Testing of products for use in contact with drinking water
We play a key role in protecting public health by providing leading product manufacturers in Australia and around the world with NATA-accredited laboratory testing services to AS/NZS 4020:2018 standard.
The Standard is designed to test any product that comes in contact with drinking water. We also provides testing to equivalent International Standards (eg BS6920)
As the first laboratory in Australia to offer testing to AS/NZS 4020 standards, we have tested thousand of products since 1992.
Certificates of testing and test reports issued by our laboratory are recognised by Standards Australia and the major Water Authorities.
The Standard requires that products do not affect the taste or appearance of water; do not support the growth of microorganisms; and do not release cytotoxic or mutagenic compounds or metals. The tests required are specific to the type of product submitted.
Appendix C - Taste of Water Extract
A trained panel tastes water extracts to determine whether products release any compounds that impart discernible taste.
Water that has been in contact with a product is examined for any increase in colour or turbidity.
Appendix E - Growth of Aquatic Microorganisms
In a test that takes 8 weeks, products are examined for the ability to support bacterial growth by monitoring dissolved oxygen levels.
Appendix F - Cytotoxic Activity of Water Extract
Water extracts are tested for cytotoxicity using mammalian cell lines maintained in a laboratory culture. Any adverse effect on the health of the cells is recorded as a cytotoxic effect.
Appendix G - Mutagenic Activity of Water Extract
An AMES test is used to determine whether products release mutagenic compounds. Water extracts are mixed with specific bacteria. Any measured change in genetic nature of the bacteria is regarded as evidence of mutagenic activity.
Appendix H - Extraction of Metals
Water extracts are examined for the release of Arsenic, Antimony Barium, Cadmium, Chromium, Copper, Lead, Mercury, Molybdenum, Nickel, Selenium and Silver. The limits are in line with NHMRC guidelines. The extraction procedure is either by end-of-line test or in-line test.
Appendix J - High Temperature Tests
Products in contact with hot water are tested at higher temperatures. This applies to hot water systems, boiling water dispensers (including their outlet taps, fittings and tubes).
Clause 6.8 – Organic Compounds
Water extracts are analysed for organic compounds using USEPA methods. The limits are in line with ADWG.
The Australian Water Quality Centre has tested a wide range of products including:
- Elastomeric Compounds (EPDM, NBR, Silicone)
- Hot Water Systems
- Gas Instantaneous
- Solar Hot Water Panel
- Heat Pump/Heat Exchanger Systems
- Electric Storage
- Mineral Based Lubricant
- Synthetic Lubricant
- High Temperature Formulas
- Epoxy Coating/Paints
- Acrylic Paints
- Powder Coatings
- Ceramic Paints
- Fusion Bonded Epoxy
- Tape Ware Tubing
- Drinking Water Dispensing Tubing
- Carbonated Water Dispensing System
- Hose assembly fitting for storage, conveyance, and aviation industry
- Tank Lining
- Films and Potable Liner Compounds
- Specific adhesives and bonding agents for liners
- Wholly Metallic
- Plastic Piping
- Cement Lined
- Fibreglass Compound
- Pipe Solder, Fittings and Adhesives
- Multilayer Pipe
- Silicone Base
- Rubber Composites Based
- Fusion Bonded Seal Composites
- Flow Control Valves (In-Live and End-of-Line)
- Backflow Prevention Valves
- Pressure/Temperature Relief Valves
- Flow Sensors and Metered Valves
- Horizontal/Vertical Pumps
- Circulator Pumps
- Hot/Cold Beverage Dispenser Pumps
- Submersible/Bore Pumps
- Water Filter Components – Solid Media (non-granular media included)
- Flow Control
- UV Units
- Tap Ware
- Kitchen/Basin Tap Ware
- Bathroom/shower Units/Diverters
- Electric Sensor Tap Ware
- Industrial Tap Ware
- Cement Based Products
- Tank Structure
- Crack/Seal Repair
- Rainwater Harvesting
- Roofing and Guttering Material
- Leaf Strainer/Filter
- Paint, Sealants and Repair Kits
- Hospitality/Beverage Dispensing Units
- Coffee machines
- Ice machines
- Chilled/Ice Machine
- Post and Premix Soft Drink Dispensing Systems
The Ames test is used to determine mutagenic activity in water extracts are component of AS/NZS 4020. Water extracts are mixed with specific bacteria and any measured change in genetic nature of the bacteria is regarded as evidence of mutagenic activity. The Ames is a reverse mutation assay.
The Ames test was developed to determine whether a chemical is a mutagen. The test assumes that if a substance is mutagenic it may also be carcinogenic. A number of mutagenic compounds first detected by the Ames test have shown to be carcinogenic in animal tests, including some hair dyes and several protein pyrolysis products produced when cooking foods.
The test is also used to determine whether mutagenic compounds are present in potable water as a result of water treatment processes. Water extracts are mixed with a test strain of Salmonella typhimurium that carries a defective (mutant) gene making it unable to synthesise the amino acid histidine from the ingredients in the culture medium. However, some types of mutations can be reversed, a back mutation, with the gene regaining its function. These revertants are able to grow on a medium lacking histidine.
Histidine requiring strains are used for the Ames test. Each tester strain contains a different type of mutation in the histidine operon (eg frameshift mutagens and base-pair substitutions). The standard tester strains contain other mutations that greatly increase their ability to detect mutagens. The tester strains are relatively non-virulent because they lack the galactose operon which is essential for making the lipopolysaccharide coating required for virulence.
Salmonella typhimurium is a prokaryote is and consequently not the ideal model of the human body, hence liver enzymes are added to the test. Liver enzymes are used as some chemicals are not mutagenic in themselves but are converted into mutagens when they are metabolised in the body.
Tester strains are grown in a specialised nutrient broth as some nutrient broths that contain proteins extracted from beef at high temperature are possibly mutagenic.
The cells are combined with water extract samples, positive controls and controls with and without liver enzymes.
Spontaneous reversion of the tester strains to histidine independence is measured in each Ames test and is expressed as the number of spontaneous revertants per plate. Spontaneous reversion for each strain is at a frequency that is characteristic of the strain.
A positive mutagenic response is measured when the mean number of revertants between the control and test extract exceeds the sum of two standard deviations. A mutgenic reponse does not necessarily mean the test material is harmful to humans, but indicates that there are substances that require further investigation.
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