Intense urbanization, large scale industrialization and unprecedented population growth in the last few decades have been responsible for lowering environmental quality. Soil contamination with metals is a serious concern due to their toxicity and ability to accumulate in the biota. The present work assessed the heavy metal contamination of agricultural soil in the close vicinity of the Dhaka Export Processing Zone (DEPZ) in both dry and wet seasons using different indices viz., index of geoaccumulation (I geo ), contamination factor (C ), degree of contamination (C ), modified degree of contamination (mC d ) and pollution load index (PLI). Samples were collected from the surface layer of soil and analyzed by Atomic Absorption Spectrophotometer (AAS). The trend of metals according to average concentration during the dry and wet seasons was As > Fe > Hg > Mn > Zn > Cu > Cr > Ni > Pb > Cd and As > Fe > Mn > Zn > Hg > Cu > Ni > Cr > Pb > Cd, respectively. Because of seasonal rainfall, dilution and other run-off during the wet season, metals from the upper layer of soil were flushed out to some extent and hence all the indices values were lower in this season compared to that of the dry season. I geo results revealed that the study area was strongly and moderately contaminated with As and Hg in the dry and wet seasons respectively. According to C , soil was classified as moderately contaminated with Zn, Cr, Pb and Ni, considerably contaminated with Cu and highly OPEN ACCESSAppl. Sci. 2012, 2 585 contaminated with As and Hg. The general trend of the mean C was Hg > As > Cu > Zn > Ni > Cr > Pb > Fe > Mn > Cd and As > Hg > Cu > Cd > Zn > Ni >Pb > Fe > Mn in dry and wet seasons, respectively. The mC f values in the dry and wet seasons were 575.13 and 244.44 respectively indicating an ultra high degree of contamination. The C d values in both seasons were associated with a very high degree of contamination. PLI results indicated immediate intervention to ameliorate pollution in both seasons. The main sources of metals included effluents from wastewater treatment plants, treated and untreated wastewater from surrounding industrial establishments as well as agricultural activities. Protecting the agricultural soil is a formidable challenge in the study area, which requires modernization of industries, thereby improving the recovery and recycling of wastewater. Indices analysis presented in the present work could serve as a landmark for contemporary research in toxicology.

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The present research has been performed on black pepper of two cultivars to evaluate their nutritional quality and safety issue on the basis of proximate, chemical and pharmacological properties. The proximate results were compiled with the standard USDA limits. K, Ca, Mg, Na, Fe, Al and Se were detected as major elements, whereas the toxic elements were found within the recommended limit. The GC‐MS analysis of the essential oils showed the presence of δ‐3‐carene (32.61%) as the major component in Kerala cultivar whereas β‐caryophyllene (18.39%) was the major components in Indigenous cultivar. The IC50 values of DPPH antioxidant activity of the essential oils were found to be 44.16 and 22.88 mg/mL in Indigenous and Kerala cultivars, respectively. The antimicrobial activity of the essential oils showed good activity in both cultivars. The LC50 values of the brine shrimp cytotoxic activity were 1.03 and 1.21 μg/mL in Indigenous and Kerala cultivars, respectively. Practical applications Spice quality is an important issue in the food industries as well as export markets. Due to the toxicological effect of imported spices, much attention has been paid to the safety issue especially on cytotoxicity and toxic metal contaminations. The present study reveals that both cultivars possess rich amount of nutritional components, essential minerals, phyto and flavouring components in their essential oils and recommended level of toxic elements as well as decent antioxidant and antimicrobial properties. This study promises to scaffold a new window for exportation of quality spice and confer potential for use in food, nutraceutical and pharmaceutical industries.

