Economical solution to remove microbes from harvested roof water

Abstract

Scarcity of potable water is being experienced throughout the world due to increasing population (demand) and environmental pollution. These shortages are experienced more by poor rather than the rich, who can afford costly modern technologies for survival. Roof water harvesting is an ideal technique to collect and store water for drinking purposes. However, with time, in spite of all the precautions, there is a possibility of development of microbes in stored water that makes it unsafe for drinking. Moreover, microbe infected water is one of the major concern in most parts of developing countries. There are many water purification methods, although, most of them are expensive and beyond the reach of many people, especially in rural areas. In India, since ancient times, Ayurveda recommends use of copper pots / vessels for storing drinking- water, but, in last few decades, copper is replaced by steel, plastic and earthen pots. In conventional water distribution system chlorine is used to disinfect drinking water, but, it has several detrimental effects, so replacement of chlorine is essential. In this study an attempt was made to study the best method among the Copper, Silver treatment, earthen pot or Plastic jugs for removal of biological contamination from drinking water for domestic use. The result revealed that copper vessel showed maximum inhibitory effect on coliform as well as total bacterial count at 12 hrs and 24 hrs. There was a slight increase in pH and Copper concentration but it remains within the permissible limits laid by World Health Organization. The findings indicate that vessel or pot made up of copper could be used for antimicrobial treatment for purification of drinking water. It would be very economical solution to disinfect potable water, without any energy requirements, which could be adopted in urban / rural areas of the developing countries.

Full text

Eco. Env. & Cons. 20 (Suppl.) : 2014; pp. (S143-S148)
Copyright@ EM International
ISSN 0971–765X
*Corresponding author’s email: pksnvs@nau.in
Economical solution to remove microbes from
harvested roof water
Darshana Patel, P.K. Shrivastava* and D.P. Patel
Department of Natural Resource Management, ASPEE College of Horticulture & Forestry,
Navsari Agricultural University, Navsari 396 450, Gujarat, India
(Received 10 June 2014; accepted 21 July, 2014)
ABSTRACT
Scarcity of potable water is being experienced throughout the world due to increasing population (demand)
and environmental pollution. These shortages are experienced more by poor rather than the rich, who can
afford costly modern technologies for survival. Roof water harvesting is an ideal technique to collect and
store water for drinking purposes. However, with time, in spite of all the precautions, there is a possibility
of development of microbes in stored water that makes it unsafe for drinking. Moreover, microbe infected
water is one of the major concern in most parts of developing countries. There are many water purification
methods, although, most of them are expensive and beyond the reach of many people, especially in rural
areas. In India, since ancient times, Ayurveda recommends use of copper pots / vessels for storing drinking-
water, but, in last few decades, copper is replaced by steel, plastic and earthen pots. In conventional water
distribution system chlorine is used to disinfect drinking water, but, it has several detrimental effects, so
replacement of chlorine is essential. In this study an attempt was made to study the best method among the
Copper, Silver treatment, earthen pot or Plastic jugs for removal of biological contamination from drinking
water for domestic use. The result revealed that copper vessel showed maximum inhibitory effect on coliform
as well as total bacterial count at 12 hrs and 24 hrs. There was a slight increase in pH and Copper concentration
but it remains within the permissible limits laid by World Health Organization. The findings indicate that
vessel or pot made up of copper could be used for antimicrobial treatment for purification of drinking
water. It would be very economical solution to disinfect potable water, without any energy requirements,
which could be adopted in urban / rural areas of the developing countries.
Key words: Harvested roof water, Water purification, Copper vessel, Drinking water
Introduction
Water is the vital component of all living organisms,
besides it is the primary source to cause the disease
like diarrhea‚ typhoid and various other diseases to
the human being. The major danger associated with
drinking water is its possibility of contamination by
sewage, decay of plant, animal and human waste.
Microbial decay of organic material leads to multi-
plication of host of pathogens that mix with water
which acts as a carrier of bacteria causing infectious
disease as enteric fever or dysentery. Potable use of
such water leads to infections and disease. Provid-
ing safe drinking water to the majority of the
world’s population especially to those in developing
countries‚ is still a major problem. According to the
World Health Organization, an estimated 4.1% of
the total global burden of disease is contributed by
diarrhea illness: around 88% of that burden is due to
unsafe water supply, sanitation and hygiene, with
children in developing countries being the most
common victims (WHO, Burden of disease and cost

