15/4/21: Nettle Hill (South Australia) E.coli 1cfu/100mL
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
Nettle Hill (South Australia) – Trihalomethanes
Breaches to Australian Drinking Water Guidelines Levels Only
12/01/2012 Nettle Hill Nettle Hill Rd Trihalomethanes – Total 272 ug/L
5/04/2012 Nettle Hill Nettle Hill Rd Trihalomethanes – Total 267 ug/L
19/04/2012 Nettle Hill CT Nettle Hill Rd Trihalomethanes – Total 257 ug/L
3/05/2012 Nettle Hill CT Nettle Hill Rd Trihalomethanes – Total 260 ug/L
27/02/2014 Nettle Hill CT Nettle Hill Rd Trihalomethanes – Total 252 ug/L
24/04/2014 Nettle Hill CT Nettle Hill Rd Trihalomethanes – Total 260 ug/L
5/06/2014 Nettle Hill CT Nettle Hill Rd Trihalomethanes – Total 253 ug/L
31/12/2015 Nettle Hill CT Nettle Hill Rd Trihalomethanes – Total 275 ug/L
2/06/2016 Nettle Hill CT Nettle Hill Rd Trihalomethanes – Total 259 ug/L
9/05/2019 Nettle Hill Trihalomethanes 256 ug/l
2018/19: Nettle Hill (South Australia) Trihalomethanes 256ug/L (max), 223.3ug/L (av.)
6/5/21: Nettle Hill (South Australia) Trihalomethanes 244ug/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/contaminants/in
Nettle Hill (South Australia) – Bromodichloromethane
2018/19: Nettle Hill (South Australia) Bromodichloromethane 89ug/L (max), 76.4ug/L (av.)
5/3/20: Nettle Hill (South Australia) Bromodichloromethane 82ug/L. (2019/20 av. 70ug/L)
2/7/20: Nettle Hill (South Australia) Bromodichloromethane 68ug/L
30/7/20: Nettle Hill (South Australia) Bromodichloromethane 66ug/L
3/9/20: Nettle Hill (South Australia) Bromodichloromethane 67ug/L
1/10/20: Nettle Hill (South Australia) Bromodichloromethane 73ug/L
5/11/20: Nettle Hill (South Australia) Bromodichloromethane 68ug/L
3/12/20: Nettle Hill (South Australia) Bromodichloromethane 75ug/L
7/1/21: Nettle Hill (South Australia) Bromodichloromethane 79ug/L
4/2/21: Nettle Hill (South Australia) Bromodichloromethane 76ug/L
4/3/21: Nettle Hill (South Australia) Bromodichloromethane 77ug/L
1/4/21: Nettle Hill (South Australia) Bromodichloromethane 79ug/L
6/5/21: Nettle Hill (South Australia) Bromodichloromethane 88ug/L
6/5/21: Nettle Hill (South Australia) Bromodichloromethane 82ug/L
30/9/21: Nettle Hill (South Australia) Bromodichloromethane 86ug/L (max), 56.3ug/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)