Sarhad J. Agric. Vol.25, No.1, 2009

SOIL CONTAMINATION IN SWAT VALLEY CAUSED BY CADMIUM AND COPPER

MOHAMMAD NAFEES*, MOHAMMAD RASUL JAN**, HIZBULLAH KHAN*, NAJMA RASHID* and FOUZIA KHAN*

* Department of Environmental Sciences, University of Peshawar, Pakistan ** Institute of Chemical Sciences, University of Peshawar, Peshawar, Pakistan Corresponding Author’s Email: [email protected]

ABSTRACT The study was conducted in Swat Valley, North West Frontier Province, during 2006-07 with an attempt to investigate soil contamination caused by Cadmium (Cd) and Copper (Cu). In the study area, an increasing trend in uses of fungicides (copper sulfate + copper Oxychloride) and the use of compost as natural fertilizer and sewage water for irrigation were observed. Most of the people (residents and tourists) are using re-chargeable Cd-batteries. The trend of recycling is very week, and the Cd-batteries directly affect the agricultural fields through addition of compost. Among these, cadmium is a toxic heavy metal and copper, although, is a micronutrient, but its toxic level can create health hazards. For this propose 63 samples were collected from the entire Swat Valley and were analyzed for copper and cadmium, using Mehlich-3 method of extraction. A strong correlation was observed between Cd concentration and compost material, which was further confirmed by conducting interviews with farmer community. The soil samples collected from irrigated land, where natural fertilizer was used, were high in cadmium level while samples from the rainfed areas, where natural fertilizers use was less, were low in cadmium concentration. The same trend in irrigated and rainfed areas was also observed for copper, as majority of farmers use copper based fungicides, causing an increase in copper content of soil. Regulating the use of copper based fungicides and recycling of cadmium batteries can control the contamination and associated hazards.

Key Words: Soil contamination, Fungicides, Rechargeable Batteries, Mehlich-3

Citation: Nafees, M., H. Khan, M.R. Jan, N. Rashid and F. Khan. 2009. Soil contamination in Swat Valley caused by Cadmium and Copper. Sarhad J. Agric. 25(1): 37-43.

INTRODUCTION Copper is an essential micronutrient required for plants growth. It is associated with enzymes, and generally promotes the formation of vitamin-A in plants Martens and Westermann, 1991). The normal range of Cu in many plants is usually from 5-20 ppm. When the Cu concentration in plants is less than 4 ppm, then deficiencies are likely to occur. The characteristic symptoms of Cu deficiency in crop first appear in the leaf tips. The leaf tips become white and the leaves become narrow and twisted. Top leaves develop necrotic spots and brown areas, followed by withering and death of short tips. Copper deficiencies are usually corrected by the application of Cu fertilizers (Reed et al ., 1993). On the other side if copper concentration increase can also create problems. Such as LD 50 for rate is 30 ppm. In drinking water the safe level is defined as 2 ppm (EXTOXNET , 1994), where the upper limit for daily consumption is 10 ppm (England’s Water Quality Regulation Act 2000). Most of the copper salts are water soluble and can become part of ground and underground water and food cycle by adsorption, dissolution and complexation (Salam and Helmke, 1998).

Cadmium (Cd) is a non-essential trace metal naturally occurring in the biosphere (Alloway, 1995). Cadmium is chemically very similar to Zinc (Zn) (both occur in +2 oxidation state in water and soil) and is therefore substituted as an impurity in Zn-minerals and thereby cadmium is obtained as a by-product of the smelting of Zinc. Cadmium also occurs as a substitute for Ca in apatite and calcite, which can give rise to impurities in P-fertilizers. The use of Cd in batteries has dramatically increased since the 1980s, with comparative decrease in other cadmium containing products (Jansson, 2002). Soils that originate from alum shales are very likely to contain high concentrations of Cd. Besides these, other anthropogenic source includes P-fertilizer and atmospheric depositions into soils (Söderström and Eriksson (1996).

The average natural abundance of cadmium in the earth's crust has most often been reported from 0.1 to 0.5 ppm, which reached as high as 15 ppm in sedimentary rocks and marine deposits (Friberg et al. , 1992). Igneous and Mohammad Nafees et al. Soil contamination in Swat valley caused by cadmium and copper… 38 metamorphic rocks tend to show lower values, from 0.02 to 0.2 ppm (Cook and Morrow, 1995). The study area consists of igneous and metamorphic rocks (Irshad et al. , 2003) and 0.2 to 0.2 ppm is the expected range.

