- To determine extent of contamination of water, soil and plants w.r.t. Cd, Cu, Fe, Pb, Ni and Co in different zones of Faisalabad city.
- To determine the air pollutants like CO2, CO, NOx, SO2, Cl, smoke and aerosol contents in different zones of Faisalabad city area.
- To estimate aerosol contaminants like Cd, Cu, Fe, Pb, Ni and Co in different zones of Faisalabad city area. .
- To develop a GIS data base and digital maps of water, soil and air pollution of different zones of Faisalabad metropollitin area.
Faisalabad has made rapid strides in the field of industry after independence. Now, there are dozens of textile mills with other subsidiary units. Approximately, there are 512 large industrial units, of which 328 are Textile units, 92 engineering units and 92 chemicals and food processing units. There are also some 12000 house-hold industries, which include some 60000 power loom factories. All these industrial units are releasing a large volume of untreated city/industrial waste water into unlined drains from where farmers are utilizing this effluent for raising crops (Arif, 1994; Krishna and Govil, 2005).
Some survey studies conducted by our group (Soil and Water Chemistry) have shown that most of the industries (Ghee, Dying, Textile, Printing, Tanning and Chemicals) in Faisalabad are discharging effluents into open drains and irrigation channels without any treatment. From the previous research, it was found that raw city effluent at different sites within the municipal limits of Faisalabad during 1998 and 2007 had high EC, SAR and RSC to render them unfit for irrigation. The concentration of Cd, Mn, Pb, Ni, Cu and Fe were recorded above while that of Co was below permissible limit for irrigation considering recommendations (Ayers and Westcott, 1988). In vegetables commonly grown in urban and sub-urban lands (Radish, Sugar beet, Garlic, Spinach), metal concentrations were higher in leaves than in the respective edible parts. This situation warrants appropriate risk assessment and management measures to be taken where raw effluent is being used for irrigation of crops.
Geographic information system (GIS) is a computer-based information system that enables capture, modeling, manipulation, retrieval, analysis and presentation of geographically referenced data. On regional and national scales, the geochemical mapping of trace and major elements can be used as a tool for visualization, to make it easier to identify the possible locations of contaminated areas. Furthermore, this allows the analytical data to be manipulated with this additional information, offering several advantages in trace metal assessments of urban soils, effluents, plants and air. A better understanding of interactions between trace metals and the urban environment can also be obtained by overlaying the trace metal distribution with key urban features, like topography, traffic networks and locations of buildings and industrial facilities (Li et al., 2004; Lee et al., 2005).
Increase in population at alarming rate has created manifold problems for the inhabitants of big population centers like Faisalabad. Deterioration and contamination of air quality is one of the treat to human being in the present era of industrialization and urbanization. The quality of air is directly linked with the type and number of industries, number and types of vehicles plying on roads in an area. Despite its third place in country on population basis, there is no scientific literature available for air quality status and extent of Faisalabad city.
Summary and Conclusions
Pollution of heavy metal is a great threat to the environment particularly in periurban areas where raw sewage water is used for irrigation of crops. Heavy metals are highly toxic substances entering from anthropogenic sources (mining, industrial effluent, pesticides and fertilizers and vehicle exhaust) to the environment and polluting soils, waters and atmosphere. Soil, plant and irrigation water samples were collected at 4 km x 4 km grids to determine the contamination of heavy metals in the Madina, Lyallpur, Jinnah and Iqbal towns of the Faisalabad Metropolitan during 2010. Soil samples at 0-15 and 15-30 cm depths were collected and analyzed on atomic absorption spectrophotometer for AB-DTPA extractable metals (Cd, Pb, Ni). Plant shoot samples were taken from the same site from where soil was taken and digested in diacid mixture (HClO4:HNO3 in the ratio of 1:3) and analyzed for metals on atomic absorption spectrophotometer. Irrigation water samples were taken from the same place from where soil and plant sample were taken. The main objective of this study to determine the metal contamination in soils, plants and waters, aerosols contents, smoke opacity and air composition and preparation of GIS maps of the pollution hit areas in the four towns of Faisalabad Metropolitan. Analysis of soils, irrigation waters and plants collected from the Madina and Lyallpur Towns is presented in this report while that for samples from Jinnah and Iqbal Towns is in progress.
- Chemically soils of both the towns were mostly normal and moderately calcareous in Madina and Lyallpur Towns w.r.t. to pHs, ECe and SAR. Values of these parameters were higher in Madina than that of Lyallpur Town soils Similarly values were higher at 00-15 cm than that at 15-30 cm depth for all the samples.
- Concentration of available Cd, Pb and Ni metals in soils is still below the phytotoxic levels for most of plants that may be hazardous for humans and animals, values being higher at 00-15 cm than that at 15-30 cm depth. This seems due to rapid transformation of metals from available to non-available forms which also restricted their movement below the surface layers of soils.
- In most of the plants samples, Cd, Pb and Ni concentration was within permissible levels for phytotoxicity but unsafe for livestock and humans consumption.
- Almost all the ground water samples were unfit for irrigation owing to high EC, SAR and/RSC. Concentration of metals was low and within prescribed limits for irrigation quality. However, continuous use is creating soil salination, sodication and inducing build up of metals in surface soil layers.
- All he sewage water samples were unfit for irrigation w.r.t. EC, SAR and RSC, but marginal w.r.t. metals.
- Canal water at farm was of much inferior quality compared to that of main canals owing to unauthorized disposal of domestic and small industry waste waters into water courses.