S144 Eco. Env. & Cons. 20 (Suppl.) : 2014
effectiveness estimates, 2004). Escherichia coli
(ETEC), rotavirus, Vibrio cholera, and species of Shi-
gella, spreads through contaminated water and food
or from person to person (Qadri et al., 2005). In In-
dia, many states still have outbreaks of cholera.
During 1996-2007, at least 2,22,038 individuals were
affected by cholera (Kanugo et al., 2010). In develop-
ing countries the public water distribution system
are often poorly maintained. moreover‚ treated wa-
ter is also often observed to be re-contaminated be-
cause of unsafe storage and handling practices
within household (Mintz et al., 2001); thus‚ it is im-
portant to explore effective strategies and ap-
proaches that are affordable‚ simple, maintenance
free and that which can be implemented at home
and are acceptable to the population. Storing water
in gold‚ silver and copper pots finds mention in an-
cient texts of Ayurveda for purification of water
(Sharma, 2004). In recent years, this practice has
been replaced by the use of earthen pot‚ steel and
plastic containers as gold‚ silver and copper are ex-
pensive.
The antimicrobial effect of copper and copper al-
loys on pathogens such as Escherichia coli (Sharan et
al., 2010, Dhanalakshmi and Rajendran, 2013)‚ Sal-
monella, Shigella (Dhanalakshmi and Rajendran,
2013)‚ Methicillin-resistant Staphylococcus aureus
(MRSA) (Niiyama et al. 2013), Mycobacterium tuber-
culosis (Copper Development Center, 2004;
Godbole, 1971), Influenza A virus (Noyce, 2007)and
Salmonella typhi and Vibrio cholera (Kanugo et al.
2010) has been reported. Copper’s antimicrobial
properties have been recognized and applied by
many ancient cultures for disease control and water
treatment. (Borkow and Gabbay, 2005; Gorman and
Humphreys, 2012). Copper is an essential micronu-
trient for plant, animal and human health (Interna-
tional Copper Association, 2012. Copper Develop-
ment Association, 1988) but rarely occurs naturally
in drinking water. Human body requires copper in
very small amount, its higher concentration in
drinking water can cause health hazard. Elevated
levels of copper for 14 days or more can cause per-
manent kidney and liver damage in infants under
the age of one year and can cause nausea‚ vomiting
and diarrhea and stomach cramps in people of all
ages (David, 2003). Very high level copper can cause
a bitter metallic taste in water and result in blue-
green stains on water surface (Healthy drinking
waters for rhode islanders, 2003).
Materials and Method
Due to shortage of good quality drinking water in
Navsari Agricultural University campus, roof water
harvesting was taken up in several buildings of the
University. Storage tank were designed to meet the
demands of the people using the building. Though,
chemical water quality of all storage tanks was
found to be below 50 TDS during four year of moni-
toring. However, it was found that in spite of adopt-
ing all precautions; there remains the possibility of
development of microbes in stored water, so this
study was planned to remove microbes before con-
suming the water.
Collection of sample for treatment
The harvested roof water during monsoon was col-
lected from a building where the residents did not
follow the recommended measures of storage, mak-
ing it vulnerable for development of microbes. Wa-
ter was collected in a big sterilized 50 liter capacity
plastic container. Initial water sample showed 50 to
130 total coliform (MPN/100 mL) and 3.5x 103 to
5.3x 103 total bacterial count, that tank was kept for
24 hrs at room temperature, later, five replications
were prepared.
Treatment and control
Five liter water was kept in five different vessels /
pots, the treatments consisted of: T1= water stored
in a Copper vessel, T2 = Silver Treatment (Silver
strip of 30 cm x 10 cm x 0.03 cm size immersed in
container), T3= water passed through commercially
available cloth filter, T4= water stored in an Earthen
pot and T5= Control. These storage vessels were
thoroughly cleaned each time before use with 70 %
alcohol, sterile distilled water and surface sterilized
with UV light.
Microbiological analysis
Enumeration of bacterial growth
All pots were incubated at room temperature (20-25
oC) up to 24 hrs. Samples were collected after every
0 hrs‚ 6 hrs‚12 hrs‚ 24 hrs in sterilized glass bottle
and analyzed immediately or at times stored in re-
frigerator to avoid multiplication during holding
time. The whole experiment was replicated four
times.
Samples were analyzed for total bacterial count

