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  • How do I read my SANS241 Drinking Water Analysis?
    Reading your Drinking Water Analysis Report may seem like a daunting task but we are always here to help. The new SANS241:2015 Drinking Water Standards were published in March 2015. The new SANS241:2015 Standards can be purchased here SABS webstore
  • Water Quality
    The water we use for drinking, washing, and preparing food, comes from rainwater, surface water (rivers, dams etc.) and groundwater sources (springs and borehole water). The amount of fresh water available is limited. Water quality describes water’s suitability for use, concerning its chemical, physical and microbial properties, for drinking, irrigation, bathing, and effluent. Safe water should contain no chemical or radioactive substances, be free from disease-causing organisms and be non-corrosion and scaling forming. Water quality is measured by; the concentration of dissolved oxygen bacterium levels salinity (amount of salt) turbidity (amount of material suspended) the concentration of microscopic algae presence of pesticides, herbicides, heavy metals and other contaminants Various analyses determine water quality and the suitability for the intended purpose, i.e. drinking, swimming, effluent, irrigation, bathing etc. Poor water quality can pose health risks to all organisms, including flora and fauna. Note: the suitability of water for gardening purposes depends on a number of other factors, such as climate and soil quality. Properties of Water Quality Chemical Water Quality: refers to the concentration of dissolved substances such as salts, metals and organic chemicals. Many chemical substances are essential for daily intake, but high concentrations make water unpleasant and cause illness. Physical Water Quality: refers to water properties determined by physical methods such as conductivity, pH and turbidity. These qualities mainly affect the taste, odour and appearance (aseptic) of the water. Microbiological Water Quality: refers to the presence of organisms that cannot be seen by the naked eye, such as viruses, protozoa and bacteria (pathogens). Many of these are associated with water-borne diseases. Microbial indicators indicate a potential risk for faecal pollution and infectious diseases, as it is costly and difficult to detect pathogens in water. Microbial indicators include Total Coliforms, E.coli, Faecal Coliforms and Heterotrophic Plate Counts. Why is it important to test your water quality? Water is the link between various communities and resources. What happens in catchment areas is reflected in the water quality throughout the entire system. The results of human activities in industry, construction, lifestyle and agriculture ultimately end up in the nearby rivers through run-off. If pollution occurs upstream, it runs downstream and eventually into our oceans. Water quality is dependent on the interaction within the river and its surrounding catchment area. The processes within the catchment area can either maintain a healthy ecosystem or disrupt it and degrade the water supply. Affecting water quality downstream and potentially, if severe enough, groundwater systems and our oceans as well.
  • Indicators of Water Quality
    Group A: includes general indicators that should be tested frequently as they are indicators of potential problems Electrical Conductivity (EC): an indicator of Total Dissolved Salts (TDS), also establishes if the water is drinkable and capable of quenching thirst. Faecal coliforms: indicating the possible presence of disease-causing organisms. Total Coliforms, E.coli and HPC: indicate the general hygiene of the water pH: has a marked effect on taste and indicates possible corrosive properties. Turbidity: affects the appearance, affecting the aesthetic acceptability of water. Free Chlorine (residual): is the measure of the effectiveness of the disinfection of water. Residual chlorine is the concentration of chlorine remaining at least 30 minutes after disinfection. (Only found in treated/Municipal water) Group B: substances commonly present at concentrations that may lead to health problems and should be determined before being supplied. Arsenic (As): predominantly present in mining areas Nitrate + Nitrite: predominant in groundwater samples, particularly in agricultural areas Fluoride (F): predominant in hot arid areas Sulphate (SO4): predominantly common in mining areas Chloride (Cl): predominant in hot arid areas Total Coliforms: provides indication of disease-causing organisms, indicator of disinfection effectiveness. Group C: substances that occur less frequently at concentrations of health concern and should be treated in areas where soft water of low pH is used. Cadmium (Cd): occurs along with zinc in acidic waters, where it may have been dissolved from appliances Copper (Cu): effects the colour of the water, normally occurs when copper piping is used to carry water with a low pH Group D: substances may commonly be present at concentrations of aesthetic and economic concern in domestic water sources Calcium (Ca): can cause scaling and reduces the lathering of soap Sodium (Na): effects the taste of water, resulting in a bitter taste at higher concentrations Iron (Fe): affects the taste of water, and can also cause a discolouration (reddish brown)/ Manganese (Mn): common cause of the black or brown discolouration of fixtures and stains in laundry. Predominantly found in mining areas Magnesium (Mg): effects the taste of water, it is bitter at high concentrations. Adds to the effects of calcium Potassium (K): effects the taste of water, resulting in a bitter taste at higher concentrations Zinc (Zn): effects the taste of water. Caused by acidic water dissolving the zinc from galvanised pipes or appliances. Total Hardness: the combination of Ca and Mg
  • What is Polluted Water?
