Hidden Enemy

The Invisible Enemy – An Allegory
Part one

Before time was, he was. The only living thing on the Earth, single of cell, ignorant of Darwin, he has lain dormant, quiescent, unchanging, for 3 billion years. The first and chief producer of organic matter and the first to release elemental oxygen into the primitive atmosphere, he was responsible for evolution itself and the very existence of mankind. He and his kind lived everywhere, on land and in the oceans and fresh-water lakes. They lived in the extreme conditions, from minus 60C to plus 85C, where nothing else lives, from icy arctic currents to volcanic rock. Moreover, they still live the same existence.

For all these billions of years, they have harmed nothing and no one. Now they feel themselves under attack from the very thing they gave life to - mankind. Their worlds are being destroyed faster than ever before and their waters poisoned. Nevertheless beware, they are invisible and they cannot move themselves, yet they can harness the elements, wind and water, to transport them wherever they want to go. Nowhere is safe from their invasion. In addition, they are on the attack!

Humans, in what they thought was their safest environment - a hospital, are mercilessly killed with their own drinking water, or their air conditioning! Untold millions of tons of fish are killed in the world's oceans. Thousands of human communities destroyed throughout the land, as their livelihood and basic food disappears under the assault. In the wetlands of Siam, thousands of water buffalo and cattle fall fatal prey to the relentless attack. In Australia, cattle and sheep die in their thousands. In the USA, thriving communities of shell fishers are seeing their communities ravaged by the encroachment of this savage retaliation. From satellites in space, we see the enormous explosion of their dread influence (red tides). Whilst in the UK, a cosseted public squirms at the loss of their recreational waters, ignorant of the greater danger poised at their taps.

Who are these creatures and why should we fear them? Because we know almost nothing of our enemy; we don't know what 'makes them tick'; we don't know their motives. We cannot even begin to guess how many there are. New cohorts of their army are discovered daily. Moreover, we have no response - no antidote to those weapons of theirs that we already know.

Now, read on. Read, mark, and inwardly digest!

Know Your Enemy!

We are engaged in a war, but this is a different kind of war. We have to admit our culpability and put right those things we have done wrong and stop those things we are doing that are precipitating this conflict between arrogant mankind and his environment, if only because it's a war we can't win! First, let's see what little we know of the enemy in this, his offensive campaign.

'Blue-green algae' is the commonly used (non-scientific) term for several types of bacteria (Cyanobacteria) that sometimes impart a blue-green tinge to water, both inland and marine. As in any war, three of the most common have been given nicknames by scientists, 'Anna', 'Fanny' and 'Mike'. For the moment, their real names don't concern us. They occur naturally in our waterways and are part of the water environment. They are extremely small organisms, their species only recognisable under a high-powered microscope; they may occur as single cells, or colonies of filaments, coils and 'clumps' of cells. When present in high concentrations, colonies of blue-green algae can often be seen with the naked eye: they may resemble fine nail or grass cuttings or take the form of small irregular bunches or pinhead-sized spheres.

In an open-water environment, they can form blue-green scums on the surface, now getting to be a regular feature of seaside, lakes, countryside and urban parks and gardens. This is their battlefront. A severe contamination will appear as a continuous 'mat' on the surface of the affected water and may extend some distance below it. When certain species in such high concentrations are decaying, the dying cells release their deadly toxins. They cause the water to taste bad and give off a malodorous smell, by releasing poisonous gas. They are harmful to the health of humans, as well as animals. (Those toxins of algae, which once dominated the recreational waters of Hampstead Heath, for example, are more virulent than the venom of the cobra).

In 1996, in a Brazilian hospital, over 50 dialysis patients died as a direct result of these toxins invading the public water system whose water was used for their treatment. Although no further human death has been recorded as directly attributable to blue-green algae until 2003, when a young boy died after swimming in a blue-green algae contaminated Milwaukee golf course pond, there are now many documented reports of acute and chronic human illnesses. But the main occurrence of human illness caused by these cyanobacteria still comes from the ingestion of contaminated drinking water. Similarly, throughout the world, significant animal and fish losses have been caused by toxic blue-green algae. Currently, in the UK, an increasing number of dogs are suffering because of ingesting blue-green algae after swimming in contaminated waters.

