Southwest Giza area is one of the most complicated regions in Egypt because of the combination of agricultural, industrial and urbanization activities with few studies about water resources contamination with heavy metals. In this study, ten surface water samples and eight groundwater samples were collected and analyzed for pollution with Fe, Mn, As, Cr, Cd, Pb and Cu. The samples were collected randomly according to the topographic locations and accessibility. The surface water is suitable for both drinking and irrigation use according to its salinity (total dissolved solids, TDS < 500 mg/l) and content of major ions. Unfortunately, some samples contain concentrations of As, Cd, Cu and Pb higher than the WHO drinking water guidelines. The groundwater samples have TDS ranging from 204 to 2,100 mg/l. Also, the groundwater contains higher concentrations of Fe, Mn and As than surface water. The highest concentrations of heavy metals As, Cd and Pb were recorded in the desert fringes and close to the industrial complexes indicating the role of geological sediments in the transportation and migration of pollutants. The unconfined part of the Quaternary aquifer in the desert fringes is more vulnerable to contamination. The results of this study reflect the role of human and industrial activates in polluting water resources with heavy metals, which puts the aquatic environment in the study area under stress.

INTRODUCTION

One of the major environmental hazards in some parts of the world is the pollution of water resources with heavy metals (Matong et al. 2016). The pollution of aquatic environments with these metals can be poisonous and affect not only humans but also fish and other aquatic organisms (Zeitoun & Mehana 2014). Some heavy metals (e.g. Fe, Mn, Cu and Cr) have a biochemical importance and are considered as micronutrients at low concentrations. But others such as As, Cd, Pb and Hg may cause cancer, renal failure, brain and liver damage (Patel et al. 2005; Zakir et al. 2012; Melegy et al. 2014). Many industrial zones were constructed on both the banks of the River Nile without concern for water and soil pollution (Mahmoud & Ghoneim 2016). More than 549 × 106 m3/yr of industrial wastewater (El-Sheekh 2009) are discharged into the River Nile from about 700 factories (Hussein 2015). Industrial wastewater always contains high concentrations of harmful microorganisms, organics, heavy metals and solid substances (Ali et al. 2011). The study area is located in south Giza on the western bank of the Nile River between longitudes 31° 13′ 08″ and 31° 19′ 53″ and latitudes 29° 46′ 40″ and 29° 54′ 00″ (Figure 1). The study area included many big industries such as sugar, chemical, wood and red brick factories. In addition, the area includes continuing urbanization, tourism and agriculture activities. Sugar and chemical industries at Giza are one of the most important pollution sources of the River Nile (Ali et al. 2011). Zaki et al. (2015) highlighted the role of agro-industries (Sugar factory in Abo Qurqas city and Onion factory in Maghagha city) at El Minia governorate (Central Egypt) in the pollution of water resources with As, Co, Hg, Ni, Se, Cd and Cr.
Figure 1

Location and geological map of the study area showing the sampling sites.

Figure 1

Location and geological map of the study area showing the sampling sites.

The geology of the study area is composed mainly of sedimentary rocks (Figure 1). The surface water hydrology of the study area is represented by the River Nile, irrigation canals and drains. The main groundwater aquifer is the Quaternary aquifer system. This aquifer is composed of Pleistocene sand and gravel sediments with a thickness of 50 m adjacent to the River Nile course and decreases westwards in the desert fringes to few metres (Awad 2012). The aquifer is covered by the semi–permeable Nile silt in the old cultivated land, while it is overlain by the Wadi deposits in the old alluvial plains. The lower part of this aquifer is composed of mixed shale, sand and gravels of The Plio-Pleistocene sediments (RIGWA 1980). This aquifer is underlined by the thick (1,300 m) Eocene carbonate aquifer which crops out in the western desert area (Said 1990). The aquifer can be recharged from the River Nile, canal, irrigation water and drains and wastewater from the residential and industrial areas (Awad 2012). The objective of this work is to assess water pollution with heavy metals and the role of urbanization, agricultural and industrial activities in the distribution of metals in southwest Giza, Egypt.

METHODOLOGY

To fulfil the aim and scope of this study, 18 water samples were collected during October 2015 (Figure 1). The topography, the land use, the area of the study sites (about 25*10 km) and the accessibility to sample locations control the number and distribution of the samples. Ten representative water samples were collected from surface water (S1–S10) and eight samples from wells used for domestic purposes (G1–G8). Water samples were collected in 1 L plastic bottles for physicochemical analyses. For each sampling point, each plastic bottle was rinsed three times with the water to be sampled, filled to the brim and sealed tightly. The pH, temperature (T °C), electrical conductivity (EC) and total dissolved solids (TDS) were determined in the field using combined electrode (HANNA HI93300). In the laboratory, all samples were filtered and split in to different polyethylene bottles for subsequent analyses of cations and anions.