    Water that is not safe for consumption or irrigation is polluted. Water pollution occurs when water is not fit for use as a result of human activities. These include intensive irrigation, mining activities, industries and dense human settlements. In South Africa, clean water is a scarce commodity. Our water quality is decreasing due to increased pollution, destruction of river catchments, urbanisation, deforestation, damning, destruction of wetlands, industry, mining, agriculture, energy use and accidental water pollution. As our population increases, there is an increase in pollution and catchment destruction. Who uses water? domestic users: drinking, food preparation, washing, bathing and gardening recreational users: swimming and fishing industrial users: power generation, process water agricultural users: watering crops and livestock farming
  • Faecal Coliforms and Total Coliforms
    Faecal coliforms (FC) and total coliforms (TCC) are the most commonly used indicator of faecal contamination in water. These bacteria inhabit the digestive system of all warm-blooded animals, including humans. Natural surface waters with good microbial quality have few disease-causing microbes. Many disease-causing microbes result from human faeces contaminating the water. It is impossible to test water for all the disease-causing microbes, instead microbial indicators are tested for. They tell us: water might be polluted with human or warm-blooded animal faeces if faeces are present in the water, then disease-causing microbes might be present as well When faecal coliforms are present in water, they indicate the possible presence of disease-causing organisms that may cause gastrointestinal diseases. Faecal coliform presence is an indication of faecal pollution. However, not all faecal coliforms originate from humans or other mammals. Therefore, E.coli is a specific indicator for faecal contamination and pathogenic microbial presence. Diseases like: typhoid, hepatitis, cholera, gastroenteritis dysentery and, ear and skin infections can be contracted from water. Treatment: Water treatment includes flocculation, coagulation and filtration to reduce the bacterial count. Complete removal requires disinfection by chemical (chlorine) or physical methods (boiling or UV Filtration). NOTE: disinfection is achieved more easily in clear water as bacteria (and pathogens) may survive by suspended matter
  • Free Chlorine (Free Cl2)
    Free Chlorine (Residual) is the chlorine concentration remaining at least 30 minutes after disinfection of water with chlorine. Chlorine is a chemical used to disinfect water before being discharged into the distribution system. Chlorine reacts with iron, manganese, hydrogen sulphide and microbial matter possibly present in the water. The free available chlorine indicates the efficacy of the disinfection process and probable microbiological safety. The residual chlorine also protects against secondary contamination in the distribution system. Low levels of free chlorine allow bacteria and selected viruses to multiply, resulting in water-borne disease. The absence of free chlorine in water indicates that treatment did not occur or insufficient chlorine dosing occurred. Excessively high concentrations of free chlorine can irritate mucous membranes, nausea and vomiting. High concentrations of chlorine react with organic material in drinking water forming, Trihalomethanes (THMs). THMs have been shown as potentially carcinogenic and are therefore carefully monitored in water routinely chlorinated. Treatment: Activated carbon filters remove excessive chlorine.
