South Mackay (Queensland) – Lead
2015/2016: South Mackay (Lead) 0.00525mg/L (max), <0.001mg/L (min)
Lead Guideline reduced from 0.01mg/L to 0.005mg/L in June 2025. “The concentration of lead in water within premises may be higher, especially in older buildings, due to contact of the water with lead-containing plumbing products (enHealth 2021). A review found several Australian and international studies that detected up to 0.162 mg/L of lead in drinking water due to leaching from lead-containing plumbing materials including taps and lead service lines, suggesting that leaching of lead from lead-containing plumbing materials can be substantial (SLR 2023)… Based on health considerations, the concentration of lead in drinking water should not exceed 0.005 mg/L.”
South Mackay (Queensland) – Selenium
2013/2014: South Mackay Selenium 0.0033mg/L (max)
Based on health considerations, the concentration of selenium in drinking water should not exceed 0.004 mg/L (2011-2025 guideline 0.01mg/L). “General description Selenium (Se) and selenium salts are widespread in the environment. Selenium is released from natural and human-made sources (such as the burning of coal). Selenium is also a by-product of the processing of sulfide ores, chiefly in the copper refining industry. The major use of selenium is in the manufacture of electronic components. It is used in several other industries, and selenium compounds are used in some insecticides, in hair shampoos as an antidandruff agent, and as a nutritional feed additive for poultry and livestock. Selenium copper alloys have also been identified as a potential replacement for lead copper alloys in plumbing products. Further information on lead replacements in plumbing products (such as selenium copper alloys) is available in Information Sheet 4.1 – Metal and metalloid chemicals leaching from plumbing products. Selenium concentrations in drinking water source waters are generally very low and depend on local geochemistry, climatic conditions (e.g. drought), pH and the presence of iron salts. Selenium in water is mainly present as inorganic compounds, predominantly selenate. Weathering of rocks and soil may result in low levels of selenium in water, which may be taken up by plants (SLR 2022). Food is the major source of intake for Australians. Cereal and grain products contribute most to intake, while fish and liver contain the highest selenium concentrations.” ADWG 2025