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Procedia - Social and Behavioral Sciences 222 ( 2016 ) 263 – 271

ASLI QoL2015, Annual Serial Landmark International Conferences on Quality of Life ASEAN-Turkey ASLI QoL2015 AicQoL2015Jakarta, Indonesia. AMER International Conference on Quality of Life The Akmani Hotel, Jakarta, Indonesia, 25-27 April 2015 “Quality of Life in the Built & Natural Environment 3"

Leachate and Surface Water Characterization and Heavy Metal Health Risk on Cockles in Kuala Selangor

Ahmad Razali Ishaka,b*, Sharifah Mohamadb, Tey Kheng Soob, Fauziah Shahul Hamidb

aDepartment of Environmental Health, Faculty of Health Sciences, UiTM Puncak Alam, 42300 Kuala Selangor, Malaysia bChemistry Department, Faculty of Sciences, Universiti Malaya, 50603 Kuala Lumpur, Malaysia

Abstract

Characterization of physicochemical parameters including of in , surface water and cockles (Anadara granosa) were analyzed in Kuala Selangor, Malaysia. The effects of location and seasonal variation of surface water and cockles were determined. In addition, the target hazard quotients (THQ) were calculated to determine the potential health risk. Heavy metals were analyzed by ICP-MS and the result were compared with the national permissible limit. There was a little variation in heavy metal concentration between location and season for surface water and cockles samples. THQ value was found lower for all heavy metal and shows no potential risk. © 20162015 The The Authors. Authors. Published Published by byElsevier Elsevier Ltd. Ltd This. is an open access article under the CC BY-NC-ND license (Peerhttp://creativecommons.org/licenses/by-nc-nd/4.0/-review under responsibility ofAMER (Association). of Malaysian Environment-Behaviour Researchers) and cE-Bs (Centre Peerfor Environment-review under- Behaviourresponsibility Studies, of AMER Faculty (Association of Architecture, of Malaysian Planning Environment-Behaviour & Surveying, Universiti Researchers) Teknologi and cE-Bs MARA, (Centre Malaysia for . Environment- Behaviour Studies, Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia. Keywords:Leachate; surface water; Anadara granosa; health risk

* Corresponding author. Tel.: +0-000-000-0000 ; fax: +0-000-000-0000 . E-mail address: [email protected]

1877-0428 © 2016 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers) and cE-Bs (Centre for Environment- Behaviour Studies, Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia. doi: 10.1016/j.sbspro.2016.05.156 264 Ahmad Razali Ishak et al. / Procedia - Social and Behavioral Sciences 222 ( 2016 ) 263 – 271

1. Introduction

The world is facing the largest trend of urban growth in history. More than 50% of the world's population nowadays are living in the cities, and the number will keep expanding to almost 5 billion by the year of 2030 (United Nations Population Fund, 2011). In economic point of view, creating more cities will generate more job opportunities and eventually higher economy level will follow. Therefore, this phenomenon challenges governance and authority in providing infrastructure, transportation system, food and ultimately the management of solid . Evaluation of the urban system such as by using economic input output analysis could observe those resulting impacts because the resulting impact of a city system are not always immediate and direct (Shafie et al, 2013). Urban society tends to produce the high volume of solid waste from a variety of sources including from domestic, commercial and institutional . process directly contributes to waste generation and unscientific waste handling causes health hazards and urban environment degradation (Dimpal, 2012). Heavy metals have been suggested to disturb biochemical mechanisms and prone to bio accumulate in the ecosystem (Fairus et al., 2011). Food consumption has been identified as the major pathway of human exposure, accounting for more than 90% of the exposure compared to other ways of exposure such as inhalation and dermal contact (Loutfy et al., 2006). A number of studies have shown the tendency of heavy metals in water and food to accumulate in human body either by ingestion or via dermal contact absorption (Alkarkhi et al.; 2008, Luis et al.; 2013, Etelvina et al.; 2011, Khan et al., 2008). The working concept of this study was to characterize physicochemical parameters in raw leachate from Jeram Sanitary Landfill (JSL), surface water in the upstream and downstream of Sungai Sembilang and the level of heavy metal in the cockles collected from Jeram beach. The potential health risk was also calculated to determine whether any likelihood of cockle consumption to the surrounding population was present.

