The study evaluates and compares the quality of drinking water from different sources, available for consumption in holy city of Mathura. Total 180 water samples from household sources, public places and packaged water were subjected to physico-chemical and microbiological analysis. The odor and color of all the samples were within the acceptable limits. The pH, Total Dissolved Solids (TDS) and Standard Plate Count (SPC) range was 6.5-8.9, 20-2000 ppm, 0-105 cfu/ml, respectively. Total coliform count ranged from 0 to >1800 Most Probable Number (MPN) per 100 ml of water at 37oC. High counts upto 130 coliforms/100 ml were observed in locally packaged water whereas no coliforms were found in reputed brands. Overall prevalence of E. coli in samples was 10.56% (19/180), with highest prevalence in drinking water available at public places (21.67 %). No E. coli O157:H7 could be isolated. The difference in various parameters was statistically significant (p<0.05) when compared with BIS and WHO. Drinking water available at homes and at public places did not meet the WHO standards for drinking. RO and packaged water were found safe and within the standards.
Water is essential for sustenance of all living organisms, ecological systems, human health, food production and economic development (Postel et al., 1996). The declining availability of fresh, pure drinking water is one of the most important environmental issues faced by various countries at the present time. Potential of drinking water to transmit microbial pathogens to populations, causing diseases is well known in countries at all levels of economic development (Payment et al., 1991). About 800 million people in Asia and Africa are living without access to safe drinking water, exposing them to various diseases (Tanwir et al., 2003). Disease burden from unsafe water, sanitation and hygiene (WSH) accounts for 5.3% of all deaths and 6.8% of all DALYS all over the world (Pruss-Ustam et al., 2002). Despite wealthy economies and access to proven drinking water-treatment technologies, significant outbreaks of waterborne intestinal diseases have also occurred in developed countries of North America and Western Europe over the last 10–15 years (Pons et al., 2015). In 2011, around 768 million people relied on unsatisfactory water supply having high levels of pathogen contamination (WHO and UNICEF, 2013). The pollution in available water is continuously increasing due to changes in the modes of industrial activities, agricultural production, and increasing urbanization (Aremu et al., 2011).
Ideally, drinking water should be free of any seen or unseen impurity, pathogenic microorganisms and other contaminants which could harm the health of people. The safety of drinking water can be monitored in a number of ways because the constituents in drinking water (chemicals and microbes) which can compromise human health can be measured directly but in reality, such water monitoring technologies are not yet at the stage of development that would enable their widespread use for routine drinking water testing. The essential parameters of drinking water quality are fecal E. coli and total coliforms, residual chlorine, turbidity, pH, dissolved oxygen content, temperature, total suspended solids (TSS), total dissolved solids (TDS) and heavy metals (WHO, 2011; WHO, 2003; Dissmeyer, 2000). Traditionally, microbial safety of drinking water has been confirmed by monitoring for absence of microorganisms of faecal origin called the indicator organisms (Le- Chavalier and Au, 2004). E. coli is considered a suitable indicator as being almost exclusively fecal in origin, indicates recent faecal contamination (Leclerc et al., 2001; Parul et al., 2014). There should not be any E. coli or coliform detectable in treated water sample (WHO, 2011a). Various waterborne outbreaks have been reported all around the world implicating E. coli but still there is lack of credible information regarding the prevalence of these bacteria in drinking water especially in developing country like India. Several studies have been conducted to assess the quality of drinking water in India and abroad as it is very essential to monitor the water quality (Mishra et al., 2012; Patil et al., 2012; Sulehria et al., 2012; Karketta et al., 2013; Tsega et al., 2013; Deshmukh and Urkudu, 2014).
Mathura in Uttar Pradesh is a major tourist destination in India with lakhs of both foreign and domestic tourists visiting this place. At any given time, the floating population is much more than the actual people residing in this area. This creates added burden on the available water resources in the region which already faces considerable water problems. Thus a study to assess the faecal as well as physico-chemical contamination level in groundwater of the region is the need of the hour.
