MANOVA Statistical Analysis of Inorganic Compounds in Groundwater Indonesia

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IOSR Journal of Environmental Science, Toxicology and Food Technology (IOSR-JESTFT) e-issn: 2319-2402,p- ISSN: 2319-2399.Volume 8, Issue 4 Ver. I (Apr. 2014), PP 41-45 MANOVA Statistical Analysis of Inorganic Compounds in Groundwater Indonesia Heruna Tanty 1, Rokhana Dwi Bekti 2, Tati Herlina 3, Nurlelasari 4 1,2 Department of Mathematics and Statistic, 3,4 Department of Chemistry 1,2 School of Computer Science, Bina Nusantara University 3,4 University of Padjadjaran Abstract: The present study was carried out to determination a levels of inorganic compounds contained in the ground water and Reverse Osmosis (RO) water result. The data in groundwater samples was collected from Bekasi, Tangerang and Jakarta in Indonesia. A total of 30 samples were collected and analyzed for the determination of Cadmium (Cd), Chromium (Cr), Manganese (Mn), Cyanide (CN) and Lead (Pb). The results of the study revealed that in groundwater, the average of Cd 0.0058 mg / l, Mn 1.5233 mg / l, Cr 0.0127 mg/l, Pb 0.0060 mg / l, and CN 0.0040 mg / l. The level of RO result were: Cd 0.0027 mg / l, Mn 0.1767 mg / l, Cr 0.0024 mg / l, Pb 0.0021 mg / l, and CN 0.0023 mg / l. It s mean that Cd and Mn in ground water were higher than the values recommended by PAK-EPA and WHO or the standard of Indonesian Ministry of Health. But after Reverse Osmosis (RO) Mn and Cd levels decreased to levels below the standardized value. By comparing of mean in MANOVA and nonparametric MANOVA in α=5%, there are differences in average levels of inorganic substances Mn, Cr, Cd, Pb, and CN between before and after RO. Keywords: Inorganic Compounds, G, Reserve Osmosis, MANOVA PACS: 07.89.+b, 02.50.Sk I. Introduction Water is essential for human life. Functions of water in the body are cell life, chemical and metabolic reaction, transform of nutrients, body temperature regulation and elimination of waste [1]. Jakarta, Bekasi and Tangerang are a large region population in Indonesia. Water needs in these three areas is very high, but the local water company (PDAM) in Jakarta can only supply 39% of the population water needs. Most people use water refills. Some of them consume Reverse Osmosis (RO) water result, but many low-income peoples directly consume groundwater for drinking. Jakarta, Bekasi and Tangerang have many industries and densely populated residential. Increase in the number of septic tanks polluting the groundwater and can have serious health effects diseases such as hepatitis and dysentery. Inorganic compounds such as Chrome (Cr) reduces fatty acids and cholesterol and regulates sugar and insulin rates in the blood, but chronic exposure to high chromium levels causes lung cancer in human [2]. Groundwater for drinking has the potential to cause damage to liver, kidney, circulatory and nerve tissues and skin irritation from long-term exposures at levels above the Maximum Contaminant Level (MCL) [3]. Heavy metal toxicity like Lead (Pb), Cadmium (Cd), Manganese (Mn) are can result in damaged or reduced mental and central nervous function, cancer, lower energy levels, and damage to blood composition, lungs, kidneys, liver, and other vital organs [4]. Therefore, the study of inorganic compounds in the groundwater and water Reverse Osmosis (RO) result was done. There are some statistical methods for analysis the water quality, such as Multivariate Analysis of Variance (MANOVA) [5], [6]. Function of MANOVA is comparison of dependent variable means across multiple groups. It requires that the observations are independent, the response variables are multivariate normally distributed, and the covariance matrix of the dependent variables is homogeneous across groups. This research use MANOVA to compare inorganic compounds in the ground water and RO. The results of MANOVA can determine the effect of RO in water quality, and the differentiation of quality water in groundwater and RO. When assumption of MANOVA, homogeneity variance or normal distribution, was violated, then it can use nonparametric MANOVA [7], [8]. II. Methodology Sampling For the present investigation, there were 30 groundwater samples collected from different localities of Bekasi, Tangerang and Jakarta in Indonesia. The time of data collecting was during the months of May to August 2013. The samples were in screw high density polyethylene bottles. The sample bottles were rinsed 41 Page