Questions have been asked in the EEC about the possibility of these toxins entering the water supply, but no steps have yet been taken in the UK, to include them in Water Regulations, which would make them, statutorily, part of water analysis protocols. One, microcystin, has a guideline 'threshold' published by the World Health Organisation.

What is an algal 'bloom'?

Under favourable environmental conditions, blue-green algae will increase their numbers rapidly, causing population explosions. 'Bloom' is commonly used to describe an increase in algal numbers to a point where they discolour water, form scums, produce odours and reduce water quality for human and live animals use. They most commonly occur in warm, calm, shallow bodies of water, ponds, reservoirs, etc., where the water is hard, alkaline and rich in nitrogen, phosphates, carbonates and organic matter.

When environmental conditions are such as to attract us to their battlegrounds, then their noxious properties can cause severe damage to a range of happy water users. Algal blooms are aesthetically unpleasant. More importantly, the toxins of some species have the very real potential to cause sickness and death in humans and animals.

Blue green algae cells can group themselves into different shapes, according to their species. They can remain as single cells or form colonies of filaments, chains, coils and so on. Blooms (or scums) form when large numbers of algae float to the water surface, the tiny gas bubbles in their cells allowing them to float to the surface for sunlight or sink to the bottom to feed. This partly explains why a bloom can appear, disappear and reappear quickly even during a single day. Wind stirring also plays an important part in this process. Wind pushes the floating algae across the water concentrating scums against leeward shorelines or obstructions.

At the beginning of the bloom, scums can vary from paint-like accumulations at water surfaces to small green floating dots. Scums are often green or blue green, but can also be white, brown, blue, yellow-brown or red. They can also camouflage themselves and can be mistaken for common plant life (duckweed, or spiro gyra, for example), which is inoffensive. Wind movement and water flow or other species of blooming algae can cause swirling patterns of a mixture of these colours. One species doesn't always dominate the water to the exclusions of others, although if the conditions are right, it can happen.

The toxins of the algae are not poisonous to each other, only to higher forms of life. Their toxins increase their virulence through concentration in the food chain, ending in fish, turtles, alligators, shellfish, mussels etcetera, and should we eat any of those, in us, where they can seriously harm us or even kill us!

Blooms occur because environmental conditions are suitable for their growth. These conditions include increased levels of phosphorus and nitrogen in the water, chemicals (produced by man) toxic to organisms that eat algae, lack of fresh water inflows, temperature stratification in the hotter months, murkiness (turgidity), removal of other vegetation that might compete for light and nutrients, fish activity, strong sunlight and high air and water temperatures.

They are made even more suitable by unthinking, intolerable and unclean human activities in the catchments of the waters and in the waters themselves. Although normally very visible to the human eye, the blooms of some species can exist below the surface of the water. (They are capable of underwater warfare, too!) The presence of a bloom is identified by environment agencies as a threat to:
1. Public health... when the water may be used for drinking and domestic purposes.
2. Public health... when a natural water body may be used for recreation.
3. Animals... where the water is a natural body, e.g. lakes, ponds, etc.

How to combat the enemy

Algal Alerts - What and where are they?

A nation at war has always warned its citizens of dangers from the enemy, usually audibly. ALGAL ALERTS are public warnings, very common in Australia, parts of the USA, Canada and most European countries, which should be issued by health authorities. Responsibility for these lies fairly and squarely, not to mention lawfully, with the owners of the waters affected, based on their assessment of the risk from toxic blue-green algae to users of public waters.

These Alerts should be based on:
1. Effects on regular users at and visitors to the waters.

2. Consideration of the area, volume and location of affected water in relation to potential water users, and other factors such as whether and where water is flowing and mixing, the wind direction and speed, weather forecasts, the season and, most importantly, the history of blooms at the site and recorded instances of related illness or death in human or animal.

3. Identification of algal species. (The only sure way to identify algae is to have an accredited laboratory examine a water sample.)

4. Determination of the concentration (numbers and size) of algal cells in the water, and its toxicity.

5. Aesthetic considerations.

Why we need Algal Alerts

In recent years, the theatre of the war has grown ever larger. There has been an increase internationally in the reporting of noxious blooms in inland fresh water as well as marine environments, with many badly affecting water use. To try to ensure the health and safety of water users and their animals, continual monitoring of water sources and other public waterways for the presence of the enemy is vitally necessary.