Materials and Methods
Study Area and Sampling
The present investigation was conducted in the holy city of Mathura (latitudes 27.41o North and longitudes 77.41o East) with a population of 2541894 and an area of approximately 3329.4 kms. A total of 180 drinking water samples (60 household water samples including 30 tap or supply water and 30 Reverse Osmosis (RO) water samples, 60 samples of water available for drinking at public places including 30 samples each of water from restaurants and schools and 60 packaged water samples (30 samples each of bottled water and sachet water) were collected aseptically from December 2013 to December 2015, brought to laboratory on ice in 500 ml sterile glass bottles (Axiva), and processed within 4-6 hours (Park, 2011).
The pH of the water samples was determined by the Hi Media pH indicator paper strip (HiMedia, Mumbai) at the site of sample collection. The taste was analyzed by a panel of people at the Department of Veterinary Public Health, COVASc , DUVASU, Mathura. Total Dissolved solids (TDS) of the water samples was determined by water and soil analysis kit (Model No –LT-61-Scientech Lab Pvt Ltd Delhi) and results expressed in mg/l (APHA, 2005) .
Standard Plate Count (SPC) and Coliform Count
The SPC and Coliform Count using multiple dilution technique of all water samples were performed as per the standard methods (Edward and Ewing, 1972; Cruickshank et al., 1975; APHA, 2005). The readings of the samples were compared with the standard readings recommended by WHO (1984) and BIS (2003).
The data were subjected to statistical analysis using Statistical Package Social Science (SPSS) version 16 software, packaged and developed as per the procedure of Snedechor and Cochran, (1989). Duncan’s multiple range test (Duncan, 1955) were determined at 5% and 1% level of significance.
Isolation of E. coli
All the 180 drinking water samples were processed for isolation of E. coli within 4-6 hrs of sampling according to Sojka (1965) and Edwards and Ewing (1972). After Enrichment in modified Trypticase Soya Broth (mTSB), it was streaked onto MacConkey Lactose Agar (MLA) plates. Lactose fermenting pink, smooth round colonies were further streaked onto Eosin Methylene Blue (EMB) agar plates (selective plating) and clear blackish colonies with unmistakable greenish metallic sheen tentatively considered to be E. coli, further confirmed by morphological (Gram’s staining technique) and biochemical characteristics (Ewing, 1986; Ahmad et al., 2009) (HiMedia Rapid Biochemical Identification Kit). All the biochemically confirmed E. coli isolates were streaked onto MUG-Sorbitol agar (HiMedia) and incubated at 37oC for 24 hours. Colonies showing non fluorescence under ultraviolet rays were tentatively considered to be E. coli O157:H7.
Results and Discussion
Water is necessary for all ecological systems, human health, food production and economic development (Shafiq et al., 2013). The available water is increasingly becoming polluted due to increasing human population, industrialization, agricultural practices etc (Patil et al., 2012) and can cause various ailments and other health related problems in animals and humans. E. coli are highly specific indicator for fecal pollution caused by feces of man and all warm blooded animals as they cannot multiply in natural water environment. This is a preliminary study to assess the quality of drinking water available in Mathura by subjecting the water samples to various physico-chemical (pH, taste, color, odor and TDS) and microbiological parameters (SPC and coliform count) as well as isolation of E. coli. Taste of all samples of RO and packaged water was sweet and agreeable whereas 93.3% (28/30) of tap water samples, 63.3% (19/30) of restaurant samples and 73.33% (22/30) of school water samples were salty. Taste of water is influenced by presence of minerals, metals and salts from soil and products from biological reactions. Water tastes bitter when contaminated with alkaline impurities and salty when metallic salts are present. Pure water is colorless but natural water is often colored by foreign substances like tannic, humic acid etc, present in the organic debris (leaves, woods etc) (Dodoo et al., 2006) whereas odor might be due to biological degradation. None of the water samples had any sort of disagreeable odor and color anytime during the investigation period. A detailed analysis of physical attributes of drinking water has been done by Mohsin et al. (2013) with respect to odor, color and taste of drinking water in Bahawalpur City, Pakistan.