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Heavy metal pollution in agricultural soils and food crops around the ship breaking area is of great environmental and human health concern. In this work, we have spectroscopically determined the concentrations of Cd, Pb, Fe, Mn, Zn, Cr, Cu, and Ni in agricultural soils and commonly consumed vegetables, fruits, and rice grain collected from the Sitakunda ship breaking area of Chittagong, Bangladesh, in order to evaluate their contamination levels and probable human health risk with a multivariate statistical approach. Multivariate analyses such as principal component analysis and cluster analysis of the analytical data indicate a significant metal contamination in the samples which could be attributed to industrial activities such as ship breaking. The results of soil contamination evaluation indices such as enrichment factor, geo-accumulation index, and contamination factor demonstrated that the soils around the ship breaking area are mainly contaminated by Cd, Pb, Zn, and Cu while food crops were mostly contaminated by Zn, Cr, and Cu. The Pb contaminated the olive and teasle gourd while Cd contamination in rice grain was at the threshold limit for health hazard. Mn was slightly accumulated in banana. Transfer coefficient values of Cd, Zn, and Cu for almost all food crops were higher than other metals, and Cd showed the highest transfer. Estimated daily intake values for Ni exceeded the standard limit (1.3 μg kg −1 day −1). Target hazard quotient values of Cu, Zn, Pb, and Cd indicate that the local inhabitants who consume the contaminated food crops are being exposed to potential health risks.

Textile industries release huge amount of effluents to aquatic systems, which contain toxic and hazardous pollutants degrading the environment. A laboratory scale study was conducted to characterize physicochemical parameters of local textile industrial effluents and evaluate their impact on aquatic macrophytes and algae. Total suspended solids (TSS) and total dissolved solid (TDS) was found 100 to 336 mg/L and 1856 to 4356 mg/L, respectively. The recorded pH was 9.6 to 11.2 and temperature 40.5 to 43°C. Dissolved oxygen (DO), biological oxygen demand (BOD) and chemical oxygen demand (COD) was recorded 0.11 to 0.5, 151.24 to 299.1 and 652.8 to 2304 mg/L, respectively. Electrical conductivity (EC) was monitored 2210 to 6020 μs/cm; salinity was found 1.1 to 3.3 ‰, and color 1890.75 to 5625 PCU. Zinc (Zn), cadmium (Cd), copper (Cu) were 0.0838 to 0.596, 0.0 to 0.0006, 0.018 to 0.1727 ppm, respectively. Except heavy metals concentrations all of the physicochemical parameters were found beyond the standard limit set by department of Environment (DoE). Textile industrial effluents showed the toxic effects on aquatic macrophytes and algae, as aquatic macrophytes could hardly survive 2 days on textile effluents and noticeable reduction of algal concentration was found when grown on textile effluents. Key words: Textile effluents; Toxic effects; Physicochemical parameter; Aquatic macrophytes; Algae DOI: 10.3329/bjsir.v45i1.5187 Bangladesh J. Sci. Ind. Res. 45(1), 79-84, 2010

Poultry is one of the major protein sources for people in Bangladesh. It is a promising sector. It requires large scale feed production activities. There are various sources of raw materials for poultry feed production. In many ways these sources can be associated with anthropogenic heavy metal pollution. It is better to monitor any probable propagation of heavy metals into the food chain through the final feeds rather than the various raw materials for feeds. Three widely used feedsUsha, Fresh, and Saudi-Bangla feeds were selected for the study. Cadmium, lead, arsenic, mercury, selenium, chromium, manganese, nickel, copper, and zinc contents of all samples were measured. The detected maximum and minimum concentrations of these elements were found to be: 0.1852 ppm and 0.0232 ppm for cadmium, 20.6498 ppm and 0.6019 ppm for lead, 0.7640 ppm and 0.0069 ppm for arsenic, 0.0579 ppm and 0.0116 ppm for mercury, 0.0347 ppm and 0.0069 ppm for selenium, 5.7875 ppm and 0.0926 ppm for chromium, 302.2001 ppm and 0.0695 ppm for manganese, 5.1625 ppm and 0.0125 ppm for nickel, 37.5725 ppm and 0.0463 ppm for copper, and 422.3023 ppm and 0.0232 ppm for zinc. The "Poultry Feed Reference Standards, February 2002", prepared by Ministry of Fisheries and Livestock, Govt. of the People's Republic of Bangladesh contains no standards for the heavy metals as contaminants into poultry feeds which demands immediate attention.

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