Pure myth

Talk about his company's fortunes is likely to elicit a beaming smile from Mahesh Gupta. Kent RO systems' managing director says that his company's profits grew 40 times between 2002-2003 and 2007-2008 from Rs 2.5 crore to Rs 100 crore. Other water purifier manufacturers also say that business is good. Are they making tall claims? Or are they making hay while the sun shines?

Actually a bit of both. There is little doubt that the water purifier market is growing. But accurate market size figures are hard to come by. A 2005 study by us- based consultancy firm Frost and Sullivan notes that one in every 40 Indian households uses water purifiers. R S Rajan, vice president consumer marketing of the Mumbai-based Ion Exchange, says that water purifier penetration in the country ranges from 25 per cent households in Delhi to 0.42 per cent in cities in Bihar (see graph For clean water. There is also no unanimity on the value of the market.Ion Exchange puts it at Rs 800 crore, Frost and Sullivan says it is worth Rs 1,400 crore and Eureka Forbes pegs the figure at a little more modest Rs 1,000 crore.

Market share figures are similarly obfuscating there is no government data, and claims of different companies simply don't add up. For example, Kent's claim of a 40 per cent urban market share would not hold much ground if Eureka Forbes' contention of a 70 per cent market share is found to be accurate.

Rajan puts the issue in perspective. "Market research is tailormade," he says.

Frost and Sullivan does say that "Eureka Forbes, Kent RO, Usha Brita and Ion Exchange are the biggest operators in the Indian water purifier market." But the us- based consultancy also points to another significant player the unorganized sector with a 45 cent share in the market.

Spoilt for choice?
S Mushtaq Khan of Frost and Sullivan says, "Ultraviolet (uv)- based systems dominated the market in 1990s. Reverse Osmosis (ro) systems are gaining acceptance though they are costlier," he says. Pritee Shah, editor of the consumer magazine, Insight concurs. "Marketing stunts have created the impression that water can only be purified by the reverse osmosis (ro) system," she says (also see box A film star speaks).

For clean water

Penetration of household water purifiers

Source R S Rajan, vice president, consumer marketing, Ion Exchange India Limited, Mumbai, personal communications, February 20, 2008

Most water purifiers today combine two or more treatment processes. These include ro, uv, filteration and disinfection technologies. Industry insiders point out that Eureka Forbes, conventionally known for uv- based systems, has integrated ro and carbon filtration into its products. Frost and Sullivan says that 51 per cent of the purifiers in India are uv- based while 42 per cent are ro systems and the rest candle and resin filters. This is going against the global grain where ro- based systems hold just 11 per cent of market share.

But are ro systems suited for Indian conditions? C K Sandeep, associate vice president Ion Exchange says, " ro is not needed at places where total dissolved solids are less than 500 mg/l. In such conditions ro systems are very likely to rob the water of essential minerals ." Other critics talk of the huge water wastage 60-75 per cent water goes waste with ro systems.

Such inefficiences have not been addressed by recent innovations. Most of them have been cosmetic. Innovations on operation and maintenance come at a cost. ro systems require cleaning every three-six months. Membranes have to be replaced every one-and-a-half to two years. Normally, first year servicing is free while subsequent services have to be paid for charges range from Rs 1,200 to Rs 3,600 based on the product.

A water purifier has to deal with physical, chemical and biological adulterants including dissolved solids, heavy metals and pesticides. Besides, all contaminants have different characteristics like molecular weight and size, water solubility, volatility and ability to react with oxygen. So, water treatment is a multi-pronged process, and the contaminant challenge has a big say in selecting appropriate technology.

Treatment processes either remove contaminants or destroy them. Removal technologies include ion exchange, adsorption and filteration (see flow diagram Water treatment). Then there are technologies that decompose chemicals and pesticides by oxidation or hydrolysis. Chlorination, for example, is also known to oxidize and remove many pollutants. Disinfection is a similar technology.

Let us now see how most common filters work

Activated carbon filter
These filters follow a two-pronged approach.Firstly, some contaminants are blocked by pores--filters with small pores are more effective. Secondly, these purifiers have carbon filters which draw molecules from dissolved contaminants--this process is called adsorption. Characteristics of the carbon material--particle and pore size, surface area, surface chemistry, density and hardness--influence the process's efficiency.

