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Journal of Evolutionary Biology Research Vol. 2 (1), pp. 7-14, December 2010 Available online at http://www.academicjournals.org/jebr ISSN 2141-6583 2010 Academic Journals Ful Length Research Paper The effect of magnetic field on the physical, chemical
and microbiological properties of the lake water in
Saudi Arabia
Molouk Mohammed Khazan Alkhazan1 and Amna Ali Nasser Saddiq2*
1Department of Botany, Faculty of Education, King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia. 2Department of Microbiology, Faculty of Education, King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia. Accepted 9 November, 2010 The present study aims at solving the problem of stagnant water due to receiving of sewage water in a
lake at Eastern Jeddah, using state of the art safe techniques. Samples were collected from the lake,
then treated using magnetic fields with different intensities in two states, static and shaking, for 30
days. Hence, the physical and chemical properties for samples were measured, in addition to their
bacterial content. In both cases of static and shaking, increasing the magnetic flux density caused
water clearness, in addition to a relative increase in the pH value and a remarkable decrease in its odor
and electric conductivity (EC). In addition, it was observed that lead ions and bacterial content
decreased. The study shows that the increasing magnetic field intensity to the level used in this study,
accompanied by shacking, is supplemented with the findings of the experiment. It also suggests that
the magnetic field plays a major role in finding successful solutions for a lot of environmental
problems, as the strong bonds that connect man to nature should be avoided.

Key words: Magnetic field, stagnant water, electric conductivity, pH, bacteria.

INTRODUCTION
Water pol ution is regarded as one of the most critical after treatment with chlorine and ozone. Using Ozone has environmental problems, as it causes change in water no side effects, however, some disadvantages were color and increase in microscopic harmful living discovered, like the short life-time of its effect and organisms count, which causes the spread of dangerous needing water pretreatment for removing high epidermal diseases, The water pol utants can be concentration of organic substances and algae. As a eliminated by physical methods like filtration, as wel as result, new efficient and safe methods were needed. chemical treatments like chlorination which is one of the Thus, a biological technique using the magnetic field to most widely used disinfectants (Vesilind et al., 1990), purify water was introduced. This technique is considered although chlorine does treat water from change of odor as a simple simulation of what happens in nature, as and color, hydrogen sulphide, growth of algae, germs; when water is subjected to a magnetic field and as a however, its addition resulted in the appearance of result, becomes more biological y active. increased resistance of bacteria to biological antibiotics The phenomenon of water treatment with an applied such as ampicil in, streptomycin and sulphagolanamy (El- magnetic field has been known for many years and has Zanfaly, 1991). Ozone also is used as a disinfectant in been reported as being effective in numerous instances water treatment, as it oxidizes the organic blemishes, (Kronenberg et al., 1985; Lin et al., 1990 and Balcavage removes color, odor and taste problems and is a fast et al., 1996). Magnetism sciences has developed and bacteria eradicator. become more complicated, when its properties were Nieminski and Bradford (1991) found that, water found to have linkage with al solid, liquid and gaseous bacterial content decreased by 85 and 98.8%, respectively, matters in addition to living organisms. Johan-Sohaili et al. (2004) explained that, magnetic technology is a promising treatment process that can enhance the separation of suspended particles from the sewage. Tai *Corresponding author. E-mail: [email protected]. et al. (2008) observed that on subjecting water to magnetic 8 J. Evol. Biol. Res. field, it leads to modification of its properties, as it decrease in cel ular thickening and disappearance in becomes more energetic and more able to flow which most elements from the cytoplasm. Additional y, Pengfei can be considered as a birth of new science cal ed et al. (2007) found inhibition in the growth and concen- Magneto biology. He also pointed out that, magnetized tration of Pseudomonas aeruginosa bacteria by using water prevents harmful metals such as, lead and nickel, wireless magneto-elastic, which facilities the sterilization from uptake by roots and reaching fruits and roots. process special y in canned food. However, it increases the percentage of nutrient Therefore, our aim in this study is to improve physical, elements like phosphorus, potassium and zinc. chemical and biological properties of stagnant water, by Magnetic wastewater treatment has been introduced to subjecting samples taken at random from a lake located the chemical industry to remove heavy metals (Tsouris, at Easter Jeddah, to magnetic fields with different 2001) and the magnetic wastewater treatment can also intensities, as a new, safe biological method for man and be applied to remove color, phosphates and oil at low concentration. Some researchers reported that magnetic treatment affects water properties, such as light absorbance, pH, zeta potential and surface tension (Joshi MATERIALS AND METHODS
