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Bromide (Br-) concentrations (mg/L) in groundwater range from no observed adverse effect levels (NOAEL), which is considered safe, and increase to constituent of concern (COC) when the concentrations approach the recommended maximum levels for safety, and to potentially hazardous chemical constituent when the concentrations exceed the recommended safe levels. The default recommended NOAEL of less than or equal to 0.01 mg/L was validated with the highly sensitive chicken embryo model. Chronic and acute exposure to Br- in groundwater can induce negative consequences, which include hypothyroidism, reduced production and Br- accumulation in organs and secretion in milk, depending on the type of livestock and their physiological state, and potential interactions with environmental factors. Bromide competes with chloride (Cl-) and infiltrates the Cl- space, has a relatively long half-life in proportion to the ingestion rate, and a low renal clearance rate of approximately 5% of ingestion, leading to an accumulation in the body. The most vulnerable livestock are neonatal and suckling animals, those with a high water intake, such as during lactation, or in an adverse environment, and because of chronic exposure. The recommendation is to include Br- in chemical analysis of water quality and to assess the potential risk to livestock. [ABSTRACT FROM AUTHOR]

Bromide (Br-) concentrations (mg/L) in groundwater range from no observed adverse effect levels (NOAEL), which is considered safe, and increase to constituent of concern (COC) when the concentrations approach the recommended maximum levels for safety, and to potentially hazardous chemical constituent when the concentrations exceed the recommended safe levels. The default recommended NOAEL of less than or equal to 0.01 mg/L was validated with the highly sensitive chicken embryo model. Chronic and acute exposure to Br- in groundwater can induce negative consequences, which include hypothyroidism, reduced production and Br- accumulation in organs and secretion in milk, depending on the type of livestock and their physiological state, and potential interactions with environmental factors. Bromide competes with chloride (Cl-) and infiltrates the Cl- space, has a relatively long half-life in proportion to the ingestion rate, and a low renal clearance rate of approximately 5% of ingestion, leading to an accumulation in the body. The most vulnerable livestock are neonatal and suckling animals, those with a high water intake, such as during lactation, or in an adverse environment, and because of chronic exposure. The recommendation is to include Br- in chemical analysis of water quality and to assess the potential risk to livestock. [ABSTRACT FROM AUTHOR]

Dairy farms in central South Africa depend mostly on groundwater for domestic needs and dairy activities. Groundwater samples were collected from 37 dairy farms during 2009 and 2013. Sixteen water quality parameters were tested and compared to the standard. Four parameters in 2009 and six in 2013 exhibited 100% compliance with the standard. Nitrate, Escherichia coli and total coliforms showed relatively low compliance across farms and years. Almost all farms were noncompliant for hardness in both sampling years. T-tests revealed significant changes from 2009 to 2013 for pH (t = 2.580; p = 0.006), hardness (t = 2.197; p = 0.016) and potassium (K) (t = 1.699; p = 0.0468). For hardness, approximately 45% of the farms in 2009, and 57% in 2013, posed a health risk to sensitive consumers. More than 50% of the farms in both years demonstrated levels of nitrates that could pose a health risk, particularly for babies. High levels of coliforms and E. coli were found, indicating a health risk for clinical infections in consumers. The number of farms presenting 3 or more parameters with a health risk more than doubled from 13.5% in 2009 to 27.0% in 2013. [ABSTRACT FROM AUTHOR]

This study assessed the groundwater quality around two municipal solid waste landfill sites, in the city of Bloemfontein, Free State Province, South Africa. The two landfill sites are located in two contrasting geological terrains, with both lacking some basic facilities found in a well-designed landfill. A total of eight groundwater samples were collected from pollution monitoring boreholes near the two landfill sites, with five samples representing the northern landfill site and three samples representing the southern landfill site. The samples were collected in the autumn and winter seasons to assess any possible seasonal variations. They were analysed for physicochemical (pH, electrical conductivity (EC), total dissolve solids (TDS), chemical oxygen demand (COD) and total organic carbon (TOC)) and microbiological parameters (Escherichia coli, total coliform). The results of the analysis showed that the waters from both landfills were generally dominated by Ca, Mg, SO4, and HCO3 ions. Some of the major anions and cations in the water samples were above the South African National Standard (SANS241:2015) and World Health Organisation (WHO) permissible limits for drinking water. Majority of the boreholes had total dissolved solids and electrical conductivity values exceeding the SANS 241:2015 and WHO permissible limits. Piper trilinear plots for the two landfill sites showed that Ca(Mg)HCO3 water type predominates, but Ca(Mg)SO4 and Ca(Mg)Cl were also found. These water types were further confirmed with expanded Durov diagrams, indicating that that the boreholes represented a water type that is seldom found which is undergoing ion exchange, typical of sulphate contamination. From the SAR diagrams, boreholes in the northern landfill site had a high salinity hazard with only one borehole in the southern landfill site having a high salinity hazard. The geology was found to play a significant role in the distribution of contaminants into the groundwater systems in the study area. The study concluded that the northern landfill site had a poorer water quality in comparison to the southern landfill site based on the analysed physicochemical parameters. However, the southern landfill site showed significant microbial contamination, due to the elevated amount of E. coli and total coliform concentrations. The high permeability of the weathered dolerites in the northern landfill site might have enabled the percolation of contaminants into the groundwater resulting in the poorer water quality. [ABSTRACT FROM AUTHOR]