In many household filters, carbon's adsorbing powers are enhanced by adding a slightly-positive electrical charge. As water passes over the positively charged carbon, the negative ions of the contaminants are drawn to the surface of the carbon granules and are removed.

Activated carbon filters typically use granular carbon or blocks of powdered carbon. The latter remove more contaminants, including volatile organic chemicals (vocs), pesticides and herbicides, chlorine, and other chemicals found in tap water. It also removes unpleasant taste and odour. However, some heavy materials and bacteria can slip through the filter cartridge if the carbon is not densely-compacted. Carbon filters need recharging.

Ion-exchange filters
Ion-exchange is mostly used to remove hardness in water caused by carbonates and bicarbonates of calcium and magnesium. These filters have a resin bed, which draws out calcium ions and magnesium ions in water and replaces them with sodium ions.

Water purifiers must address the contaminant challenge

Ion-exchange filters can remove iron, lead, copper, barium, radium and nitrates. Some such filters can also remove arsenic and selenium. Suraksha, one of India's earliest tap filters, used the ion-exchange process. Now, most filter manufacturers prefer integrating ion exchange into a system that has several water purifying technologies.

Reverse osmosis filter
ro uses pressure to force water through a membrane that retains the contaminants on one side and allows the pure water to pass to the other side (see diagram How reverse osmosis refines water at a micro level)

Enlarge view

ro purification units involve two processes. The unit consists of two filters a carbon or sediment filter, also called pre-filter and a semi permeable membrane. The pre-filter removes large particles from the water before it passes through the semi permeable membrane.

The membrane allows water to pass through, but traps pollutants and bacteria in its porous surface. Some ro systems also have a uv disinfectant which rids water of microbiological contaminants. The flow rates of these household filters vary from 8 to 72 litres per hour

Today, reverse osmosis has become very popular and its proponents claim that ro can remove virtually every contaminant. But that's a myth.

RO filters waste 60-75 per cent water

Complicated mechanism
A lot of systems combine a variety of filters
Source www.espwaterproducts.com as viewed on February 28, 2008

who says that ro systems cannot completely remove some pesticides like lindane, solvents and other vocs.

The cost of household ro filters range from Rs 9,000-Rs 46,000 and they are heavy on maintenance.The pre filters and the ro membranes must be changed according to the manufacturer's recommendation. The storage tank must be cleaned periodically. Damaged membranes are not easily detected, so it is hard to tell if the system is functioning normally and safely (also see box Think before you use ro).

There are other negatives. As the water free of contaminants passes through the membrane, highly concentrated wastewater is discharged. 60-75 per cent of the water is rejected in an ro system. The amount of water rejected by the system depends on the quality of raw water, particularly its dissolved solid content

Ultra Violet light disinfection systems
In such filters, water is passed through a clear chamber where it is exposed to uv light, which destroys bacteria and viruses. uv lamps found in filters in the Indian market last 5,000 to 10,000 hours of operation.

The system's efficacy depends on the resistance of an organism. If the energy dose is not high enough, an organism's genetic material might only be damaged--and not disrupted. This means the organism would remain and can regenerate in suitable conditions. uv cannot be a stand alone treatment process because water has multiple contaminants.

A water purification system must have a high quality carbon filter or a reverse osmosis system if it has to contend with heavy metals and chemicals. uv filters are employed as the final purifier in some systems.

Some advantages of uv filters are

It does not introduce any toxic or significant nontoxic byproducts
Does not alter smell or taste of treated water. In fact, it actually improves the taste of water taste by destroying organic contaminants
Does not affect minerals in water
Cleanses in seconds (chemical disinfection takes several minutes).

The system's disadvantages are
It is not suitable for turbid water with high levels of suspended solid or soluble organic matter. This can react with uv radiation, reducing the quality of disinfection
uv light is also not effective against soluble salts, pesticides, heavy metals, manyorganic chemicals and chlorine.

The best technology
Marketing gimmicks have created the impression that ro is the most effective technology to remove pesticides and other toxins from water. Kent RO systems, for example, has come out with a purifier which claims to adjust dissolved solid levels and minerals in water by a mere turn of a knob.