The samples were analyzed for chemical constituents by using the standard procedures of APHA (2005). Sodium and K were determined by flame photometer. Total hardness as CaCO3, carbonate (CO32−), bicarbonate (HCO3) and chloride (Cl) were analyzed by volumetric methods. Sulfates (SO42−), nitrate, ammonia and phosphate were estimated by using the calorimetric technique. The cations; Ca, Mg, Pb, Fe, Mn, Cd, As and Cu were determined by Atomic Absorption Spectrophotometer (model AA 650). High purity chemicals, double distilled water, high precision balance (ADAM PW 124, ±0.0001 g) were used in all analyses. Also, all chemical analyses were done in triplicate.

RESULTS AND DISCUSSION

General characteristics

The groundwater and surface water measured parameters are illustrated in Table 1. The pH ranges of surface and groundwater samples were 7.25–8.06 and 7.13–8.09, respectively. This slightly alkaline pH is preferable in waters, as heavy metals are removed by carbonate or bicarbonate precipitates (Ahipathy & Puttaiah 2006). The high pH values of surface and groundwater samples may have resulted from the interaction between limestone deposits and water resources in the area. The higher pH values of surface water compared to groundwater may have resulted from the role of biota in surface water, where it consumes carbon dioxide leading to a higher pH level (Hem 1985).

Table 1

Measured parameters of surface water and groundwater samples

S. No. pH TDS mg/l EC μS/cm Ca mg/l Mg mg/l Na mg/l K mg/l HCO3 mg/l SO4 mg/l Cl mg/l NO3 mg/l NH4 mg/l 
Surface water samples 
 S1 7.95 204 408 33.8 16.8 30.0 6.4 25 65.4 75.0 41.8 2.95 
 S2 8.09 192 396 31.5 13.9 28.9 5.8 15 112 65.7 2.61 
 S3 7.78 228 456 29.7 16.4 31.8 5.3 20 85.4 94.8 5.9 0.75 
 S4 8.06 216 432 38.8 13.9 29.9 5.3 15 95.6 52.2 56.7 2.37 
 S5 7.25 240 480 38.5 15.8 33.3 7.4 20 122 74.5 16.8 2.13 
 S6 7.81 228 444 33.6 12.6 29.3 6.3 15 90.6 75.3 18.4 1.65 
 S7 7.99 204 400 32.8 14.0 28.0 6.3 15 109.8 47.4 10.1 2.01 
 S8 7.75 348 708 53.1 26.5 61.7 7.0 55 118.8 125.9 18.6 1.8 
 S9 7.77 216 420 32.8 21.1 31.0 5.2 20 85.4 81.3 4.6 0.66 
 S10 7.54 216 420 34.4 20.3 28.8 5.0 15 97.6 67.7 14.3 1.29 
Mean 7.8 229.2 456.4 35.9 17.1 33.3 6.0 21.5 98.3 76.0 19.5 1.8 
Groundwater samples 
 G1 7.4 204 408 35 15.2 33.0 5.4 25 97.6 67.7 7.4 1.87 
 G2 7.66 840 1,680 65.9 61.0 170.7 7.4 155 270.4 226.7 13.7 3.97 
 G3 7.92 1,956 3,864 186.3 98.0 638.7 33.5 400 920 820.3 71 1.84 
 G4 7.58 672 1,344 81.5 47.0 98.4 34.3 99 229.6 199.4 11 2.48 
 G5 7.13 660 1,332 118.2 50.3 85.9 7.6 95 215.4 237.0 18.5 1.48 
 G6 7.19 2,100 4,176 207.0 65.8 569.7 32.9 360 272.8 1,188.6 6.2 
 G7 8.09 972 1,968 51.6 55.4 328.8 14.8 325 48.8 555.2 9.6 1.81 
 G8 7.29 1,500 3,036 60.0 75.0 368.6 12.1 400 145.4 622.9 38.9 2.97 
Mean 7.5 1,113 2,226 100.7 58.5 286.7 18.5 232.4 275 489.7 22 2.4 
S. No. pH TDS mg/l EC μS/cm Ca mg/l Mg mg/l Na mg/l K mg/l HCO3 mg/l SO4 mg/l Cl mg/l NO3 mg/l NH4 mg/l 
Surface water samples 
 S1 7.95 204 408 33.8 16.8 30.0 6.4 25 65.4 75.0 41.8 2.95 
 S2 8.09 192 396 31.5 13.9 28.9 5.8 15 112 65.7 2.61 
 S3 7.78 228 456 29.7 16.4 31.8 5.3 20 85.4 94.8 5.9 0.75 
 S4 8.06 216 432 38.8 13.9 29.9 5.3 15 95.6 52.2 56.7 2.37 
 S5 7.25 240 480 38.5 15.8 33.3 7.4 20 122 74.5 16.8 2.13 
 S6 7.81 228 444 33.6 12.6 29.3 6.3 15 90.6 75.3 18.4 1.65 
 S7 7.99 204 400 32.8 14.0 28.0 6.3 15 109.8 47.4 10.1 2.01 
 S8 7.75 348 708 53.1 26.5 61.7 7.0 55 118.8 125.9 18.6 1.8 
 S9 7.77 216 420 32.8 21.1 31.0 5.2 20 85.4 81.3 4.6 0.66 
 S10 7.54 216 420 34.4 20.3 28.8 5.0 15 97.6 67.7 14.3 1.29 
Mean 7.8 229.2 456.4 35.9 17.1 33.3 6.0 21.5 98.3 76.0 19.5 1.8 
Groundwater samples 
 G1 7.4 204 408 35 15.2 33.0 5.4 25 97.6 67.7 7.4 1.87 
 G2 7.66 840 1,680 65.9 61.0 170.7 7.4 155 270.4 226.7 13.7 3.97 
 G3 7.92 1,956 3,864 186.3 98.0 638.7 33.5 400 920 820.3 71 1.84 
 G4 7.58 672 1,344 81.5 47.0 98.4 34.3 99 229.6 199.4 11 2.48 
 G5 7.13 660 1,332 118.2 50.3 85.9 7.6 95 215.4 237.0 18.5 1.48 
 G6 7.19 2,100 4,176 207.0 65.8 569.7 32.9 360 272.8 1,188.6 6.2 
 G7 8.09 972 1,968 51.6 55.4 328.8 14.8 325 48.8 555.2 9.6 1.81 
 G8 7.29 1,500 3,036 60.0 75.0 368.6 12.1 400 145.4 622.9 38.9 2.97 
Mean 7.5 1,113 2,226 100.7 58.5 286.7 18.5 232.4 275 489.7 22 2.4 

