Soil heavy metal contamination in an industrial area: analysis of the data collected during a decade

Soil contamination by heavy metals has become a serious problem mainly because, above certain concentrations, all metals have adverse effects on human health. In particular, the accumulation of heavy metals in agricultural soils leads to elevated uptake by crops and affects food quality and safety. In this paper, we present the results of a study carried out over a decade for evaluating the impact of a new industrial settlement in an area geared to agriculture and livestock and far from urban sites. We focus our study on the bioavailable fraction of Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn in soil samples. Heavy metal concentrations in soil are analysed with both univariate and multivariate statistical procedures. The main goal of this paper is the development of a statistical procedure, based on a mix of multivariate analysis, able to compare field surveys carried out during different years and to characterize spatial and temporal changes in soil heavy metals concentrations.     

Soil contamination of heavy metals in the Katedan Industrial Development Area, Hyderabad, India

Studies on quantitative soil contamination due to heavy metals were carried out in Katedan Industrial Development Area (KIDA), south of Hyderabad, Andhra Pradesh, India under the Indo-Norwegian Institutional Cooperation Programme. The study area falls under a semi-arid type of climate and consists of granites and pegmatite of igneous origin belonging to the Archaean age. There are about 300 industries dealing with dyeing, edible oil production, battery manufacturing, metal plating, chemicals, etc. Most of the industries discharge their untreated effluents either on open land or into ditches. Solid waste from industries is randomly dumped along roads and open grounds. Soil samples were collected throughout the industrial area and from downstream residential areas and were analysed by X-ray Fluorescence Spectrometer for fourteen trace metals and ten major oxides. The analytical data shows very high concentrations of lead, chromium, nickel, zinc, arsenic and cadmium through out the industrial area. The random dumping of hazardous waste in the industrial area could be the main cause of the soil contamination spreading by rainwater and wind. In the residential areas the local dumping is expected to be the main source as it is difficult to foresee that rain and wind can transport the contaminants from the industrial area. If emission to air by the smokestacks is significant, this may contribute to considerable spreading of contaminants like As, Cd and Pb throughout the area. A comparison of the results with the Canadian Soil Quality Guidelines (SQGL) show that most of the industrial area is heavily contaminated by As, Pb and Zn and local areas by Cr, Cu and Ni. The residential area is also contaminated by As and some small areas by Cr, Cu, Pb and Zn. The Cd contamination is detected over large area but it is not exceeding the SQGL value. Natural background values of As and Cr exceed the SQGL values and contribute significantly to the contamination in the residential area. However, the availability is considerably less than anthropogenic contaminants and must therefore be assessed differently. The pre- and post-monsoon sampling over two hydrological cycles in 2002 and 2003 indicate that the As, Cd and Pb contaminants are more mobile and may expect to reach the groundwater. The other contaminants seem to be much more stable. The contamination is especially serious in the industrial area as it is housing a large permanent residing population. The study not only aims at determining the natural background levels of trace elements as a guide for future pollution monitoring but also focuses on the pollution vulnerability of the watershed. A plan of action for remediation is recommended.     

Heavy metal contamination of drinking water in Kamrup district, Assam, India

This study was undertaken to assess the heavy metal concentration of the drinking water with respect to zinc, copper, cadmium, manganese, lead and arsenic in Kamrup district of Assam, India. Ground water samples were collected from tube wells, deep tube wells and ring wells covering all the major hydrogeological environs. Heavy metals in groundwater are estimated by using Atomic Absorption Spectrometer, Perkin Elmer Analyst 200. Data were assessed statistically to find the distribution pattern and other related information for each metal. The study revealed that a good number of the drinking water sources were contaminated with cadmium, manganese and lead. Arsenic concentrations although did not exceeded WHO limits but was found to be slightly elevated. Copper and zinc concentrations were found to be within the prescribed WHO limits. An attempt has also been made to ascertain the possible source of origin of the metals. Positive and significant correlation existing between manganese with zinc and copper indicates towards their similar source of origin and mobility. In view of the present study and the level of heavy metal contamination, it could be suggested to test the potability of the water sources before using it for drinking purpose.     

