Water is the most basic requirement and no one on this earth can live without water. Besides used for drinking water is also an important ingredient in foods and food preparations. Manufacturing units and food establishments get their water tested from food testing laboratories to ensure that it is free of hazardous contaminants. Water testing is important for them as the quality of drinking water can affect the quality of their products.
Contaminated drinking water is considered a health risk leading to a number of waterborne diseases. Water is regulated by the Bureau of Indian Standards (BIS) and the standard quality for safe drinking water in India is – IS: 10500.All drinking water sources should be tested regularly to determine that it is meeting the BIS specified standards. Drinking water testing also identifies the extent of contamination/ unacceptability so that the shortcoming can be remedied. In 2012, BIS added a new standard which was that water distribution systems, including consumer premises should be free from viruses. This necessitates drinking water testing for viruses to remain within the BIS standards.
Drinking water can be polluted in a number of ways during storage and through mode of transportationwhere leaks have developed. Microbiological testing of water is required because water can come in contact with human faeces which can contaminate water with coliform bacteria. Water borne diseases are preventable, yet contaminated drinking water can cause several health issues like gastroenteritis, dysentery, cholera, diarrhoea, jaundice and even death. Microbial water testing detects the presence or absence of E. coli bacteria and total coliform bacteria for which the parameter is Nil.
Besides microbiological pathogens, drinking water can be contaminated with heavy metals from the environment, pesticides from agricultural use and other organic compounds. All these chemical and metal contaminants can get lodged in the body tissues, leading to serious long term health issues like cancer. Chemical testingparameters are carried out for total hardness, alkalinity, chloride, fluoride, sulphate, nitrate, sulphide and cyanide and for heavy metals like mercury, cadmium, arsenic, lead, aluminium, nickel and boron.
The standards for drinking water clearly lay down the requirements in terms of the acceptable limit and the permissible limit for each of the test parameters. Water samples are required to comply with the acceptable limits whereas permissible limits are only applicable if there is no alternate source of drinking water. The drinking water testing parameters include besides odour, taste; the physical testing parameters like colour, turbidity, pH value and Total Dissolved Solids (TDS).
Establishments like schools and hostels, hospitals and hotels as well as housing societies regularly get their drinking water tested in food testing laboratories so quality of water is maintained. Any housing near industrial areas or manufacturing plants also require regular water testing as water can get contaminated with toxic heavy metals and pesticides in such areas. Regular analysis in water testing labs can help identify the source of leaching and contamination and can then be rectified.