Sellicks Beach – Hastings Avenue (South Australia) – Trihalomethanes
6/5/20: Sellicks Beach (Hastings Avenue) Trihalomethanes 253ug/L (max) 218.92ug/L (av. 2019/20)
8/9/21: Sellicks Beach Hastings Av Trihalomethanes 243ug/L (max) 155.7ug/L (av. 2021/22)
Trihalomethanes Australian Guideline Level 250μg/L (0.25mg/L)
Why and how are THMs formed?
“When chlorine is added to water with organic material, such as algae, river weeds, and decaying leaves, THMs are formed. Residual chlorine molecules react with this harmless organic material to form a group of chlorinated chemical compounds, THMs. They are tasteless and odourless, but harmful and potentially toxic. The quantity of by-products formed is determined by several factors, such as the amount and type of organic material present in water, temperature, pH, chlorine dosage, contact time available for chlorine, and bromide concentration in the water. The organic matter in water mainly consists of a) humic substance, which is the organic portion of soil that remains after prolonged microbial decomposition formed by the decay of leaves, wood, and other vegetable matter; and b) fulvic acid, which is a water soluble substance of low molecular weight that is derived from humus”. Source: https://water.epa.gov/drink/contaminants/in
Sellicks Beach [Hastings Avenue] (South Australia) – Bromodichloromethane
2018/19: Sellicks Beach [Hastings Avenue] (South Australia) Bromodichloromethane 83ug/L (max), 73.6ug/L (av.)
6/5/20: Sellicks Beach (Hastings Avenue) (South Australia) Bromodichloromethane 89ug/L (2019/20 av: 76.9ug/L)
29/7/20: Sellicks Beach (Hastings Avenue) (South Australia) Bromodichloromethane 72ug/L
2/9/20: Sellicks Beach (Hastings Avenue) (South Australia) Bromodichloromethane 78ug/L
30/9/20: Sellicks Beach (Hastings Avenue) (South Australia) Bromodichloromethane 79ug/L
4/11/20: Sellicks Beach (Hastings Avenue) (South Australia) Bromodichloromethane 64ug/L
2/12/20: Sellicks Beach (Hastings Avenue) (South Australia) Bromodichloromethane 76ug/L
6/1/21: Sellicks Beach (Hastings Avenue) (South Australia) Bromodichloromethane 78ug/L
3/2/21: Sellicks Beach (Hastings Avenue) (South Australia) Bromodichloromethane 85ug/L
3/3/21: Sellicks Beach (Hastings Avenue) (South Australia) Bromodichloromethane 83ug/L
31/3/21: Sellicks Beach (Hastings Avenue) (South Australia) Bromodichloromethane 78ug/L
5/5/21: Sellicks Beach (Hastings Avenue) (South Australia) Bromodichloromethane 78ug/L
2/6/21: Sellicks Beach (Hastings Avenue) (South Australia) Bromodichloromethane 82ug/L
8/9/21: Sellicks Beach (Hastings Ave.) Bromodichloromethane 83ug/L (max), (51.75ug/L av. 2021/22)
WHO Guideline level BDCM: 60ug/L (Australian Guideline for BDCM is included in the combined total of BDCM, Chloroform, Dibromochloromethane and Bromoform. THM guideline is 250ug/L)
“Carcinogenicity : Bromodichloromethane is reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in experimental animals.
Cancer Studies in Experimental Animals: Oral exposure to bromodichloromethane caused tumors at several different tissue sites in mice and rats. Administration of bromodichloromethane by stomach tube caused benign and malignant kidney tumors (tubular-cell adenoma and adenocarcinoma) in male mice and in rats of both sexes, benign and
malignant liver tumors (hepatocellular adenoma and carcinoma) in female mice, and benign and malignant colon tumors (adenomatous polyps and adenocarcinoma) in rats of both sexes (NTP 1987, ATSDR 1989, IARC 1991, 1999).
Since bromodichloromethane was listed in the Sixth Annual Report on Carcinogens, additional studies in rats have been identified. Administration of bromodichloromethane in the drinking water increased the combined incidence of benign and malignant liver tumors (hepatocellular adenoma or carcinoma) in males (George et al. 2002) and caused benign liver tumors (hepatocellular adenoma) in females (Tumasonis et al. 1987).
Cancer Studies in Humans
The data available from epidemiological studies are inadequate to evaluate the relationship between human cancer and exposure specifically to bromodichloromethane. Several epidemiological studies indicated a possible association between ingestion of chlorinated drinking water (which typically contains bromodichloromethane) and increased risk of
cancer in humans, but these studies could not provide information on whether any observed effects were due to bromodichloromethane or to one or more of the hundreds of other disinfection by-products also present in chlorinated water (ATSDR 1989).” (1)
Sellicks Beach (South Australia) – Total Haloacetic Acids
1/7/20: Sellicks Beach (Hastings Avenue) Total Haloacetic Acid (HAA9) 125ug/L
6/1/21: Sellicks Beach (Hastings Avenue) Total Haloacetic Acid (HAA9) 178ug/L
8/9/21: Sellicks Beach (Hastings Avenue) Total Haloacetic Acid (HAA 9) 228ug/L (max) 151.5ug/L (av. 2021/22)
“Chloroacetic acids are produced in drinking water as by-products of the reaction between chlorine and naturally occurring humic and fulvic acids. Concentrations reported overseas range up to 0.16mg/L and are typically about half the chloroform concentration. The chloroacetic acids are used commercially as reagents or intermediates in the preparation of a wide variety of chemicals. Monochloroacetic acid can be used as a pre-emergent herbicide, dichloroacetic acid as an ingredient in some pharmaceutical products, and trichloroacetic acid as a herbicide, soil sterilant and antiseptic.” Australian Drinking Water Guidelines – National Health and Medical Research Council
8/6/22 Sellicks Beach (South Australia) 8/6/22 Mercury 0.00168mg/L (max) 0.0002mg/L (av. 2021/22)
Mercury: Australian Drinking Water Guideline 0.001mg/L
Mercury, if it enters the ecosystem can transform into the more toxic methylmercury where it can bioaccumulate. Methylmercury is highly toxic to human embryos, fetuses, infants and children. Mercury has numerous sources including old gold mines, where mercury was used in gold recovery process. It has been estimated that 950 tonnes of
mercury was deposited into Victorian soil, rivers and streams during the various gold rushes.
https://ntn.org.au/wp-content/uploads/2010/05/mercury_brief20101.pdf
2022/23: Sellicks Beach (South Australia) – pH (alkaline)
2022/23: Sellicks Beach Hastings Beach. (South Australia) pH 8.6 (av.)
Based on the need to reduce corrosion and encrustation in pipes and fittings, the pH of
drinking water should be between 6.5 and 8.5.
New concrete tanks and cement-mortar lined pipes can significantly increase pH and
a value up to 9.2 may be tolerated, provided monitoring indicates no deterioration in
microbiological quality.
pH is a measure of the hydrogen ion concentration of water. It is measured on a logarithmic scale from 0 to 14. A pH of 7 is neutral, greater than 7 is alkaline, and less than 7 is acidic.
One of the major objectives in controlling pH is to minimise corrosion and encrustation in pipes and fittings. Corrosion can be reduced by the formation of a protective layer of calcium carbonate on the inside of the pipe or fitting, and the formation of this layer is affected by pH, temperature, the availability of calcium (hardness) and carbon dioxide. If the water is too alkaline (above pH 8.5), the rapid deposition and build-up of calcium carbonate that can result may eventually block the pipe.