pH is the scale of alkalinity of water and measures concentration of hydrogen ions (Gupta et al., 2013).Water with lower pH is corrosive in nature. Higher pH values suggest that CO2, carbonate-bicarbonate equilibrium is affected more due to change in physicochemical condition (Kamath and Godbole, 1987). According to WHO (1984), desirable pH of drinking water should be between 7 to 8.5. The analysis of variance indicated that pH of RO water samples differed significantly (p<0.05) from that of tap water, bottled water, sachet water (Table 1b) whereas that of national and local brands of packaged water samples did not differ significantly (p> 0.05) (Table 1c).
Table 1b: Comparison of different sources of drinking water with respect to physico-chemical and microbiological parameters
|Parameter||Source||Minimum||Maximum||Samples out of range (%)||Observed mean||SE±||P value||Significance|
|Bottled water||0||600||46.67||(SPClog10) 1.17||0.15|
Table 1c: Physico-Chemical and Microbiological Values of Packaged Water (Local and National Brands) (Mean± SE)
|Parameters||Source||Minimum||Maximum||Samples out of range (%)||Observed mean||SE±||P value||significance|
|pH||National Brand||7.1||8||none||7.46||0.1||0.206||Non significant|
|TDS ppm||National Brand||20||91||None||58||6.07||0.018||Significant P<0.05|
|SPC cfu/ml||National Brand||0||160||none||(SPClog10)0.91||0.19||0.057||Non significant|
|National Brand||0||0||none||0||0||Non significant|
Also no significant variation was observed between the pH of household drinking water samples, public water samples and packaged water ((p> 0.05) (Table 1a).
Table1a: Observed mean, P value and significance of physico-chemical and microbiological parameters of drinking water (Household Water (HHW), Public Place Water (PPW) and Packaged Water (PW), n=60 each)
|Parameter||Minimum||Maximum||Samples out of range (%)||Observed mean||SE±||P value||Significance|
The findings of this study agree with those of Narsimha et al. (2011) and Vyas et al. (2015), who reported the pH range in drinking water to be 6.4-8.4 and 7.5-8.7, respectively. Several other workers have observed normal pH values in drinking water all over the world (Ezeribe et al., 2012; Rehmanian et al., 2015; Tsega et al., 2013; Dorairaju et al., 2012; Sarwar et al., 2004). A pH of more than 8.5 in 6 of 100 water samples was reported by Kerketta et al. (2013). The results for pH values of packaged water in this study were almost similar to those of Singla et al. (2014), who reported pH of bottled water to be within 6.45-7.24.
Water being a universal solvent, can dissolve a wide range of inorganic and some organic minerals or salts such as potassium, calcium, sodium, bicarbonates, chlorides, magnesium, sulfates which constitute TDS (Trivedy and Goel, 1986). WHO desirable value of TDS in drinking water must not exceed 500 ppm (WHO, 1984) but is allowed upto 1500 ppm in unavoidable circumstances (Aulicino and Pastoni, 2004). We recorded high TDS values upto 2000 ppm with 65 (36.11%) samples exceeding the limit. School water samples had maximum TDS as children have to rely on handpump water to quench their thirst. Highly significant difference (p<0.01) was observed between the TDS values of water from household sources, public places and packaged water (Table 1a), (tap and school water samples), (RO, bottled and sachet water samples) and water from restaurants (p>0.01) (Table 1b) whereas difference was significant between the TDS values of national and local brands of packaged water (p<0.05) (Table 1c). In a study in Pakistan, TDS values of 780 water samples from 490 educational institutes in Karachi were found to be within 79-1066 ppm (Asadullah and Khan, 2013). Bhalla et al. (2014) found the TDS of packaged drinking water in Mathura to be within range. We found TDS range of national well known brands to be lesser than that of locally packaged water (Dodoo et al., 2006). TDS of natural water sources has been found to vary from 30-6000 ppm. It is considered a secondary drinking water standard as no direct effect is known to occur from drinking water with high TDS (Sailaja et al., 2015). Overall range of SPC in all the drinking water samples was within 0-105 cfu/ml with 53.33% (96/180) samples exceeding the WHO limit of < 100 cfu/ml. The analysis of variance indicated that SPClog10 values of water from household sources, public places and packaged water differed highly significantly (p<0.01). Also, variation was highly significant between (tapwater, RO, bottled, sachet and school water samples), and restaurant water (p<0.01) but non-significant between national and local brands of packaged water (p>0.05). Various studies confirm the presence of bacteria of public health importance in the drinking water (Sailaja et al., 2015; Baumgartner et al., 2006; Ezekiel et al., 2009). Our study clearly indicates that bottled water of national brands was much more hygienic than locally packaged or sachet water sold in streets, findings supported by various other studies (Gangil et al., 2013; Tahir, 2011; Osei et al., 2013; Adegoke et al., 2012; Kalpana et al., 2012; Edema et al., 2011). However no bacteria were found in bottled water in Turkey (Damirel et al., 2011).
