Quantitative assessment of heavy metals ...

Academic Social research

RNI No. 1276610 ISSN No. 2456-2645

Quantitative assessment of heavy metals concentration and their correlated risk study in soil of urban area of Unnao & Kanpur, UP, India Saumya Singh R.K.Kaushal Pollution in soil with heavy metals has become common across the globe due to increase in geologic and anthrapogenic activities. The present study related to soil pollution has been carried out in area of Unnao and Kanpur ,which are cities of Uttar Pradesh, India .Objective of this study to quantify the heavy metal concentration in selected sites of Unnao and Kanpur and their Hazard Quotient and Cancer risk and their statistical correlation analysis for workers and people resite and work on these sites. Selected six sites for study are- Battery shop in Unnao, common waste dumping site between Kanpur and Unnao road, Heavy vehicle zone , Rawatpur Kanpur, Muncipalwate dumping site, Unnao, Panki Power Plant Kanpur and Automobile repairing shop Unnao. Collection of soil samples from various sites from three places, near the site , 500 meter away from the collection site and 1 km away from the selected sites. Collected samples were processed for standard procedure for analysis of Lead, Cadmium, Chromium Nickel, Copper and Zinc concentration in soil .Result of analysed data showed variation in heavy metals concentration in almost all cases. Heavy metal concentration for Lead, Cadmium, Chromium and Nickel crosses the safe limits of heavy metal concentration in soil for Indian Standard (Awashthi 2000), WHO/FAO (2007) and European Union Standard (EU 2002).Mathematically analysed data showed results that Lead concentration has adverse health effect( HQ>1). In case of cancer risk maximum risk is found in case of lead maximum 345 chances of cancer in one million people are observed in case of lead, there is no cancer risk is observed in case of cadmium. And in case of Nickel and chromium little cancer risk is observed. Cancer risk and hazard quotient are positively correlated in case of Lead, Cadmium, Chromium and Nickel (r =1) shows positively correlation betwe en randomly selected data . 1. INTRODUCTION The term heavy metal refers to any metallic chemical elements that has a relatively high density and toxic or poisonous at low concentration Heavy metals can enter a water supply by industrial and consumer waste , or even from acidic rain breaking down soils and releasing heavy metals into streams, lakes, rivers, and groundwater. Urban soils are an important indicator of urban environmental quality as they act as a sinks andsources for metals and other pollutants (Kelly et al., 1996; Mielke et al., 1999). Soils polluted with metals can threaten human health, soil microbial community, water resources (surface and ground), food quality, flora and fauna. The possible sources of soil metal pollution include atmospheric deposition of dust and aerosol (Simonson, 18 | O c t o b e r t o D e c e m b e r 2 0 1 5


RNI No. 1276610 ISSN No. 2456-2645

1995), vehicle emissions (Yassoglou et al., 1987; Surthland et al., 2000) and various industrial activities (Schuhmacher et al., 1997; Krishna and Govil, 2005; Li et al., 2007 and others (Thornton, 1991). In recent years, soils have been evaluated as a diagnostic tool of environmental conditions that influence health (Abrahams, 2002; Davydova, 2005). Numerous studies have been reported on metals contaminations in urban soils around the world (De Kimple and Morel, 2000; Li et al., 2001; Chen et al., 2005; Lee et al., 2006; Yay et al., 2008) and in India (Govil et al., 2001; Krishna and Govil, 2004, 2005, 2008, Rawat et al., 2009).Heavy metals can enter a water supply by industrial and consumer waste, or even from acidic rain breaking down soils and releasing heavy metals into streams, lakes, rivers, and groundwater. Inhalation and ingestion are the two routes of exposure, and the effects from both are the same. Unnao and Kanpur is a prominent industrial hub and one of the fastest growing cities in the state of Uttar Pradesh, India. The city houses various types of highly polluting industries including textiles, lead- reprocessing units, electroplating or galvanizing and others (including pharmaceuticals, chemicals, tanneries, ceramics, pesticide formulations, etc). Currently, in India, there is no regulatory criterion of metals concentrations in soils. Therefore, present study was conducted to: (1) determine the concentration of (Cu, Cr, Pd, Cd, Zn and Ni) in soil collected from Unnao and Kanpur (2) Comparison between observed value and Indian and European standard and (3) to estimate carcinogenic and non-carcinogenic health risk (4) person correlation coefficient for hazard quotient and cancer risk. Materials and M ethodology 2.1 Study site-Unnao and Kanpur are districts of Uttar Pradesh situated 27æ%40 North and longitude 80æ%00 East, 26æ%28’North and longitude 80æ%24’East respectively. Unnao has total area of 5000 km 2 and Kanpur has 605km2. Total population of the city Unnao and Kanpur 177,658 and 5.03 million respectively .Therapid population growth is mostly because of its industrial development. Major land uses in the city are primarily industrial, residential and commercial. Agriculture holds a little share in the main city and is dominated in the peri-urban area of the district. The climate of this region is tropical to temperate with extreme temperature condition in summer (upto 43æ%C) and winter (upto 3 æ%C). 2.2 Sampling and analysis-In the present study, the scope of sampling area focused on the urban area .A total 18 samples were collected (top soil, 0-20 cm) from 6 major sites sampling sites along with their category and sample name are arranged in the table19 | O c t o b e r t o D e c e m b e r 2 0 1 5


