Infectious parasites found in Torres Strait Islands’ water making residents sick
19 July 2018
Torres Strait Islanders believe they are being denied a basic first-world human right to clean drinking water after cryptosporidium was detected in the water supplies of three islands.
The microscopic parasite was found at levels of 2.0 (oo)cysts/10L in a sample tested by Cairns Regional Council’s Water Laboratory.
There is no set guideline value for the parasite in the Australian Drinking Water Standards, but cryptosporidiosis is an immediately reportable infectious disease.
The water test was organised privately by a Thursday Island resident in May, concerned with the lack of response by governments at all levels.
The outcome led to a boil water alert being issued, with a joint Torres Shire Council and Queensland Health statement in June citing “turbidity and a bacterial risk” in the water supplies of Thursday, Horn and Hammond Islands.
Water quality has significantly deteriorated over the past two years, according to residents.
“There’s a dirty colour to the water … people are getting sick, stomach bugs and stuff,” said Thursday Island resident Rita Kebisu.
“We seem to be going backwards into third world standards when we still need to boil our water.”
Queensland Health said Thursday Island’s hospital has seen no unusual levels of water-related illnesses.
“We all put it down to the normal virus going round, a 24-hour virus, you’ve got a bit of diarrhoea, vomiting,” said another island resident, Chi Chi Fujii.
Eight cases of cryptosporidiosis have been reported in the Torres and Cape region in 2018, up from two last year, while there were 23 cases in 2016.
Sinking costs into fixing dirty water
Bad water is also bad for business, especially when you run a cafe like Raphael Gushtaspi.
“Water filters, they’re $80 each, plus the paper filters are $26, and you’re changing them monthly,” Mr Gushtaspi said.
Normally you could get a year out of a high micron canister filter and within four months I’ve got to change it. That’s how much it clogs up now.”
He said the water crisis is also creating unacceptable workplace health and safety issues for his staff and clientele.
“Customers want water, we want water to wash up, to clean, and we don’t want to run the risk of making anyone sick,” the cafe owner said.
No quick-fix to island water upgrade
The Queensland Government has pledged $12 million in this year’s budget for a series of projects to deliver improved water quality on the islands over the next two years.
Opponents are sceptical whether that will be enough to fix issues with undersea pipelines connecting the Horn Island reservoir to Thursday and Hammond Islands.
“All of the system is going to need to be somehow flushed, this is not a small job,” said the Federal Member for Leichhardt, Warren Enstch.
Residents said they also want relief for the cost of accessing clean water during the upgrade.
“How do we manage over two years? Do we get some sort of rebate from the Council because we are buying water every day?” Ms Fujji said.
Local Government Minister Stirling Hinchcliffe said a rebate was unlikely.
“There’s no requirement to use bottled water. There are other solutions which people are advised about, on a regular basis, about boiling water,” Mr Hinchcliffe said.
“That’s not an unusual thing when these unfortunate circumstances occur.”
The ABC contacted Torres Shire Regional Council but no-one was available for comment.
“In recent years, Cryptosporidium has come to be regarded as one of the most important waterborne human pathogens in developed countries. Over 30 outbreaks associated with drinking water have beenreported in North America and Britain, with the largest infecting an estimated 403,000 people (Mackenzieet al. 1994). Recent research has led to improved methods for testing water for the presence of humaninfectious species, although such tests remain technically demanding and relatively expensive.
Cryptosporidium is an obligate parasite with a complex life cycle that involves intracellular development in the gut wall, with sexual and asexual reproduction. Thick-walled oocysts, shed in faeces are responsible for transmission. Concentrations of oocysts as high as 14,000 per litre in raw sewage and 5,800 per litre in surface water have been reported (Madore et al. 1987). Oocysts are robust and can survive for weeks to months in fresh water under cold conditions (King and Monis 2007).
There are a number of species of Cryptosporidium, with C. hominis and C. parvum identified as the main causes of disease (cryptosporidiosis) in humans. C. hominis appears to be confined to human hosts, while the C. parvum strains that infect humans also occur in cattle and sheep. C. parvum infection sare particularly common in young animals, and it has been reported that infected calves can excrete up to 10 billion oocysts in one day. Waterborne outbreaks of cryptosporidiosis have been attributed to inadequate or faulty treatment and contamination by human or livestock (particularly cattle) waste.
C. hominis and C. parvum can be distinguished from one another and from other Cryptosporidium species by a number of genotyping methods. Infectivity tests using cell culture techniques have also been developed. Consumption of contaminated drinking water is only one of several mechanisms by which transmission (faecal-oral) can occur. Recreational waters, including swimming pools, are an important source of cryptosporidiosis and direct contact with a human carrier is also a common route of transmission.Transmission of Cryptosporidium can also occur by contact with infected farm animals, and occasionally through contaminated food.” ADWG 2011
Horn Island (Queensland): E.coli
“Coliforms are Gram-negative, non-spore-forming, rod-shaped bacteria that are capable of aerobic and facultative anaerobic growth in the presence of bile salts or other surface active agents with similar growth-inhibiting properties. They are found in large numbers in the faeces of humans and other warm-blooded animals, but many species also occur in the environment.
Thermotolerant coliforms are a sub-group of coliforms that are able to grow at 44.5 ± 0.2°C. E. coli is the most common thermotolerant coliform present in faeces and is regarded as the most specific indicator of recent faecal contamination because generally it is not capable of growth in the environment. In contrast, some other thermotolerant coliforms (including strains of Klebsiella, Citrobacter and Enterobacter) are able to grow in the environment and their presence is not necessarily related to faecal contamination. While tests for thermotolerant coliforms can be simpler than for E. coli, E. coli is considered a superior indicator for detecting faecal contamination…” ADWG 2011
Torres Dam (Queensland) – Arsenic
2011/12: Arsenic 0.014mg/L (highest level)
Arsenic: Australian Drinking Water Guideline = 0.01mg/L
Arsenic is bioaccumulative and symptoms may take 10-15 years to develop after expsoure at high levels. Drinking water can be contaminated with inorganic arsenic through wind blown dust, leaching or runoff from soil, rocks and sediment. Groundwater sources such as bores will usually have higher arsenic levels than surface water. In major Australian reticulated water supplies concentrations of arsenic range up to 0.015mg/L, with typical values less than
Torres Dam – Queensland – Temperature
2011/12: Torres Dam (Queensland) – Temperature 22C
2011/12: Horn Island Dam (Queensland) – Temperature 22C
“No guideline is set due to the impracticality of controlling water temperature.
Drinking water temperatures above 20°C may result in an increase in the number of
Temperature is primarily an aesthetic criterion for drinking water. Generally, cool water is more palatable than warm or cold water. In general, consumers will react to a change in water temperature. Complaints are most frequent when the temperature suddenly increases.
The turbidity and colour of filtered water may be indirectly affected by temperature, as low water temperatures tend to decrease the efficiency of water treatment processes by, for instance, affecting floc formation rates and sedimentation efficiency.
Chemical reaction rates increase with temperature, and this can lead to greater corrosion of pipes and fittings in closed systems. Scale formation in hard waters will also be greater at higher temperatures…
Water temperatures in major Australian reticulated supplies range from 10°C to 30°C. In some long, above-ground pipelines, water temperatures up to 45°C may be experienced…
The effectiveness of chlorine as a disinfectant is influenced by the temperature of the water being dosed. Generally higher temperatures result in more effective disinfection at a particular chlorine dose, but this may be counterbalanced by a more rapid loss of chlorine to the atmosphere (AWWA 1990).