and Kamat, 1966; Holysz et al., 2002; Chibowski et al.,
Study area
2003; Cho and Lee, 2005). However, these effects have not always been confirmed (Limpert and Raber, 1985; The lake of the study is located in Eastern Jeddah. This lake is Baker et al., 1997). Chibowski et al. (2003) reviewed the considered as one of the environmental problems because it literatures on magnetic field treatment and carried out receives great amount of sewage water daily (50 x 103 m3) by tests on magnetic field effects on precipitated calcium sewage systems. Hence, it is alarming, if it mixes with underground carbonate in wel -defined and control ed systems and water which can cause soil and building col apse, in addition to bad odor that spread and cause health troubles. The size of the lake is conditions. Amiri and Dadkhah (2006) found that changes 9.5 x 106 m3 and its surface 2.6 km2 approximately. in surface tension due to magnetic treatment, can be a key point in tracing impurities in water. Meaningful changes in surface tension of a liquid sample after a day Water samples magnetic field application
can be a good indicator for the presence of physical and Eight water samples were col ected randomly from different chemical changes in the sample. locations in the lake. The samples were mixed together to form a It was observed that magnetized water helps in homogenous sample which was subjected to magnetic fields with dissolving minerals and acids by a higher rate than un- different intensity (µT) treatments. The treatments were 130, 260 magnetized water, in addition to dissolving oxygen and and 390 µT in addition to control. These intensities were measured increasing the speed of chemical reactions (Moon and by Gauss meter in the Faculty of Engineering, University of Sudan Chung, 2000). Smirnov (2003) noticed that water can for Science and Technology. The experiments were done statical y and dynamical y in a shaker incubator of 200 rpm velocity. Each of receive signals produced from magnetic forces that have these treatments was represented by five replicates, resulting in 40 a direct effect on living cel s and their vital action. Hence, experimental units. research is going on to use magnetic field in limiting microbial water pol ution. Abel (2002) pointed out that water pol ution and its red color is caused by reproduction Physical and chemical analysis of water samples
of microscopic living organisms in great rates. It was The physical properties of the samples such as clearness, found that Ferro bacteria (Clonothrix sp. and Creothrix sedimentation, odor, pH and EC were measured, according to sp.) accumulates ferric hydroxide in their cel s and their Chapman and Pratt (1978) by using pH meter WTW model 530 and wal s, causing some troubles in sewers including bad conductivity meter ORION model 160. The results were recorded odor. It also forms adhesive substances which cause every week for 30 days. Some elements such as Ca, Mg, Na, K, Fe, trouble in nutrient labs when water is used in production. P, Pb, Cu and Cl were measured in the laboratory of Water and The presence of Escherichia coli is considered as an Environment, Saudi Society of Area and Geology (community indicator of water pol ution in sewage water (Neil , 2004) and hence higher probability of the presence of microbes that cause intestine diseases such as typhoid, Bacteriological studies
paratyphoid, cholera and intestinal docentaria. El-Sayed et al. (2006) discovered that, when E. coli is subjected to Bacteriological studies were carried out to show the effect of magnetic field on the bacteria counts of Heterotrophic Plate Count a magnetic field (50 hertz) and electromagnetic waves (2 (HPC) after 24 h from col ection and after 30 days from the µT) for different time periods, it caused a great inhibition beginning of the experiment. The studies also used dilution method in the growth of bacteria after 6 h and became more as described by Col ins and Lyne (1985). Series of dilutions were sensitive to antibiotics, with the effects in the prepared from 10 to 1 to 10 to 4. 1 ml sample was taken from each morphological characters which are represented in the dilution into sterilized plates with a suitable amount of prepared decrease in the length of bacterial cel . However, the nutrient agar (Oxoid Company, 3 g beef extract, 5 g peptone, 20 g agar and 1 L distil ed water) at pH 7.2 and was sterilized at 15 results were the opposite after 16 h, accompanied by a Ltd/inch2 for 15 min in autoclave. The plates were incubated at 37°C Molouk and Amna 9 Table 1. Effect of different magnetic intensities of static and shaking treatments on the physical properties of stagnant water of a
lake located at Eastern Jeddah through 30 days. Days of measurements (magnetization)
Treatments
Magnetic intensity ( T)
Clearness