Sl. No. Site Category 01 Battery shop 02 Battery shop 03 Battery shop 04 Automoblie shop 05 Automobile shop 06 Automobile shop 07 Common waste 08 Common waste 09 Common waste 10 Heavy vehicle zone 11 Heavy vehicle zone 12 Heavy vehicle zone 13 Muncipal waste site 14 Muncipal waste site 15 Muncipal waste site 16 Panki power plant 17 Panki power plant 18 Panki power plant

RNI No. 1276610 ISSN No. 2456-2645

Sample name Near the shop BS1 500 mt away from shop BS2 1km away from shop BS3 Near the shop AS1 500mt away from the shop AS2 1km away from shop AS3 Near the site CW1 500mt away from the site CW2 1km away from the site CW3 Near the zone HV1 500 mt away from HV2 1km away from the zone HV3 Near the site MW1 500 mt away the site MW2 1km away from the site MW3 Near the power plant PP1 500mt away from the plant PP2 1km away from the plant PP3

Each of the soil samples consisted of about 3sub samples collected with a stainless steel hand auger. The randomly collected sample from the surroundings of each sites were mixed thoroughly to obtain bulk sample. All soil materials that were touched by the metallic digging tools were carefully eliminated from the samples before packing to avoid cross –contamination. The collected samples were stored in the polythene bags for transport and storage soil was air-dried and sieved through a 02 mm mesh, and then stored in sealed polythene bags until analysis. The total concentrations of metals in the soils were determined according to EPA standard method 3050B (USEPA,1996). This strong acid digestion method dissolve almost all thee lements that could become environmentally available (Crnkovic´ et al.,2006). In brief 1g of sample was accurately weighed into 250ml flask for digestion on hot plate with 10ml of 1:1HNO3 without boiling (at 95 æ%C).It was then refluxed with repeated additions of conc.HNO 3 until no brown fumes were given off by the sample. After cooling, 2ml of deionized water and 3ml of 30 percentH 2O2 (maximum 10ml) was added slowly without allowing any losses. The mixture was refluxed with 10ml of conc. HCl at 95 1C for 15 min. After cooling, digestate was filtered, transferred in to a 100 ml volumetric flask, and diluted to the mark with deionized water. Solutions were stored in high density polyethylene vials 20 | O c t o b e r t o D e c e m b e r 2 0 1 5


RNI No. 1276610 ISSN No. 2456-2645

at 4 æ%C until instrumental analysis. Metal concentrations in the digestion solution were measured using flameatomic absorptions pectrometry. 1.3 Risk assessment -Risk assessment is gathering of data that are used to relate response to dose. Such dose response data can be obtained with estimates of likely human exposure to produce overall assessment of risk. Risk management, on the other hand, is the process of deciding what to do. 2.31Non cancer risk assessment in human via ingestionNon-cancer risk assessment in the present study based upon the consideration to human exposure to soil via ingestion( oral intake).Non cancer risk have been analysed by calculating Hazard quotient (HQ),is the ratio of average daily dose(ADD) to the reference dose (Rfd). A HQ < 1 suggests unlikely adverse health effects, whereas HQ > 1 suggests the probability of adverse health effects. Assumptions for daily intake calculations are as follows: (a) Average body weight (adult) = 60 kg; (b) Amount of air breathed daily (adult) = 20 m 3; (c) A worker works for 15 years at a recycling site; (d) Soil/dust ingestion rate (child) = 200 mg/day; (e) Average time = 365 days; (f) Average life (years) = 65 years. For people working at a recycling site it is assumed that they work 8 h/day, 5 days/week. Oral reference dose for heavy metals and absorption factor according to (Danish Environmental Protection Agency, 2003; FAO and WHO, 1972; USEPA, 1993, 1999 ). In tableMetal Reference dose Absorption factor Lead (Pd) 3.5E-03 6.0 E-01 Cadmium (Cd) 1.0E-03 5.0E-02 Copper (Cu) 4.0E-02 5.0E-01 Zinc (Zn) 3.0E-01 2.0E-01 Nickel (Ni) 2.0E-02 1.8E-02 Chromium (Cr) 3.0E-03 1.0 E-01 2.32 Cancer Risk- The chronic cancer risk has been calculated for Pb, Cd, and Cr(VI) and Ni due to air inhalation and soil/dust ingestion for their reported concentrations . Total dose = (Contaminant conc.) × (Intake rate) × (Exposure duration) × (Absorption factor) Risk = CDI (mg/kg/day) × Potency factor (mg/kg/day)where CDI is chronic daily intake. Potency factor for Pd, Cd, Cr and Ni are 4.20E-02, 1.50E+ 01,5.10E+02 and 9.10E-01 respectively. USEPA IRIS data base (1989).