Water-soluble species and heavy metal contamination of the petroleum refinary area,Jordan

The levels of lead, cadmium, copper, zinc, aluminum, chromium, and iron in street dust, soil, and plants in the Jordanian petroleum refinery were determined using flame and graphite-furnace atomic absorption spectrophotometry. Major cations (Li+, Na+, NH4+, K+, Mg2+, and Ca2+) and anions (F-, Cl-, NO3-, SO4(2-), and Br-) were also determined using suppression mode ion chromatography. Generally, higher levels of the heavy metals studied were found in street dust samples than in soil samples. On the other hand, except Cl-, and Li+ ions, other anions and cations showed higher concentrations in soil than in street dust samples. For plant samples, unwashed samples showed higher levels of heavy metals than their washed counterparts, indicating that dust fall is a source of heavy metal contamination.     

Assessment of heavy metal contamination in Candarli Gulf sediment, Eastern Aegean Sea

Concentrations of selected heavy metals (Fe, Mn, Ni, Cu, Zn, Pb, Hg, Cr, Al, and As) in surface sediments from 18 stations in the Candarli Gulf were studied in order to understand current metal contamination due to urbanization and economic development in Candarli region, Turkey. The sediment samples were collected by box corer in Candarli Gulf in 2009 to assess heavy metal pollution. Heavy metal concentrations in surface sediment varied from 1.62% to 3.60% for Fe, 0.38?C2.53% for Al, 173?C1,423 for Mn, 8?C100 for Ni, 3?C46 for Cu, 55?C119 for Zn, 16?C138 for Pb, 0.2?C6.3 for Hg, 16?C71 for Cr, and 11?C37 mg kg^???1 for As. This study showed that the concentrations of Mn, Ni, Zn, Pb, Hg, and Cr in the surface sediment layers were elevated when compared with the subsurface layers. Both metal enrichment and contamination factors show that Hg, Zn, and Pb contamination exists in the entire study area and contamination of other metals is also present in some locations depending on the sources.     

Heavy metal contamination in water, soil, and vegetables of the industrial areas in Dhaka, Bangladesh

Concentrations of Cu, Zn, Pb, Cr, Cd, Fe, and Ni have been estimated in soils and vegetables grown in and around an industrial area of Bangladesh. The order of metal contents was found to be Fe > Cu > Zn > Cr > Pb > Ni > Cd in contaminated irrigation water, and a similar pattern Fe > Zn > Ni > Cr > Pb > Cu > Cd was also observed in arable soils. Metal levels observed in different sources were compared with WHO, SEPA, and established permissible levels reported by different authors. Mean concentration of Cu, Fe, and Cd in irrigation water and Cd content in soil were much above the recommended level. Accumulation of the heavy metals in vegetables studied was lower than the recommended maximum tolerable levels proposed by the Joint FAO/WHO Expert Committee on Food Additives (1999), with the exception of Cd which exhibited elevated content. Uptake and translocation pattern of metal from soil to edible parts of vegetables were quite distinguished for almost all the elements examined.     

Ionic and heavy metal composition of respirable particulate in Madurai, India

Airborne particulate matter (PM₁₀) was collected for a period of 1 year at six locations in Madurai city, India. The chemical analyses on PM₁₀ samples were carried out for the estimation of heavy metals and ions using atomic absorption spectroscopy and ion chromatography respectively. The average PM₁₀ concentrations varied from 97.2 to 152.5 μg/m³, which were found to be below the Indian air quality standards. While industrial areas had the highest concentrations of heavy metals such as Fe, Zn and Cr and also the $\text{SO}_{4}^{2-}$ ions, traffic areas with relatively higher traffic densities in the city endured highest concentrations of Cd and the $\text{NO}_{3}^{-}$ ion. As gaseous pollutants serve as precursors of ionic particles in the atmospheric environment, gaseous pollution control is necessitated along with particulate with special reference to heavy metal and ion pollution abatement for the sustainable development of Madurai city.     