-Unclear - Non sedimentation - No odor; + Low clear + Low sedimentation + Little odor; ++ Clear ++ Medium sedimentation ++ Medium odor; +++ High clear ++ High sedimentation +++ High odor. for 24 h. The heterotrophic bacterial numbers were recorded and efficiency of bio-system. Some researchers have claimed presented by colony forming units (CFU/ml). This count was used that, homogeneous nucleation was increased and gave as a substitution for total bacterial count (Reasoner, 1990). resultant crystals greater in number with smal er sizes Some bacterial isolates which were grown on the prepared nutrient agar were chosen and re-grown on blood agar (3 g beef (Wang et al., 1997 and Ferreux et al., 1993). extract, 10 g treptose, 5 g NaCl, 15 g agar and 1 liter distil ed water The results of pH value showed significant increase and sterilized at 15 LTD /inch2 for 15 min in an autoclave) to study with increasing magnetic intensity in static and shaking some of the properties and distinguish between experimental types treatments (Table 2). However, it was observed that pH (Gratten et al., 1994). Horse blood (5%) was added to the nutrient value was lower in shaking samples than static ones, as agar after reaching temperature of 45°C and was distributed in the plates and then incubated after making lines with bacteria at 37°C it recorded 6.3 and 7.3, respectively at magnetic density for 24 h. The results were used to distinguish the different types of 390 µT after 30 days. However, Maheshwari and Grewal tested bacteria. The hydrolyzed bacteria to blood was from the type (2009) stated that the use of magnetical y treated B-haemolysis, while the non hydrolyzed one was from the type Y- irrigation water reduced soil pH. Busch and Busch (1997) haemolysis, whereas, the type ∝-Haemolysis caused partial reported a change in the pH difference between the hydrolysis and gave a green color (Broughton et al., 1981). In surface and the bulk of magnetical y treated water. addition, gram pigment test was used to distinguish between the different types of bacteria. Statistical analysis (T-test) was done on In addition to the breakage of hydrogen bonds the obtained results by using SPSS program. electromagnetic fields may perturb the gas/liquid interface and produce reactive oxygen species (Colic and Morse, 1999). Changes in hydrogen bonding may affect RESULTS AND DISCUSSION
carbondioxide hydration. The different magnetic densities have an effect on EC of experimented water, at static and Water pol ution is due to the change in physical, chemical shaking treatments. The results in Table 3 show a and biological properties which is either directly or significant decrease in EC values with an increase of indirectly caused by human activity and their derivatives. both magnetic intensity and time. The decrease was A blackish precipitate was found in static samples while a more remarkable for dynamic treated samples than static brown one was found in samples treated by shaking. It is one which recorded 300 and 500 µm at the magnetic thought that modifications to the properties of solutions intensity 390 µT, respectively as compared with EC of the through the magnetic field changes in the molecular control sample (720 and 1003 µm, respectively) after 30 structure of liquids, polarization, resulted from arrange- days. The decrease in EC may be explained as thus, that ment of particles and final y from changes of the electric water treated by magnetic power contains fine col oidal potential (Lebkowska et al., 1991; Szczypiorkowski, 1995 molecules (in the state of constant motion resembling and Krzemieniewski et al., 2002). The present study has Brownian motion) and electrolytic substances which proven that a strong magnetic field, has effects on the respond to magnetic treatment by their increasing ability properties of liquids such as clarity, sedimentation and to sediment that results in a decreased EC. Those results are in accordance with Kronenberg (1985) and Wie et al. Recently, Xu and Sun (2008) have shown that the (2000) who pointed out the role of the magnetic field in magnetized magnetic powder could improve the sludge the increase of water nucleation. Nucleation is a process sedimentation capability, turbidity of out flow and in which ions come together and form nuclei. Malkin (2002) 10 J. Evol. Biol. Res. Table 2. Effect of different magnetic intensities and static and shaking treatments on pH value of stagnant water of a lake
located at Eastern Jeddah. Days of measurements(magnetization)
Treatments
Magnetic
intensity ( T)
Analysis of variance
Between treatments Between magnetic HS = highly significant (P < 0.005) NS = non-significant (P > 0.05). Table 3. Effect of different magnetic intensities and static and shaking treatments on EC value of stagnant water of a lake
located at Eastern Jeddah through 30 days (average ± standard deviation). Days of measurements (magnetization)
Treatments
Magnetic intensity(µT)
Analysis of variance
Between treatments Between magnetic intensities HS = highly significant (P < 0.005) NS= non-significant (P > 0.05). reported that the ions in the water are affected by in the build up of scale, due to the loose nature of the exposure to magnetic fields. A further benefit of the ions which may cause the reduction in EC for samples. alteration in the ion states of both calcium carbonate and The present study showed an inverse proportional magnesium carbonate is that, the change in structure of relationship between nutrient elements and intensities of these compounds (which are the cause of the scale build magnetic fields (Table 4). The element variations in up in water pipes, kettles etc) resulting in much decrease response to magnetic intensity appeared to be variable.