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RNI No. 1276610 ISSN No. 2456-2645

3. RESULTS AND DISCUSSION 3.1 Heavy metal concentration-Heavy metal concentration was calculated for all 18 samples in which Lead and Nickel concentration found maximum for automobile repairing shop for sample AS1 and AS3 respectively. And chromium and Zinc found maximum for Panki Power Plant, Kanpur for sample PP1 and PP2 respectively .And Copper is maximum found on Common waste dumping site for sample CW1 .and Cadmium is found maximum on Heavy vehicle zone for sample HVI. 3.2 Comparison between observed values of heavy metal concentration and safe limits of Indian and European Standards for soilComparison chart results are summarized in a table in which result are in form of ,0 and 1 where 0 represent the lower value than the standard values of heavy metals observed form the particular site and 1 represent the higher values of observed concentration than the standard values of heavy metals . Symbol IND represent the term Indian Standard and EU represent the term European Standard. And sample name represent its site and numbers alongwith sample name represent its category of site means it shows near the site or 500 mt away from the site or 1 km away from the site. S. Sample Heavy metals Pd Cd Cu Zn Ni Cr IND EU IND EU IND EU IND EU IND EU IND EU 01 BS1 1 1 0 0 0 0 0 0 0 0 1 1 02 BS2 1 1 0 0 0 0 0 0 0 0 1 1 03 BS3 1 1 0 0 0 0 0 0 0 0 1 1 04 AS1 1 1 0 0 0 0 0 0 1 1 1 1 05 AS2 1 1 0 0 0 0 0 0 1 1 1 1 06 AS3 0 0 0 0 0 0 0 0 1 1 1 1 07 CW1 0 0 0 0 0 0 0 0 0 0 1 1 08 CW2 0 0 0 0 0 0 0 0 0 0 1 1 09 CW3 0 0 0 0 0 0 0 0 0 0 1 1 10 HV1 1 1 0 0 0 0 0 0 0 0 1 1 11 HV2 0 0 0 0 0 0 0 0 0 0 1 0 12 HV3 0 0 0 0 0 0 0 0 0 0 1 0 13 MW1 0 1 0 0 0 0 0 0 1 1 0 0 14 MW2 0 0 0 0 0 0 0 0 0 1 0 0 15 MW3 0 0 0 0 0 0 0 0 0 1 0 0 16 PP1 0 0 0 0 0 0 0 0 0 0 1 1 17 PP2 0 0 0 0 0 0 0 0 0 0 1 1 18 PP3 0 0 0 0 0 0 0 0 0 0 1 1 In the result we found that chromium (Cr) concentration in soil is higher than the safe limits concentration for soil of Indian Standard values and 22 | O c t o b e r t o D e c e m b e r 2 0 1 5


RNI No. 1276610 ISSN No. 2456-2645

European Standard values for all sites and category except municipal solid waste dumping site. Lead (Pd) is metal which crossed the safe limit of Indian and European standard for all category of automobile repairing shop and battery shop .And for category 1(near heavy vehicle zone) for heavy vehicle zone crossed the safe limits of Indian and European standard values. Ni crossed the same limits of Indian and European standard for automobile repairing shop in all categories. And crossed only European Standard values for municipal waste dumping site in all categories 3.3 Hazard Quotient-Hazard quotient is mathematically calculated for all 18 samples collected from area of Unnao and Kanpur for six heavy metals Pd, Cd, Cu, Zn, Ni and Cr. In case of Pd for Automobile repairing shop sample (AS1) we found adverse health effect (HQ>1). At concentration 24150 mg/kg HQ is calculated 1.081533121 which is greater than one so it showed adverse health effect on health, and for rest 17 samples hazard quotient is less than one so its showed unlikely adverse health effect on health. 3.4 Cancer Risk- Cancer risk is calculated for all 18 soil samples for heavy metal Pd, Cd, Ni and Cr maximum risk is found in case of lead maximum 321 chances of cancer in one million people are observed in case of lead for sample AS1 at concentration 24150 mg/kg observed risk is 1.603213909. ,there is no cancer risk is observed in case of cadmium. And in case of Nickel maximum 34 chances of cancer in one million people and for chromium maximum 7 chances of cancer risk was observed. 3.5 Correlation between hazard coefficient and cancer risk– Pearson correlation coefficient known as r, R or Pearson’s r , a measure of the strength and direction of the linear relationship between two variables that is defined as( sample) covariance of variables divided by the product of their (sample) standard deviations. The correlation coefficient of two variables, sometimes simply called their correlation. If the correlation coefficient is close to 1, it would indicate that the variables are positively linearly related and the scatter plot falls almost along a straight line with positive slope. For -1, it indicates that the variables are negatively linearly related and the scatter plot almost falls along a straight line with negative slope. And for zero, it would indicates a weak linear relationship between the variables..