  • Electrical Conductivity (EC)
    Electrical Conductivity (EC) is the measure of the ease with which water conducts electricity. It is the electrical measure of the concentration of solids dissolved in a solution i.e., chemical salts and minerals; calcium bicarbonate, nitrogen, phosphates, sulphates, chlorides, iron and other metals. Distilled water is a low conductor, while seawater is highly conductive due to its high salt content. The EC reading indicates: what the Total Dissolved Salts (TDS) content is the salinity of the water origin of the water. If the water travelled over granite, the EC should be around 5 mS/m. If the water travelled over sedimentary rock, the EC is higher, from 30 to 150 mS/m. possible location nearby the sea changes in climate conditions. During droughts, water is high in EC due to higher concentrations of minerals. possible pollution resulting from nearby fertilizer run-off possible pollution due to untreated effluent Health effects occur only at levels above 370mS/m: - Disturbance of salt and water balance in infants, causing adverse effects - Individuals with high blood pressure or heart conditions are at risk - Adversely affect individuals with renal disease - Laxative effects, where there are elevated concentrations of Sulphate additionally present. Aesthetic effects result in a “salty” taste to the water from reading above 150mS/m and, readings above 300mS/m will not quench thirst. Water in rivers and dams usually contain low concentrations of ions. EC increases due to pollution, conductivity increases. The water will begin tasting salty and become unsafe to drink. Water with high EC can kill plants, corrode pipes and even block pipes. Treatment: Energy-intensive processes such as; reverse-osmosis or electrodialysis, distillation or demineralisation with a mixed bed ion-exchange process.
  • Turbidity (NTU)
    Turbidity (NTU) is the light-scattering ability of water, the measure of its cloudiness or muddiness. Clear water has low turbidity. Suspended matter in water causes high turbidity. This matter usually consists of debris and living organisms. Most river and dam water are full of small grains, soil and algae. Soil erosion, exaction, industrial waste, sewage leaks and microbes are causes of turbidity. Turbidity does not have direct health effects per se, but is one indicator of microbial water quality and inefficient water treatment. Suspended debris provides a large surface for colonisation by bacteria and other microorganisms, making it unsafe to drink. The presence of debris may also affect the taste and colour of the water. Highly turbid water may reduce the ability of plants to grow and photosynthesis without sunlight. Meaning plants in surface waters will stop growing. Grains in turbid water may also block the gills of aquatic animals. Hunting animals will have difficulty finding prey, leading to underdevelopment. Finally, leading to a loss of plant and animal diversity. Treatment: Removal of turbidity includes flocculation, settlement and filtration. Excessive turbidity in water can cause treatment problems with purification, flocculation and filtration. High turbidity additionally affects disinfection processes.
  • Arsenic (As)
    Arsenic is a poisonous semi-metal, sometimes used in rat poison. In small concentrations, Arsenic is essential to immune system function and hair and skin integrity. This semi-metal has no taste, smell or colour in water and is detected by ICP. High concentrations of As are resultant from pollution from mining and agricultural activities. Health effects include: Bathing and ingesting water with high concentrations can result in Arsenic Poisoning. As can be absorbed through the skin, thus even bathing in water with high concentrations can result in acute poisoning. As poisoning presents as skin lesions, more acute poising cases can result in a sensory loss in the peripheral nerves and gastrointestinal system. 0.01 – 0.05 mg/L – insignificant health effects on sensitive groups 0.05 – 0.2 mg/L – increasing effects on sensitive groups 0.2 – 2.0 mg/L – risk of chronic health effects > 2.0 mg/L – risk of acute health effects Treatment: Prevalent-form Arsenic is readily removed from water by flocculation with ferric salts. Pre-oxidation with an oxidant is required if As is in trivalent form. As removal requires continual monitoring and analysis to ensure break-through does not occur. Home-treatment ion-exchange kits are available to treat small volumes of water.