Molouk and Amna 11 Table 4. Chemical analysis of elements in static and shaking samples of stagnant water of a lake located at Eastern
Jeddah after 30 days. Treatments
Magnetic intensity (µT)
Elements (ppm)
>0.18 0.49 6.80 9.20 12.60 15.70 38.90 153.3 254 >0.10 0.12 4.80 8.20 11.50 15.70 34.55 148.0 227 >0.10 0.10 1.77 8.10 9.20 15.20 28.62 147.7 222 >0.10 0.10 1.21 7.80 8.76 15.10 28.42 144.8 208 >0.10 0.20 6.40 8.10 10.61 15.50 31.86 147.9 233 >0.10 >0.10 2.84 8.10 8.52 15.40 30.33 146.7 213 >0.10 >0.10 1.82 7.90 5.53 15.30 27.50 145.3 210 >0.10 >0.10 1.15 7.80 4.88 15.00 20.10 144.5 205 The decreases in both Fe and K were negligible while of organic matter (Szczypiorkowski and Nowak, 1995; they were 80 and >50% in Pb and 15 and 4% in Mg for Goldsworthy et al., 1999). The relatively long detention static and shaking samples, respectively, at the magnetic time in the technological system, which in the second intensity 390 µT. Clear inverse correlations between phase amounted to 48 h, may have positively stimulated metal ic pol utants concentrations and concentration- and determined the growth of some microorganism dependant magnetic characteristics are observed by groups. It seems that the proliferating bacterial biomass Georgeaud (1998) and Matasova et al. (2005). may have taken up the organic substratum present in the Krzemieniewski et al. (2004) revealed that the magnetical y-treated wastewater, which has been magnetization of tap water al ows it to achieve its ful confirmed by laboratory studies of biological degradation oxygenation capacity. Likewise, in the municipal of organic compounds introduced in the magnetic-activity wastewater, the introduction of magnetic field to the area. It was revealed that within the induction range of technological system al owed for carbondioxide, ozone, 0.005 to 0.14 T, the constant magnetic field intensifies hydrogen sulphide and chlorine reduction. biological degradation processes by activated sludge of The results showed that the decreases in P, Ca, Cu, most of the tested organic compounds and pol utants Na and Cl were 82, 27, 30, 6 and 18%, respectively in contained in wastewater. It was also confirmed that, the static state, while they were 82, 37, 54, 2 and 12%, magnetic field's effect on organic compound degradation respectively in shaking state, at the magnetic intensity continues for about 12 h after termination of exposure 390 µT, as compared to the control environment (Table (Lebkowska, 1991). 4). Sodium recorded the least decrease with the increase The results in Table 5 showed that, the highest of magnetic intensity for both treatments. These results numbers of heterotrophic bacteria were recorded with the are considered beneficial as the overconcentration of Na least magnetic intensity (130 µT) where it was 330×10-3 leads to water toxicity for living organisms (Nair et al., and 287x10-3 CFU/ml, for both static and shaking 1989). The decrease can be explained thus, that treatment, respectively. The bacterial numbers were magnetic force breaks hydrogen bonds between water decreased proportional y by the increase in the magnetic molecules, so the ions become separated and combine force intensity. It was recorded that 240 × 10-3 and with elements and precipitate. In addition, Chang and 133×10-3 CFU/ml after 24 h of incubation for both static Weng (2008) showed that the enhanced mobility of the and shaking cases, under the highest magnetic intensity ions under a magnetic field, causes serious damage to 390 µT. The magnetic intensity had even more inhibition the hydrogen bond network in the high Na concentration effect on bacteria after 30 days of magnetic treatment, solution. Conversely, in the low-concentration solution, when bacteria counts were 169.67 x 10-3 and 47.33 x 10-3 the structural behavior is dominated by the properties of CFU/ml, for both static and shaking cases, under the the water molecules and hence the hydrogen bonding highest magnetic fields. This is due to the effect of a ability is enhanced, as the magnetic field is increased. magnet on the metals in treated water, especial y organic The phenomenon of effective penetration of the substances, nitrogen and phosphorus which are essential atmospheric oxygen into the solutions prepared with the in the reactions of bacterial metabolism. Additional y, magnetic field is advantageous from another point of water forms 80% of bacterial cel s, so when its physical view. Most microorganisms breaking down the organic and chemical properties were changed by magnetic compounds are aerobic by nature. Thus, in the force, the growth of bacterial cel s was inhibited as their magnetized liquids, with increased oxygen concentration, composition changed. This is in accordance with Strasak their growth is more intense and so, is the degradation et al. (2002), the ability of bacteria to form decreased 12 J. Evol. Biol. Res. Table 5. Effect of different magnetic intensities on the bacterial numbers (CFU x10-3 /ml) of static and