Metal

Value of r for HQ

lead Cadmium Nickel Chromium

r=1 r = 0.964544 r = 0.569566 r=1

RNI No. 1276610 ISSN No. 2456-2645

Value of r for HQ r =0.929194 r= 0.98179 r = 0.857207 r = 0.904259


Result and concentration& Risk Positively correlated Positively correlated Positively correlated Positively correlated


RNI No. 1276610 ISSN No. 2456-2645

4. Conclusions- Study was carried out in the assessment of Heavy Metal concentration and their Risk in the urban area of soil of Unnao and Kanpur. In the study it was found that there is high % of heavy metals accumulation in soil in comparison to standard values in this area .On the basis of study several conclusion were concluded–1.) Lead and Nickel concentration found maximum for automobile repairing shop. And chromium and Zinc found maximum for Panki Power Plant. And Copper is maximum found on Common waste dumping site and Cadmium is found maximum on Heavy vehicle zone. 2.) Chromium (Cr) concentration in soil is higher. Than the safe limits concentration for soil of Indian Standard values and European Standard values for all sites and category except municipal solid waste dumping site. 3.) Lead (Pd) is metal which crossed the safe limit of Indian and European standard for all category of automobile repairing shop and battery shop .And for category 1(near heavy vehicle zone) for heavy vehicle zone crossed the safe limits of Indian and European standard values. 4.) Ni crossed the same limits of Indianand European standard for automobile repairing shop in all categories. And crossed only European Standard values for municipal waste dumping site in all categories. 5.) Adverse health effect only found for Lead (Pd) at concentration 24150mg/kg from automobile repairing shop. 6.) Maximum cancer risk found for Lead and least for Cadmium.7.) For all metals their concentration and hazard quotient are positively correlated.8-) For all metals hazard quotient and cancer risk is also found positively correlated. References 1. USEPA (US Environmental Protection Agency) (1993) Reference dose: Description and use in health risk assessments, Background Document 1A. Available at: http://www.epa.gov/iris/rfd.htm (accessed 22 March 2012). 2. USEPA (US Environmental Protection Agency) (1999) Short Sheet. IEUBK model bioavailability variable. 23 June 2012). 3. USEPA (US Environmental Protection Agency) (1998) Integrated Risk Information System (IRIS). Available at: http://www.epa.gov/iris/ (accessed 23 June 2012). 4. USEPA (US Environmental Protection Agency) (2007) Management of electronic waste in the United States: Approach two. Available at: http://www.epa.gov/ecycling/manage.htm (accessed 2 April 2013). 5. FAO (Food and Agriculture Organization of the Nations) and WHO (World Health Organization) (1972) Evaluation of Certain Food Additives and Contaminants. Mercury, Lead and Cadmium.16th report of the joint FAO/WHO Expert Committee on Food Additives. Geneva: World Health Organization. 6. USEPA. 2000. Risk-based Concentration Table. United State Environmental Protection Agency, Washington, DC. 7. WHO/FAO. 2007. Joint FAO/WHO Food Standard Programme Codex Alimentarius Commission 13th Session. 25 | O c t o b e r t o D e c e m b e r 2 0 1 5


RNI No. 1276610 ISSN No. 2456-2645

8. USEPA (US Environmental Protection Agency)., 1989. Risk Assessment Guidance for Superfund. Human Health Evaluation Manual. EPA/540/189/002, vol.I. Office of Solid Waste and Emergency Response. US Environmental Protection Agency. Washington, DC, 9. US EPA, 1991b.Role of the Baseline Risk Assessment in Superfund Remedy Selection Decisions. Office of Solid Waste and Emergency Response. OSWER Directive 9355, 0–30. 10.USEPA (United States Environmental Protection Agency), Method 3050B:,1996. Acid Digestion of Sediments, Sludges and Soils, (revision 2).