In Swat Valley the well-known manmade sources of Cu are inorganic fungicides in the form of copper Oxychloride and copper sulfate, while the sources of cadmium are phosphate fertilizer and rechargeable batteries cells. In this study an attempt has been made to investigate Cu and Cd level in selected soil samples collected from Swat Valley.

Study Area Swat Valley is situated in the north of Pakistan at 34° - 36° North Latitude and 71° - 73° East Longitude (GOP, 1985). It is a combination of three districts, namely Malakand (upper Malakand), Lower Dir and Swat district (Fig-1), enclosed by the sky-high mountains with an elevation ranging from 390-650 m above Mean Sea Level (MSL) and extends over a total area of 6288 Km 2 (Swat 5337 Km 2, Lower Dir: 475 Km 2 and Malakand 476 Km 2) (GOP, 2002). The soil is mainly sandy loam type occupying the maximum area with a land slope varying from 0 to 8 %, maximum slope of some hilly parts of the watershed is up to 22% and the soil depth ranges from 0 to 45 cm (Rashid et al. , 1999). The agriculture land is broadly divided into irrigated and rainfed. The rainfed land produce one crop per season and are not receiving fungicide (copper base) and mostly compost material are given to soil on regular basis. The irrigated land is further divided into two categories, one irrigated by canal diverted from River Swat and the other by natural stream, receiving sewage water. In this way the irrigated land receive heavy load of fertilizer, fungicides and natural manure (compost). Therefore, the soils of these areas were investigated for Copper (Cu) and Cadmium (Cd).

MATERIALS AND METHODS Soil Sampling Prior to sample collection, from Kalam to Kamala, the whole area was visited twice. After identifying major land types sampling points were decided. The criteria adopted for site selection was to cover maximum area that must be accessible and representative (Fig. 1). A stratified systematic composite soil samples vertically taken from 0 to 30 cm depth (after removing top lose materials such as gravel, leave and roots etc.) were collected from selected fields before sowing of crop (William, 1998). A particular field was divided into four equal blocks. Sample was taken from the middle of each block. For digging locally made equipment such as cutthroat auger and spade (shovel) made of stainless steel were used. Middle and Lower Swat was sampled in the month of November and December (winter) and upper Swat, because of accessibility problem was sampled in June-July. Soil samples collected from each agriculture field were mixed after collection in a plastic basket. To remove stones and roots the sample was sieved with the help of plastic sieve of 2 mm size and about 2 to 3 kg was packed in plastic bag. Generally soil in River Swat watershed is divided into three categories, each selected village one to three samples were collected separately (Fig. 1). Each sample, after collection was properly labeled, by putting number, name of the village, and longitude and latitudes. Samples were dried at room temperature and were stored in open mouthed plastic bottles (Vandre, 2001). These samples were then analyzed for Copper and Cadmium.

Fig. 1. Map showing study area and sample points analyzed for Copper and Sarhad J. Agric. Vol.25, No.1, 2009 39

The soil in the upper Swat is broadly divided into two classes, irrigated and rainfed. Eight samples were collected three from rainfed and 5 from irrigated. In middle Swat the area is divided the land is divided into irrigated (showlgari), semi irrigated (Jewardara) and rainfed ( Daman ) and three samples were collected from each locality. In this way total number of sample from each category of middle Swat are 12, 11 and 11 from rainfed, semi irrigated (Jewardara ) and irrigated ( Shoulgari ) area respectively. In lower Swat Malakand area can also be divided into the above three categories and total of 11 samples were collected ( rainfed 4, Jewardara 3 and Shoulgari 4). The Lower Swat, Chakdara side (Lower Dir) can be divided into two categories, rainfed and irrigated. In this way 10 samples were collected, 6 from rainfed and 4 from irrigated.

In total 27 different sites (villages) were selected for sampling. Sixty three samples (covering 10% of agricultural land) were collected for Copper and Cadmium analysis by following Mehlich-3 extraction method (Reed et al. 1993 and Walton & Alle, 2005).

Extraction with Mehlich-3

Mehlich-3 is a solution of five different chemicals with a particular ratio (0.2N CH 3COOH + 0.25N NH 4NO 3 + 0.015N NH 4F + 0.013N HNO 3 + 0.001M EDTA). 20 ml of Mehloch-3 solution was added to a sub- sample of 2 g from each soil sample and was agitated mechanically for five minutes at room temperature. The sample was filtered through Watman-42 filter paper. After filtration, the sample was analyzed on an Atomic Absorption spectrophotometers for Cd and Cu according to Mylavarapu and Kennelley (2002). The instrument was calibrated with 0.1, 1.0 and 10 ppm standard of Cd and Cu.