twice with the sample water to avoid any impurity. It also labeled properly and immediately transferred to laboratory in Padjadjaran University in Bandung-Indonesia. Determination Of Lead (Pb) And Cadmium (Cd) Fifty ml of the test sample was inserted into beaker of 100 ml or 100 ml Erlenmeyer and add 5 ml of HNO 3 concentrated. It closed with watch glass then heated slowly until the residual volume of 15 ml - 20 ml. If destruction is not perfect (not clear), then added 5 ml of HNO 3 dense and closed with a watch glass and then heated again (do not boil). This process was done repeated until all dissolved metals, which looks sample of sediment color became somewhat white or test sample becomes clear. After the glass watch water was rinsed, put solute in the beaker. Then the test sample transferred into a 50 ml volumetric flask (filtered if necessary) and added demineralized water tera sign up right then homogenized. After the absorbance read at using AAS instrument [9], [10]. Determination Of Chrome (Cr) Pipette a volume (V) of test sample and place in a 100 ml beaker, add 0.25 ml (5 drops) H 3 PO 4, adjust to ph 2.0 ± 0.5 by addition 0.2 N sulfuric acid. Move the sample solution into 100.0 ml volumetric flask. For specify the calibration mark with demineralized water, add 2.0 ml of solution difenilkarbazida, shake and let stand 5 to 10 minutes; measuring absorbance at a wavelength of 530 nm or 540 nm; record the measurement results [11]. Determination Of Manganese (Mn) Include 100 ml sample that has been whipped up into a homogeneous beaker, add 5 ml HNMO 3, and heat in an electric heater until the solution sample dry. Then added 50 ml of distilled water, put into a flask of 100 filter paper and matched ml through 100 ml with distilled water [12]. Determination Of Cyanide (CN) Pipette 10 ml of standard solution of cyanide (± 1000 mg / l) to the Erlenmeyer (Duplo) and dilute with a solution of 0.04 M NaOH diluents by the volume of ± 100 ml which use a blank 0.04 M NaOH solution. After that, add 1 ml of indicator solution rodamina and do homogeneous process. Titar with standard-agno 3 solution until the color changes from clear yellow first red-brown, and chartreuse. Note that the volume of AgNO 3 standard solution worn on of Cianide (CN)[13]. III. Data Analysis For analyze the research data, do the following steps: 1. Conduct descriptive analysis covers the average, standard deviation, minimum value and maximum value for Pb, Cd, Cr, Mn, and CN. [14] 2. MANOVA test using test Pillai's Trace, WilksLamda, Hotelling's Trace and Roy's Largest Root. The goal is to test whether there are differences in the average levels of inorganic compounds in groundwater samples and samples of RO at α 5% [14] The MANOVA assumption were the data is multivariate normal distribution and variance matrix is homogeny. The assumption tests used were Shapiro Wilk Normality test and Box's M [15]. If these assumptions were violated, it uses nonparametric MANOVA. MANOVA with one factor have the model [14], x ijk k ik ijk (1) Where, x = the dependent variable μ = the mean of x τ = factor effect/treatment ε = error i = level of effect, i =1,2, j = the replication, j=1,2, k = number of dependent variable The significant test uses the F and P value from the results of MANOVA table. Reject Ho if F>F (df1,df2,α) or P value < α. 42 Page

