Carcinogenic effect of potential toxic metals in school children through contaminated drinking water around the industrial area of Pakistan

Due to papulation increase in Pakistan the demand of drinking water increased day by day. After the industrial grooming the wastewater producing harmful effect on the surrounding area of industries and drinking water contamination increased. Pakistan is on 82 amongst the 125 countries of the word having drinking water problem. Different parameter set by World Health Organization (WHO) and Pakistan Environmental Protection Agency (Pak-EPA) of hazard dimension index (HD) and Lifetime Cancerogenic risk Calculation (LFCR) of Potentially toxic metals that are As, Cd, Cr, Ni, Pb (PTMs) are higher, and the school age children are under high risk of cancer. All the drinking constraints set by regulating authority is fully neglected by inopportune human process by solid waste dumping and houses and industrial disposal with any proper treatment. This study discusses all the HD and LFCR parameter in three age group children, male and female through drinking water around the Hattar Industrial Estate (HIE) in Pakistan. In children and women more HD and LFCR thread than the adult man. The overall result shows that the HD risk is higher than the LFCR due to the PTMs in drinking water only HD is exceed from the limit of WHO and Pak-EPA. If there is no proper arrangement take place for the removal of As and PTMs from the industrial wastewater and drinking water than within few years all the population around the study area effected with different type of cancer.     

Distribution and Statistical Analysis of Leachable and Total Heavy Metals in the Sediments of the Suez Gulf

The concentrations of nine heavy metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pd and Zn) in the labile and total fractions of muddy and sandy sediment samples collected from twelve sites in Suez Gulf during April 1999 were studied to evaluate the pollution status of the Suez Gulf. The enrichment factors (EF) for each element were calculated. There are extremely high concentrations of Cd, Ni, Pb and slightly concentration of Cr and Cu in both muddy and sandy sediments. The concentration of Zn was moderately high and can be considered as seriously contaminate Metal pollution index (MPI) shows high values ranged between 46 to 156 and 40 to 232 for both sandy and muddy sediments, respectively. Concentrations of heavy metals were normalized against iron for total fraction in both of sandy and muddy sediments. Principal component analysis (PCA) was studied on the data matrix obtained and represented three-factor model explaining 92.22% for labile and 88.82% for total fractions of muddy sediment. The main source of contamination is the offshore oil fields and industrial wastes. This is largely a result of ineffective and inefficient operation equipment, illegal discharge of dirty ballast water from tankers and lack of supervision and prosecution of offenders.     

Potential Use of the Plant Antioxidant Network For Environmental Exposure Assessment of Heavy Metals in Soils

In recent years, awareness has risen that the total soil content of pollutants by itself does not suffice to fully assess the potential ecotoxicological risks involved. Chemical analysis will require to be complemented with biological assays in a multidisciplinary approach towards site specific ecological risk assessment (SS-ERA). This paper evaluates the potential use of the plants' antioxidant response to metal-induced oxidative stress to provide a sensitive biological assay in SS-ERA. To this end, plants of Phaseolus vulgaris were grown for two weeks on 15 soils varying in contamination level. Morphological parameters and enzymatic plant responses were measured upon harvest. Foliar concentrations of the (heavy) metals Al, Cu, Cd, Cr, Fe, Mn, Ni, Pb, Zn were also determined. Metal mobility in the soil was further assessed by determining soil solution and NH₄OAc extractable levels. In general more significant correlations were observed between plant responses and foliar metal concentrations or exchangeable/soluble levels than between plant responses and the total soil content. The study demonstrates the potential use of the plants' antioxidant defence mechanisms to assess substrate phytotoxicity for application in SS-ERA protocols. However, the system, based on calculation of a soil Phytotoxicity Index (PI), will require adaptation and fine-tuning to meet the specific needs for this type of environmental monitoring. Large variation was observed in phytotoxicity classification based on the various test parameters. The thresholds for classification of the various morphological and enzymatic response parameters may require adaptation according to parameter stress sensitivity in order to decrease the observed variation. The use of partial PI's (leaves and roots separately) may in addition increase the sensitivity of the system since some metals show specific effects in one of both organs only. Loss of biological functionality of enzymes, as was observed for ICDH in one of the more strongly contaminated soils, may also be recognized as an additional stress symptom when assigning phytotoxicity classification, whereas the current system only considers increasing enzymatic capacities. Other easily distinguishable parameters, which could be added to the current indexation are: failure to germinate and the incapacity to develop roots in the toxic substrate.Additional research will be required to determine the possible application range of soil properties for this biological assay and to further improve its performance in SS-ERA.     

