Expert warns against recycled water
By Peter Williams
May 11, 2007
RECYCLED waste water should be used for drinking only as a last resort, an infectious diseases expert said today.
Several Australian states and the ACT are considering the use of recycled water as a response to critical shortages.
Professor Peter Collignon, director of infectious diseases and microbiology at ACT Pathology, told a senate inquiry the water would be better used for non-drinking purposes.
“I think we should recycle as much as possible. My viewpoint is, that last option should be putting it into our drinking water,” Prof Collignon said.
“We should find all other ways of using water for irrigation, watering our ovals, all those things so that we have as pristine as possible the water we’re using for drinking.”
Prof Collignon said purifying water of sewage had historically been a major cause of public health improvement.
“We’re going to now, instead of separating it, physically put it back in,” he said.
“I think that’s a major step that really requires a lot of thought before we start doing that.”
He said the reverse osmosis process used in the proposed recycling had been shown not to completely remove salt.
“If it leaves 1 or 2 per cent of salt, why can’t it leave 1 or 2 per cent of viruses?”
Prof Collignon was giving evidence at a Senate inquiry into southeast Queensland’s water crisis and the proposed Traveston Dam.
Queensland Premier Peter Beattie has vowed to go ahead with recycling waste water without submitting the proposal to a referendum.
The ACT Government has a similar plan for Canberra.
While Singapore is often cited as a user of such water, Prof Collignon said it was used only for industrial purposes.
He said the only other place in the world using it as drinking water was the Namibian capital of Windhoek in southwest Africa, where the alternative was worse.
The head of the French company that will manage the Queensland project has also said recycled water should first be used for non-drinking purposes.
Veolia Water chief executive Antoine Frerot told Britain’s Financial Times last month that industry and irrigation should use treated waste water instead of tap water.
“That would halve the demand for natural water, Mr Frerot told the paper.
“That is what we should do, before talking about drinking waste water.”
Nationals senator Barnaby Joyce said Prof Collignon’s evidence and Mr Frerot’s comments cast doubts over Queensland government claims that drinking the water was safe and done all over the world.
“The whole premise of recycled water saving Queensland works on the belief that you will excrete more than you drink,” Senator Joyce said.
“I don’t think this is physically possible unless you have got a condition that requires immediate hospitalisation.”
stevem
30 March 2007
Recycled water not worth risks
These are his personal views .
One of our most significant public health improvements was removing sewage from water supplies. Human waste contains numerous viruses, bacteria, protozoans and other microbes that frequently cause disease if ingested. While our sewage will be treated so that it is “safe” to drink, the mechanisms being proposed for this all have potential problems with performance. Thus there is a strong possibility that at times we will contaminate our water supply with disease-causing micro-organisms.
The ACT has large volumes of unused water. Indeed it is a very large net exporter of water to NSW (about 471GL per year). We also currently have one of the best water supplies in Australia (and probably worldwide) from a safety point of view. Currently no human sewage enters our drinking water in our catchments. We are also very fortunate (and unique) in that minimal domestic animal waste enters the water supply because few farms are in our catchments. Most of our current Canberra water is good enough to bottle!
However, if the pore size is so small, I find it difficult to see how these membranes can satisfactorily work without being frequently blocked by larger waste material. Even if such small pore sizes are used, this will still not remove viruses, which are much smaller. Membranes will also not remove drugs passed in urine and faeces that are not broken down (such as oestrogens).
Safety monitoring is planned, presumably by culturing the water and looking at coliform counts. If coliforms (eg E. coli) are present in the treated water this implies faecal contamination (and thus a failure of the system). However, this type of monitoring has problems. Around the world numerous outbreaks with water contaminated with viruses and Cryptosporidiosis have occurred despite low or zero coliform counts. In addition these indicator bacteria take one or two days to grow and identify.
In Canberra we do not need to recycle our waste-water back into our drinking water supply. The current proposal is for initially 9GL of water per year to be recycled into our dams. On average, however, about 120GL per year has been released from our dams into the rivers as environmental flows (46GL) and as spills (75GL). Spills are when dams overflow which has occurred frequently, even in droughts, with the Cotter dam, because of is low storage capacity. This released water is relatively “pristine” from an infection point of view. Why not find ways to withhold 9GL of this water? Is this not a better option than pumping 9GL of very expensively treated waste-water upstream into our reservoirs when we cannot be assured it will always be free of harmful microbes?
Can’t more water from the Cotter dams be transferred if we still have a shortage of water in the Googong dam? Given on average 75GL of water “spills” per year from our dams, surely the amount transferred could be increased to say 20GL per year and avoid the costs and risks of recycling sewage into our water supply.
That, however, would effectively mean that there is no net increase in the water supply for human use. If we did that we will have spent maybe $100 million or more to process and pump water back into our dams, just to let the same amount of water out again! It makes neither environmental nor economic sense.
There is no rice production in the ACT, which means all this water is being used further downstream in the Murrumbidgee river system. If the rice growers down river from Canberra decreased their water usage by just 1 per cent, that would mean that there would be another 19GL available for the rivers.