However, the third edition of who's guidelines for drinking water quality point out that more conventional technologies like activated carbon and ozonation are most suitable for removing pesticides and other organic chemicals.

The guidelines show that activated carbon is more effective for removing most pesticides (see table Cheap technologies do well). who also has a system to rank water purifiers according to their complexity and economics. Activated carbon and ion exchange are ranked the highest, while membrane treatment is deemed the most complex and costliest.

Cheap technologies do well
In removing pesticides
Note + stands for limited removal of the contaminant; + + for 50 per cent removal and triple plus for 80 per cent removal Source Anon 2003, Guidelines for Drinking Water Quality, 3rd Edition, World Health Organisation, Geneva, October

Integrating technologies
Integration of different technologies is more efficient in dealing with a complex pollutant matrix. And in fact, lot of modern day filters integrate different processes.

A typical system is shown in the diagram it is basically a reverse osmosis system, which employs pre-filter mechanism to remove odour and taste impurities. At this stage, some chemicals--up to about 0.2 micron--are also removed.

The water is then passed through ro membranes. At this stage concentrated waste is discharged and fresh water is passed through another filter to remove any contaminant--chemical or microbial--that would have escaped the ro membrane's pores.

Some systems employ uv light at the end of the treatment chain to get rid of bacterial contaminants.

A consumer looking for a water purifier is most likely to be confronted with a fusillade of quality claims. K J Nath, president, Institution of Public Health Engineers in Kolkata is not sure about their veracity. "A lot of the tall claims by private players cannot be substantiated scientifically," he says.

Down To Earth asked a few manufacturers about the standards they adhere to. Most produced lab reports and rolled of terms like certified by nsf international usa, endorsed by the Indian Medical Association (ima), tested by university of Minnesota, bis certified, member of the Water Quality Association, usa.

What about the testing criteria at these national and international laboratories? We wondered. Our investigations revealed that these varied and were sometimes even irrational. A consumer needs to know the contaminant challenge, the quality and source of water, for which the purifier was certified. But consider, for example, a 2006 report by Spectro Labs Delhi. It stated that a model manufactured by Kent cleansed to packaged drinking water standards IS 14543 2004. Heavy metals were within limits stipulated by this standard, the report noted. But most heavy metals were within prescribed limits in the untreated water itself. So, the purifier had actually done precious little. It had only removed microbial contaminants, tds and salts. IS 14543 2004 standards also stipulate that there should not be any pesticide in water. But the Spectra Labs report made no mention of pesticide levels in the treated water.

We then decided to check on certificates issued by the Indian Medical Association. Were they also indifferent to the contaminant challenge? A certificate given by the association to Eureka Forbes in 2004 came as a revelation. It showed that the association actually does not test water purifiers. The certificate said, "Endorsements....(are) issued after examining all quality certificates obtained... from various labs and being satisfied about the same. ima endorses and approves the range of products mentioned above as being in conformity with the international standards for providing safe drinking water."

Standards don't account for changes in pollution profile

There are hundreds of other companies who claim substantial contaminant removal without any backing or certification. It is high time regulations were laid down to help the consumer make an informed decision.

Vacillating bureau
The Bureau of Indian Standards (bis) does have standards for some water purifiers like uv filters and candle filters. But these standards were developed between 1979 and 1999, when it was believed that water purifiers were meant to remove only bacteriological contaminants (see table Outdated and inadequate). Besides, these standards only apply to water that is free of chemicals and suspended matter. But as Nath points out, "Besides removing faecal coliform, water purifiers must also get rid of viral and parasitic pathogens as well as toxic chemicals like arsenic, fluoride and pesticides."

More importantly, the most sought after ro systems are outside the pale of standards.

Within the bis there is some awareness that the standards have not kept pace with changes in technology and pollution profile. The issue was, in fact, raised at the bureau's sectional committee meet on drinking water standards on February 5. But the priority seemed to be on revising drinking water standards. Prakash S Kelkar, chairman of the committee who also heads the Nagpur-based National Environmental Engineering and Research Institute's geo-environmental monitoring division said, "Drinking water standards (IS 105001991) in the country are much lenient compared to that set by the who or the us Environmental Protection Agency. Once we zero in on drinking water standards, we can move on to discussing norms for water purifiers." He did, however, suggest that "the first step towards setting standards is to have an independent and comprehensive assessment of the performance and claims of various filters."