  • Cadmium (Cd)
    Cadmium is a highly poisonous soft metal, found in galvanising and is used to protect metals against corrosion. This metal is odourless, tasteless in water. Health effects include: Acute health effects are experienced from Cadmium (Cd) poisoning. Symptoms include food poisoning-like symptoms (i.e. nausea, vomiting and diarrhoea), which is clinically indistinguishable from microbiological food poisoning. Chronic health effects include kidney damage and pain in the bones (“ouch-ouch” or “Itai-itai” disease). Treatment: Cadmium is removed from water by flocculation with ferric salt. Full removal may be effected by raising the pH with lime, followed by settlement, filtration, and pH adjustment. Effective removal requires trained treatments, continual monitoring, and analysis. Home-treatment Ion-exchange kits are available to treat small volumes of water your answer here
  • Boron (B)
    Boron is the 51st most common element found. It is primarily combined with oxygen compounds, called Borates. Borate-containing minerals are mined and processed to produce borates for manufacturing. • glass and ceramics products • soaps, bleaches, and detergents • fire retardants • pesticides Health effects include: Exposure to large amounts of boron (about 30 g of boric acid) over short periods can affect the stomach, intestines, liver, kidney, and brain and can eventually lead to death. Treatment: Boron specific ion-exchange resin, strong base anion-exchange resin and reverse osmosis systems treat high levels of boron in water. Reverse osmosis systems have limited ability.
  • Calcium (Ca)
    Calcium is an alkaline earth metal that reacts with water to form calcium hydroxide (slaked lime). Ca is an essential nutrient for the building and maintenance of a healthy bone structure. Calcium in hard waters can contribute significantly to the required daily calcium intake. Health effects include: Large amounts of calcium are required for the maintenance of a healthy bone structure and, at the concentration normally found in surface water, calcium has a beneficial health effect. In sensitive individuals, high levels may contribute to the incidence of kidney stones. Aesthetic effects include: Calcium generally imparts a pleasant taste to water, except at very high concentrations, where the water tastes “hard”. At elevated levels, Ca, causes scaling (together with Mg) in distribution systems and appliances. Where calcium is absent or in low concentration “soft” water, corrosion may occur in distribution systems and appliances. Treatment: Calcium can be removed by cation exchange softening, which replaces calcium with sodium, or by demineralisation techniques such as ion-exchange. Chemical precipitation and sedimentation are most frequently used when large volumes of water are tested. Home-treatment Ion-exchange kits are available to treat small volumes of water
  • Chloride (Cl-)
    Chloride is a negatively charged anionic component of table salt (Cl-) formed when Chlorine gains an electron, or when a compound such as hydrogen chloride is dissolved in water. Chloride salts such as sodium chloride are very soluble in water. The concentration of chloride ions is often elevated in hot, arid areas and on the western and southern coast of Southern Africa, particularly in groundwater. Elevated Cl- levels impart a salty taste and accelerate the corrosion of metals. Health effects include: High levels of chlorides may result in nausea and vomiting. Aesthetic effects include: Chloride increases the electrical conductivity of water and its corrosive impact. In metal pipes, Cl- reacts with metal ions to form soluble salts, increasing the level of metals in drinking water. Water with high concentrations, above 1200 mg/L, of Cl- imparts a salty taste and may cause nausea and vomiting. Additional effects may occur in sensitive individuals disturbing the salt/water balance, resulting in possible complications for those with congestive heart failure or hypertension. Treatment: Chloride is difficult to remove from water and requires energy-invasive processes, such as; resin ion-exchange demineralisation, reverse osmosis, distillation and electrodialysis. These processes require high operator skills, maintenance and continual monitoring.
  • Copper (Cu)
    Copper is an orange coloured metal that is a good conductor of heat and electricity. Cu is needed in small quantities for the integrity of the fatty covering of nerve fibre sheaths. Health effects include: Copper does not generally have negative health effects, but can be detrimental to sensitive individuals with Wilson’s Disease. At high enough concentrations, Cu can cause nausea and vomiting and acute kidney and liver damage. Aesthetic effects include: High concentrations that are greater than 1 mg/L where pH is low, corrode copper pipes in distribution systems, leading to a characteristic blue/green appearance of water. A predominant metal taste is experienced in water with concentrations of copper above 1 mg/L, including green staining on clothing, fixtures and light hair colours. Treatment: Adjusting pH to values of between 6-7 and flocculation with aluminium or ferric salts. Higher concentrations may require lime and copper precipitation as copper hydroxide at alkaline pH. Ion-exchange is typically used in residential settings and for small volumes of water. Reverse osmosis, ion-exchange or distillation systems are able to remove ionized and dissolved ammonia forms.