In this research the dependent variable was Mn, Cr, Cd, Pb, and CN. The factor was type of water, consist of 2 levels: ground water and water after RO. IV. Results And Discussion The analysis in this study include descriptive analysis, test for normality, homogeneity testing, and Multivariate Analysis of Variance (MANOVA) for inorganic substances Mn, Cr, Cd, Pb, and CN in the ground water. Levels of these substances were divided into two groups based on water samples, i.e. the samples of raw water (control) or ground water and the results of water by Reserve Osmosis (RO). TABLE 1. Characteristics of Chromium (Cr) G 0,0127 0,0051 0,0030 0,0180 R 0,0024 0,0030-0,0060 0,0090 From the Table 1, it can be seen that the average levels of substance Chromium (Cr) after in RO was lower than in ground water. It was 0.0127 mg/l in ground water and 0.0024 mg/l in RO. Cr levels in the Ground water and RO results still eligible of the values recommended by PAK-EPA and WHO [16] or the standard of Indonesian Ministry of Health 0.05 mg /l. TABLE 2. Characteristics of Manganese (Mn) G 1,5233 0,4717 1,000 3,500 R 0,1767 0,1194 0,000 0,300 The average levels of substance Manganese (Mn) RO results lower than in groundwater (see Table 2). Mn levels in the ground water still higher than the values recommended by PAK-EPA and WHO or the standard of Indonesian Ministry of Health 0,5 mg/l. It was perform that quality of Mn in ground water was poor. Otherwise, R results still eligible of the values recommend. TABLE 3. Characteristics of Cadmium (Cd) G 0,0058 0,0007 0,0050 0,0070 R 0,0027 0,0012 0,0010 0,0050 Such as Mn, the average level of Cadmium (Cd) in RO was lower than in groundwater (see Table 3). Cd levels in the ground water still higher than the values recommended by PAK-EPA and WHO or the standard of Indonesian Ministry of Health 0.003 mg/l, but in R was still eligible. TABLE 4. Characteristics of Lead (Pb) G 0,0060 0,0030 0,0040 0,0090 R 0,0021 0,0009 0,0010 0,0030 Lead (Pb) in ground water was 0.0060 mg/l and in RO was 0.0021 mg/l (see Table 4). Average of Pb in RO was lower than in groundwater. But all of them still eligible of the values recommended by PAK-EPA and WHO or the standard of Indonesian Ministry of Health 0.01 mg /l. As well as for Cyanide (CN), the average in RO was lower than in groundwater. But all of them still eligible of 0.007 mg /l (see Table 5). 43 Page

TABLE 5. Characteristics of Cyanide (CN). G 0,0040 0,0008 0,0030 0,0050 R 0,0023 0,0008 0,0010 0,0040 Multivariate Normality Test Before conduct the MANOVA analysis, it performed the multivariate normal assumption. The hypothesis used is as follows: H 0 : The data follow a normal distribution multivariate distribution. H 1 : The data do not follow the distribution of a multivariate normal distribution. Shapiro-Wilk normality test data: Z W = 0.8345, p-value = 1.095e-06 FIGURE 1. Output of Multivariate Normality Test It was use Shapiro Wilk test in R. From the results, it can be seen that Pvalue is 0.07247 (see Figure 1). It was less than α = 5%, so the data content of Mn, Cr, Cb, Pb, and CN were not follow a multivariate normal distribution. So the MANOVA assumption was violated. Multivariate Homogeny Test The second assumption of MANOVA analysis is homogeneity of variant of covariance matrix. This study use Box's M to test the homogeneity. Hypotheses used are: H 0 : variance covariance matrix homogeneous H 1 : variance covariance matrix is not homogeneous TABLE 6. Box s M Test Box s M P value 7,344 0,000 The test results by SPSS are presented in Table 6. The conclusion is reject Ho or variance covariance matrix is not homogeneous. So, the MANOVA assumption was violated. This is indicated by the value P value = 0.000 which less than α = 5%. Manova MANOVA test was done through test Pillai's Trace, Wilks' Lambda, Hotelling's Trace, and Roy's Largest Root. The hypothesis used is H 0 : There is no difference in the average levels of inorganic substances Mn, Cr, Cd, Pb, and CN H 1 : There are differences in average levels of inorganic substances Mn, Cr, Cd, Pb, and CN Decision making is the reject Ho if the P value less than α. The test results showed that the value of P value on all testing is less than α = 5%. So the conclusion is that Ho rejected or there are differences in average levels of inorganic substances Mn, Cr, Cd, Pb, and CN between before and after RO. TABLE 7. MANOVA Test Effect Value F df 1 df 2 P value Intercept Pillai's Trace 0,999 8065 5,000 54,000 0,000 Wilks' Lambda 0,001 8065 5,000 54,000 0,000 Hotelling's Trace 746,753 8065 5,000 54,000 0,000 Roy's Largest Root 746,753 8065 5,000 54,000 0,000 Treatment Pillai's Trace 0,938 164 5,000 54,000 0,000 Wilks' Lambda 0,062 164 5,000 54,000 0,000 Hotelling's Trace 15,169 164 5,000 54,000 0,000 Roy's Largest Root 15,169 164 5,000 54,000 0,000 44 Page