Water purifier standards are also snagged because the bis can't seem to decide which of its divisions should take up the matter. Standards for uv filters were developed by the bureau's hospital equipment sectional committee, while those for candle filter were developed by ceramic ware sectional committe e. But there is no agreement on who should frame comprehensive standards in view of the changing market and the changing pollution profile (see box bis standard on drinking water).

What shall be the standards?
bis can draw lessons from international standards. A good example is the us standards drawn up by the ngo, NSF International. Water purifiers are certified for nsf standards by another not-for-profit group, the Water Quality Association. There are seven standards that cover a range of technologies and their performance claims. There are two sets of standards for carbon and ceramic systems that address health and aesthetic parameters.

Outdated and inadequate BIS standards on water purifiers need a revision Standard Salient features IS 147241999 Water purifiers with ultra violet disinfection Applicable to systems which rid water of water-borne pathogenic bacteria and suspended matter. Cannot filter dissolved solids or chemicals IS 74021986 Specification for filters for drinking water purposes Covers ceramic candle filters that remove suspended matter and bacteria. Cannot filter dissolved solids or chemicals. Materials used to make the filter should not mar drinking water safety. Filters must have information on the amount of water it can purify before it has to be cleaned IS 93101979 Specification for water purifier (electrically heated) Covers potable water purifier used for consumption in dispensaries, hospitals and in medicine preparation. Labels should contain instruction to boil water for minimum 30 minutes

The standards address the following issues

Product material safety The standards ensure that the product does not add any contaminant to water

Structural integrity The purifiers can work under high pressure

Literature and labelling They stipulate that there should comprehensive guides to aid installation, operation and maintenance. They also require that manufacturers corroborate performance claims with data sheets

Contaminant reduction claims A water purifier need not clean water of all contaminants. But manufacturers must specify the contaminants their products can check. There are different standards for different contaminant challenges. For example, standard number 53 applies to carbon and ceramic filters. Water purifiers can claim adherence to this standard if they cleanse 95 per cent of 300 parts per billion coliform. Pre-and post filters in an ro system must also be certified seperately.

Industry sources exude confidence about the water purifier segment. Manufacturers peg their hopes on the increasing purchasing power of the middle class in cities, small towns and the suburbs.

The water filter market thrives on a vicious circle. With municipalities failing to provide safe potable water, many turn to groundwater; overextraction affects water quality and water purifiers become the last-resort choice.

Most people who resort to water purifiers do not even have information on water quality. It also doesn't help that there are no laboratories where people can test water.

At the same time, bis and the ministry of consumer affairs have to fix standards for the water purifier industry in ways suited to Indian conditions. The product should be verified for its contaminant removal claims over its life span and also be tested for material safety.Labeling is another important requirement manufacturers should be accurate in describing which contaminants their product can remove and to what extent. Operational and maintenance details must also be specified. Standards should deal with the applicability or the necessity of technologies in different conditions.

Norms to cut down water wastage must be laid down, especially for ro systems.

But purifiers cannot solve the problem of bad water quality. At best, they can offer partial solutions. Water purifiers are for the rich. It is no surprise that Delhi and Mumbai which have a huge population of rich and middle classes are the biggest markets for water purifiers.

We can't first pollute water and then clean it up

Our municipalities must also get their act together. The current system only encourages wastage 30-60 per cent of treated water does not reach the consumers. Also it is estimated that urban India will invest Rs 69,000 crore in the next five years on water supply projects. The eleventh Five Year Plan also projects that urban water supply systems would on average spend Rs 8,300 crore annually on operation and maintenance--almost 1.4 times higher than the tenth plan. Funding might take care of capital costs. But recovering operation and maintenance costs will be an enormous challenge. The Delhi government, for instance, charges Rs 2 for a kilolitre of water as against the Rs 9-10 spent on supplying it to households.

But providing water to the poor becomes a convenient alibi for subsidizing the rich. The supplies don't reach the poor who have to pay more for arranging supplies, while the rich waste water.

It is high time we thought of those who are not serviced by municipalities and also cannot afford purifiers. Safe drinking water has to become the legal right. bis must set a legally enforceable standard for drinking water.