TURNING THE RIGHT TAP ON
There is a need for more sophisticated methods to ensure safe drinking water
Water is an essential part of food. We need at least two to three litres of it every day. But it is still a daunting task to provide access to clean, safe water not just in villages but to all living in cities and towns.
Though access to drinking water in India has increased over the past decade, adverse impact of unsafe water on health continues. The World Bank estimates that 21 per cent of communicable diseases in India are water related. Of these diseases, diarrhoea alone killed over 700,000 Indians in 1999. The highest mortality from diarrhoea is in children under the age of five, pointing to an urgent need for in- terventions to prevent diarrhoea disease in this age group. Diarrhoea is caused due to ingestion of pathogens in water and food. Eighty- eight per cent cases of diarrhoea are due to drinking unsafe water. Diseases such as cholera, typhoid and dysentery are related to oral faecal transmission.
Besides contamination of water with harmful bacteria such as Escherichia coli and viruses, water sources are mixed sometimes with industrial effluents, heavy metals, pesticides, nitrates, arsenic, cadmium and fluoride. Drinking water containing heavy metals can result in damage to the kidneys and the nervous system. Excess fluorides in water can cause yellowing of teeth, damage to the spinal cord and crippling disease affecting the functioning of limbs. In India, the most common cause of fluorosis is fluoride present in water— particularly water from bore wells. As many as 17 states have been identified as ‘ endemic’ areas for fluorosis with an estimated 25 million people afflicted and another 66 million at risk. The disease affecting the teeth is known as dental fluorosis and that affecting the bone is known as skeletal fluorosis.
A knowledge, attitude, behaviour, practice survey reported by the National Institute of Nutrition ( NIN) observed that only one in three people have protected water supply. The survey also revealed that 40 per cent of the households purify water at home using methods like straining through cloth. Other methods used are boiling water, chlorine tablets and water filters.
The standards for potable water are prescribed by the Bureau of Indian Standards ( BIS). However, adoption of BIS standards is voluntary, not mandatory. Packaged drinking water is regulated by the Food Safety and Standards Authority of India Act, 2006.
Most water that is available is packaged drinking water and not mineral water. The packaged water is that which is safe for human consumption. In contrast, mineral water should contain certain essential minerals in the stipulated values as it is intended to offer some therapeutic effect. There are a few brands that produce mineral water but these are expensive when compared to packaged drinking water.
What needs to be underscored is that clean, healthy water does not have to be pure but potable and of such quality so as to keep healthy those drinking it. There is a need for more sophisticated methods of ensuring safe drinking water while still reducing the need for chemical treatment and identifying potential hazards more quickly.
Director, National Institute of Nutrition, Hyderabad
Dr Kalpagam Polasa