Surface water TDS flocculated around 229.2 mg/l. The highest concentration of TDS was observed in the sample S8, which represented the irrigation canal adjacent to the calcareous desert area. The groundwater TDS (Table 1) varies from one location to another from 204 mg/l to 2,100 mg/l. It appears that the wells close to the River Nile course possess a lower concentration of TDS than the others to the west as a result of surface water percolation in the dilution of groundwater. The high TDS values may be attributed to the leaching of salts from Plio-Pleistocene sediments containing salts of sulfates and chlorides (Elewa 2004).

The EC of surface water (Table 1) ranges from 400 to 708 μS/cm. The high EC levels resulted from the high concentration of TDS mineralization of organic materials (Abida & Harikrishna 2008). The groundwater samples had EC values (408–4,176 μS/cm) greater than that of surface water (Table 1); which indicates a high concentration of dissolved solids and salts. The large variation in EC is mainly attributed to geochemical processes such as ion exchange, rock–water interaction, sulfate reduction and oxidation processes (Ramesh 2008).

Major cations and anions

The surface water contents of Ca2+, Mg2+, Na+, K+, NH4, Cl, SO42−, HCO3 and NO3 were flocculated around 35.9, 17.1, 33.3, 6, 1.8, 76, 98.3, 21.5 and 19.5 mg/l, respectively (Table 1). The significant positive correlation of Ca2+ and Mg2+ with HCO3, Cl and SO4² (Table 2) suggests that the dissolution of carbonate and sulfate minerals and irrigation effluents are the main sources of these ions in water (Greenwood & Earnshaw 2002). Potassium in river water is primarily from leaching of silicate minerals, small amounts of fertilizers and decay of land plants (Chaudhuri et al. 2005). Nitrate presence in the surface water and groundwater may result from the application of fertilizers and manures in agriculture (Eltarabily et al. 2016), wastewater disposal and the oxidation of nitrogenous waste products in human and animal excreta (WHO 2011). Ammonia in the environment originates from metabolic, agricultural and industrial processes. The natural level of NH4 in water resources is usually below 0.2 mg/l. Accordingly, the high levels of NH4 in the studied water (Table 1) is an indicator of possible bacterial, sewage and animal waste pollution (WHO 2011).