2. Methodology

2.1. Sampling location

Fig.1. The details of sampling point

Jeram landfill is one of the sanitary in Malaysia. It is located in Kuala Selangor District and was opened in January 2007 with estimated disposal capacity of 8.5 million tonnes. This landfill has replaced Air Hitam Sanitary landfill that was closed in December 2006. It is equipped with leachate treatment facility including Sequential Batch Ahmad Razali Ishak et al. / Procedia - Social and Behavioral Sciences 222 ( 2016 ) 263 – 271 265

Reactor (SBR), Dissolved Air Floatation (DAF) system, sand and activated filter in order to prevent the potential contaminant from seeping out to the adjacent environment. The treated leachate of JSL was discharge into Sungai Sembilang and the finally end up in the coastal area of Jeram Beach where the cockle farm agricultural industry is in place. Raw leachate was collected directly from the leachate discharge pipe before entering the first holding pond while the surface water of Sungai Sembilang was taken at the 0.5 km upstream and downstream region of JSL. The cockles were sampled from the Pantai Jeram cockle’s farm that is located approximately 8 kilometers from JSL. The details of the sampling point were illustrated in Fig. 1.

2.2. Field sampling

Three samples of raw were collected from JSL at different times starting from July 2014 until December 2014. For surface water, a total of 12 samples were collected from two separate locations (6 samples at the upstream and another six samples from the downstream region). As for cockles, 18 samples were collected from three different cockles’ farms. The similar cockle’s length (30-50 mm) were obtained to minimize variation in age and accumulation of any contaminant between individuals. A number of 9 samples were taken during dry season and another 9 samples were collected during wet season. The details of the sampling point and date are as in Table 1. All the five physical parameters (pH, , , conductivity and total dissolved solid) for leachate and surface water were measured in situ at the sampling point by using multiparameter probe (Hanna HI 8424). BOD and COD of leachate were analyzed by using APHA Standard method (APHA 2008). Leachate and surface water samples were collected into the 1 liter polyethylene sample bottles. The samples were acidified with a few drops of 5% nitric acid to prevent the probability of heavy metal . As for cockle’s samples, the soft – body tissue was separated from the shell and immediately rinsed with ultrapure water and transferred to container. All the samples were stored at 4°C until subsequent metal analysis.

Table 1. Summary of sampling point and dates of sampling

Sampling Point Label Sampling coordinate Sampling dates 1 Raw leachate R 3°11’34.00”N,101°21’53.96”E 12/11/2014, 18/12/2014, 27/11/2014 2 Surface Water S1 3°11’37.48”N,101°22’ 9.69”E 27/11/2014, S2 3°11’38.10”N,101°21’37.08”E 8/12/2014, 18/12/2014, 3 Cockles C1 3°10’35.91”N,101°17’12.26”E 9/7/2014, 18/7/2014, C2 3°11’14.35”N,101°16’51.09”E 30/7/2014 C3 3°11’55.80”N,101°16’18.57”E

2.3. Sample treatment and analysis

Leachate and surface water samples were filtered twice by using Whatman 0.45-mm filter paper. The surface water sample was then transferred into 50 ml polypropylene tube and were kept at 4ͼC until analysis. Raw leachate samples were diluted ten times before transferred into 50 ml polypropylene tube. The modified method from Etelvina et al., (2011) had been adopted for cockles. 25 g of soft tissue were digested overnight at 1150C in 4 ml high purity nitric acid. The cooled digest was diluted to 5ml using 1M nitric acid (HNO3) and then filtered through a 0.45-mm cellulose filter (Whatman) into 100ml polypropylene tube for heavy metal analysis. A total of 9 heavy metals were analysed by using inductively coupled plasma mass spectrometry (ICP-MS). Multi-element standard were used to prepare the calibration curve and the calibration curves with R2 > 0.999 were accepted for concentration calculation. 266 Ahmad Razali Ishak et al. / Procedia - Social and Behavioral Sciences 222 ( 2016 ) 263 – 271

2.4. Health risk assessment

In this study, potential health risk of cockles consumption was determined by using USEPA risk assessment method (USEPA, 2000) and modified method from Chien et al. (2002). Average daily dose (ADD) was calculated by using the formula in the equation one who express the average daily intake of particularly heavy metal over a specified period.

Where; EF = exposure frequency (365 days/year) ED = Exposure duration of average lifetimes (70 years) (Bennett et al., 1999) FIR = Food ingestion rate (g/day) Peninsular: 4.92, Malay: 5.36, Chinese: 3.10, Indian: 3.61 (Ministry of Health Malaysia 2003). C = metal concentration in food (mg/kg) RfD = oral reference dose (mg/kg/day) WAB = average body weight (55.9 kg for adults and 32.7 kg for children) TA = averaging exposure time for non-carcinogens (365 days/year number of exposure years, assuming 70 years in this study: 25550 days).