PATEL ET AL S145
(CFU/mL) and total coliform (MPN/100 mL). Total
bacterial count were determined by plating on Nu-
trient agar (Standard Plate Count) and incubated at
37μC for 24 hrs while multiple tube technique was
used for the enumeration of Most Probable Number
of total coliform bacteria by using standard method
i.e. presumptive coliform test‚ confirmatory test and
complete confirmation test (Bureau of Indian Stan-
dards 2012) Nutrient agar (NA) as a basal medium
and MacConkey agar as a differential medium were
used to determine enteric bacteria.
Detection of pH and Copper
pH was analyzed at 0 hr‚ 6 hrs‚12 hr and 24 hr by
using pH meter (Systronics make, μ pH system 362)
and Copper concentration was analyzed after every
2 hrs interval in T1 water samples till 60 hr by using
Atomic Absorption Spectrophotometer
Results
Laboratory study was conducted to find the copper
residue in water at different time’s periods of stor-
age. The collected water samples were tested before
and after different treatment at 6 hrs, 12 hrs and 24
hrs time intervals for reduction of total coliform
count by MPN test (Fig. 1) in lactose broth and on
the nutrient plate to measure the total bacterial
count (Fig. 2) as the colony forming unit. Table 1
and Table 2 show statistical analysis regarding re-
duction in total coliform (MPN/100 mL) and total
bacterial count (CFU/ml) in different treatment
with time, i.e. 6 hr, 12 hr and 24 hr. According to the
results, the treatment trend was found consistent
with the duration as interaction is Non Significant.
The pH in all treatment sample and level of cop-
per in T1 (Figure 3) leached in to the test sample, but
it remained within the WHO permissible limit set
by WHO [ pH<8.5 and 1.3 mg/L of copper] the
(WHO. Guideline for Drinking water Quality, 1993),
even when drinking water is stored till 4 to 5 days.
Discussion
The major public health problems in many develop-
ing countries are the enteric fever and cholera by the
global initiatives in water and sanitation (Ochiai et
al., 2005; Gaffga et al., 2007), prior most due to lack
of adequate sanitation facilities and awareness for
safe drinking water, alongside issues related to per-
sonal hygiene (Araya et al., 2004). The contamina-
tion occurs during the transport and /or storage at
the household level (Espirito Santo et al., 2011). As
it’s a known fact that during ancient time copper
pots were used for storage of drinking water and
many experiments proved the copper has antimi-
crobial activity mainly on the water borne patho-
gens (Noyce et al., 2007; Preethi Sudhaa et al., 2009,
Sharan et al., 2011).
The oligodynamic effect a toxic effect of metal
ions on living cells, algae, molds, spores, fungi,
viruses, prokaryotic and eukaryotic microorgani-
sms, even in relatively low concentrations. Several
metal ions, especially heavy metals, show this effect
Fig. 2. %Reduction in CFU with time in different
Treatment
Fig. 1. %Reduction in MPN with time in different
Treatment
Fig. 3. Copper residue in water stored in copper pot for
eight days

S146 Eco. Env. & Cons. 20 (Suppl.) : 2014
Table 1. ANOVA RBD-% reduction in MPN with time
Treatment 6 hr 12hr. 24 hr pooled
T1=Copper Treatment 66.86 85.18 89.57 80.54
T2=Silver treatment 56.44 81.54 87.64 75.21
T3=Filtration 47.18 63.36 65.64 58.73
T4=Earthen pot 52.35 64.94 72.94 63.41
T5=Control 41.23 58.36 55.84 51.81
SEM 2.12 2.7 1.76 2.04
CD 6.53 8.32 5.44 3.96
Time 52.81
h1 ---
h2 - - - 70.68
h3 - - - 74.33
SEM - - - 6.24
CD - - - 17.64
Interaction(T x H)
SEM - - - 2.22
CD - - - 6.39
CV% 8.04 7.64 4.75 6.76
Table 2. ANOVA RBD- % reduction in Total Bacterial Count with time
Treatment 6 hr 12hr. 24 hr pooled
T1= Copper Treatment 48.64 66.94 80.74 65.44
T2= Silver treatment 40.51 60.05 75.69 58.75
T3= Filtration 36.08 47.5 60.65 48.08
T4= Earthen pot 39.28 53.25 63.16 51.9
T5 =Control 13.49 34.09 44.8 30.79
SEM 3.12 1.63 1.95 1.39
CD 9.61 5.03 6.03 3.96
Time
h1 (6 hr) - - - 35.6
h2 (12 hr) - - - 52.37
h3 (24hr) - - - 65.01
SEM - - - 6.24
CD - - - 17.64
Interaction(T x H)
SEM - - - 2.32
CD ---NS
CV% 17.54 6.24 6.02 9.13
to various degrees. Bacteria are in general affected
by the oligodynamic effect. Viruses in general are
not very sensitive to this effect, since viruses are not
considered to be metabolically active outside
their host range. Certain metals, such as silver,
copper and copper alloys, are known to be far more
poisonous to bacteria than others, such as stainless
steel and aluminum. Silver is capable of rendering
stored drinking water potable for several months.
Water of Low pH or acid rain water when col-
lected in Copper vessel for domestic consumption
can cause poisoning in humans. The U.S. Environ-
mental Protection Agency’s Maximum Contami-
nant Level (MCL) in drinking water is 1.3 milli-
grams per liter. The MCL for copper is based on the
expectation that a lifetime of consuming copper in
water at this level is without adverse effect (gas-
trointestinal). Copperiedus can occur from eating
acid foods cooked in uncoated copper cookware or
from exposure to excess copper in drinking water or
other environmental sources.
Copper treatment was best followed by water
treated with silver strip, while cloth filtration and
earthen pot are less effective for reduction of bio-