If blue-green algae numbers increase above certain levels, the appropriate authority should issues ALGAL ALERTS via the media (local radio, television, newspapers and on its own web-site), as is commonly done in other countries. Water users can then take appropriate action themselves to avoid the problems associated with a blue-green algal bloom. Assessments of the risks to human and animal health from blue-green algal blooms are likely to be made for different purposes by different "stakeholders". Stakeholders must include individuals, for their interests as employees, parents, and pet-owners (particularly dog owners) or in connection with their recreational interests.

However, despite scientific evidence to the contrary, ("freshwater algae are rarely toxic"), environment agencies prefer to err on the side of caution and treat all blue-green algae as toxic, no doubt due to the seriousness of some of the illnesses that may be caused and the absence of any antidotes. This also obviates the ‘need' for toxicity testing. They advise accordingly, which results in facilities being closed when they should be open and open when they should be closed. Cynics would no doubt say that preclusion of legal claims is also a factor in, if not the crux of, any decision to close facilities for freshwater recreation.

Algal Alert Levels?

Blue-green algae ALERT LEVELS should be a guide to the state of a bloom. They should be based on water samples, which, however, may not represent the full picture. Conditions change hourly, during the day, from day to day, and over short distances within the affected water. Alerts should be treated more like a weather report rather than a doctor's diagnosis. A typical ALERT format (from an Australian example) should be similar to the following:

BLUE-GREEN ALGAE (CYANOBACTERIA) - LOW LEVEL ALERT

What this means: Blue-green algae are not present at bloom levels. However, water contains 500 to 2,000 cells per millilitre, sufficient numbers favourable for rapid algal growth. The environmental conditions are also favourable for such growth. Some species of algae can cause taste and odour problems even at low cell concentrations. Bright green flecks (algal clumps) in affected water mean there is a strong case for a MEDIUM ALERT.

What YOU must do:
1. If humans or animals ingest the contaminated water, watch for signs of illness (nausea, gastroenteritis, and more.).
2. You must report any symptoms to you GP, telling him of the probable cause. (Contact with or swimming in contaminated water).

BLUE-GREEN ALGAE (CYANOBACTERIA) - MEDIUM LEVEL ALERT

What this means: Musty or earthy smells common. Blue-green algae are visible as green flecks in a bucket or glass jar. Water contains 2,000 to 15,000 cells/mL. There are enough blue-green algae present for a population explosion. Water, temperature and movement conditions are suitable for algal growth and if they remain this way, a HIGH ALERT may result in a few days.

What YOU must do:
1. If humans or animals ingest the contaminated water, watch for signs of illness (nausea, gastro-enteritis, and more.). You must report any symptoms to you GP, telling him of the probable cause. (Contact with or swimming in contaminated water).
2. Use alternative drinking water supply for animals
3. Carefully clean fish removing all gut material.
4. Do not eat mussels or shellfish.
5. Avoid scum when collecting water for any purpose.
6. Keep animals away from leeward shoreline of affected water body. Pets may be sensitive to algal toxins.
7. If you are sensitive to algae avoid direct skin contact with the water.
8. Report Blue-green Algae in public waters to the Heath Authorities or the local council.

BLUE-GREEN ALGAE (CYANOBACTERIA) - HIGH LEVEL ALERT

What this means: "Bloom" conditions apply. Water may have a blue/green tinge and musty or earthy odour. In calm water, scums may form on the surface where they can be blown towards the shoreline. In windy conditions algae may be mixed into the water column and be less visible. Usually, there are more than 15,000 cells/mL of Blue-green Algae present. It is at a stage that algae are most liable to prove toxic to humans and animals.

What YOU must do:
1. If humans or animals ingest the contaminated water, watch for signs of illness (nausea, gastroenteritis, and more.). You must report any symptoms to you GP, telling him of the probable cause. (Contact with or swimming in contaminated water).
2. CHILDREN, DOGS AND OTHER ANIMALS ARE AT PARTICULAR RISK, keep them away from affected areas and provide an alternative water supply for animals.
3. Do not drink untreated or even boiled water from contaminated areas.
4. Avoid contact with, or use of the water.
5. Do not fish from waters where algal scums are present.
6. Do not eat fish from the contaminated waters.

