Available online at www.worldscientificnews.com WSN 24 (2015) 56-60 EISSN 2392-2192 ph, hardness and elemental profile if rain water (zinc roofing sheet vs open air collection) M. Fadilu 1, M. K. Atiku 2, M. M. Barau 1, M. A. Abubakar 1, K. Salahu 1, A. I. Ibrahim 2, T. A. Owolorafe 1, T. A. Lawal 1 1 Department of Biochemistry/Forensic Science, Faculty of Science, Nigeria Police Academy Wudil, P.M.B 3474 Kano, Nigeria 2 Department of Biochemistry, Faculty of Biomedical Sciences, Bayero University Kano, P.M.B 3011 Kano, Nigeria ABSTRACT Drinking water is one of the basic needs of life and essential for survival of all living things. Elemental profile, ph and hardness of rain water collected under zinc roofing sheet and open air was determined. The rain water was collected in the month of July and August in Kano metropolis. The results reveals that rain water contains elements such as lead, zinc, copper, chromium, nickel, manganese, sodium, potassium and magnesium which were determined using Atomic Absorption Spectroscopy. The ph values of the samples ranges from 5.6-6.9 with a mean ph of rain water collected under zinc roofing sheet of 6.25 ±0.39 and that of water collected in open air space of 6.49 ±0.26 which shows that there was no significant difference (p < 0.05) for the two methods used. Measurements of total hardness shows that, rain water was slightly hard with significant difference (p < 0.05) for the two methods of collection used. Keywords: ph; hardness; elemental profile; rain water and zinc roofing sheet 1. INTRODUCTION Water is one of necessity of life and form bulk of the living cell. Rain water is defined as precipitation that falls from clouds but usually the rain that falls over ground is tested
because rain over ocean is less concern to scientist. The resources of usable water had been diminishing and are unable to meet the varieties of need of modern civilization. Most individuals in rural areas collect rain water for domestic use, such as drinking, cooking and other domestic activities. They tend to collect rain water from roofing sheet such as asbestos and zinc. This water collected under zinc sheet may contain trace amount of heavy metals. Heavy metals refer to any metallic element that has a relatively high density and is toxic or poisonous even at low concentration (Leentech, 2004). Heavy metals/ metalloids include lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As), chromium (Cr), copper (Cu), selenium (Se), nickel (Ni), silver (Ag) and zinc (Zn). Other less common metallic contaminant include aluminium (Al), cesium (Cs), cobalt (Co), manganese (Mn), molybdonum (Mo), strontium (Sr), and uranium (U) (Mcintyre, 2003). The main natural sources of metals in water are chemical weathering of minerals on soil leaching. Other sources mainly include industrial and domestic effluents, urban storm, water run off, landfill, atmospheric sources and inputs rural areas (El Bouraie et al., 2010). Heavy metals like lead and zinc in high concentration are of serious concern to human health because they are known to constitute highly persistent environmental pollutant (Mc Aloon and Mason, 2003) and their ability to accumulate in aquatic ecosystem (shrivastava, 2011). Heavy metals disrupt metabolic function in two ways. They accumulate and thereby disrupt function of vital organs and glands like heart and liver and they displace the vital nutritional minerals from their original place, there by hindering their biological function (Singh, 2007). Physicochemical parameters of any water play a very important role in maintaining the fragile ecosystem that maintains various life forms. ph is the measure of acidic or basic nature of a solution. The concentration of the hydrogen ions [H + ] activity in a solution determines the ph. The ph value is the negative power to which 10 must be raised to equal the hydrogen concentration (Manoj and Avinash, 2012). Water can combine with the various compounds in the atmosphere before it falls as rain. Hardness of water is the measure of capacity of water to precipitate soap. Total hardness is defined as the sum of calcium and magnesium concentrations in water (Manoj and Avinash, 2012). The aims and objectives of this research work is; 1. To determine the ph and hardness of rain water collected under zinc roofing sheet and open air space. 2. To find the elemental profile of rain water and identify the likelihood of heavy metals in it. 2. MATERIALS AND METHODS Sample collection Rain water samples were collected in Kano metropolis in the month of July and August. A total of twenty collection of rain water were made. Ten under corrugated zinc roofing sheet while other ten under open air space. The samples were carefully transferred in to a clean plastic containers rinsed four times with the water samples and labeled indicating the date and time of collection. The samples were immediately transferred to the laboratory stored at room temperature and analyzed within a week of collection. -57-