Statistical source identification of metals in groundwater exposed to industrial contamination

Levels of selected metals Na, Ca, Mg, K, Fe, Mn, Cr, Co, Ni, Cd, Pb and Mn were estimated by flame atomic absorption spectrophotometry in groundwater samples from Kasur, a significant industrial city of Pakistan. Salient mean concentration levels were recorded for: Na (211 mg/l), Ca (187 mg/l), Mg (122 mg/l), K (87.7 mg/l), Fe (2.57 mg/l) and Cr (2.12 mg/l). Overall, the decreasing metal concentration order was: Na > Ca > Mg > K > Fe > Cr > Zn > Co > Pb > Mn > Ni > Cd. Significantly positive correlations were found between Na–Cr (r = 0.553), Na–Mn (r = 0.543), Mg–Fe (r = 0.519), Mg–Cr (r = 0.535), Pb–K (r = 0.506) and Pb–Ni (r = 0.611). Principal Component Analysis and Cluster Analysis identified tannery effluents as the main source of metal contamination of the groundwater. The present metal data showed that Cr, Pb and Fe levels were several times higher than those recommended for water quality by WHO, US-EPA, EU and Japan. The elevated levels of Cr, recorded as 21–42 fold higher compared with the recommended quality values, were believed to originate from the tanning industry of Kasur.     

An assessment of heavy metal contamination in surface sediment using statistical analysis

The distribution and accumulation of heavy metals in the sediments, especially those nearest of wastewater discharges of south of Spain, were investigated. Sediment samples from 14 locations were collected and characterised for metal content (e.g. Ni, Cu, Zn, Cr, Pb, Mn, Cd and Hg), organic carbon, total nitrogen, total phosphorous, n-hexane-extractable material, carbonates and grain size. Concentration data were processed using correlation analysis and factor analysis. The correlation analysis of concentrations data showed important positive correlations among organic carbon, total phosphorus, Cu, Zn, Cd and Hg, otherwise weak correlations among Mn, Cr, Ni and CO₃ ^2???, indicating that these metals have complicated geochemical behaviours. The use of statistical factor analysis also confirmed these results. Sediments pollution assessment was carried out using geoaccumulation and metal pollution indexes (MPI₈). The results revealed that sediments of Cádiz bay and Sancti Petri channel were uncontaminated with the studied metals.     

Distribution of heavy metals in surface water of Ranipet industrial area in Tamil Nadu, India

Ranipet industrial area is about 120 km from Chennai on Chennai-Bangalore highway and is a chronic polluted area identified by Central Pollution Control Board of India. It is one of the biggest exporting centers of tanned leather in India. The total number of industries located in and around Ranipet town are 240 tanneries along with ceramic, refractory, boiler auxiliaries plant, and chromium chemicals. Studies were carried out to find out the contamination of surface water bodies due to industrial effluents. The results reveal that the surface water in the area is highly contaminated showing very high concentrations of some of the heavy/toxic metals like Cadmium ranging from 0.2 to 401.4 μg/l (average of 51.1 μg/l), Chromium 2.4–1,308.6 (average of 247.2 μg/l), Copper 2.1–535.5 μg/l (average of 95.5 μg/l), Nickel 1.6–147.0 μg/l (average of 36.7 μg/l), Lead 6.4–2,034.4 μg/l (average of 467.8 μg/l) and Zinc 20.8–12,718.0 μg/l (average of 3,760.4 μg/l). The concentration levels of these metals are much above the permissible limits in surface water and are health hazards especially for the people working in the tannery industries. It was observed that the people in the area are seriously affected and suffering from occupational diseases such as asthma, chromium ulcers and skin diseases. Distribution of metals, their contents at different locations, and their effects on human health are discussed in this paper.     

