterial denitrification.

In Westbrook CT, they are testing a modified septic system leach field, expected to remove about 64% and more of the nitrogen using this natural process.  It is not likely to add much cost to a new septic system.  It is a simple 12-inch layer of soil and sawdust or any other finely ground source of plant cellulose.  The cellulose is a carbon source for the denitrifying bacteria.  In similar versions with a greater anaerobic area, researchers report a 90% reduction in nitrate nitrogen.   Note the nitrogen gas returning to the atmosphere.   It makes up about 80% of the air we breathe and it is NOT a Greenhouse Gas.
 We have begun collaborating with researchers at Stony Brook University and aspire to demonstrate this simple technology for Hawai‘i.   There will be more on this breakthrough as we demonstrate it here.
Now that the box is broken wide open, it will be easier for folks in Hawai‘i to begin thinking outside of it and take action.
Our keiki and the corals will thank you.
Malama Pono
Bingham, Sheila A. "Urine nitrogen as a biomarker for the validation of dietary protein intake." The Journal of nutrition133.3 (2003): 921S-924S.

Dailer, Meghan L., et al. "Using δ15N values in algal tissue to map locations and potential sources of anthropogenic nutrient inputs on the island of Maui, Hawaii ‘i, USA." Marine Pollution Bulletin 60.5 (2010): 655-671.
Del Porto D, Steinfeld C, 1999. The Composting Toilet System Book, Center for Ecological Pollution Prevention, Concord, Mass.; Drangert J-O, Bew J, Winblad U, 1997. Ecological sanitation: Proceedings from Sida Sanitation Workshop, Balingsholm, Sweden.
Cesar, Herman SJ, and Pieter van Beukering. "Economic valuation of the coral reefs of Hawai'i." Pacific Science 58.2 (2004): 231-242.

Laws, E. A., et al. "High phytoplankton growth and production rates in oligotrophic Hawaiian coastal waters1." Limnology and Oceanography 29.6 (1984): 1161-1169.

National Academy of Sciences. Grand Challenges for Engineering. In: National Academy of Engineering Summit Series - Face the Challenge National Academy of Engineering (NAE). 2008.

Ringuet, Stephanie, and Fred T. Mackenzie. "Controls on nutrient and phytoplankton dynamics during normal flow and storm runoff conditions, southern Kaneohe Bay, Hawaii." Estuaries 28.3 (2005): 327-337.

Silbiger NJ, Nelson CE, Remple K, Sevilla JK, Quinlan ZA, Putnam HM,
Fox MD, Donahue MJ. 2018 Nutrient pollution disrupts key ecosystem functions on coral reefs.
Proc. R. Soc. B 285: 20172718.
Vitousek, Peter M., et al. "Human alteration of the global nitrogen cycle: sources and consequences." Ecological Applications 7.3 (1997): 737-750

This is published with Commons Attribution and may be used freely.  Please cite as RH Bennett PhD, Problematic Nitrogen, Healthy Hawaiian Oceans www.h20kona.org