Implementation of water hyacinth (Eichhornia crassipes) and water lettuce (Pistia stratiotes) in the re-treatment of conventionally treated pharmaceutical wastewater: a case study of Radiant Pharmaceuticals Limited, Dhaka, Bangladesh.

Since Bangladesh already has robust pharmaceutical industries, nearly all companies owned effluent treatment plant (ETP) facilities to improve the quality of wastewater. Water retreatment utilizing affordable, accessible, and environmentally sustainable techniques have not yet been thoroughly investigated. In this study, the potential of water hyacinth and water lettuce was investigated at three different concentrations: 50% of total volume coverages (1000 g macrophytes/2000 ml water), 75% of total volume coverages (1500 g macrophytes/2000 ml water), and 100% of total volume coverages (2000 g macrophytes/2000 ml water) on the post-treated ETP's wastewater for 3 weeks in a mesocosm environment. Heavy metals, such as chromium (Cr) and nickel (Ni) along with physicochemical parameters (pH, EC, TDS, DO, and BOD5) were measured after 7 days intervals. Results indicated that water hyacinth was considerably more efficient than water lettuce at removing many factors, including metals. Water hyacinth was able to remove 79.15% of nickel and 92.97% of chromium while also increasing DO and EC by 36.72% and 14.59%, respectively, at 100% of total volume coverages. On the other hand, 100% of the total volume coverage of water lettuce decreased the pH, TDS, and BOD5 readings by 6.70%, 31.62%, and 87.61%, respectively. With each treatment, the water quality significantly improved over the control. The findings suggest that the pharmaceutical industries may improve the quality of their treated wastewater even more by integrating phytoremediation technology with traditional ETP facilities.

Emerging small-scale textile industries in residential areas of Mirpur, Dhaka City, Bangladesh: an assessment of the discharged wastewater quality and potential impacts.

The textile industries in Bangladesh are establishing remarkable opportunities for the financial growth of Bangladesh but the rapid and unplanned expansion of small-scale textile industries in residential areas has resulted in alarming environmental concerns. To examine the current pollution scenario in Dhaka City, Bangladesh generated from small-scale textile industries in residential areas, a study was conducted in Dhaka North City Corporation, particularly in Mirpur Sect. 7 and the Mirpur Shialbari area. Wastewater samples were collected from eight textile wet processing industries to assess the physio-chemical parameters of the samples. The investigation discovered that just two companies' wastewater samples (Industry 1 and 3) met the national standard set by the Department of Environment (DoE), Bangladesh as only these two sectors have Effluent Treatment Plants (ETPs) while the wastewater quality in the other industries (Industry 2, 4, 5, 6, 7, and 8) was unsatisfactory, indicating serious violations of the law. The results of the study will aid government policymakers in developing serious implementation strategies to prevent the discharge of untreated wastewater from small-scale companies in residential areas.