shaking treatments of stagnant water of a lake located at Jeddah after 1 and 30 days (average ± standard Treatments
Magnetic intensity (µT)
Number of bacteria (CFU x10-3 /ml)
330.00 ± 10.00** 205.67 ± 1.15** 288.00 ± 12.00** 191.67 ± 6.66** 240.00 ± 16.62** 169.67 ± 6.65** 298.00 ± 10.00** 167.67 ± 2.52** 287.00 ± 28.16** 149.67 ± 6.51** 200.00 ± 7.00** 123.00 ± 12.53** ** Highly significant (P < 0.005). Table 6. Morphological and physiological characters of isolated bacteria from stagnant water of a lake located at Eastern Jeddah,
which were grown on agar medium and blood agar. Morphological and physiological characters of isolated bacteria
Isolates Cell shape Movement Catalase activity Gram pigment Haemolysis Coagulase (simmoris)
colonies with increasing magnetic field intensity and with mentioned that some types of heterotrophic bacteria were increasing time of exposure. The decrease in a source of enterogastritis. oxidoreductive activity and ability to form colonies, were Table 6 shows the variations in some morphological compared with the assumption that, the effect of and chemical properties of bacterial isolates. Most magnetic field is probably bactericidal. isolates were negative gram cocci which recorded 56.6 % In addition, Mohamed et al. (1997) found that, the from total isolates, 23.7% from positive gram cocci and exposing of Salmonel a typhi to magnetic force of 10 and 19.7% positive gram bacil us, this indicates the diversity 20 gauss for 2 h, caused changes in the numbers of cel s of microbial pol ution present in the water samples. In in the stationary phase. Piatti et al. (2002) found also addition, some types of bacteria such as Y-haemolysis that, when exposing Serratia marcescens to magnetic (non-decompose blood) and B-haemolysis (decompose force of 80 ± 20 gauss lead to the inhibition of its growth. blood which forming clear halos around themselves) were El-Sayed et al. (2006) confirmed that, the growth of E. found in isolations. The B-haemolysis is considered with coli can be reduced by exposing it to a magnetic intensity other properties as indicators of the kinds of human of 2 µT for 6 h of 50 Hz. Additional y, the growth of harmful bacteria (McFeters, 1990) and as a result, it lead Mycoplasma genitalium was affected by using to many problems in the general health of humans. levofloxacin and tetracycline antibiotics, after being The results of this study concluded that, the biological exposed to a magnetic field, from sensitive wireless treatment of water using magnetic force has a vital role in instruments for different time intervals (He et al., 2009) treating stagnant water; the magnetic flux density This indicates the possibilities of using a magnetic force increases the values of physical, chemical and to inhibit bacterial growth in water. However, the bacteriological properties. This is one of the interesting presence of bacterial pol utants in water, also leads to findings in this field of research. This encourages more appearance of some diseases like cholera, bacterial research in this field. Using magnetism to overcome dysentery, typhoid, diarrhea, hepatitis and other epidemic negative effects of water pol ution is considered a diseases (Abd-Al ah, 1991). Payment et al. (1991) potential technology. It should be adapted to suit Molouk and Amna 13 environmental and climatic conditions so that its use can genitalium growth and evaluation of antibacterial activity of antibiotics tetracycline and levofloxacin using a wireless magneto elastic sensor.1: Biosens. Bioelectron, 24(7): 1990-1994. Holysz L, Chibowski M, Chibowski E (2002). Time dependent changes of zeta potential and other parameters of in situ calcium carbonate due to magnetic field treatment. Col oids Surf. A, 208: 231-240. Johan S, Fadil O, Zularisham A (2004). Effect of Magnetic Fields on The authors acknowledge Professor D. Masarrat Suspended Particles in Sewage. Malaysian J. Sci., 23: 141– 148. Joshi KM, Kamat PV (1966). Effect of magnetic fields on the physical Mohamed Abd Elaziz Migahid for her help and general properties of water. J. Ind. Chem. Soc., 43: 620-622. assistance in the review of the manuscript. Krzemieniewski M, Dobrzynska A, Janczukowicz W, Pesta J, Zielinski M (2002). Effect of constant magnetic field on the process of generating hydroxyl radicals wreakcji Fenton. Chemist., 1: 12. Krzemieniewski M, D bowski M, Janczukowicz W, Pesta J (2004). REFERENCES
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