Table 2

Correlation matrix between the studied ions in surface water samples

 Ca Mg Na HCO3 SO4 Cl NO3 NH4 Fe Mn As Cd Pb Cu 
Ca 1.00               
Mg 0.66 1.00              
Na 0.91 0.78 1.00             
0.52 0.07 0.47 1.00            
HCO3 0.86 0.80 0.97 0.48 1.00           
SO4 0.49 0.13 0.41 0.47 0.25 1.00          
Cl 0.60 0.76 0.84 0.30 0.86 0.09 1.00         
NO3 0.26 −0.19 −0.03 0.03 0.02 −0.30 −0.25 1.00        
NH4 0.16 −0.36 −0.05 0.46 0.01 0.10 −0.34 0.60 1.00       
Fe 0.45 0.50 0.56 0.60 0.61 0.15 0.71 −0.15 −0.14 1.00      
Mn −0.38 −0.23 −0.19 −0.46 −0.22 −0.17 0.04 −0.12 −0.36 −0.01 1.00     
As 0.08 −0.43 −0.11 0.39 −0.06 0.09 −0.39 0.61 0.96 −0.15 −0.17 1.00    
Cd −0.13 −0.19 −0.15 0.16 0.04 −0.64 −0.10 0.55 0.63 0.00 −0.21 0.58 1.00   
Pb −0.43 −0.35 −0.22 −0.14 −0.10 −0.45 −0.04 0.05 0.28 −0.16 0.47 0.31 0.59 1.00  
Cu 0.35 −0.03 0.27 0.83 0.21 0.54 0.22 −0.10 0.15 0.68 −0.26 0.12 −0.19 −0.39 1.00 
Cr −0.45 −0.23 −0.31 −0.10 −0.14 −0.52 −0.11 0.11 0.46 −0.08 0.15 0.48 0.76 0.79 −0.35 
 Ca Mg Na HCO3 SO4 Cl NO3 NH4 Fe Mn As Cd Pb Cu 
Ca 1.00               
Mg 0.66 1.00              
Na 0.91 0.78 1.00             
0.52 0.07 0.47 1.00            
HCO3 0.86 0.80 0.97 0.48 1.00           
SO4 0.49 0.13 0.41 0.47 0.25 1.00          
Cl 0.60 0.76 0.84 0.30 0.86 0.09 1.00         
NO3 0.26 −0.19 −0.03 0.03 0.02 −0.30 −0.25 1.00        
NH4 0.16 −0.36 −0.05 0.46 0.01 0.10 −0.34 0.60 1.00       
Fe 0.45 0.50 0.56 0.60 0.61 0.15 0.71 −0.15 −0.14 1.00      
Mn −0.38 −0.23 −0.19 −0.46 −0.22 −0.17 0.04 −0.12 −0.36 −0.01 1.00     
As 0.08 −0.43 −0.11 0.39 −0.06 0.09 −0.39 0.61 0.96 −0.15 −0.17 1.00    
Cd −0.13 −0.19 −0.15 0.16 0.04 −0.64 −0.10 0.55 0.63 0.00 −0.21 0.58 1.00   
Pb −0.43 −0.35 −0.22 −0.14 −0.10 −0.45 −0.04 0.05 0.28 −0.16 0.47 0.31 0.59 1.00  
Cu 0.35 −0.03 0.27 0.83 0.21 0.54 0.22 −0.10 0.15 0.68 −0.26 0.12 −0.19 −0.39 1.00 
Cr −0.45 −0.23 −0.31 −0.10 −0.14 −0.52 −0.11 0.11 0.46 −0.08 0.15 0.48 0.76 0.79 −0.35 

On the other hand, the groundwater samples contained a higher concentration of ions than the surface water. It contained about 110.7, 58.5, 286.7, 18.5, 2.4, 489.7, 275, 232.4 and 22 mg/l of Ca2+, Mg2+, Na+, K+, NH4, Cl, SO42−, HCO3 and NO3, respectively (Table 1). The significant positive correlation of Ca2+ with Mg2+ (r = 0.60), Na+ (r = 0.74), K+ (r = 0.70), Cl (r = 0.77) and (SO4)2− (r = 0.68) (Table 3), indicates the leaching of Ca from clays, dissolution of sulfate and carbonate minerals from Pleistocene sediments. Another important source of Ca2+ in the groundwater is the recharging of mixed irrigation water with fertilizers (Ahmed & Ali 2011) or with sewage effluents. While the Mg2+ source is the dissolution of clay minerals as supported by the positive relationship of Mg2+ with Na+ (r = 0.83), K+ (r = 0.49) and Cl (r = 0.68) (Table 3). Sodium represents the dominant cation in the analyzed groundwater samples. One of the main sources of Na+ in groundwater is the dissolution of Na-bearing minerals of the Pliocene marine sediments of the Nile valley (Omer 2003). The high content of Na+ in some samples may result from the direct effect of alkaline soils and fertilizer used in agriculture or may be attributed to the base exchanging and leaching of sodium salts such as halite during the movement of groundwater through sediments (Ahmed & Ali 2011). This can be evidence of the strong significant correlation (r = 0.94) between Na+ and Cl (Table 3). The anthropogenic sources of Cl in groundwater can be attributed to irrigation water that is polluted with fertilizers and to sewage effluents (Mashburn & Sughru 2004). The excess of bicarbonate may result from the dissolution of carbonate-rich formation rocks of the area. The high variability of SO42− implies that the factors affecting the groundwater content are mixed. So, the natural processes related to the sediment–water interaction and human activities are essential factors in their presence. The excess of NO3 over 5 mg/l indicates its sanitation source (Kacaroglu & Gunay 1997). Groundwater may also have nitrate contamination as a consequence of leaching from natural vegetation (WHO 2011).