The Effects of Small Dam Removal on the Distribution of Sedimentary Contaminants

With increasing concern over degradation of aquatic resources, issues of liability, and maintenance costs, removal of small dams has become increasing popular. Although the benefits of removal seem to outweigh the drawbacks, there is a relative paucity of studies documenting the extent and magnitude of biological and chemical changes associated with dam removal, especially those evaluating potential changes in contaminant inventories. In August and November of 2000, a run-of-the-river dam on Manatawny Creek (southeast Pennsylvania) was removed in a two-stage process. To assess the effects of dam removal on the contaminant redistribution within the creek, sedimentary concentrations of polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and trace metals (Cd, Cr, Cu, Ni, Pb, Zn) were evaluated prior to and several months after removal. Pre- and post-removal analyses revealed elevated and spatially variable concentrations of total PAHs (ranging from approximately 200 to 81,000 ng(g dry weight) and low to moderate concentrations of trace metals and PCBs. The concentrations of these sedimentary contaminants pre- versus post-removal were not significantly different. Additionally, though the impoundment received storm water run-off and associated contaminants from the adjacent city of Pottstown, the total inventory of fine-grain sediments in the impoundment prior to removal was very low. The removal of the low-level Manatawny Creek dam did not significantly redistribute contaminants downstream. However, each dam removal should be assessed on a case by case basis where the potential of sedimentary contaminant redistribution upon dam removal exists.     

Contaminant Exposure of Barn Swallows Nesting on Bayou D'Inde, Calcasieu Estuary, Louisiana, USA

Current and historical point source discharges, storm water runoff, and accidental spills have contaminated the water, sediment, and biota within the Calcasieu Estuary in southwestern Louisiana. In 2003, barn swallow (Hirundo rustica) eggs and nestlings were collected beneath two bridges that cross Bayou d′Inde, the most contaminated waterway within the Calcasieu Estuary. Samples were also collected from a bridge over Bayou Teche, a reference site in south central Louisiana. Polychlorinated biphenyl (PCB) concentrations in barn swallow eggs and nestlings were significantly higher at the downstream site on Bayou d′Inde (2.8 μ g/g PCBs in eggs and 1.5 μ g/g PCBs in nestlings) than at the other two sites (< 0.2 μ g/g PCBs in eggs and nestlings at both sites). Ethoxyresorufin-O-dealkylase activity in nestling livers was significantly higher at the downstream site on Bayou d′Inde (50 pmol/min/mg) compared to the other two locations (24 pmol/min/mg, each), probably because of exposure to PCBs. Polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran concentrations in eggs and polycyclic aromatic hydrocarbons in nestlings were at background concentrations at all sites. Trace element concentrations in barn swallow eggs and nestling livers were at background levels and did not differ among the three sites. A biomarker of DNA damage did not differ among sites.     

Characterization, Source Identification and Apportionment of Selected Metals in TSP in an Urban Atmosphere

To understand the metal distribution characteristics in the atmosphere of urban Islamabad, total suspended particulate (TSP) samples were collected on daily 12 h basis, at Quaid-i-Azam University campus, using high volume sampler. The TSP samples were treated with HNO₃/HClO₄ based wet digestion method for the quantification of eight selected metals; Fe, Zn, Pb, Mn, Cr, Co, Ni and Cd by FAAS method. The monitoring period ran from June 2001 to January 2002, with a total of 194 samples collected on cellulose filters. Effects of different meteorological conditions such as temperature, relative humidity, wind speed and wind direction on selected metal levels were interpreted by means of multivariate statistical approach. Enhanced metal levels for Fe (930 ng/m³), Zn (542 ng/m³) and Pb (210 ng/m³) were found on the mean scale while Mn, Cr, Co and Ni emerged as minor contributors. Statistical correlation study was also conducted and a strong correlation was observed between Pb-Cr (r=0.611). The relative humidity showed some significant influence on atmospheric metal distribution while other meteorological parameters showed weak relationship with TSP metal levels. Regarding the origin of sources of heavy metals in TSP, the statistical procedure identified three source profiles; automobile emissions, industrial/metallurgical units, and natural soil dust. The metal levels were also compared with those reported for other parts of the world which showed that the metal levels in urban atmosphere of Islamabad are in exceedence than those of European industrial and urban sites while comparable with some Asian sites.     