PATEL ET AL S147
logical contamination (total coliform and total bac-
terial count).
The result of copper treatment at 6 hr, 12 hr and
24 shows reduction in total coliform by 67%, 85%
and 90% as well as total bacterial count by 49%, 67%
and 81%, respectively. While, in Silver treatment, re-
duction in total coliform was 56%, 82% and 88% and
total bacterial count by 41%, 60% and 76% respec-
tively. In Filtration treatment, reduction in total
coliform 47%, 63% and 65% and total bacterial count
by 36%, 48% and 61% respectively. In Earthen pot
reduction in total coliform 52%, 65% and 73% and
reduction in total bacterial count by 39%, 53% and
63% respectively.
As per the statistical analysis after 6 hr incubation
Copper treatment (T1) was best treatment flowed
by Silver Treatment (T2) and Earthen pot (T4), T4
was at par, but better than Filtration (T3) and Con-
trol (T5). Whereas, after 12 hrs of incubation, Cop-
per treatment (T1) and Silver Treatment (T2) are at
par, but better than Filtration (T3), Earthen pot (T4)
and Control (T5). After 24 hr incubation, Copper
treatment (T1) was the best method than Silver
Treatment (T2) and Filtration (T3), Earthen pot (T4)
and Control (T5) were at par for removal of bacterial
contamination from drinking water. Filtration (T3)
Earthen pot (T4) and Control (T5) were found to be
less effective in removal of bacterial contamination
from water. Silver Treatment (T2) was also effective
but use of silver become too costly so among all of
these treatment the best as well as cost effective
method was the Copper treatment (T1)
Studies have shown the merits of copper surfaces
for their use in improving public hygiene in
healthcare facilities, the potential use of copper for
the purification of drinking-water, especially in de-
veloping countries, has not been widely studied.
Therefore, results of our study indicate that copper
holds potential to provide microbial-safe drinking-
water to the rural areas in developing countries. The
use of copper pots in Indian households is common
therefore, likely to be socially accepted by the
people. Its functioning is not dependent on fuel,
electricity, replaceable filters, intensity of sunlight,
etc. to operate or maintain it; it is simply a passive
storage of water. This takes into account the condi-
tions prevailing in rural villages and the urban
slums of developing countries. The health benefit
that can be achieved by using copper pot as water-
purification device will far outweigh the cost of the
pot, if divided over the members in a rural family,
especially when it will be a one-time investment
with no recurring costs.
Conclusion
To disinfect harvested rain water for drinking pur-
pose, against any microbial activity, water could be
safely stored in a copper vessel for 12 hr and 24 h to
reduce Coli-form by 85% and 90% and total bacte-
rial count by 67% and 81 % respectively.
References
Araya, M., Olivares, M., Pizarro, F., Llanos, A., Figueroa,
G. and Uauy, R. 2004. Community-based random-
ized double-blind study of gastrointestinal effects
and copper exposure in drinking water. Env Hea
Pers. 112: 1068-1073.
Borkow, G. and Gabbay, J. 2005. Copper as a Biocidal Tool.
Current Medicinal Chemistry, 12(18) : 2163-2175.
Bureau of Indian Standards. May 2012. Methods for bac-
teriological examination of drinking water, New
Delhi,
Copper Development Association. 1988. Copper in Plant,
Animal and Human Nutrition. CDA publication
TN35. Retrieved from: http://www.pdfpedia.com/
download/6128/copper-in-plant-animal-and-hu-
man-nutrition-pdf.html
Copper development center. 2004.http://www.copper.
org.sg/publications/cca/03 09/pg06_japan_
research.html
David, E., Kissel‚ Paul F. Vendrell and Jorge H. Atiles. 2003.
Your household water quality: lead and copper. The
university of Georgia cooperative extension service‚
household water quality series 10
Dhanalakshmi, T. and Rajendran, S. 2013. Antimicrobial
Activity of Micro Sized Copper Particles On Water
Borne Bacterial Pathogens. International Journal of
Scientific and Technology Research. 2(1) : 115-118
Espirito, S.C., Lam, E.W., Elowsky, C.G., Quaranta, D.,
Domaille, D.W., Chang, C.J. et al. 2011. Bacterial kill-
ing by dry metallic surfaces. App Environ Microbiol.
77 : 794-802.
Gaffga, N.H., Tauxe, R.V., Mintz, E.D. 2007. Cholera: A
new homeland in Africa, Am J Trop Med Hyg. 77 :
705-713
Godbole, S.H. 1971. An effective and simple method for
disinfection of water. Indian J Med Sci. 25 : 712-718.
Gorman, J.O. and Humphreys, H. 2012. Application of
copper to prevent and control infection. Where are
we now? Journal of Hospital Infection. 81 (4) : 217–223.
Healthy drinking waters for Rhode islanders. Private wells
series, April 2003. State of Rhode island. Department
of health and the university of Rhode island coop-
erative extension department of natural resource
Science.