The results of ADD is then divided with a reference dose (RfD) provided by USEPA for determination of target hazard quotient (THQ) which represent non-carcinogenic risk level to the population. The formula for calculation of THQ was described in equation 2. If the value of THQ is less than one, it is accepted that there is no significant risk of non-carcinogenic effects. If the THQ exceeds one, then there is a chance that non-carcinogenic effects may occur, with a probability that tends to increase as the value of HQ increases (USEPA, 2000).

3. Result and discussion

3.1. Leachate characterization

Table 2 shows the physicochemical properties including heavy metal in the raw leachate collected from JSL. From the total of 17 parameters, 7 parameters (BOD, COD, Fe, Cr, Ni, Zn, As) were beyond the standard limit allowed by the Environmental Quality (Control of from Solid Waste Transfer Station and Landfill) Regulations 2009. The relatively high BOD(270 mg/L) and COD(4637 mg/L) concentration indicates high organic strength in the landfill leachate. However, the result of BOD and COD were far lower than the earlier finding from Emineke et al. (2011) from the same landfill. This result might be due to the different of sampling locations. In this study, the raw leachate samples were not obtained from the holding pond but collected from the leachate pipe that is connected directly from the landfill dumpsite. These fresh leachates were at the early stages and has not undergone the stabilization phase. The black coloration of raw leachate and high concentration of total dissolved solid (TDS) (6566 mg/L) suggested the presence of high suspended matter and high dissolved organic matters in the waste . Besides, the moderately high concentration of ferum (Fe) (7.3 mg/L) indicates the presence of steel scrap dumped at the JSL. The oxidation of ferrous to a ferric form and the formation of ferric hydroxide and complexes with humic substances is the another reason of the black coloration of leachate (Chu et al., 1994). The existence of Zn (3.27 mg/L) in the leachate indicates the presence of waste from batteries and fluorescent lamps.

Ahmad Razali Ishak et al. / Procedia - Social and Behavioral Sciences 222 ( 2016 ) 263 – 271 267

Table 2. Physical-chemical analysis of raw leachate from Jeram Sanitary Landfill

Parameters Unit Quantity Standard limits Colour NA Black NA pH NA 8.1 6.0 – 9.0 Temperature ͼC 37 40 Turbidity NTU 155 NA Conductivity 12.4 NA TDS Mg/L 6566 NA BOD Mg/L 270 20 COD Mg/L 4637 400 Cr Mg/L 0.65 0.05 Fe Mg/L 7.3 5.0 Ni Mg/L 0.32 0.20 Zn Mg/L 3.27 2.00 As Mg/L 0.67 0.05 Cd Mg/L 0.03 0.01 Pb Mg/L 0.03 0.10 Cu Mg/L 0.01 0.20 Mn Mg/L 0.04 0.20

NA = Not available

3.2. Surface water analysis

The contamination of heavy metal in an aquatic ecosystem may accumulate in the food chain and cause serious harm to human health where contamination content and exposure are significant (Fernandes et al. 2007). Table 3 shows the physical –chemical analysis of surface water at the upstream and downstream region at Sungai Sembilang. All the results except for manganese (Mn) were below the standard limits allowed by the Environmental Quality (Control of Pollution from Solid Waste Transfer Station and Landfill) Regulations 2009. The concentration of Mn in the upstream region was already high due to the presence of other sources of Mn contamination in the upstream area. Additional sources of Mn from JSL increase the concentration at the downstream region.

Table 3. Physical-chemical analysis of surface water from Sungai Sembilang

Parameter Metal Concentration (ug/L) Standard limits Min Max Mean± SD pH 3.02 6.40 4.63±1.1 6.0 – 9.0 TDS 128 827 431±247 NA Conductivity 0.26 1.65 0.83±0.5 NA Temperature 26.35 30.52 27.85±1.3 40 Turbidity 2.36 34.0 11.62±8.9 NA Cr 0.00 36.16 5.73±11 50 Fe 55.83 1369.00 556.70±497 5000 Mn 43.84 674.50 327.16±190 200 268 Ahmad Razali Ishak et al. / Procedia - Social and Behavioral Sciences 222 ( 2016 ) 263 – 271