Table 3

Correlation matrix between the studied ions in groundwater samples

 Ca Mg Na HCO3 SO4 Cl NO3 NH4 Fe Mn As Cd Pb Cu 
Ca 1.00               
Mg 0.60 1.00              
Na 0.74 0.83 1.00             
0.70 0.49 0.61 1.00            
HCO3 0.48 0.83 0.92 0.43 1.00           
SO4 0.68 0.72 0.62 0.56 0.40 1.00          
Cl 0.77 0.68 0.94 0.60 0.86 0.39 1.00         
NO3 0.38 0.78 0.59 0.30 0.56 0.83 0.32 1.00        
NH4 −0.04 0.19 0.09 −0.01 0.14 −0.10 0.13 −0.17 1.00       
Fe 0.74 0.17 0.35 0.33 0.08 0.46 0.43 0.25 −0.06 1.00      
Mn −0.75 −0.63 −0.72 −0.62 −0.59 −0.56 −0.69 −0.39 0.36 −0.18 1.00     
As 0.77 0.55 0.67 0.55 0.41 0.62 0.65 0.24 0.48 0.52 −0.45 1.00    
Cd 0.53 0.71 0.73 0.70 0.61 0.83 0.50 0.78 −0.29 0.12 −0.72 0.39 1.00   
Pb 0.59 0.50 0.69 0.33 0.61 0.32 0.75 0.30 0.47 0.66 −0.12 0.66 0.16 1.00  
Cu 0.00 0.08 −0.04 −0.20 −0.09 −0.01 −0.03 −0.24 0.83 −0.07 0.23 0.56 −0.33 0.22 1.00 
Cr −0.47 −0.43 −0.28 −0.49 −0.35 −0.03 −0.43 −0.03 −0.03 −0.11 0.49 −0.10 −0.12 −0.14 0.16 
 Ca Mg Na HCO3 SO4 Cl NO3 NH4 Fe Mn As Cd Pb Cu 
Ca 1.00               
Mg 0.60 1.00              
Na 0.74 0.83 1.00             
0.70 0.49 0.61 1.00            
HCO3 0.48 0.83 0.92 0.43 1.00           
SO4 0.68 0.72 0.62 0.56 0.40 1.00          
Cl 0.77 0.68 0.94 0.60 0.86 0.39 1.00         
NO3 0.38 0.78 0.59 0.30 0.56 0.83 0.32 1.00        
NH4 −0.04 0.19 0.09 −0.01 0.14 −0.10 0.13 −0.17 1.00       
Fe 0.74 0.17 0.35 0.33 0.08 0.46 0.43 0.25 −0.06 1.00      
Mn −0.75 −0.63 −0.72 −0.62 −0.59 −0.56 −0.69 −0.39 0.36 −0.18 1.00     
As 0.77 0.55 0.67 0.55 0.41 0.62 0.65 0.24 0.48 0.52 −0.45 1.00    
Cd 0.53 0.71 0.73 0.70 0.61 0.83 0.50 0.78 −0.29 0.12 −0.72 0.39 1.00   
Pb 0.59 0.50 0.69 0.33 0.61 0.32 0.75 0.30 0.47 0.66 −0.12 0.66 0.16 1.00  
Cu 0.00 0.08 −0.04 −0.20 −0.09 −0.01 −0.03 −0.24 0.83 −0.07 0.23 0.56 −0.33 0.22 1.00 
Cr −0.47 −0.43 −0.28 −0.49 −0.35 −0.03 −0.43 −0.03 −0.03 −0.11 0.49 −0.10 −0.12 −0.14 0.16 

