Water Microbiology

Waterborne pathogens are a leading cause of disease and death worldwide. Routine microbiological testing of drinking water supplies, recreational waters andenvironmental waters is essential for the protection of public health.

Microbiological water testing is based on total bacterial count, detection of indicators of faecal contamination and other specific pathogens.

The great majority of waterborne infections are the result of faecal contamination,either from humans or animals, and preventing sewage and agricultural effluent from entering water supplies is the key to safe drinking water.

Maintaining an uncontaminated water supply requires constant attention and regular monitoring by a program of testing. The most effective way to check water supplies for faecal contamination remains microbiological analysis and a range of test methods designed for that purpose has been developed for the water industry. Testing is important not just for drinking water supplies, but also for recreational and environmental waters where human contact with contaminated water could occur.

Water test proposed by Abiolabs
Total coliforms
Thermotolerant coliforms
Escherichia coli
Legionella spp
Pseudomonas aeruginosa
Staphylococcus aureus
Salmonella spp

We can test other pathogens on request

  • Total Viable Count
  • Total coliforms
  • Salmonella spp
  • Staphylococcus aureus
  • Legionella spp
Total Viable Count

This test suits for of all kinds of water as it invariably contains a variety of micro-organisms derived from various sources, such as soil and vegetation. The estimation of the overall numbers of microorganisms provide useful information for the assessment and surveillance of water quality.


The main value of colony counts lies in the detection of changes from those expected, based on frequent, long term monitoring. Any sudden increase in the count can be an early warning of serious pollution and calls for immediate investigation.

Method Process :

Applied standard: ISO 6222

Drinking Water
Spa / Pool Water
Irrigation Water
Treated Effluent

Test Report available within 5 working days after completion of tests.

To obtain reliable results, sampling shall be performed in an aseptic manner. Abiolabs offers trained samplers to meet your sampling needs.

Total coliforms

The presence and extent of faecal pollution is an important factor in assessing the quality of water and the risk to human health from infection.

The presence of coliform bacteria, may indicate a failure in the treatment, storage, or distribution system.

Examination of water samples for the presence of Escherichiacoli (E. coli), normal flora of men and other warm-blooded animal intestine, provides an indication of such pollution.

Applied standard: ISO 9308-1/2

Matrix

Drinking Water
Spa / Pool Water
Irrigation Water
Treated Effluent

Test Report available within 5 working days after completion of tests.

To obtain reliable results, sampling shall be performed in an aseptic manner. Abiolabs offers trained samplers to meet your sampling needs.

Salmonella spp

Salmonella species are bacteria which are widely distributed all over the world. They are usually classified as pathogens, although their virulence and pathogenesis vary widely. The natural hosts of Salmonella include humans, agricultural and domestic livestock, and wild animals including birds.

Humans and animals can excrete these bacteria while carrying them asymptomatically as well as during disease. It is therefore impossible to eliminate them from the environment.

The transmission of Salmonella can cause severe disease.

Salmonella can be present in all types of domestic and agricultural wastewater, freshwaters, including ground and drinking waters, as well as sea water.

Applied standard: ISO 9308-1/2

Matrix

Drinking Water
Spa / Pool Water
Irrigation Water
Treated Effluent

Test Report available within 5 working daysafter completion of tests.

To obtain reliable results, sampling shall be performed in an aseptic manner. Abiolabs offers trained samplers to meet your sampling needs.

Staphylococcus aureus

Staphylococcus aureus is relatively widespread in the environment and is a member of the normal microbial flora of the human skin. The organism is Staphylococci are occasionally detected in the gastrointestinal tract and can be detected in sewage.

Staphylococcus aureus can be released by human contact into water environments such as swimming pools, spa pools and other recreational waters. Staphylococcus aureus can occur in drinking-water supplies.

Staphylococci are slightly more resistant to chlorine residuals than E. coli, their presence in water is readily controlled by conventional treatment and disinfection processes.

Applied standard: XP-T90-412

Matrix

Drinking Water
Spa / Pool Water
Irrigation Water
Treated Effluent

Test Report available within 5 working days after completion of tests.

To obtain reliable results, sampling shall be performed in an aseptic manner. Abiolabs offers trained samplers to meet your sampling needs.

Legionella spp

Legionella is a type of bacterium found naturally in freshwater environments, like lakes and streams.

It can become a health concern when it grows and spreads in human-made water systems like

Hot water tanks and heaters
Large plumbing system
Cooling towers ( air-conditioning units for large buildings)
Decorative fountains
This bacterium grows best in warm water.