Graph 1a: Physico-chemical and bacteriological parameters of household water (HHW), public place water (PPW) and packaged water (PW) (pH and SPC)
Graph 1b: Physico-chemical and bacteriological parameters of household water (HHW), public place water (PPW) and packaged water (PW) (TDS and coliforms)
Graph 2a: Physico-chemical and microbiological parameters of different sources of drinking water (TDS, MPN)
Graph 2b: Physico-chemical and microbiological parameters of different sources of drinking water (pH, SPC)
Graph 3: Comparison of physico-chemical and microbiological parameters of local and national brands of packaged water
A wide range of coliform count was observed (0->1800 coliforms/100ml) with 53.89% (97/180) samples exceeding the WHO range of 0 coliforms/100ml for treated water. MPN values of water from household sources, public places and packaged water differed highly significantly (p<0.01) (Table 1a). The values also differed highly significantly between (RO, bottled and sachet and school water samples) and (tap water and restaurant water samples) (p<0.01) (Table 1b) whereas no significant difference was evident in the MPN values of national and local brands of packaged water (p>0.05) (Table 1c). We found 33.33% and 16.7% of sachet and bottled water samples having coliforms in Jaipur, whereas overall, 25% of all packaged waters had coliforms. Gangil et al. (2013) found 40% packaged water samples having high coliform counts with 100% local sachet water samples harbouring coliforms. Several similar studies from Nigeria have shown poor bacteriological quality of drinking water in the region (Ibeine et al., 2012; Anyim et al., 2013; Godwill et al., 2015). All the Norwegian bottled water brands and imported brands of bottled water in Fiji were free from enteric indicator organisms (Zeenat et al., 2009; Otterholt and Charnock, 2011) whereas 5.3% and 10.2% of carbonated and noncarbonated mineral water samples in Hungary were positive for atleast one of the indicators of pathogenic bacteria (Verga, 2011). We recorded 80% of tap water samples to be out of range for coliforms. In Dhaka, Bangladesh, all the household water was heavily contaminated with coliforms, faecal coliforms and E. coli (Parween et al., 2008). In Pakistan also, 80% of drinking water samples from Khyber Agency had fecal coliforms (Ali et al., 2011).Studies in Andhra and Nepal have shown the exceedingly poor quality of municipal drinking water samples with respect to presence of coliforms (Sailaja et al., 2015; Prasai et al., 2007; Diwakar et al., 2008). Another study in Mathura reported 70% tap water, 95% of stored water and 40% of packaged water to be positive for coliforms (Jain et al., 2012). In a study by Sharma et al. (2017), out of 60 ground water samples, 16 E. coli were isolated. In same study, high values of TDS (upto 9000ppm), SPC (upto 3500 cfu/ml) and coliforms were found in 40% samples. Most of the school water samples had coliforms in Faislabad, Pakistan (Ilyas et al., 2008). In accordance, we found 73.3% (22/30) samples of school water exceeding the coliform limits thus exposing school children to various diseases. Suthar et al. (2009) reported coliform contamination in some rural habitations of northern Rajasthan. A linear correlation between TVC and coliforms has been shown by Jeena et al. (2006) thus higher SPC value might indicate presence of coliforms. Thus widespread fecal contamination of drinking water as well as of packaged water is evident from so many reports from all over the world emphasizing the need of awareness and strict monitoring of water quality standards at all levels.
