2018/23 – Elizabeth Grove (South Australia) – Trihalomethanes, Bromodichloromethane, Total Haloacetic Acid

Elizabeth Grove (South Australia) – Trihalomethanes

Breaches to Australian Drinking Water Guidelines Levels Only

10-May-18 Elizabeth Grove Trihalomethanes – Total 258 µg/L

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/contaminant

Elizabeth Grove (South Australia) – Bromodichloromethane

2018/19: Elizabeth Grove (South Australia) Bromodichloromethane 69ug/L (max), 39.6ug/L (av.)

2022/23: Elizabeth Grove (South Australia) Bromodichloromethane 81ug/L (max), 57.5ug/L (av.)

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)

Elizabeth Grove (South Australia) – HAA’s

2/7/19: Elizabeth Grove Total Haloacetic Acid 0.104mg/L

9/6/23: Elizabeth Grove Total Haloacetic Acid 0.128mg/L, (0.115mg/L av. 2022/23)

Australian Guidelines Trichloroacetic Acid 0.100mg/L, Dichloroacetic Acid 0.100mg/L

“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…

Elizabeth Grove (South Australia) – Chloroketones

29/6/23: Elizabeth Grove (South Australia): 1 1-dichloropropan-2-one 1.2ug/L

Data are inadequate to set guideline values for chloroketones in drinking water.
The chloroketones are produced in drinking water as by-products of the reaction between naturally occurring organic matter and chlorine. No data are available on other sources or uses for these compounds. Concentrations of chloroketones in drinking water reported overseas are very low and are estimated at less than 0.01 mg/L.

In major Australian reticulated supplies 1,1,1-trichloropropanone has been recorded in concentrations up to 0.02 mg/L, but it is usually below the limit of determination of 0.0005 mg/L. No data are available for other chloroketones.

The presence of chloroketones in drinking water can be minimised by removing naturally occurring organic matter from the source water, by reducing the amount of chlorine added, or by the use of alternative disinfectants.” 2011 ADWG