Applied standard: XP-T90-412

Matrix

Drinking Water
Spa / Pool Water
Irrigation Water
Treated Effluent

Test Report available within 5 working days after completion of tests.

To obtain reliable results, sampling shall be performed in an aseptic manner. Abiolabs offers trained samplers to meet your sampling needs.

Frequently asked Questions – FAQ
What should I test for in my drinking (potable) water?

“I want to test my drinking water” is a frequent request.

Our first question is ”What do you want testing for?”

Unfortunately this is as far as most people have got, so hopefully over the next couple of minutes of reading we can help you make an informed decision on what, if anything, you should test your potable/drinking water for. 

Are you concerned about bacteria in your drinking water?

This is a common concern and is often something people with boreholes, wells or natural springs are wondering, especially if they live near farmland and are concerned about contamination with faecal matter. The most effective way to test for this is E. Coli & Coliform water analysis. These bacteria are used as an identifier of when the water may be contaminated by more dangerous organisms like Salmonella. This analysis also includes Aerobic Colony Count also known as TVC (Total Viable Count) which can give an indication of the general quality of the water.

Feed water can also test for Legionella and Pseudomonas aeruginosa both of which are more associated with colonisation of the property’s plumbing fixtures and fittings.

Where and when should you test?

Cares home – every six months
Health care premises – every six months
Larger buildings – every six months
Bore holes / wells / Private Springs – every six months but more frequently for larger systems
Any persons who needs reassurrance of quality of their drinking water

Please note this analysis needs to arrive at the lab the day after sampling.

Sampling for microbiology?

Obtaining representative microbiological samples can take considerable care and timing.Microbiological samples can often require large sample volumes and are easily contaminated, as bacteria are present on most surfaces and in the air. They also have short holding times (preferably less than six hours).

Communication with the laboratory is necessary to ensure that samples can be received and processed efficiently.

Specific precautions need to betaken to minimise the possibility of sample contamination. Prior to and between collection of samples, hands should be washed then disinfected with an alcohol based hand disinfectant, eg 70% ethanol or hexifoam. Wearing latex gloves will help avoid contamination of samples during collection. Gloves should be changed between samples.

Whenever possible collect the sample directly into the sample container, ensuring that the inside of the cap and the neck of the container are not touched or exposed to the air for longer than necessary.

Abiolabs is be able to supply suitably treated bottles.

The hierarchy with regard to sampling equipment for microbiological analytes is:

Minimise usage of sampling equipment where possible, thus avoiding risk of contamination.

Use disposable pre-sterilised equipment for each sample.

All sections of the sampling equipment that may come in contact with the container and the water body should be flamed. The burner should be fuelled by propane or butane. Methylated spirit burners do not produce a flame hot enough for sterilisation.

Forplastic and glass or when unsafe to use a flame, a solution of 10% sodiumhypochlorite should be used. (Household bleach can range from 2% to 15% sodiumhypochlorite, and will degrade over time). Flood the surface with the solutionand wait approximately two minutes. For pump lines and hoses, trap bleachsolution within the hose or equipment. Wait for a minimum of 15 minutes.

In an emergency, scalding with boiling water for 10 minutes may disinfect a suitable glass or plastic container and equipment.

What is an indicator organism?

What is an Indicator organism?

Indicator organisms are bacterial species that are present in high numbers in human and animal faeces and are also present in sewage effluent. Ideally they should not originate from other sources, should not be able to multiply in water supplies or aquatic environments and should be relatively simple to isolate from water samples. Unfortunately, no one organism completely meets all these requirements, but it is Escherichia coli that most closely matches the criteria for an ideal indicator species.

When do we need to test for water borne pathogens?

When do we need to test for water borne pathogens?

There are some situations where it is necessary to test directly for water borne pathogens: when an outbreak is suspected or for a routine check on specific microorganisms. For example, water supplies are routinely monitored for the presence of:

Legionella spp (where aerosols may be generated, such as contained in cooling towersand humidifiers),

Pseudomonas aeruginosa (especially in treated recreational waters, such as swimming pools).

Salmonella spp

Escherichia coli

Other microbial quality parameters

In addition to tests for indicator organisms and certain specific pathogens,non-selective colony counts are also routinely carried out to determine the population of heterotrophic bacteria present. Counts at two temperatures (22oCand 37oC) are typically performed to provide information on the general microbiological population of the water and detect sudden changes in water quality.