Microbiological Assessment of Marketed Drinking Water in Gaza City
Date
2009-06-20
Authors
Shady Al Tartory
شادي الترتوري
Journal Title
Journal ISSN
Volume Title
Publisher
Al-Quds University
Abstract
Water shortage is becoming one of the most important problem in the world today,
specially in area as Gaza strip where it suffered from severe shortage. The microbiological
quality of water in Gaza strip is so poor. So, to this reason we performed this study that
aimed to investigate the microbiological quality of the different types of marketed drinking
water in the Gaza city. The study population consisted of 20 samples collected from
desalination plants, 12 samples from water distribution cars, 25 samples from vending
machines, and 12 samples from bottled water that manufactured in the Gaza city. An
experimental design was used to verify water microbiological quality using Membrane
Filtration Technique (sterile nitrocellulose acetate membrane filters) placed on
MacConkey, cetrimide, and Doxi's media for isolation and detection of both total and fecal
coliforms, Pseudomonas aeruginosa, and fungi (mold and yeast) respectively.
The results of water samples that collected from desalination plants showed that 12
samples (60%) out of 20 samples were contaminated with total coliforms (1-50 cfu/100ml
). 50% of samples that collected from distribution cars (6 out of 12) were found to be
contaminated with total coliforms in a level of (1-20 cfu/100ml.) The water samples that
collected from vending machines also showed a high percentage contamination as in the
desalination plants where 15 samples out of 25 (60%) were found to be contaminated with
total coliforms in a range of (1-50 cfu/100ml).
Regarding the presence of fecal coliform in the different water samples, we found 6
samples out of 20 from the desalination plants (30%) were contaminated with fecal
coliforms in a range of (1-30 cfu/100ml); 5 samples out of 12 (41.7%) in the water
collected from distribution cars in a range of (1-10 cfu/100ml); and 4 samples out of 25
(16%) in the water collected from vending machines.
Regarding the presence of Pseudomonas aeruginosa in the tested samples, 45% (9 out of
20) of samples that collected from desalination plants were found to be contaminated in the
level of (1- 200 cfu/250ml). However, a 50% (6 out of 12) of samples in water collected
from distribution cars were found to be contaminated in the level of (1-20 cfu/250ml ). The
vending machines showed 48% (12 out of 25) contamination with P. aeruginosa in a
range of (1-65 cfu/250ml).
The presence of fungi including both yeast and molds were estimated. In the desalination
plants, 25% (5 out 20) and 20% (4 out of 20) samples were contaminated with molds (1-
10 cfu/100 ml) and yeast (1-50 cfu/100 ml) respectively; 10 samples (83.3%) and 6
samples (50%) out of 12 were contaminated with molds (1-15cfu/100ml) and yeast (1-20
cfu/100ml) respectively in water samples collected from distribution cars. Finally in the
vending machines, we found that 14 samples (56%) and 4 samples (16%) out of 25 were
contaminated with molds (1-20 cfu/100ml) and yeast (1-20 cfu/100ml) respectively.
Finally the results of water samples collected from bottled water showed that all samples
were free from Total and Fecal coliform bacteria . For total bacterial count the results
showed that 4 samples (33%) out of 12 samples were contaminated with bacteria ( > 100
cfu /1 ml ) , Meanwhile P. aeruginosa were found at 2 samples (16.6%) out of 12 samples
and finally no Yeast or Molds were found in bottled water sample