Interview The use of fungicides and presence of Cd - batteries were verified in the field by conducting interview among the farmers belonging to the villages from where soil samples were collected. A total 472 farmers were interviewed.

Samples Statistics For a representative sample an attempt was made to select the most accessible site and to cover almost all type of soil. Area wise 66.67 from District Swat, 17.46% from District Malakand, 15.87% from District Lower Dir. The area is broadly divided in to irrigated (60) and rainfed area (40%) and samples are collected in this proportion. The 3ed criterion was soil texture. For data analysis simple statistics were applied including percentage, calculation of maximum and minimum level, mean and standard deviation. For interview survey percentage was calculated and was presented on bar diagram.

RESULTS AND DISCUSSION Cadmium In the study area only one sample fall below 0.02 ppm (Kamala, Lower Swat, Chakdara area) and six samples below 0.2 ppm (Table I). In this way majority of samples are above from the natural level. This increase level can be attributed to different sources like, manufacture of electrical supplies, batteries, anticorrosive coatings for metals, bearing alloys and amalgam in dentistry (Tucker et al. , 2005).

The normal background level of Cd is 0.01 to 1 ppm. Regular consumption of plant containing 3 ppm Cd can poison man and animals (Tucker et al. , 2005). The minimum warning level in soil is 1.5 ppm (Jo and Koh, 2004). In the study area a range of 0.096 to 6.773 ppm of Cd was observed (Table I). In total of 26 samples (41.27%) the levels is 1.5 ppm or above in which 18 samples were from irrigated areas and eight were from rainfed areas. While only 14 samples (22.22%) fall below 1 ppm the natural level. Ten samples were from rainfed area and four samples were from irrigated areas (Table I & III). Hence the soil had got high level of Cd and need attention for its control.

In Swat Valley, the area irrigated from sewage or where natural fertilizers (compost) were used appeared high in Cd level. During enquiry it was observed that major source of Cd was battery cells used in Mobile, camera and toys. Proper awareness is required to encourage recycling and regulate the use of Cd batteries.

The major hazard exists in the form of plant up-take depending on crop type and soil conditions. Most field crops do not absorb appreciable quantities of Cd, but leafy vegetables such as spinach accumulate Cd. One of the earliest reports of Cd toxicity in people was traced due to the flooding of rice with water that drained from a mine Mohammad Nafees et al. Soil contamination in Swat valley caused by cadmium and copper… 40

(Welch et al.., 1991). Cadmium level is also affected by the application of phosphate and Zinc fertilizer. In phosphate fertilizer, cadmium level reached up to 163 ppm (Weiping et al. 2007) and the top largest source of soil cadmium. The safe level for P-fertilizer is 30-180 ppm (Singh, 1990) above this may encourage the availability of Cadmium to plants.

Table I. Concentration of Cadmium in soil samples collected from River Swat catchments and its comparison with Cd standards for soils by Soil environment conservation act, Korea 1999-2000 and SARA, 2005 Region Soil Type Total With Normal Range Mean Fall in Range Mean Above Range Mean No of Back Ground Warning Warning Samples Level of 0.01- Level of 1- level of 1ppm 1.5 ppm 1.6 ppm

No. of Sample No. of No. of Sample Sample Upper Rainfed 3 ------3 1.97 - 2.43 Swat 3.18 Irrigated 5 - - - 2 1.42 - 1.55. 1.49 3 1.42 - 3.34 4.79 Middle Rainfed 6 2 0.12 - 0.13 3 1.14 - 1.46 1.34 1 1.78 - 1.78 Swat 0.15 1.78 Matta Semi 6 1 0.30 0.3 3 1.27 - 1.43 1.34 2 1.82 - 1.97 Side Irrigated 1.97 Irrigated 6 1 0.31 0.31 5 1.39 - 1.50 1.45 - - -

Middle Rainfed 6 2 0.11 - 0.34 2 1.22 - 1.58 1.4 2 1.62 - 3.27 Swat 0.57 4.93 Mingora Semi 5 - - - 1 1.12 1.12 4 1.88 - 2.85 Side Irrigated 5.44 Irrigated 5 - - - 1 1.36 1.36 4 2.01 - 4.17 6.60 Lower Rainfed 4 3 0.11 - 0.24 - - - 1 2.38 2.38 Swat 0.44 Malakan Semi 3 - - - 1 1.32 1.32 2 4.13 - 4.29 d Side Irrigated 4.44 Irrigated 4 - - - 2 1.13 - 1.48 1.31 2 5.32 - 5.67 6.03 Lower Rainfed 6 3 0.10 - 0.36 2 1.35 - 1.36 1.35 1 3.16 3.16 Swat 0.73 Dir- Irrigated 4 2 0.15 - 0.35 1 1.47 1.47 1 1.75 1.75 Lower 0.55 Side