In each case, the alert should list the symptoms that can be expected in the worst case, e.g. ingestion of blue-green algae. These could include some or all those listed below in ''Dangers and Problems..."

Interpreting the sample data, what doe they mean?

The public should be allowed to see a copy of the raw data from the testing of samples. Normally, counts of the algae should be in the number of cells of blue-green algae per millilitre of water (cells/mL). The algal species present should be listed, the 'dominant' alga displaying the highest cell count: This listing of all algal species present is important because the dominant alga may not be the cause of any symptoms that follow contact/ingestion.

The list is also a necessary addition to the historical data that should be kept for each water source. The "Alert" conditions above shows the range of total blue-green algal cell counts of the dominant alga and what they may mean to you. Normally counts in the 'High Alert' range are the most important, however 'Medium Level' counts should also be taken seriously as the bloom may still be developing and before long could be at 'High Alert' if conditions are suitable.

There are other parameters, which should be tested for, if the situation is to be properly monitored and managed. These data also should be public knowledge. (See TOXICITY LEVELS below)

Dangers of and Problems with the Enemy!

Aside from the aesthetic and nuisance problems caused by their appearance, their taints and odours, the worst feature of blue-green algae is their ability to produce toxins (biological poisons) including neurotoxins (which create paralysis) and hepatotoxins (which damage the liver). Most important is the amount of exposure to the toxins.

Some animals are particularly sensitive. Dogs have sensitive noses and lick their fur to clean themselves, possibly taking in concentrated algae. Fish appear externally to be little affected. Fish deaths during blooms may be caused by toxins or by the depletion of oxygen in the water due to the extent of the bloom and by the liberation of hydrogen sulphide and ammonia caused by cell decomposition (which is that nasty smell you get around decaying blooms), or by the clogging of gills. Birds, on the other hand, are known to die in large numbers and species.

At low concentrations, blue-green algae, with the possible exception of Microcystis, may cause no serious problems. At high concentrations, the problems (listed below) may be encountered if animal or human ingests the water. Each year throughout the world, animal deaths are reported due to the toxic effects of blue-green algae and the first human death attributed to blue-green algae in recreational waters was in Milwaukee in 2007.

Human death strongly suggests that the toxins, when present, are a serious hazard to human health, especially when drinking contaminated water, either at the source or from the tap or involuntarily, such as when falling into or swimming in contaminated water.

Health: Adverse Symptoms.
1. Some algal toxins affect the skin and sensitive membranes.
2. Neurotoxins are the most deadly and affect the nervous system.
3. Other toxins affect the liver and may make a person more susceptible to other diseases.
4. Children and those with liver problems may be more at risk.
5. In humans, skin and eye irritation, nausea, headaches, gastroenteritis, diarrhoea, vomiting, and dermatitis may occur.
6. Some people are sensitive to the aerosols of blue-green algae, which can induce hay fever-like symptoms as well as asthma. (These aerosols may be implicated in the spread of 'Legionnaires' disease)
7. Animals and wildlife may suffer skin sensitisation, paralysis, convulsions, liver damage, disorientation, constipation, scours, abortion or even death.
8. Fish, particularly, can suffer severe liver damage, whilst remaining alive.
9. Fish and other aquatic organisms suffer bad health due to extreme day/night fluctuations in water dissolved oxygen and pH, caused by blooms.

Other problems
1. Foul taste and odour to the water.
2. Blocking of filters/sluices NB: The "activated carbon" filters used in a great many water purification systems do not always completely remove all the biological toxins present in the water.
3. Water treatment processes are affected due to chemical changes in the water.

It is likely that the symptoms in humans are under reported. The public, including physicians, are not aware of them or their origin, because the appropriate authority has failed .to inform them. Therefore, they do not connect them to the presence of blue-green algae toxins in recreational or other waters.

