Source apportionment and spatial–temporal variations in the metal content of surface dust collected from an industrial area adjoining Delhi, India
Highlights
► Faridabad industrial area adjoining Delhi have high surface dust pollution load for Cd, V, Co, Ba, Ti, Ni, Cu, Cr and Zn. ► Sampling sites are least to highly polluted but specific to metal(s) and sampling season. ► Major metal pollution sources are mixed type industries, crustal, vehicular emissions, oil and battery burnings. ► Compared to large, small and medium scale unorganized industries add more pollution. ► Nature of industries, changes in land use pattern and shifting of small scale industries cause spatio-temporal variations.
Introduction
Emissions from industries, thermal power plants, fossil fuel burning from vehicles and construction activities are major anthropogenic contributors of metals and metalloids in the urban environments (Khlifi and Hamza-Chaffai, 2010). Although soil–crop system is taken as the main path through which humans are affected by the metals present in the environment (Liu et al., 2007, Sharma et al., 2007, Bose et al., 2008, Pandey et al., 2009), urban dust, especially in industrial areas and road sides not used for growing food crops, influences public health to a significant extent (De Miguel et al., 1997, Mielke et al., 1999, Madrid et al., 2002). Dust inhalation and ingestion, and hand mouth interactions are key pathways through which all human beings, particularly children, are exposed to metals and metalloids (Watt et al., 1993, Meyer et al., 1999, Rasmussen et al., 2001). This leads to high metal levels in blood, and affects intelligence and behavior of the affected person as has also been reported by Dietrich et al. (1990) for lead toxicity. The chronic adverse effects of the metals are well established (Khlifi and Hamza-Chaffai, 2010 and more references therein). This phenomenon is more evident in those urban areas, where multiple sources release large amounts of metals into the environment including atmosphere and soil (Nriagu, 1998, Bilos et al., 2001, Li et al., 2001). Liu et al. (2009) have reported high cancer risk (> 1 × 10− 6) for Cd, Ni, and Cr in workers occupationally exposed to industrial emissions. Therefore, the need for the better understanding of urban dust pollution has been recognized by several researchers (De Kimple and Morel, 2000, Manta et al., 2002) and research has been carried out worldwide (Kelly et al., 1996, Chen et al., 1997, Mielke and Reagan, 1998). The other important aspect of urban dust pollution is that it is not limited in time and space i.e. there is long term influence extended to space with contamination of air, water and soil (Fujiwara et al., 2011 and references therein).
In developing countries like India, there are enormous problems associated with the metal pollution of surface dust due to industrial activities. Faridabad city located adjacent to the national capital city of India, New Delhi, houses many industries like electroplating, metal coating, tire, tractor, power plant, etc. ranging from small to large scale. It is known that metal plating, copper motor burning and rewiring, batteries, metal alloy industries contribute both ferrous and nonferrous metal pollution in the environment, especially in urban dusts (Khlifi and Hamza-Chaffai, 2010). These authors have reviewed the adverse human health effects of ferrous as well as nonferrous metals such as Pb, Ni, Cr, Cd and Zn. The metal pollution in this region has not been looked into, rather there is lack of information on metal pollution in such areas having multiple types and different scales (small to large) of industries. The urban surface dust samples were collected from nearly 20 locations during three seasons i.e. pre-monsoon, post monsoon and winter from Faridabad industrial area and analyzed for different metals. The metal data is interpreted to understand the metal distribution, spatial and temporal variations, and their sources in the surface urban dust samples, and to assess related environmental and health effects in this region.
Section snippets
Study area
Study area for the present work includes Faridabad, an industrial township of Haryana state (known as the “Manchester of India”) located around 25 km from the central part of the National Capital city of India, New Delhi (see Supplementary material: Fig. AF 1). The geographical location of Faridabad town is 28° 25′ 16″ North Latitude and 77° 18′ 28″ East Longitude covering nearly 2151.00 km2 (http://faridabad.nic.in/socio-ec.htm). This township shares the common boundary on its north with Delhi,
Sampling and analysis
Three sampling campaigns during winter, pre-monsoon and post monsoon seasons were performed for the collection of surface dust from the pre-determined sampling points in the study area to assess the nature and level of pollution caused by mixed type of industries. The whole area was divided in 500 m × 500 m size grid to get representative samples from all parts of the Faridabad industrial area. Out of the total collected samples, we selected only 21 samples as representative of different industrial
Results and discussion
The chemical data generated for selected metals Fe, Al, Mn, Ti, Cu, Ni, Cr, Zn, V, Pb, Cd, and Co, and alkaline earth metals Ca, Mg and Ba in the collected urban surface dust during three seasons from nearly 20 locations in Faridabad industrial area are reported in Supplementary Table AT 2 in ppm units. The analysis report for some metals analyzed in the control standard BHVO-2, used to check the accuracy of the digestion method and precision of the analysis, is provided in Table 2 along with
Conclusions
The surface dust in the Faridabad industrial area shows variable contamination levels of metal ranging from low to extremely polluted. These changes are metal, space and time specific. The variations in the metals present in higher concentrations namely Al, Fe, Mn, and Ti and alkaline earth metals Ca and Mg show limited variations and lower abundances compared to UCC probably due to silica dilution effect; only Fe content in samples shows enrichment over UCC and seasonal changes. The other
Acknowledgements
Authors are thankful to two anonymous reviewers for their critical comments and help in improving the quality of the MS. Dr. J. K. Tripathi is acknowledged for his help in metal analysis on ICP-OES. AKP acknowledges the financial support received through JNU-UGC fellowship during this work.
References (47)
- et al.
Heavy metal pollution of coalmine-affected agricultural soils in the northern part of Bangladesh
J Hazard Mater
(2010) - et al.
Source, distribution and variability of airborne trace metals in La Plata City area, Argentina
Environ Pollut
(2001) - et al.
Chemical fractionation and translocation of heavy metals in Canna indica L grown on industrial waste amended soil
J Hazard Mater
(2008) - et al.
Assessment of trace metal distribution and contamination in surface soils of Hong Kong
Environ Pollut
(1997) - et al.
Spatial and chemical patterns of size fractionated road dust collected in a megacitiy
Atmos Environ
(2011) - et al.
Urban geochemistry: a study of the influence of anthropogenic activity on the heavy metal content of soils in traditionally industrial and non-industrial areas of Britain
Appl Geochem
(1996) - et al.
Head and neck cancer due to heavy metal exposure via tobacco smoking and professional exposure: a review
Toxicol Appl Pharmacol
(2010) - et al.
Lead content in household paints in India
Sci Total Environ
(2008) - et al.
Heavy metal contamination of urban soils and street dusts in Hong Kong
Appl Geochem
(2001) - et al.
Metal sorption on soils as affected by the dissolved organic matter in sewage sludge application
J Hazard Mater
(2007)