Heavy metal contamination in surface sediments of Yangtze River intertidal zone: An assessment from different indexes

Surface sediments (0-5 cm) from 59 stations within the Yangtze River intertidal zone (YRIZ) were sampled for metal contamination analysis in April and August 2005. The concentrations ranged (in mg kg⁻¹ dry weight): Al, 40,803-97,213; Fe, 20,538-49,627; Cd, 0.12-0.75; Cr, 36.9-173; Cu, 6.87-49.7; Mn, 413-1,112; Ni, 17.6-48.0; Pb, 18.3-44.1; and Zn, 47.6-154; respectively. Among the 59 sampling stations, enrichment factors (EF) indicate enrichment of Cd (52 stations), Cr (54 stations), Cu (5 stations), Ni (26 stations), Pb (5 stations) and Zn (5 stations). Geoaccumulation indexes (I_geo) also suggest individual metal contamination in localized areas. This study indicates that Cd, Cr and Ni enrichment in the YRIZ sediment is widespread whereas Cu, Mn, Pb and Zn enrichment is localized or nonexistent. Factor and cluster analyses indicate that Cd is associated with total organic carbon whereas Cu, Cr, Ni, Pb and Zn have a close association with Mn.     

Bioaccessibility of metals in soils and dusts contaminated by marine antifouling paint particles

Fragments of antifouling paint and environmental geosolids have been sampled from the island of Malta and analysed for total and bioaccessible metals. Total concentrations of Ba, Cd, Cu, Pb, Sn and Zn were two to three orders of magnitude higher in spent antifouling composites relative to respective values in background soils and road dusts. Paint fragments were visible in geosolids taken from the immediate vicinity of boat maintenance facilities and mass balance calculations, based on Ba as a paint tracer, suggested that the most contaminated soils, road dusts and boatyard dusts contained about 1%, 7% and 9%, respectively, of antifouling particles. Human bioaccessibilities of metals were evaluated in selected samples using a physiologically based extraction technique. Accessibilities of Cd, Cu, Pb and Zn in the most contaminated solids were sufficient to be cause for concern for individuals working in the boat repair industry and to the wider, local community.     

Adsorption of lambda-cyhalothrin and cypermethrin on two typical Chinese soils as affected by copper