Source identification and assessment of sediment contamination of trace metals in Kogarah Bay,NSW, Australia

The distribution of trace metals (spatial and temporal) and sedimentary fractions were investigated to identify the concentrations and sources of trace metals within Kogarah Bay, NSW, Australia. A total of 59 surface sediments and six subsurface samples from core of the sediment were collected. The contamination factor and pollution load index indices used to evaluate environmental effects of trace metals. The study area was found to be uncontaminated with Cr and Ni, moderately contaminated with As and considerably contaminated with Cu, Zn and Pb. The concentrations of Cr and Ni were below both effect range low and effect range median, while As, Cu, Zn and Pb were slightly above effect range low. The highest concentrations of these trace metals such as Cu, Zn and Pb were found in the north, northwest and southeast of the bay, close to discharge points, stormwater outlets and around boatyards and watercrafts. The spatial distributions of metals were strongly related to muddy particles and organic matter. The temporal sediments of metals declined with increased sediment depth, which reflects accumulation of trace metals since European settlement in this area. Furthermore, the source of the trace metals was found to be stormwater outlets, gasoline fumes, boatyards and other human activities.     

Assessment of heavy metal status and identification of source in soils under intensive vegetable growing areas of Brahmaputra valley,North East India

Environmental Monitoring and Assessment - Evaporation is an important meteorological variable that has a great impact on water resources. In the current research, climatology data, and seasonal...     

Application of sequential leaching, risk indices and multivariate statistics to evaluate heavy metal contamination of estuarine sediments: Dhamara Estuary, East Coast of India

In the present study, concentration of some selected trace metals (Fe, Mn, Ni, Co, Pb, Zn, Cu, Cr and Cd) are measured in Brahmani, Baitarani river complex along with Dhamara estuary and its near shore. Chemical partitioning has been made to establish association of metals into different geochemical phases. The exchangeable fraction is having high environmental risk among non-lithogeneous phases due to greater potential for mobility into pore water. The metals with highest bio-availability being Cd, Zn and Cr. The metals like Mn, Zn, Cd and Cu represent an appreciable portion in carbonate phase. Fe–Mn oxides act as efficient scavenger for most of the metals playing a prime role in controlling their fate and transport. Among non-lithogeneous phases apart from reducible, Cr showed a significant enrichment in organic phase. Risk assessment code values indicate that all metals except Fe fall under medium-risk zone. In estuarine zone Cd, Zn, Pb and Cr are released to 32.43, 26.10, 21.81 and 20 %, respectively, indicating their significant bio-availability pose high ecological risk. A quantitative approach has been made through the use of different risk indices like enrichment factor, geo-accumulation index and pollution load index. Factor analysis indicates that in riverine zone, Fe–Mn oxides/hydroxides seem to play an important role in scavenging metals, in estuarine zone, organic precipitation and adsorption to the fine silt and clay particles while in coastal zone, co-precipitation with Fe could be the mechanism for the same. Canonical discriminant function indicates that it is highly successful in discriminating the groups as predicted.     

Seasonal variations of heavy metal contamination in river Gomti of Lucknow city region

The present study deals with the seasonal variations in the concentrations of heavy metals namely chromium, lead and mercury by using spectrophotometric methods. The water samples were collected at regular intervals from five selected sites of river Gomti in the pre-monsoon period (months of February-May) and the post monsoon period (months of October-January). The concentrations of chromium (VI) and mercury (II) were determined by using Genesys-10 UV-VIS Spectrophotometer while lead (II) concentrations were determined using Atomic Absorption Spectrophotometer, Perkin-Elmer 5000 model. The concentrations of all the three metals were found to be higher in the pre-monsoon period than in the post-monsoon period. The statistical analysis of the data was discussed in both the seasons in terms of mean, standard deviation and coefficient of variation.     