S148 Eco. Env. & Cons. 20 (Suppl.) : 2014
International Copper Association. 2012. Copper Facts.
Retrieved from: http://copperalliance.org/history-
of-copper/#sthash.jPI4EbsG.dpuf
Kanugo, S., Sah, B.K., Lopez, A.L., Sung, J.S., Paisly, A.M.
and Sur, D. et al. 2010. Cholera in India: an analysis
of reports, 1997- 2006. Bull World Health Orgaization
88 : 185-191.
Mintz, E.‚ Bartram, J.‚ Lochery, P. and Wegelin, M. 2001.
Not just a drop in bucket: expanding access to point-
of use water system. Am J public health. 91 : 1565-1570.
Noyce, J.O., Michels, H. and Keevil, C.W. 2007. Inactiva-
tion of influenza A virus on copper versus stainless
steel surfaces. App Environ Microbiology. 73 : 2748-
2750.
Ochiai, R.L., Wang, X.Y., Von, S.L., Yang, J., Bhutta, Z.A.,
Bhattacharya, S.K., Agtini, M., Deen, J.L., Wain, J.,
Kim, D.R., Ali, M., Acosta, C.J., Jodar, L. and
Clemens, J.D. 2005. Salmonella Paratyphi A rates,
Asia. Emerg Infect Dis. 11 : 1764-1766.
Preethi Sudhaa, V.B., Ojit Singha, K., Prasad, S.R. and
Venkatasubramaniana, P. 2009. Killing of enteric
bacteria in drinking water, by a copper device for
use in the home: laboratory evidence. Trans. of the
Royal Soc. of Tropi. Medi.e and Hy. 103 : 819-822.
Qadri, F., Svennerholm, A.M., Faruque, A.S. and Sack, R.B.
2005. Enterotoxigenic Escherichia coli in developing
countries: epidemiology, microbiology, clinical fea-
tures, treatment, and prevention. Clin Microbiol Rev.
18 : 465-483
Sharma, P.V. editor. 2004. Susruta Samhita. Vol 1, Sutra
Sthana 45, 246 Verse 13, 418 Varanasi: Chaukamba
Visva Bharati.
Sharan, R., Chhhibber, S., Attri, S. and Reed, R.H. 2010.
Inactivation and injury of Echerichia coli in a copper
water storage vessel: effect of temperature and pH.
Antonie Van Leeuwenhoek. 97 : 91-97.
Sharan, R., Chhibber, S. and Robert, H. Reed. 2011. Inacti-
vation and sub-lethal injury of salmonella typhi,
salmonella typhimurium and vibrio cholera in cop-
per water storage vessels. BMC Infectious Diseases. 11:
204.
http://www.biomedcentral.com/1471-2334/11/204.
WHO: Burden of disease and cost effectiveness estimates.
204. (http:/www.who.iny/water-sanitatiohealth/
diseases/burden/en/index.html)
WHO. Guideline for Drinking Water Quality. 2nd ed. 1993.
Geneva : World Health Organozation.
Niiyama, N. et al. May 2013. Use of copper alloy for pre-
venting transmission of methicillin-resistsnt staphylo-
coccus aureus contamination in the dermatology
ward. Acta derm venereal. Doi: 10. 2340/00015555-
1472, 93(3): 294-300.