Background, aim, and scope  Pesticides and heavy metals pollution in soil environment has become a serious problem in many countries including China. Repeated applications of bordeaux mixture (a blend of copper sulfate and calcium hydroxide) and pyrethroid (Pys) insecticides have led to elevated copper (Cu) and Pys concentrations in vineyard surface soils. However, few studies focused on the interaction of Pys and heavy metals in the soil environment. Our previous studies had indicated the combined effect of cypermethrin (CPM) and Cu on soil catalase activity. Also, we had suggested that the addition of Cu could catalyze photo-degradation of CPM and lambda-cyhalothrin (λ-CHT) in aqueous solution and restrain their degradation in soil. To better understand the potential influence of Cu on the fate of Pys in the soil environment, the aim of the present work was to examine the effect of Cu on the adsorption of λ-CHT and CPM on two typical Chinese soils with different soil characteristics, which was one of the key processes controlling the fate of Pys, and to provide more information about the potential ecological risk of chemicals on the soil ecosystem. Fourier transform infrared and point charges analysis using the MOPAC program of the Gaussian system were also used to reveal the probable adsorption mechanism of λ-CHT and CPM on soils. Materials and methods  Two vineyard soils with different properties were chosen as experimental samples. They were sampled from 0 to 10 cm, dried, and sieved to 2 mm. Each soil was spiked with copper sulfate solution to obtain the following total soil Cu concentrations: 100, 200, 400, 800, and 1,600 mg·kg⁻¹. The treated soils were incubated for 2 weeks and then dried at 20°C. For each soil sample and at each soil Cu concentration, the adsorption of λ-CHT and CPM was measured using a batch equilibrium method. The concentration of λ-CHT was determined by HPLC, and the amount of λ-CHT and CPM adsorbed by the soil sample at equilibrium was determined by the difference between the initial and equilibrium concentrations in solution corrected by the blank adsorption measurement. Results  Without the addition of Cu, the adsorption of λ-CHT and CPM on Black soil is greater than that on Red soil, while the adsorption of λ-CHT on both soils is significantly stronger than that of CPM. As the soil Cu concentration increased from 19 (or 18; background) to 1,600 mg·kg⁻¹, the adsorption coefficient (K _d) of λ-CHT decreased from 12.2 to 5.9 L·kg⁻¹ for Red soil, and from 26.1 to 16.8 L·kg⁻¹ for Black soil, whereas the CPM adsorption coefficient in both soils decreased nearly by 100% (K _d decreased from 9.4 to 0.2 L·kg⁻¹ for Red soil and from 16.2 to 0.5 L·kg⁻¹ for Black soil). Discussion  Pys adsorption is a surface phenomenon which depends on the surface area and the organic matter content. Thus, the Black soil, having higher organic matter and greater surface area than that of the Red soil, show greater adsorption affinity to λ-CHT and CPM. In our study, the different adsorption affinity of the two Pys was obtained, which was probably attributed to differences with respect to their physical–chemical properties. Further comparison upon the two Pys was conducted. The point charges of halogen atoms in the λ-CHT and CPM were calculated, the differences of which probably lead to the fact that λ-CHT has a stronger binding capacity to soils than CPM. Also, FTIR spectra show that competitive adsorption occurs between CPM and Cu for the same adsorption sites, which is responsible for the obtained suppression of CPM adsorption affected by Cu. Conclusions  Lambda-cyhalothrin shows a significantly stronger adsorption than cypermethrin on both soils. This phenomenon may be due to several reasons: (1) λ-CHT has lower solubility and a higher octanol–water partition coefficient value than CPM; (2) λ-CHT consists of specific isomers, whereas CPM is mixtures of eight different isomers; (3) the chlorine and fluorine atoms in the λ-CHT have a negative point charge, whereas the chlorine atoms in the CPM have a positive point charge. As the soil Cu concentrations increased from 19 (or 18) mg·kg⁻¹ to 1,600 mg·kg⁻¹, the adsorption coefficient of λ-CHT and CPM decreased on both soils. This is mainly due to a competition between Cu and Pys for occupying the adsorption sites on soils. The information from this study have important implications for vineyard and orchard soils, which often contain elevated levels of Cu and Pys. These results are also useful in assessing the environmental fate and health effect of λ-CHT and CPM. Recommendations and perspectives  It is important for environmental scientists and engineers to get a better understanding of soil–metal–organic contaminant interactions. However, pesticide adsorption involves complex processes, and shortcomings in understanding them still restrict the ability to predict the fate and behavior of pesticide. Therefore, considerable research should be carried out to understand the mechanism of interaction between Pys and heavy metal on soils clearly.     

Food alert patterns for metal contamination analyses in seafoods: Longitudinal and geographical perspectives

The aims of this study are to explore metal contamination in food with respect to variations in: i) the levels found over a period of eleven months and/or ii) by food types; and iii) to report patterns in reporting between countries. The frequencies of reported cases of metal ion contamination were ≤ 25% of total food alerts with notable increases between June and October. The alerted food products were dominated by seafood, where the majority were due to Mercury contamination and were made by EU member states with Italy making 57 of the 102 reports. The contaminated seafoods originate in thirty two countries with only Spain producing over 10 contaminated seafood products with a total of 47. In conclusion, this analysis highlights the main detector and transgressor nations along with the seafood and metal types that lead to alerts owing to high levels of contamination.