Pb 0.00 0.59 0.05±0.17 100 Zn 2.95 123.4 51.22±45 2000 Ni 1.16 23.32 10.67±6.8 200 Cd ND ND ND 10 Cu ND ND ND 200 As ND ND ND 50

The average heavy metal contents in surface water was arranged in the order; Fe >Mn >Zn > Ni >Cr > Pb respectively. Moderately high concentration of Fe (556.7 ug/L), Mn (327.1 ug/L), Zn (51.2 ug/L), Ni (10.7 ug/L), and Cr (5.73 ug/L) were detected in the water sample while Cd, Cu, and As were not detected in all the samples either in the upstream or downstream region. The lower concentration of heavy metal in the surface water might be due to of heavy metal in the water medium (Anita et al.,2010). The efficiency of leachate treatment plant of JSL was another reason of lower heavy metal concentration in Sungai Sembilang surface water. Comparison of physico-chemical analysis of surface water from Sungai Sembilang at the upstream and downstream region. According to statistical analysis by using independent T-test (pH, , Temperature, Conductivity, Turbidity, Mn, Zn, Ni) and Man Whitney (Fe, Cr, Pb), seven parameters are significantly different from the reading (p-value ˂ 0.05) between upstream and downstream region. pH value were highly acidic in the upstream (3.94) and became less acidic towards the downstream (5.31) after the landfill discharge point. High pH in the upstream might be contributed by other activities in the upstream region. The permissible limit of treated effluent from JSL for pH is 6.0 -9.0. The treated effluent may dilutes the surface water and increase the pH value in the downstream region. The turbidity value was relatively high at the downstream region indicate the influence of treated effluent discharge from the landfill. High turbidity and dissolved solid from raw leachate showed the possibilities of leachate effluent seeping out into Sungai Sembilang and affecting the turbidity and TDS in the surface water. Five heavy metal (Ni, Mn, Zn, Fe and Cr) also showed a significant different (P˂0.05) from the value between upstream and downstream region. The result indicates that the values were lower at the upstream and becomes higher in the downstream region. Even though the treated leachate discharged from the landfill were below the standard limit, continuous activity of release effluent will accumulate the heavy metal and increase the value in the downstream region.

3.3. Analysis of heavy metals in cockles

Blood cockles (Anadara granosa) are common sources of protein to the coastal communities of Southeast Asian countries such as Malaysia, Singapore, Thailand and Indonesia. Despite the good revenue earner and the sources of protein from the cockles, regular consumption of this has proven to be a health risk due to high exposure to . This condition worsened by the fact that molluscs possess the greatest metabolic capacity to accumulate contaminants in their tissues (Mirsadeghi et al., 2013). Table 4 shows the metal concentration in the cockles from Pantai Jeram cockle’s farm. The average heavy metal contents in cockles are in this order; Fe >Zn >Mn > Cu >Ni >Cr > Cr > Pb >Cd. High concentration of the essential element such as Fe and Zn found in cockles were 25.22 and 3.12 mg/kg respectively. High concentration of Fe in the cockles might be viewed as having some importance as good dietary supplements for anaemic patients (Noordin, 1994). Only Cd and Pb in cockles can be compared with Malaysian Food Regulation (1985) while, on the contrary, no limits are revealed for other metals in this study. The level of Cd and Pb were lower than the standard limit that is 0.04 and 0.07 mg/kg respectively. Other heavy metal such as Cu, Ni, Mn and Cr also present in the cockles sample, but the concentrations were lower, and the cockles can be considered safe for consumption.

Ahmad Razali Ishak et al. / Procedia - Social and Behavioral Sciences 222 ( 2016 ) 263 – 271 269

Table 4. Metal analysis of cockles from Pantai Jeram Cockles Farm

Parameter Metal Concentration (mg/kg) Food Regulation 1985 Min Max Mean± SD Cr 0.02 0.18 0.13±0.04 NA Fe 14.11 42.76 25.22±8.01 NA Mn 0.15 3.97 1.36±0.75 NA Pb 0.01 0.07 0.04±0.02 1.5 Zn 2.03 3.90 3.12±0.53 NA Ni 0.06 0.18 0.13±0.03 NA Cd 0.01 0.04 0.02±0.01 1 Cu 0.10 0.40 0.23±0.07 NA

Fig. 2. shows the seasonal variations of heavy metal in cockles collected from Jeram beach. By using independent T-Test, they are significantly different from concentration of Pb, Cu and Fe in the selected samples. High value of Fe (29 mg/kg) and Pb (0.047 mg/kg) detected during dry season while for Cu (0.27 mg/kg), the highest detection was during wet season. No significant different in seasonal variation had been identified in the rest of the heavy metals.