  • Chromium (Cr)
    Chromium is an element found in air, water, rocks, soil, gases, and volcanic dust. Pollution from steel and pulp mills, industrial waste, natural eroding deposits, and water from cooling systems are sources of chromium in drinking water Health effects include: High levels of chromium are considered very dangerous when found in water. Continual ingestion and exposure to chromium can lead to health impacts. Chromium-6 is considered a carcinogen (cancer-causing) when ingested or inhaled. Chronic exposure is known to increase lung cancer, intestinal and major organ damage to livers, kidneys and nerves. Several adverse effects include serious skin irritation, rashes, contact dermatitis, and allergic reactions. Treatment: Removal of chromium from drinking water can be achieved by filtration, ion-exchange and reverse osmosis. Chromium levels should be continually monitored to ensure adequate treatment.
  • Iron (Fe)
    A common indication of high iron appears brown or black, due to oxidation of the metal’s surface. The reddish colour of soil is due to iron. Iron is an essential micro-nutrient needed for the formation of haemoglobin (oxygen-carrying blood). Dissolved iron is found in water due to dissolution from soils or sediments under anaerobic reducing conditions. Normal levels of iron in unpolluted fresh water range from 0.001 – 0.5 mg/L. Pollution can occur from acid-mine drainage. Health effects include: Intake of high levels of iron can result in acute poisoning in infants and young children. Eventual chronic poisoning - haemochromatosis can occur over a prolonged period of excessive daily iron intake. Aesthetic effects include: At concentrations normally encountered in water, iron has an aesthetic rather than toxic effect. Iron imparts a metallic taste to water, as well as a brownish discolouration. Treatment: Where water has low organic content, iron is uncomplexed (groundwater), aeration of the water may be effective in precipitating the iron from the solution. Conventional coagulation and flocculation techniques, with strong oxidant and treatment, if necessary, with lime, are usually effective in removing iron from water. Complexed iron, requires the use of strong chemical oxidants and lime treatment. Home treatment kits using ion exchange can be purchased to treat small volumes of water.
  • Magnesium (Mg)
    Magnesium is an alkaline earth metal that burns with a brilliant light (used in flares) to form magnesium oxide. Magnesium hydroxide is well known as a stomach antacid, in the form of Milk of Magnesia and magnesium sulphate in the well-known purgative “Epsom salts”. Mg is an essential element needed for the normal functioning of muscles. In unpolluted water, the concentration of Mg is less than 10 mg/L, except in some groundwater where levels may rise to several hundred mg/L Health effects include Suppression of the central nervous system, is rarely seen due to the bitter taste effect high levels of Mg create. The most common health effect of high levels of Mg is diarrhoea, where Mg is found in association with Sulphate (SO4). Aesthetic effects include: High levels of Mg impart a bitter taste to water. Magnesium causes scaling (together with calcium) in distribution systems and appliances Treatment: The most common treatment is lime softening followed by re-carbonation. Other techniques include ion-exchange resins or precipitation at high pH. These methods require skilled operation and high maintenance and monitoring. Home treatment kits using ion exchange can be purchased to treat small volumes of water.
  • What are Nitrates? NO3 as N
    Nitrate is a Nitrogen ion with the formula NO3-. This is the end product of oxidation of Ammonia NH3 and NO2 (Nitrite). Nitrate and nitrate can be readily converted from one form to the other. Nitrates result from the decay of plant, animal and human waste as well as pollution from industry and large-scale agriculture. Health effects on Humans and Animals: Water with high concentrations of NO3 is harmful to humans and animals. Once absorbed into the blood, NO3 ions are changed into NO2 ions. Potential to cause tiredness and failure to thrive, this can be chronic. Chronic effects can occur in infants under the age of 1 years old, this includes: cyanosis and blue-baby syndrome. Treatment: Ion exchange (used to treat small volumes of water), reverse osmosis and biological reduction using a carbon source. While effective biological reduction is used in treating large volumes of water and is difficult to optimise and maintain.