Nonparametric MANOVA In the MANOVA analysis discussed above, it can be seen that the assumption of normal distribution and homogeneity were not met. Therefore, a comparison analysis was done using a nonparametric MANOVA. Output analysis is presented in Table 8. These results indicate that the value of P value less than 0.001 α = 5%. So the conclusion is that Ho rejected or there are differences in average levels of inorganic substances Mn, Cr, Cd, Pb, and CN between before and after RO. It was also performs that RO can be use to get a better water quality in Bekasi, Tangerang, and Jakarta, Indonesia. TABLE 8. Nonparametric MANOVA Test Source df SS MS F P value Water 1 6,6388 6,6388 67,512 0,001 Residual 58 5,7034 0,0983 Total 59 12,3422 V. Conclusion From the results of laboratory tests indicate that the groundwater in the area of Bekasi, Tangerang and Jakarta (Indonesia) levels of manganese (Mn) and Cadmium (Cd) above are standardized by the PAK- EPA, WHO or the Indonesian Ministry of Health. But after Reverse Osmosis (RO) Mn and Cd levels decreased to levels below the standardized by PAK- EPA, WHO and Indonesia Ministry of Health. Generally, all the inorganic compounds in ground water and RO were difference. The average in RO was less than in ground water. It was supported by MANOVA analysis. In α=5%, it conclude that there are differences in average levels of inorganic substances Mn, Cr, Cd, Pb, and CN between before (ground water) and after RO. Anknowledgment Thanks to the Directorate General of Higher Education, Ministry of Education of the Republic of Indonesia and rector of Bina Nusantara University, Jakarta Indonesia References [1]. Nestle Waters, 5 water functions in human body, http://www.nestle-waters.com/healthy-hydration/water-fonctions-in-humanbody#cell (Accessed on 10 April, 2013), 2013. [2]. A. V. Wiesenberger, The Influence of Minerals in Water. Excerpted from The Taste of Water, 2001. [3]. Hexavalent Chrome Contamination Treatment for Public Drinking Water Supply.http://www.water.siemens.com/en/applications/groundwater_remediation/Pages/IPW_ace_services_colby_kansas_ca.aspx [4]. EPA, Basic Information about Cadmium in Drinking Water. http://water.epa.gov/drink/ contaminants/basicinformation/cadmium.cfm (Acessed on 10 April, 2013), 2013. [5]. K.E. McCluney and R.C. Date, The effects of hydration on growth of the house cricket, Acheta domesticus, Journal of Insect Science, 2008, 8 (32), available online: insectscience.org/8.32 [6]. A.Z. Garizi, V. Sheikh, and A. Sadoddin, Assessment of seasonal variations of chemical characteristics in surface water using multivariate statistical methods. International Journal of Environmental Science and Technology, 2011, 8(3), pp. 581-592. [7]. HE, Fanyin. Nonparametric MANOVA Approaches for Non-Normal Multivariate Outcomes. 2013. PhD Thesis. University of Pittsburgh. [8]. H. Finch, Comparison of the performance of nonparametric and parametric MANOVA test statistics when assumptions are violated. Methodology: European Journal of Research Methods for the Behavioral and Social Sciences, 2005, 1(1), pp. 27-38. [9]. BSN, Water and waste water - Part 8: Test methods for lead (Pb) in Atomic Absorption Spectrophotometry (AAS)-flame, SNI 6989.8:2009, Jakarta : BSN, 2009. [10]. BSN, Water and waste water - Part 16: Test method for cadmium (Cd) in Atomic Absorption Spectrophotometry (AAS)-flame, SNI 6989.16:2009, Jakarta: BSN, 2009. [11]. BPPK, Hexavalent Chromium Test Method 6989.71:2009, http://intranet.bbpk.go.id/pesan/files /35117SNI%206989_17%20(krom%20heksavalen).pdf (Accessed on 20 September, 2013), 2009. [12]. BSN, SNI-water and waste water-part 5, SNI 06-6989.5, Jakarta: BSN, 2004. [13]. BSN, Test Botteld Water, SNI 01-3554-2006, Jakarta : BSN, 2006. [14]. R. A. Johnson and D. W. Wichern, Applied Multivariate Statistical Analysis, 5th Edition, New Jersey : Prentice Hall, Engelwood Cliffs, 2002. [15]. D.C. Montgomery, Design and Analysis Of Experiments, 6th Edition, Arizona : John Wiley and Sons, 2005. [16]. Lenntech, WHO's drinking water standards 1993.http://www.lenntech.com/applications/drinking/standards/who-s-drinking-waterstandards.htm (Accessed on 20 April, 2013), 2013. 45 Page