Heavy metal characteristics

The study area (about 25 × 10 km) contains agriculture, industrial and urban sectors. Land use, financial support and accessibility to the sampling sites control the number of samples. Varying concentrations of Fe, Mn, As, Cd, Pb, Cu and Cr were detected in the surface water samples (Table 4). Generally, the samples contained low levels of Fe, Mn, Cu and Cr except for the samples close to the factories which contained a high level of Cr. Arsenic, Cd and Pb are at levels greater than the limits set by the WHO (2011) guidelines for drinking water quality. The highest concentrations of these metals were recorded in the Nile samples close to the industrial zone. Sugar factory wastewater effluents in the study area contained about 2.633 and 10.07 mg/l of Pb and Cd respectively (Ali et al. 2011). Also, Melegy et al. (2014) pointed out the role of sugar factories in the Sohag governorate in increasing pollution of the River Nile by Pb and Cd. The surface water resources at El Minia governorate contained the following ranges, 0.1–1,365, 0.1–2,086.3, 1–14,600 and 1–1,652 μg/l of As, Cd, Pb and Cr, respectively (Zaki et al. 2015). It is obvious that the polluted water streams in Egypt are always subjected to industrial and agricultural impact. The domestic use of polluted water with heavy metals has an adverse effect on human health (Wang et al. 2010; Melegy et al. 2014). Even if the water contains low levels of heavy metals, the aquatic fauna (Fish) could accumulate significant concentrations of these metals in their different organs (El-Naggar et al. 2009). A strong positive relationship between heavy metal levels in water and fish tissues was recorded by Zeitoun & Mehana (2014). The exposure to As, Pb and Cd represents one of the main threats to human health (Jarup 2003). Many studies have pointed out that high levels of heavy metals in the different organs of fishes from different localities of River Nile were recorded (El-Naggar et al. 2009; Ibrahim & Omar 2013). So, the presence of heavy metals in the River Nile water can directly or indirectly affect human health (El-Naggar et al. 2009; Melegy et al. 2014). The urbanization, agricultural and industrial activities in the study area are the main sources of the studied heavy metals as indicated by the positive correlation between metals and K, NO3 and NH4 (Table 2). Whereas, the main sources of K, NO3 and NH4 are manure, fertilizers, industrial and municipal wastes.

Table 4

Heavy metal contents (μg/l) in the studied water samples

  Fe Mn As Cd Pb Cu Cr 
Surface water 
 S1 18 98.4 51 66 20 135 
 S2 300 93.4 59 10 105 
 S3 20 900 20.0 68 20 60 
 S4 400 90.2 10 38 15 
 S5 29 100 72.4 24 190 10.5 
 S6 40.0 10 40 70 13.5 
 S7 100 64.0 49 30 24 
 S8 25 48.0 35 70 4.5 
 S9 14 200 17.6 26 28.5 
 S10 20.0 31 21 
Mean 14 200 56.4 9.5 44 41 41.7 
Groundwater 
 G1 29 600 0.0 32 39 
 G2 18 500 178.8 36 60 21 
 G3 34 100 203.8 22 43 15 
 G4 20 400 37.5 25 
 G5 31 300 0.0 26 
 G6 41 200 253.8 58 20 
 G7 200 0.0 21 12 
 G8 23 500 0.0 49 
 Mean 25 350 84.2 5.75 36 10 11.6 
WHO (2011)  300 400 10 10 2,000 50 
  Fe Mn As Cd Pb Cu Cr 
Surface water 
 S1 18 98.4 51 66 20 135 
 S2 300 93.4 59 10 105 
 S3 20 900 20.0 68 20 60 
 S4 400 90.2 10 38 15 
 S5 29 100 72.4 24 190 10.5 
 S6 40.0 10 40 70 13.5 
 S7 100 64.0 49 30 24 
 S8 25 48.0 35 70 4.5 
 S9 14 200 17.6 26 28.5 
 S10 20.0 31 21 
Mean 14 200 56.4 9.5 44 41 41.7 
Groundwater 
 G1 29 600 0.0 32 39 
 G2 18 500 178.8 36 60 21 
 G3 34 100 203.8 22 43 15 
 G4 20 400 37.5 25 
 G5 31 300 0.0 26 
 G6 41 200 253.8 58 20 
 G7 200 0.0 21 12 
 G8 23 500 0.0 49 
 Mean 25 350 84.2 5.75 36 10 11.6 
WHO (2011)  300 400 10 10 2,000 50 