Fig. 2. Seasonal variation of heavy metal concentration in cockles from Pantai Jeram’s cockles farm

3.4. Health risk assessment

Oral reference doses (RfD) for calculation of THQ were based on USEPA (2000) which were 0.005, 0.046, 0.0004, 0.3, 0.02, 0.001, and 0.04 mg/kg for Cr, Mn, Pb, Zn, Ni, Cd, and Cu respectively. USEPA has not derived any toxicity values for Fe, so it is withdrawn from THQ calculation. The target hazard quotients (THQs) of studied metals through consumption of cockles for the residents (adults and children) in different races (Malay, Chinese and Indian) were derived in Table 5. The highest ADD of cockles’ consumption was Malay followed by Indian and Chinese due to higher cockle's ingestion rate (Peninsular: 4.92, Malay: 5.36, Chinese: 3.10, Indian: 3.61 g/day). Higher THQ value in children compared to adult is due to lower body weight assumption in the calculation. Overall, THQ value of cockles consumption was in this order; Pb >Mn > Cr >Cd >Zn > Ni > Cu.

270 Ahmad Razali Ishak et al. / Procedia - Social and Behavioral Sciences 222 ( 2016 ) 263 – 271

Table 5. Target hazard quotients (THQ) for individual metals caused by the consumption of cockles for population in Kuala Selangor

Population Non- Cancer risk hazard index (THQ) Pb Zn Ni Cd Cu Cr Mn Adult Peninsular 8.8E-02 9.1E-03 5.7E-03 1.7E-02 5.0E-03 2.2E-02 2.6E-02 Malaysia Malay 9.5E-02 9.9E-03 6.2E-03 1.9E-02 5.5E-03 2.4E-02 2.8E-02 Chinese 5.5E-02 5.7E-03 3.6E-03 1.1E-02 3.1E-03 1.4E-02 1.6E-02 Indian 6.4E-02 6.7E-03 4.1E-03 1.3E-02 3.7E-03 1.6E-02 1.9E-02

Children Peninsular 1.5E-01 1.6E-02 9.8E-03 3.0E-02 8.6E-03 3.9E-02 4.4E-02 Malaysia Malay 1.6E-01 1.7E-02 1.0E-02 3.2E-02 9.4E-03 4.2E-02 4.8E-02 Chinese 9.5E-02 9.8E-03 6.2E-03 1.9E-02 5.4E-03 2.4E-02 2.8E-02 Indian 1.1E-01 1.1E-02 7.2E-03 2.2E-02 6.3E-03 2.8E-02 3.3E-02

No THQ value was above than one which represents no potential health risk of cockle's consumption to the study population. Pb and Mn have the highest THQ value; 0.16 and 0.048 in Malay children, but this value is much lower than 1 and is unlikely to cause adverse health effect to the human. However, it is worth noting that this value is a highly conservative and relative index (Xilong et al., 2005). A THQ more or less than one may not show human experiencing the adverse health effects but this value can be an early alarm in estimating the potential health risk to the population. This finding agreed with Shafie et al, 2012 who conducted an environmental health impact evaluation on a sanitary landfill in Kuala Langat using a modelling software (CIRMA) based on environmental risk index and life cycle assessment approach. The study also arrived with a similar assessment that places sanitary landfill environmental condition in Malaysia within acceptable risk region.

4. Conclusion

Improper release of leachate effluent without proper treatment can contaminate the , surface water and also accumulated in marine organisms. In this study, high concentration of the were found in raw leachate of JSL and the efficient leachate treatment plant is required to reduce the pollutants from seeping into Sungai Sembilang. Significant different from a few heavy metal between the upstream and downstream region of JSL indicate the possibilities of several contaminants being discharged into the surface water. However, the little THQ value for all heavy metal in cockles represent no potential health risk to the study population. It is important to examine the metal concentration in raw leachate, surface water and cockles time by time for and to reveal the safety consumption of cockles to inhabitants.

Acknowledgment

The authors would like to thank the Institute of Research Management and Monitoring University Malaya (UM) for funding this research and to Worldwide Landfill Sdn. Bhd. for their cooperation in providing the landfill leachate. Ahmad Razali Ishak et al. / Procedia - Social and Behavioral Sciences 222 ( 2016 ) 263 – 271 271

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