Copper (Cu) The minimum Copper concentration of 0.11ppm was observed in rainfed area of middle Swat, Mingora side and maximum concentration of 11.21 ppm was observed in the middle Swat, Matta side (Table II, Fig. 2). Generally the Copper concentration was high in irrigated area than in the rainfed area. In areas where copper base fungicides were in use, had high copper level. According to Jo and Koh (2004) soil with the average value of 50 ppm or above alarming value. In all 63 soil samples, Cu concentration in the study area appeared below the maximum allowable limits of 50 ppm. The mean value for rainfed area was in the range of 1.73 - 3.79 ppm while that of irrigated area ( Jewardara and shoulgari ) were in the range of 2.40- 6.70 ppm. Except the lower Swat, Chakdara area, all copper values in the irrigated areas were higher than their respective rainfed areas. In terms of micronutrient, copper concentration in study area was found in bio-available range. In thirty eight samples (60.32%) the copper was found 4 ppm or above (4.042 to 11.21 ppm) (Table-II), while twenty five samples (39.68%) ranged between 0.03 to 3.82 ppm. By comparing it with the standard, thirty number of samples fall below the normal range of 5-20 ppm. This is the amount enough for plant growth, but will not lead to toxicity. To keep the level of Cu within normal range, a check is required to regulate the use of Copper oxychloride and copper sulfate, which is used as fungicides in horticulture.

At present by comparing the Cu level with various limits, posed hazardous impacts on human being and other flora and fauna, but as the major source is copper oxychloride, which has negative impacts on soil biota, such as earthworm (Helling et al. , 2000 and Eijsackers et al. , 2005). .

Sarhad J. Agric. Vol.25, No.1, 2009 41

Table II. Status of Copper in soil sample collected from River Swat Catchments and its comparison with standard by Soil Testing Laboratory, South Dakota State University, General Nutrient Recommendations (http://plantsci.sdstate.edu/soiltest/Index.html ) Region Soil Type Total Samples Low in Cu 0.0 - Medium 0.11 to 0.2 ppm High in Cu 0.2ppm + No of 0.1ppm Sample No. of Rang Mean No. of Range Mean No. of Range Mea Sample e Sample Sampl n e Upper Swat Rainfed 3 ------3 1.43 – 5.87 3.79 Irrigated 5 ------5 5.18 - 10.02 6.70 Middle Rainfed 6 ------6 0.32 - 6.86 3.25 Swat Matta Side Semi Irrigated 6 ------6 0.72 - 6.92 5.52 Irrigated 6 ------6 0.76 - 11.21 6.32 Middle Rainfed 6 - - - 1 0.11 0.11 5 0.67 - 5.96 3.20 Swat Mingora Side Semi Irrigated 5 ------5 1.11 - 6.77 4.56 Irrigated 5 ------5 1.31 - 6.41 5.23 Lower Swat Rainfed 4 ------4 0.30 - 5.51 1.73 Malakand Side Semi Irrigated 3 ------3 1.60 - 8.27 4.85 Irrigated 4 ------4 4.02 - 9.85 6.56 Lower Swat Rainfed 6 ------6 0.34 - 6.13 3.20 Dir-Lower Side Semi Irrigated 4 ------4 0.37 - 5.46 2.40