The concentrations of Fe, Mn, As, Cd, Cu, Pb and Cr in groundwater samples were 5–41, 100–600, BDL-253, BDL-22, 21–58, BDL-60 and BDL-39 μg/l, respectively (Table 4). The high concentrations of Fe and Mn in the studied samples indicate the role of natural water–rock interaction. The Pleistocene deposits (water bearing formation) contain abundant ferromagnesian minerals which represent the source of iron and manganese in the groundwater (Omer 2003). The studied samples have revealed that Fe, Cr and Cu concentrations were within the permissible limits of WHO (2011) guidelines for drinking water. However, the results showed that Mn, Pb, As and Cd were detected in high concentration in most of the analyzed samples. This water is used for domestic purposes in the study area without any regard to its quality parameters. The groundwater at El Minia governorate contains about 118, 91.9, 182.6, 160.6 and 750 μg/l of As, Cd, Pb, Cr and Mn, respectively (Zaki et al. 2015). The contamination of groundwater due to heavy metals is one of the most important concerns because of their toxicological importance in the ecosystems and impact on public health (Ullah et al. 2009). Arsenic is highly mobile and can be leached and transported from soil (Roberts et al. 2010) downward to the groundwater aquifer (Busbee et al. 2009). The heavy metals are also discharged by industries, municipal wastes, hazardous waste sites, fertilizers for agricultural purposes and accidental oil spillages from tankers and can result in a steady rise in contamination of groundwater (Igwilo et al. 2006). The highest levels of heavy metals such as As, Cd and Pb were recorded in the desert fringes and close to the industrial areas. This indicates the high vulnerability of the unconfined part of the aquifer in the desert area to pollution and stress due to industrialization and agricultural activities. The positive correlation between the studied metals and both cations and anions indicates the intermixed processes including the natural water–rock interaction and human activities (Table 3). The study area and the River Nile in general need periodic studies for assessment of water quality. Organic, inorganic and biological pollutants should be measured, especially in the industrial regions.

CONCLUSIONS AND RECOMMENDATIONS

The study area is located in southwest Giza, Egypt. The geological settings, industrial, agricultural and urbanization activities in the study area have impacted the physicochemical characteristics of both surface water and groundwater. Both surface water and groundwater contain considerable concentrations of As, Pb and Cd. The presence of these metals can adversely impact aquatic fauna and human health.

The present work indicates the importance of controlling the discharge of wastewater into water resources, as well as the application of fertilizers and pesticides in agriculture. Periodic assessment of water quality should be carried out especially in urban and industrial regions. Finally, the potable water and sanitation system should be expanded to all residential sectors to prevent the use of untreated water for different purposes.