Inventory compilation and distribution of heavy metals in wastewater from small-scale industrial areas of Delhi, India

Delhi has the highest cluster of small-scale industries (SSI) in India. There are generally less stringent rules for the treatment of waste in SSI due to less waste generation within each individual industry. This results in SSI disposing of their wastewater untreated into drains and subsequently into the river Yamuna, which is a major source of potable water in Delhi, thus posing a potential health and environmental risk to the people living in Delhi and downstream. To study the quantity, quality and distribution of heavy metals in liquid waste from industrial areas, wastewater, suspended materials and bed sediments were collected from industrial areas and from the river Yamuna in Delhi. This study has also focused on the efficiency of production processes in small-scale industries in India. Heavy metals such as Fe, Mn, Cu, Zn, Ni, Cr, Cd, Co and Pb were detected using a GBC 902 atomic absorption spectrometer. The concentration of heavy metals observed was as follows: Fe 2-212, Mn 0.3-39, Cu 0.2-20, Zn 0.2-5, Ni 0.6-6, Cr 0.2-53, Cd 0.08-0.2, Co 0.013-0.55, Pb 0.3-0.7 mg L(-1) in wastewater; Fe 5842-78 000, Mn 585-10 889, Cu 206-7201, Zn 406-9000, Ni 22-3621, Cr 178-10 533, Co 17-114, Cd 13-141, Pb 67-50 171 mg kg(-1) in suspended material; and Fe 3000-84000, Mn 479-1230, Cu 378-8127, Zn 647-4010, Ni 164-1582, Cr 139-3281, Co 20-54, Cd 37-65, Pb 228-293 mg kg(-1) in bed residues. This indicates that SSI could be one of the point sources of metals pollution in the river system.     

Assessment of trace metal contamination in a historical freshwater canal (Buckingham Canal), Chennai, India

The present study was done to assess the sources and the major processes controlling the trace metal distribution in sediments of Buckingham Canal. Based on the observed geochemical variations, the sediments are grouped as South Buckingham Canal and North Buckingham Canal sediments (SBC and NBC, respectively). SBC sediments show enrichment in Fe, Ti, Mn, Cr, V, Mo, and As concentrations, while NBC sediments show enrichment in Sn, Cu, Pb, Zn, Ni, and Hg. The calculated Chemical Index of Alteration and Chemical Index of Weathering values for all the sediments are relatively higher than the North American Shale Composite and Upper Continental Crust but similar to Post-Archaean Average Shale, and suggest a source area with moderate weathering. Overall, SBC sediments are highly enriched in Mo, Zn, Cu, and Hg (geoaccumulation index (I_geo) class 4–6), whereas NBC sediments are enriched in Sn, Cu, Zn, and Hg (I_geo class 4–6). Cu, Ni, and Cr show higher than Effects-Range Median values and hence the biological adverse effect of these metals is 20%; Zn, which accounts for 50%, in the NBC sediments, has a more biological adverse effect than other metals found in these sediments. The calculated I_geo, Enrichment Factor, and Contamination Factor values indicate that Mo, Hg, Sn, Cu, and Zn are highly enriched in the Buckingham Canal sediments, suggesting the rapid urban and industrial development of Chennai Metropolitan City have negatively influenced on the surrounding aquatic ecosystem.     

Use of the land snail Helix aspersa for monitoring heavy metal soil contamination in Northeast Algeria

The objective of this study was to investigate the impact of anthropogenic activities on soil quality using the land snail Helix aspersa as a bioindicator. Soil samples and snails were collected from several sites in Northeast Algeria during the summer and winter of 2010. All of the sites were chosen due to their proximity to industrial factories—a potential source of soil pollution via heavy metal contamination. The concentration of heavy metals (Pb, Cd, Mn, and Fe) in soil samples was analyzed using atomic absorption spectrophotometry. Activity levels of glutathione S-transferase (GST) and acetylcholinesterase (AChE), indicators of oxidative stress and neurotoxicity, respectively, were measured in snails collected from each site. GST and AChE activity were found to vary between sites and by season. The highest levels of GST activity were registered during the summer at sites closest to potential sources of pollution. AChE activity levels also peaked during the summer with the highest values recorded at the site in El Hadjar. These increased levels of bioindicative stress response correlated with increasing metal concentration in soil samples collected at each site.