  • Nitrates effects on bodies of water
    Farmers use fertilizers high in Nitrates. Heavy rains wash excess nutrients that are not readily used by plants into nearby rivers, dams or leach into the ground water. Excessive levels of nitrates in water may cause aquatic eutrophication. The Nitrogen (N) present in nitrate ions is a source of aquatic plants and blue-green algae. High levels of nitrates may result in increased growth of aquatic plants and algae, making the water “green”. Some species of blue-green algae produce poisons. The Nitrogen (N) present in nitrate ions is a food source for aquatic plants and blue-green algae. High concentrations of nitrates in water may cause increased growth of aquatic plants and algae, resulting in eutrophication. This is excessive growth of blue-green algae making water green. Some species produce poisons and make water green. Once these aquatic plants die, large numbers of decomposing bacteria result. These bacteria use up the oxygen in the water causing aquatic species (fish and plants) to die. Nitrate supplementation through sewage contamination and fertilizer run-off is not as critical as it is with Phosphates (PO43-) as aquatic species are not as sensitive to increased levels. Nitrate and ammonia (NH3) are important components of most fertilizers. Nitrogen normally occurs in a form that plants cannot use, however, it may be used in the decomposition of dead water plants and by blue-green algae which can convert nitrogen gas in the air into ammonia and nitrates that plants use. Nitrate ions are also a result of urea contamination (urine).
  • Chloride (Cl-)
  • Sulphate (SO4)
    Sulphate concentrations in unpolluted water are typically less than 10 mg/L. In areas where acid mine drainage and effluent pollute, the water concentration can rise to 500 mg/L or more. Health effects include: Acute effects, causing diarrhoea, adaption can occur naturally. Aesthetic effects include: A distinctive bitter taste and “rotten egg” smell may occur due to hydrogen sulphide. Treatment: includes ion exchange with resin, desalination processes or precipitation with calcium salts followed by settlement and filtration. Precipitation treatments require high operational and maintenance skills. Ion-exchange is typically used in residential settings and for small volumes of water
  • Nickel (Ni)
    Nickel concentrations in groundwater depend on soil use, pH and depth of sampling. Acid rain additionally increases the mobility of nickel in the soil and thus in groundwater. Increased levels of nickel in municipal water and groundwater are additionally reported in areas of high pollution. Health effects include: Individuals who accidentally drank light-green water containing 250 ppm of nickel from a contaminated drinking fountain had stomach aches and suffered adverse effects in their blood (increased red blood cells) and kidneys (increased protein in the urine). Treatment: Most systems with carbon block cartridges, granular activated carbon cartridges, and thin film composite membranes will reduce nickel levels in drinking water, like countertop, reverse osmosis, under sink, and most Everpure systems.
  • Uranium (U)
    Uranium is a common radioactive element that exists naturally all over the world. In its pure metal form, uranium is silver with a grey surface. It’s the heaviest naturally-occurring metal, and it’s almost as strong as steel. Naturally occurring uranium in well water comes from dissolving or eroding soils and rocks that contain uranium. It’s more likely to have higher levels in drilled wells when the water flows from cracks or fractures in bedrock than in shallow dug or bored wells and surface water supplies. Health effects include: People might be exposed to uranium when they breathe, drink water, or eat food from areas that have high background levels of uranium. You can’t see, smell, or taste uranium. You must have your water tested to find out how much uranium is in it. After uranium is ingested or inhaled, it gets into the blood fast and collects in the kidneys and bones. Uranium leaves the body very slowly when people pass urine and have bowel movements. The main health concern when people are exposed to uranium is kidney damage. Radiation from high levels of uranium is not known to cause cancer. Treatment: Reverse osmosis, distillation and anion-exchange systems can be used to treat Uranium. Constant monitoring of water after filtration should be done to ensure levels remain low.
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