REFERENCES

REFERENCES
Abida
B.
Harikrishna
2008
Study on the quality of water in some streams of Cauvery River
.
E-Journal of Chemistry
5
(
2
),
377
384
.
Ahipathy
M. V.
Puttaiah
E. T.
2006
Ecological characteristics of Vrishabhavathy River in Bangalore (INDIA)
.
Environmental Geology
49
(
8
),
1217
1222
.
Ali
S. M.
Sabae
S. Z.
Fayez
M.
Monib
M.
Hegazi
N. A.
2011
The influence of agro-industrial effluents on River Nile pollution
.
Journal of Advanced Research
2
,
85
95
.
APHA (American Public Health Association)
2005
Standard Methods for the Examination of Water and Wastewater, 21st edn. Washington, DC.
Awad
S. R.
2012
Hydrogeology, hydrochemistry and pollution of groundwater in the south of Giza area, Egypt
.
Water Science
52
,
65
82
.
Chaudhuri
S.
Clauer
N.
Semhi
K.
2005
Potassium in global river: a new perspective on the source characterization
.
Geophysical Research Abstracts
7
,
10402
.
Elewa
S. A.
2004
Effect of the Construction of Aswan High Dam on the Groundwater in the Area between Qena and Sohag, Nile Valley, Egypt
.
PhD Thesis
,
Faculty of Science, Assiut University
,
Egypt
.
El-Naggar
A. M.
Mahmoud
S. A.
Tayel
S. I.
2009
Bioaccumulation of some heavy metals and histopathological alterations in liver of Oreochromis niloticus in relation to water quality at different localities along the River Nile, Egypt
.
World Journal of Fish and Marine Sciences
1
(
2
),
105
114
.
El-Sheekh
M.
2009
River Nile pollutants and their effect on life forms and water quality
. In:
Dumont
H. J.
(ed.),
The Nile: origin, environments, limnology and human use
.
Series: Monographiae Biologicae 89, Springer, Dordrecht, pp. 395–406
.
Eltarabily
M. G.
Negm
A. M.
Yoshimura
C.
Saavedra
O. C.
2016
Modeling the impact of nitrate fertilizers on groundwater quality in the southern part of the Nile Delta, Egypt
.
Water Science and Technology: Water Supply
ws2016162. doi:10.2166/ws.2016.162
.
Greenwood
N. N.
Earnshaw
A.
2002
Chemistry of the Elements
,
2nd edn
.
Butterworth-Heinemann
,
Oxford
.
Hem
J. D.
1985
Study and Interpretation of the Chemical Characteristics of Natural Water
,
3rd edn
.
US Geological Survey
, Alexandria, Virginia, p.
264
.
Hussein
S. K.
2015
A novel prototype model for monitoring the factories remnants on Nile River
.
International Journal of Engineering Research and Applications
5
(
3
),
83
87
.
Ibrahim
A. T. A.
Omar
H. M.
2013
Seasonal variation of heavy metals accumulation in muscles of the African Catfish Clarias gariepinus and in River Nile water and sediments at Assiut Governorate, Egypt
.
Journal of Biology and Earth Sciences
3
(
2
),
B236
B248
.
Igwilo
I. O.
Afonne
O. J.
Maduabuchi
U. J.
Orisakwe
O. E.
2006
Toxicological study of the Anam River in Otuocha, Anambra State, Nigeria
.
Archives of Environmental & Occupational Health
61
(
5
),
205
208
.
Jarup
L.
2003
Hazards of heavy metal contamination
.
British Medical Bulletin
68
,
167
182
.
Kacaroglu
F.
Gunay
G.
1997
Groundwater nitrate pollution in an alluvium aquifer, Eskisehir urban area and its vicinity, Turkey
.
Environmental Geology
31
(
3
),
178
184
.
Mashburn
S. L.
Sughru
M. P.
2004
Chloride in Groundwater and Surface Water in the Vicinity of Selected Surface-Water Sampling Sites of the Beneficial use Monitoring Program of Oklahoma, 2003
.
USGS/SIR 2004–5060
.
Melegy
A. A.
Shaban
A. M.
Hassaan
M. M.
Salman
S. A.
2014
Geochemical mobilization of some heavy metals in water resources and their impact on human health in Sohag Governorate, Egypt
.
Arabian Journal of Geosciences
7
,
4541
4552
.
Omer
A. A. M.
2003
Impact of the Pleistocene Nile basin sediments on the distribution of iron and manganese in the groundwater, Tema-Nag Hammadi area, Nile Valley, Egypt
. In:
The 3rd International Conference on the Geology of Africa
,
Assiut
,
Egypt
,
1
, pp.
21
23
.
Patel
K. S.
Shrivas
K.
Brandt
R.
Jakubowski
N.
Corns
W.
Hoffman
P.
2005
Arsenic contamination in water, soil, sediment and rice of central India
.
Environmental Geochemistry and Health
27
(
2
),
131
145
.
Ramesh
K.
2008
Hydrochemical Studies and Effect of Irrigation on Groundwater Quality in Tondiar Basin, Tamil Nadu
.
PhD Thesis
,
Anna University
,
Chennai
,
India
, p.
182
.
RIGWA
1980
Project of Safe Yield Study for Groundwater Aquifers in the Nile Delta and Upper Egypt. Part 1
(In Arabic).
Ministry of Irrigation, Academy of Scientific Research and Technology, and Organization of Atomic Energy
,
Egypt
.
Roberts
L. C.
Hug
S. J.
Dittmar
J.
Voegelin
A.
Kretzschmar
R.
Wehrli
B.
Cirpka
O. A.
Saha
G. C.
Ali
M. A.
Badruzzaman
A. B. M.
2010
Arsenic release from paddy soils during monsoon flooding
.
Nature Geoscience
3
,
53
59
.
Said
R.
1990
The Geology of Egypt
.
Balkema
, Rotterdam, p.
734
.
Ullah
R.
Malik
R. N.
Qadir
A.
2009
Assessment of groundwater contamination in an industrial city, Sialkot, Pakistan
.
African Journal of Environmental Science and Technology
3
(
12
),
429
446
.
Wang
S.
Jia
Y.
Wang
S.
Wang
X.
Wang
H.
Zhao
Z.
Liu
B.
2010
Fractionation of heavy metals in shallow marine sediments from Jinzhou Bay, China
.
Journal of Environmental Sciences
22
,
23
31
.
WHO
2011
Guideline for Drinking Water Quality
,
4th edn
.
World Health Organization
,
Geneva
.
Zaki
R.
Ismail
E. A.
Mohamed
W. S.
Ali
A. K.
2015
Impact of surface water and groundwater pollutions on irrigated soil, El Minia Province, northern Upper Egypt
.
Journal of Water Resource and Protection
7
,
1467
1472
.
Zakir
H. M.
Rahman
M. M.
Rahman
A.
Ahmed
I.
Hossain
M. A.
2012
Heavy metals and major ionic pollution assessment in waters of midstream of the River Karatoa in Bangladesh
.
Journal of Environmental Science and Natural Resources
5
(
2
),
149
160
.
Zeitoun
M. M.
Mehana
E. E.
2014
Impact of water pollution with heavy metals on fish health: overview and updates
.
Global Veterinaria
12
(
2
),
219
231
.