The greatest risk to public health from microbes in water is associated with it being contaminated with human and animal excreta (WHO, 2011). A total of 19 E. coli were found in 180 (10.56%) drinking water samples with highest prevalence in water from public places (21.67 %) followed by household drinking water (10%). Among public sources, restaurants water samples had 30% E. coli followed by recovery of 13.33% E. coli from drinking water available to children in schools. Ramteke and Tiwari (2007) recorded a prevalence of 30.3% thermo tolerant E. coli in drinking water sources, much higher than that recorded in the current study. Prevalence of E. coliin Yamuna water was found to be 37.33% in a study by Singh et al. (2017). Many workers from all over India have reported E. coli in drinking water samples (Antony and Renuga, 2012; Suthar et al., 2009) suggesting gross faecal contamination of drinking water which has grave health implications as there are several highly adapted E. coli clones that have acquired specific virulence factors, which increase their adaptability to new niches, enabling them to cause diseases in healthy humans and animals (Kaper et al., 2004). Severe water borne outbreaks implicating Verotoxic E. coli (VTEC) have been reported even from developed countries like Canada (Hrudey et al., 2003) and NewYork (Bopp et al., 2003). In 1982, a rare serotype E. coli 0157:H7 was isolated from patients with bloody diarrhea in USA (Karmali et al., 1983).
None of the packaged water samples had E. coli (Table 2), similar to the findings in Chennai (Venkatesan et al., 2014) and Nigeria (Sunday et al., 2011; Umaru et al., 2015) However, Singh, (2011) isolated 1 E. coli from 20 packaged water samples from Mathura and in Jaipur city, 40% of sachet water had E. coli, indicating the faecal contamination of packaged water (Gangil et al., 2013). The findings of this study clearly indicate the sorry state of available drinking water quality. Except RO and packaged water, none of the water samples were suitable for consumption. The situation is worse in case of water available for drinking at public places like restaurants and schools. Children are made to consume unsafe water, risking their health and life.
Table 2: Isolation of E. coli
|S. No.||Source||No. of Samples||Percent Positivity of E. coli (%)|
|Drinking Water||180||19 (10.56)|
|i||Household Water (HHW)||60||6 (10)|
|a. Tapwater||30||6 (2)|
|b. RO water||30||0|
|ii||Public Place Water (PPW)||60||13 (21.67)|
|a. Restaurants||30||9 (30)|
|b. Schools||30||4 (13.33)|
|iii.||Public Packaged Water (PPW)||60||0|
|a. Bottled water||30||0|
|b. Sachet water||30||0|
Mathura being a major pilgrim center, attracting lakhs of tourists every year, creates stress on already shrinking water resources. Packaged water of poor quality freely available on the streets of Mathura, without any proper monitoring of quality standards, poses tremendous health risk to the consumers. This study is a step forward in highlighting the fact that present status of drinking water quality is far from satisfactory. Timely intervention might lead to remedial measures for improving the existing drinking water quality situation and more stringent steps to be taken to monitor the quality of packaged water, especially the local brands.
This work was a part of Ph.D thesis in the Department of Veterinary Public Health, College of Veterinary Science and Animal Husbandry, U.P. Pt. Deen Dayal Upadhyay Veterinary University, DUVASU, Mathura. The authors would like to thank Vice-Chancellor and Dean, Dean PG, DUVASU, Mathura for providing all the facilities necessary for the work.