Sample analysis Each water sample was analyzed for determination of ph (APHA, 1998), total hardness by EDTA titrimetric method described by Owoso et al.,(2000) and metals were analyzed by atomic absorption spectroscopy described by the American Society for Testing Materials (ASTM, 2002). Statistical analysis Student s t test was used for statistical analysis. 3. RESULTS AND DISCUSSION Table 1 presents the results of mean concentration of elements under corrugated zinc roofing sheet and the mean concentration of elements under open air space. Table 2 presents the ph of water collected under zinc roofing sheet and the water collected under open air space with their mean and standard deviation. Table 3 presents total hardness of water collected under zinc roofing sheet and the water collected under open air space with their mean and standard deviation. Table 1. Concentration of elements under corrugated zinc sheet and under open air space (ppm). Element under corrugated zinc sheet under open air space Pb 0.98 ± 0.07 0.220 ± 0.125 Zn 0.010 ± 0.095 0.110 ± 0.04 Cu 0.445 ± 0.102 0.0318 ± 0.018 Cr 0.254 ± 0.022 0.223 ± 0.031 Ni 0.736 ± 0.027 0.302 ± 0.004 Mn 0.270 ± 0.033 0.305 ± 0.011 Na 0.370 ± 0.012 0.454 ± 0.211 K 2.679 ± 0.326 0.130 ± 0.008 Mg 1.895 ± 0.114 0.130 ± 0.001 Results are mean ± standard deviation. -58-
Table 2. ph of water under corrugated zinc sheet and under open air space. S/N 1 2 3 4 5 6 7 8 9 10 Zinc sheet Open air Mean ± standard deviation 6.5 6.7 6.0 6.3 5.9 6.1 6.8 6.6 5.6 6.0 6.25 ±0.39 6.4 6.2 6.9 6.7 6.3 6.6 6.1 6.5 6.8 6.4 6.49 ±0.26 Table 3. Total hardness of water under corrugated zinc sheet and under open air space. S/N 1 2 3 4 5 6 7 8 9 10 Zinc sheet Open air Mean + standard deviation 17.2 18.8 16.0 16.8 20.4 21.6 19.6 18.8 19.2 20.0 18.84 ±1.73 22.4 21.6 21.2 20.0 22.8 2.6 19.2 18.4 23.2 22.0 21.24 ±1.56 4. DISCUSSION The mean ph of rain water collected under zinc roofing sheet was found to be 6.255 ± 0.39 while that of water collected in open space was 6.49 ±0.26 which shows that there was no significant difference (p < 0.05) in ph for both methods of collection. This result is slightly below WHO permissible limits of drinking water. The mean total hardness concentration of water under corrugated zinc sheet was found to be 18.84 ±1.73 while that collected under open space was 21.24 ±1.56 and the values were found to be within the WHO permissible limits. The mean chromium, manganese and lead concentration of water samples collected under zinc roofing sheet were found to be 0.254 ppm, 0.270 ppm and 0.98 ppm respectively while those collected under open space was 0.223 ppm, 0.305 ppm and 0.220 ppm respectively. These values were above the WHO permissible limit. The mean zinc, copper, sodium, potassium and magnesium concentration of water samples collected under zinc roofing sheet were found to be 0.010 ppm, 0.445 ppm, 0.370 ppm, 2.679 ppm and 1.895 ppm respectively while those collected under open space were 0.110 ppm,0.318 ppm, 0.454 ppm, 0.130 ppm and 0.130 ppm respectively. These values were within the WHO permissible limit. The differences obtained between the two methods of collection may be due to wash off from particles and from other sources. 5. CONCLUSION From the results obtained it can be concluded that the ph and hardness of rain water were satisfactory but it contain heavy metals in various concentrations and most of them were -59-
above the who permissible limits of drinking water which may lead to bioaccumulation of these metals in human and causes biotoxicity. The metal concentration of most samples collected under zinc sheet were higher this may be due to the property of zinc sheet or as a result of wash off from the roofing sheet or different concentration of various rain. It is recommended that heavy metals analysis should be included as part of the routine analysis in the laboratory. References [1] APHA (American Public Health Association) (1998). Standard Method for Determination of Water and Wastewater. 20 th edn. New York 1: 839-410 [2] American Society for Testing Materials (2002). Annual Book of ASTM Standard section 11-Water and environmental technology. Vol. 11-01 water (1) PHiladelphia. Pp 801-823 [3] El Bouraie, M. M., El Barbary, A. A., Yehia, M. M. and Motawea, E. A. (2010): Heavy Metal Concentrations in Surface River Water and Bed Sediments at Nile Deltain Egypt. Suoseura Finish Peatland Society, Helsinki. Vol. 61(1), pp. 1-12. [4] Lenntech Water Treatment and Air Purification (2004). Water Treatment published by Lenntech, Rotterdamseweg. Netherlands. (www.excelwater.com/thp/filters/waterpurification.htm). [5] Manoj Kumar and Avinash Puri (2012). A Review of Permissible Limits of Drinking Water. Indian J Occup Environ Med 16(1), 40-44. [6] McAloon, K. M. and Manson, R. P. (2003): Investigation into the Bioavailability and Bioaccumulation of Mercury and other Trace Metals to the Sea Cucumber, Sclerodactylabaria rens, using invitro solubilization. Marine Pollution Bulletin. 46, 1600-1608. [7] Mcintyre T. (2003). Pytoremediation of Heavy Metals from Soil. Adv Biochem Eng Biotechnol. 78: 97-123 [8] Owoso, O.F., Aluko, O. and Banjoko, O.I. (2000). Manual of Food Analysis and Quality Control. Concept Publication. Pp. 41-58. [9] Shrivastava, V. S., Sen, I. and Shandil, A. (2011). Study for Determination of Heavy Metals in Fish S. [10] pecies of the River Yamuna (Delhi) by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). Advances in Applied Science Research. 2(2), 161-166. [11] Singh MR (2007). Impurities- Heavy Metals. IR prespective. http://www.usp.org/pdf/en/meetings/as meatingmedia/2008session4track1.pdf. ( Received 08 October 2015; accepted 22 October 2015 ) -60-