Table III . Copper (Cu) and Cadmium (Cd) concentration in ppm of Selected Soil Samples collected from River swat Watershed Region S Number Heavy Min Max Mean Std Dev Type of Metals Samples Upper Swat, Kalam to RF 3 Cd 1.78 3.18 3.41 0.63 Fathehpure Cu 1.43 5.87 3.79 2.39 (Total No. of Sample 8) IR 5 Cd 1.42 4.79 2.6 1.39 Cu 5.18 10.02 6.7 1.9 Middle Swat Northern Matta RF 6 Cd 0.12 1.78 1.01 0.71 Side Cu 0.32 6.86 3.25 3.03 (Total No. of Samples= 18) IR J 6 Cd 0.3 1.97 1.35 0.59 Cu 0.72 11.21 5.52 4.07 IR S 6 Cd 0.31 1.5 1.26 0.47 Cu 0.76 10.95 6.32 4.41 Middle Swat Southern RF 6 Cd 0.11 4.93 1.67 1.7 MIngora Side Cu 0.67 5.96 3.2 2.17 (Total No. of Sample = 16) IR J 5 Cd 1.12 5.44 2.51 1.68 Cu 1.11 6.7 7 4.56 2.71 IR S 5 Cd 1.36 6.6 3.61 2.21 Cu 1.31 6.53 5.23 2.23 Lower Swat Malakand Area RF 4 Cd 0.11 2.38 0.77 1.08 (Total No. of Sample 11) Cu 0.3 5.51 1.73 2.52 IR 3 Cd 1.32 4.44 3.3 1.72 Cu 1.6 8.27 4.85 3.34 IR 4 Cd 1.13 6.03 3.49 2.54 Cu 4.04 9.85 6.56 2.89 Lower Swat Southern, RF 6 Cd 0.1 3.16 1.16 1.12 Lower Dir, Chadara Sid Cu 0.34 6.13 3.2 2.36 (Total No. of Sample = 10) IR 4 Cd 0.15 1.47 0.72 0.67 Cu 0.37 5.46 2.4 2.69 RF= Rainfed, IR J= Irrigated Jewardara, IR S = Irrigated Showlgari Mohammad Nafees et al. Soil contamination in Swat valley caused by cadmium and copper… 42

Interview The interview survey shows that out of the total respondents 76.45% farmers were found using Cd batteries in one form or another and used to discard them directly in the solid waste, used as a manure for agriculture fields. The major uses of Cd are in the form of Cd-batteries, which are widely used in toys, torches, mobile phone, etc. Besides, Cd is also used in certain fungicides and herbicides formulations. The interview results show that 65.56% respondents (Fig-II) were found ignorant to differentiate between rechargeable and non-rechargeable batteries and their associated hazards. 45.55% people found Cd batteries in the compost material. 30% of the respondents blamed tourists and 40% blamed children and young people for throwing batteries after use. Besides, in lower and middle Swat Area, municipal wastewater is discharged in streams, used for irrigation in the semi-irrigated area and is therefore a clear evidence of anthropogenic Cd sources. Copper oxychloride was found the most famous fungicides. 69.54% farmers preferred copper oxychloride 13.35% copper sulfate and 18% other pesticides. The use of micro-fertilizer was not observed.

120

100 100

80 76.483 69.492 65.466

60 45.551

40

18.432 20 13.347

0 1 No of Respondents 100 Use of Copper Oxychloriode 69.492 Use Copper Sulfate 13.347 Use of Other fungicides 18.432 Rechargible bateries 76.483 Having no knowledge of Cd Associated 65.466 hazerd Batery cell observed during distribution of 45.551 Compost Fig. 2. Diagram showing anthropogenic sources of Copper and Cadmium

CONCLUSION All the analysis and interview survey showed that significant quantities of Cd and Cu are present in the soil. Copper concentration was found within the permissible limit of 5-20 ppm. Copper exists in a normal level in all areas but in the middle and lower Swat its concentration in irrigated area was higher. In irrigated areas (both Jewardara and Shoulgari ) the ranges of Cu level were 5.18 to 10.02 in upper Swat, Matta side 0.72 to 10.95 ppm, in upper Swat, Mingora side 1.12-6.53, in Lower Swat, Malakand side 1.65 – 9.85 ppm and Lower Swat, Lower Dir Side 0.37-5.46 ppm, which is high from their respective rainfed areas. This is directly attributed to the use of copper based fungicide. Cadmium level was above the permissible limits in 26 samples. The concentration was observed higher in the irrigated areas ( Jewardfara and Shoulgari ) than that of the rainfed. In upper Swat the Cd level ranges for irrigated area ( Jewardfara and Shoulgari ) were 1.42-4.79 ppm, middle Swat, Matta side 0.3-1.5, middle Swat Mingora side 1.12-6.60 ppm and lower Swat Malakand side 1.32-6.03 ppm and were high than their respective rainfed area. The interview survey shows that Cd level is mostly correlated with the anthropogenic sources, especially Cd-batteries. Therefore, a detail survey is recommended along with initiation of recycling Cd products, especially rechargeable batteries.

ACKNOWLEDGMENT The authors are grateful to Prof. Dr. Tahir Shah, NCE in Geology, University of Peshawar and Mr. Umar of Centralized Resource Laboratory, University of Peshawar for helping us in heavy metal analysis. Special thanks to Dr. Johar Ali, Sociology Department University of Peshawar for his technical help in designing of interview schedule. Thanks to all farmers who spared their valuable time and helped us in samples collection and gave us valuable information and enabled us to write this article.

Sarhad J. Agric. Vol.25, No.1, 2009 43

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