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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]

Recent advances in analytical techniques have allowed hydro-geochemical databases to form an essential component of animal and human epidemiological studies. Geographically localised communities and livestock production systems have a higher incidence of risk factors, and therefore baseline concentrations of key health elements are required to assess the quality of the water. Risk assessments conducted for drinking water for indigenous goats in rural communal livestock production systems for three separate communities found several trace elements (As, Br, Cd, F, Pb, Hg, Mo and Se) occurring as localised anomalies in the aquatic environment at concentrations exceeding local and international guidelines (at times by several orders of magnitude). The watering points assessed are capable of contributing significantly to the mineral requirements of the indigenous goats thus exposed. Potential hazards were identified that impact on the norms of health, palatability and product quality for human consumption. Hydro-geochemical correlations were noted that increase both the risk associated with exposure and the likelihood of incomplete diagnosis of mineral related disorders. Recommendations are also made with regard to a programme monitoring water quality and the need to include water chemistry when formulating rations, mineral supplements and diagnosing disorders or diseases across different production environments. [ABSTRACT FROM AUTHOR]