It does not appear to make sense to spend huge amounts of money recycling waste water and putting this water back into our Canberra drinking water, when at the same time we are releasing “pristine” water from these same dams for environmental flows especially when this released water is effectively being used mainly for irrigation purposes downstream to produce water intensive crops such as rice.
stevem
The Senate Inquiry into water supply options for South East Queensland heard expert evidence in Canberra today that drinking “purified recycled water” from sewage treatment plants is risky.
“What I see Singapore doing is a sensible use of recycled water – using it for industrial purposes so you can save your drinking water,” Professor Collignon said.
He told Senators drinking recycled sewage water would be defined as a “moderate to high risk” under Australian Drinking Water Guidelines.
Queensland Nationals Senator Barnaby Joyce said professor Collignon’s evidence cast serious doubts over the Beattie Government’s claims that drinking recycled sewage water was safe and was done all over the world.
Senator Joyce said: “Veolia is one of the world’s leading operators of recycled water schemes with over 100 plants operating in France, Honolulu and Durban, South Africa. Yet none of them are for drinking.”
“The whole premise of recycled water saving Queensland works on the belief that you will excrete more than you drink. I don’t think this is physically possible unless you have got a condition that requires immediate hospitalisation,” Senator Joyce said.
“Recycling to a dam that is five percent full has huge question marks over it because of the presence of heavy metals and other toxins,” Senator Joyce said.
“To be positive, we must come up with a primary source of new water before Brisbane runs out which could be as early as the end of next year.
“We may have to bring in water from an external source. Although this will mean absolutely severe restrictions, it is better to plan for it now, build the infrastructure for receival and reticulation now than to stay on board the aimless progression to the ultimate water train wreck at the end of next year.
“The people of the south east corner don’t need any more convincing of the lack of management expertise in deputy Premier Anna Bligh’s delivery of a water grid.
“By the time her water grid is completed there will be no water to move around it. Unfortunately Ms Bligh’s record of being completely implausible on all that she does and all that she says, means that her current guarantees are nothing but ashes in the mouth of a parched south east Queensland.
stevem
YASMINE PHILLIPS
22 March 2007
The West Australian page 3
(c) 2007, West Australian Newspapers Limited
Internationally acclaimed scientists have sparked fears over the safety of drinking recycled sewage, warning that new man-made chemicals and pharmaceutical products could slip through the filtration process, raising the risk of cancer and infertility.
US cancer expert Steven Oppenheimer told The West Australian the “toilet-to-tap” process should only be considered as a last resort, likening drinking recycled water to playing “Russian roulette” with human life.
“The world’s scientific community does not and will not know all the toxic agents and carcinogens that may be able to make it through the indirect reclaimed water process to drinking water,” the director of cancer and development biology at California State Northbridge University said.
Professor Oppenheimer’s claims were backed by University of Newcastle Professor John Aitken, whose research concluded that some by-products found in recycled water could damage a man’s sperm and promote cancer growth.
Professor Aitken’s concerns were outlined in a booklet which was distributed this week to 400,000 households in Brisbane by activists who are opposed to the Queensland Government’s plan to use recycled sewage water. The brochure detailed the results of a British study which found a third of male fish in English rivers were changing sex because of “gender bending” pollution in 2004.
Britain’s Environmental Agency believes the number of British couples struggling to conceive had increased 55 per cent in five years to one in six, a trend blamed on sewage mixing with drinking water.
Australian Water Association chief executive Chris Davis agreed it was impractical to test for every synthetic chemical in treated waste water.
stevem
Prescription Drugs Found in Fla. Sharks
Published Sunday, June 3, 2007
SARASOTA - Sharks in one Florida river are getting a dose of human medicine, and now scientists want to know if it’s a prescription for trouble.
Scientists recently found traces of prescription antidepressants, cholesterol-lowering drugs and synthetic estrogens in the blood of young bull sharks in the Caloosahatchee River on Florida’s southwest Gulf Coast.
This summer, they’ll study the issue more widely. On Friday, scientists with Mote Marine Laboratory fished for bull sharks as part of research to find out what drugs the sharks encounter most and whether the doses are large enough to alter how they behave and reproduce.
The sharks come into contact with treated waste water which includes traces of the medications previously identified as the cholesterol-reducer Lipitor, various antidepressants such as Prozac and Zoloft, synthetic estrogens used in birth-control pills, and anti-inflammatory drugs such as Celexa.
The Caloosahatchee receives treated wastewater from several sewer plants and passes by numerous septic-system dependent communities.
And while the water is treated, and treatment systems are good at removing bacteria, they are not designed to remove drugs, which may have been flushed down the toilet or excreted by humans taking the medications.
To get a sense of the effect of drugs on sharks over time, scientists are tagging them with chemical-absorbing discs.
The discs will absorb chemicals from the environment and be compared with chemical quantities in the sharks’ blood. That will help scientists estimate how well the sharks absorb the chemicals they encounter.
“We don’t really have a good sense of how much is in the environment and we have certainly very little information on what the impacts are,” said Jim Gelsleichter, of the Mote Marine Laboratory, who is leading the study.
Bull sharks are a good species to study because young sharks spend a year swimming in brackish waters and therefore come into greater contact with human contaminants, including treated waste water.
View Printer Friendly Version