There are very many species (over 2000) of Blue-green algae. Some are not known to have any toxins; others have one or more different types of toxin. At the last count, there were only ten taxa containing toxic capabilities. Other algae are capable of forming toxins but do not do so or do not choose to release them. Toxicity may occur for only part of the time or in only part of the bloom, of most of them, little or nothing is at present known beyond their existence.

How long does their toxicity last?

Blue-green algae blooms often persist for several weeks, sometimes months, depending mainly on the weather or water flow. Cooler, windy, cloudy weather or increased flows usually reduce or stop a bloom quickly. When cells die and break up it can take days for nerve toxins to disintegrate and weeks for liver toxins to disappear. It is probably best to wait at least a couple of weeks after a scum forming bloom has gone before using the water for any recreational purpose. Some of the blue-green algal toxins will remain toxic in a dry form on the banks.

Toxicity

The very potent toxins produced by a number of solitary, or colonial blue-green algae, are responsible for an increasing number of water-related poisonings of both wildlife and people worldwide, since the 1970s. The liver toxins of the blue-green alga "Aphanizomenon flos-aquae" (Fanny) are fatal at 9-micrograms per kilogram body weight. This is roughly equivalent to a fatal dose of 1/1000th of a gram of toxin for an adult of 100kg (1/25,OOOth of a gram for a 4kg dog) or slightly more than the potency of cobra venom. Some toxins are tumour promoters and produce cancer in laboratory animals. They block neuromuscular activity, affect the cardiovascular system and cause lesions on the liver.

There was once no way to tell for sure whether water containing algae was toxic or not, unless some of it was actually injected into an experimental laboratory animal. I am sure that many of you would find such an action unethical and intolerable. Happily, this is no longer the case, although it remains the quickest and cheapest method. There are now other methods for the analysis of water samples for some algal toxins. There is no longer any viable reason for not testing the waters' toxicity. Because there are no antidotes to these toxins known to be effective at counteracting their effects, once they have been ingested, this really is of paramount importance.

Researchers apparently understand much of the biochemistry of many of these toxins once they are consumed or absorbed, but not as much about what causes the micro-organisms to produce them and how they can be prevented from flourishing. Pollution with high nutrient runoff, particularly high phosphorus levels, encourages and prolongs the blooms; it also causes blooms to persist in recreational waters, where there is the highest chance of contact by people. The writer has also heard anecdotal evidence that fish are in some way instrumental in causing algae blooms but has not yet come across reports of this phenomenon in the scientific literature, of which there is a huge and abstruse amount.

Notwithstanding all of the above, lest he be accused of an alarmist attitude - genuinely toxic freshwater algal blooms are rare and most cyanobacteria are not harmful. Indeed, a number of Blue-green algae including, latterly, the scourge of the Hampstead Heath's ponds (Aphanizomenon flos-aquae) are readily available in Health Food shops as a dietary supplement. There is a multi million pound business in them worldwide. They are used as a food and in agriculture as animal foodstuffs and to improve crop production (e.g. rice), sometimes in areas where no crops could previously be grown (as in arid districts).

The Strategy for defeat - Taking the war to the enemy

Managing blooms and their expansion

Starvation of the enemy is our best weapon! Algae need three things for optimal growth: light, nutrients and high temperatures. Lowering the nutrients, light and temperature available to the blue-green algae in the water supply will help reduce algal growth. The speed at which water is flowing and mixing is important in controlling light, temperature and nutrient availability to algal cells.
Actions:
1. Water flow through the water system must be improved. In dry periods, flush with clean chlorine-free water. The normal incoming water will be loaded with nutrients. Filter beds of vigorous marginal plants must be planted at the point of inflow. (Phragmites communis is very effective for larger ponds).

2. More oxygenating plants must be grown, essential in the war against algae. (e.g. Lagarosiphon major - Goldfish Weed or Pondweed). They absorb carbon dioxide and mineral nutrients; they compete with and eventually starve out the enemy, blue-green algae.

3. Use floating plants for light control - up to 1/3rd the surface area of the water. This will reduce the light available to the algae. .

4. Surround waters with a vegetation buffer. Bushes and other plants use up and reduce the troublesome nutrients percolating through the soil to the pond.

