Ceramic water filters coated with silver nanoparticles are effective at treating contaminated drinking water in rural communities. A study tested locally produced ceramic filters, one coated with silver nanoparticles and one not coated, on microbial pathogens in water from a stream in Iwo, Nigeria. Results showed that both filters removed 100% of tested pathogens like Salmonella, E. coli, and parasites after filtration. Physicochemical properties of the water like turbidity, conductivity and coliform levels also saw over 90% reductions on average with both filter types during the 240 minute testing period. The silver nanoparticle coated filter performed slightly better at removing contaminants. Therefore, locally produced ceramic filters, especially when coated with silver, can provide a low-cost way

1. Efficacy of Ceramic Filter Coated with
Silver Nanoparticles for Drinking Water
Treatment
Aromolaran, O., Nwobosi, C.V., Adeniji, A.F. and Ayansina, A.D.V.
Department of Biological Sciences
Bowen University, Iwo,
Nigeria

2. Introduction
• Over 2.6 billion people lack access to clean water, which is
responsible for about 2.2 million death annually of which 64% are
children (WHO 2010).
• Each year 3.4 million people die from water related illness such as
diarrhea, dysentery, typhoid fever etc. (WHO,2014).
• Four thousand children die each day as a result of contaminated
water (UNICEF, 2014).
• Many people especially in the rural areas depend on surface water
as their main water supply and this water source is highly
contaminated.
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3. • Many people in these rural communities
would have to fetch water away from
homes and store in household (Brown and
Sobsey, 2010).
• Contamination could also occur during
collection, transport and storage which
could increase the chances of water-borne
infections.
• Conventional treatment of water can be
capital intensive and far fetching (Sobsey
2002).
• Point of use (POU) method of water
purification could provides a better option
(Clasen et al., 2004; Oyanedel-Craver and
Smith, 2008)
Plate 1: Source of water supply
to a rural community
Source: waterjournalistafrica.com
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4. Plate 2: Mechanism of microbial removal by CWF
Source: Sullivan et al., 2017
Ceramic water filter Porous ceramic matrix Contaminant removal
(size exclusion)
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The Guatemala Research and Potters for Peace (PfP)
*Ceramic water filter (CWF) is produced from fine clay+saw dust/rice husk+water.

5. Bacteriocidal effect of ceramic water filter (CWF)
coated with silver nanoparticles (AgNPs)
Plate 3: Mechanism of interaction between AgNPs and bacteria cells
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6. • Justification of Research
 Although, ceramic water filter (CWF) has been in use for a
long time worldwide and is very effective with low cost, the
knowledge of the microbial effectiveness of locally produced
CWF in Nigeria is limited.
• Objective of study
 To evaluate the effectiveness of two porous ceramic filters
(one coated with AgNPs and the other without AgNPs) against
microbial pathogens in drinking water in a rural community in
Iwo.
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7. Methodology
• Study area and sample collection (map of the study area)
• Ceramic water filter from Atomora pottery (purchase from where,
the process and the composition)
• Quality control – sterilization and flow rate test what is the flow rate?
• Synthesis and application of AgNPs (Lantagne and Greywood, 2001;
Misha et al., 2018)
• Physicochemical and microbial analyses of water sample (APHA,
1998)
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8. Results
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9. S/N Microorganisms Raw stream
sample
Filtered stream
sample
1 Salmonella sp. + -
2 Serratia sp. + -
3 Proteus sp. + -
4 Citrobacter sp. + -
5 Enterobacter sp. + -
6 Klebsiella pneumoniae + -
7 Escherichia coli + -
8 Staphylococcus aureus + -
9 Shigella dysentriae + -
10 Pseudomonas sp. + -
11 Amoeba histolytica + -
Table 1: Presence of microorganisms in water sample
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10. Time
(minutes)
pH Turbidity
(520 nm)
Electrical
conductivity
(µS/m)
Nitrate
(mg/L)
Total
Hardness
(mg/L)
0 7.80 0.20 97.80 0.011 420
30 7.80 0.04 54.20 0.026 315
60 7.90 0.02 52.30 0.008 246
90 7.20 0.02 48.50 0.028 200
120 7.30 0.01 48.80 0.003 268
150 7.50 0.04 46.30 0.019 450
180 7.20 0.01 47.90 0.008 248
210 7.40 0.04 33.80 0.016 274
240 7.40 0.02 27.00 0.012 375
Table 2: Physicochemical properties of Onilete stream during filtration
with ceramic water filter coated with nanoparticles
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• WHO permissible limit in drinking water: pH – 7.5-8.5; Turbidity ; Electrical conductivity ;
nitrate; Total hardness

11. 0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
Pb Cu Zn Cd Fe
Concentration
(mg/L)
Heavy metals
Raw stream sample
Filtered stream sample
WHO*
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Fig. 2: Presence of heavy metals in Onilete stream sample and filtered
sample

12. 6.6
6.8
7
7.2
7.4
7.6
7.8
8
8.2
8.4
0 30 60 90 120 150 180 210 240
pH
Time of filtration (minutes)
CF
CFNP
CF – 2.46% ↑
CFNP – 5.13% ↓
Figure 3: pH of Onilete stream samples during filtration
CF - ceramic filter
CFNP - ceramic filter coated with silver nanoparticles
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13. 0
0.05
0.1
0.15
0.2
0.25
0.3
0 30 60 90 120 150 180 210 240
Absorbance
(520
nm)
Time of filtration (minutes)
CF
CFNP
CF – 92% ↓
CFNP – 90% ↓
Figure 4: Turbidity of Onilete stream samples during filtration
CF - ceramic filter
CFNP - ceramic filter coated with silver nanoparticles
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14. 0
20
40
60
80
100
120
0 30 60 90 120 150 180 210 240
Electrical
conductivity
(µS/m)
Time of filtration (minutes)
CF
CFNP
CF – 77.43% ↓
CFNP – 72.39% ↓
Figure 5: Electrical conductivity of Onilete stream samples during filtration
CF - ceramic filter
CFNP - ceramic filter coated with silver nanoparticles
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15. -200
0
200
400
600
800
1000
1200
1400
0 50 100 150 200 250
MPN*/mL
Time of filtration (minutes)
CF
CFNP
Figure 6: Coliform reduction in Onilete stream samples during filtration
CF - ceramic filter
CFNP - ceramic filter coated with silver nanoparticles
MPN* – Most probable number
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16. 0
20
40
60
80
100
120
0 30 60 90 120 150 180 210
Percentage
reduction
(%)
Time of filtration (minutes)
CF
CFNP
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Figure 7: Percentage reduction of coliforms in Onilete stream samples
during filtration
CF - ceramic filter
CFNP - ceramic filter coated with silver nanoparticles

17. Acknowledgements
• Management of Bowen University, Iwo Osun State
• The technical staff – Mrs. Akinola, Mrs Atobatele…..
• Dear colleagues
• Students
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18. for the attention
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