In this study, we evaluated the level of trace metals in the soil of heavily loaded tannery and battery industry area on the bank of the Buriganga River, Dhaka, Bangladesh in order to investigate their translocation to the locally grown vegetables and potential health risk of the local consumers. Concentrations of various metals in agricultural soil and in a number of vegetables such as; Red amaranth (Amaranthus cruentus), Spinach (Spanacia oleracea), Jute leaf (Corchorus capsularies), Bottle Gourd (Lagenaria siceraria), Mustard green (Brassica juncea) and Water spinach (Impomoea aquatica) were determined by atomic absorption spectrometry. The content of chromium (Cr), nickel (Ni), copper (Cu), zinc (Zn), cadmium (Cd), and lead (Pb) in the soil was around 500, 50, 50, 40, 0.8 and 200 mg/kg, respectively. Cr and Pb were found in the locally grown vegetables around 20 and 0.5 mg/kg respectively, which are higher than the permissible limit of them (2 mg/kg for Cr and 0.3 mg/kg for Pb) in vegetables as recommended by FAO/WHO and the data confirm the translocation of the metals from the soil to the vegetables. Hazard index value of all the vegetables considered was above 1, which indicates that the people could experience severe health risk due to consumption of any of those vegetables. Total cancer risk (TCR) value was obtained for Cr, Ni and Pb content in the local vegetables and it was observed that the value was around 1 × 10 −3 for all of the sample vegetables. The high TCR values (higher than the USEPA threshold level of 1 × 10 −6 ) indicate that there is a potential cancer risk due to intake of vegetables grown in that area.

Speaking English is a part of the daily academic life of the EFL learners at the undergraduate level of the major English programs in Bangladesh. This practice sometimes creates many problems for first-year undergraduate public and private university students. Despite its importance, sufficient data about the problems Bangladeshi university students face in speaking English was not found. To investigate the problems of speaking faced by the undergraduate students, the current study applied mixed methods, and eighty-eight students and four teachers from four universities participated in it. The result shows that both public and private university students with English majors face a lot of problems communicating in English. However, this study has found that public university students are slightly more competent in English and face fewer problems than private university students. The participants expressed different insights on the roles of curriculum, teaching techniques, and individual institutions to overcome the students' weakness in English speaking skills. Finally, the study puts forward some very specific recommendations on the basis of the findings for the concerned stakeholders.

The tanneries release a substantial amount of trivalent chromium with wastewater that bring about serious environmental pollution problem and health hazards without proper treatment. Therefore, the chromium concentration should be kept permissible in tannery effluent. In this study, the dried Moringa stenopetela seed was used as bio-adsorbent for the removal of Cr(III) from tannery effluent. Different adsorption parameters viz. pH, adsorbent dosage, initial chrome concentration, etc. were studied for optimizing the adsorption process. The sorption mechanism was described by various isotherm models and physicochemical parameters like turbidity, conductivity and TDS were also tested after treatment. The analyses showed that the percentage of Cr(III) removal (82.93%) was obtained at pH 3, adsorbent dosage 20g(mg/l), initial concentration 1123.3mg/l, for contact time 12hours at ambient temperature. The adsorption process followed Langmuir isotherm model. Additionally, the reduction in physicochemical parameters e.g. turbidity (67.68%-72.70%), conductivity (72.88%-80.99%) and TDS (71.96%-83.33%) was found satisfactory and the values were closed to the permissible limit set by DoE. Therefore, dry Moringa stenopetela seeds can be successfully used as a low-cost tannery effluent treatment agent to reduce the environmental threats caused by harmful tannery effluents.

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During the past decades, many conventional technologies of wastewater treatment have been utilized but they are ineffective in removing recently emerging substance of concern such as pharmaceuticals, pesticides, personal care...