5. Initiate water treatment measures BEFORE blooms start.

6. Use the "Barley Straw" treatment in the correct, specified, manner.

7. Real-time in-house analysis of water quality parameters by affordable computer process should be used to provide indicators for risk assessment. The affordable computerised systems now available should prove more economically viable compared with consultant or laboratory costs. Could be based centrally, to facilitate use by others, or on site locally.

8. Set up Voluntary water monitoring groups to monitor inland fresh waters on a regular, systematic basis. (The Secchi disc, turgidity, pH tests, water temperature, weather details.). Many inland waters already have associated voluntary groups, which could be utilised. Any necessary skills could quickly be learned and the necessary equipment is cheap. In North America, almost the whole of that vast country's inland fresh waters are monitored in this way! See http://www.nalms.org/

9. If blooms do occur, harvest them (remove them to compost).

10. Re-assess the practice/methods/extent of 'mudding out' of waters that inevitably causes severe ecological damage by removing entirely or severely reducing long established microbial organisms and plants that, by competing with the blue-green algae for nutrients and light, naturally reduce the probability of blooms occurring.

11. Avoid run-off into ponds from fertilizers, pesticides and eroding soil.

12. Most chemicals work to prevent an algal bloom. Water in small ponds can be protected from blue-green algae by dosing with gypsum and alum. These chemicals work by removing phosphorus from the water. In the UK. Algicides can NEVER be used to treat public waters because they may be harmful to the environment and the practice may be illegal.

Arrangements for the management of algal blooms should be documented and published in a local "Blue-green Algae Monitoring and Action Plan". It should include provision for assessing the nature and intensity of algal blooms.
Another difficulty, however, lies in the fact that algae can tolerate adverse conditions such as the complete drying of a pond or cold winter temperatures, and germinate new juvenile filaments when favourable conditions return. They form spores (akinetes), which are induced by cold, drought, lack of phosphate, and low light with lack of nutrients.
Yet another is that algae create aerosols and are airborne in significant numbers at certain seasons.

Propaganda Essential to any war effort

Suggested NationaI/Regional/Local Mechanisms for providing information to the public.

As set out in the relevant provisions of the United Nations' "Convention on Biological Diversity", national authorities and institutional mechanisms must be responsible for encouraging public participation by allowing them access to information on which decisions are based. This should allow for local knowledge and circumstances to be taken into account in risk assessments. Authorities must be encouraged to enter into dialogue with their staff/personnel as well as with the public about their activities.

Suitable methods for communicating with the public:

1. Publish full details, plans, analyses, progress etc. on the appropriate website.

2. Encouraging those with Blue-green Algae in their environments to inform local people, through public meetings, advertisements in local newspapers, posters, adequate warning signs at strategic points, or other appropriate means.

3. Publishing raw data e.g. algae analysis reports by several means.

4. Publishing a newsletter outlining the kind of work that is being carried out with Blue-green Algae, its purpose, and the controls under which it is taking place.

5. Encouraging dialogue between companies and academic institutions working with Blue-green Algae and public interest groups.

6. Electronic bill boarding.

7. Making use of radio and television.

8. Establishing a register of information about the occurrence of blooms and control of Blue-green Algae. Such a register should provide for appropriate safeguards for commercially sensitive information; a summary of risk assessments; evaluations by the authorities or any relevant advisory committees.

9. Giving interested groups the opportunity to comment on proposals to control Blue-green Algae, possibly based on a register of information as outlined above.

10. Any other means appropriate within the local context.

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Now, look out for Part Two, “The Invisible Enemy's "Fifth Column"

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This article is, by and large, not original work. It is distilled from a wealth of information in the public domain on the World Wide Web and a little from UK Government sources not normally available to the general public and from the USA, Canadian, Australian Governments, who are much more forthcoming. It is published and distributed, gratis, in the public interest. Its format and some of the information comes from: "What scum is that? Algal blooms and similar prolific plant growth" by Simon Mitrovic, published by DLWC, 1995, (an Australian Govt. Department), also in the public domain.

My thanks are due to a number of individuals in the Environment and other Agencies and in Academia for freely given advice and assistance. It would be invidious to name them.

Remember -let's be careful out there!

The Invisible Enemy – an allegory © By Mike Garcia 2008

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Monday, 7 July 2008

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