Despite significant contributions to the national economy of Bangladesh, various urban developments, massive industrial and growing shipping activities are making the water of many urban rivers, including Karnaphuli River, extremely polluted. To find out the pollution sources and their possible health effects, 45 water samples were collected from 15 sampling stations. Investigation of six physicochemical parameters (pH, temperature, total dissolved solids, conductivity, salinity, and turbidity) through in-situ measurements and eight heavy metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) status using atomic absorption spectrophotometer (AAS) was carried out in this research. Both the physicochemical parameters and heavy metals exceeded the World Health Organization (WHO)’s permeable threshold limit. The calculated hazard quotient (HQ) and hazard index (HI) ingestion values indicate non-carcinogenic risk both for adults and children, but dermal exposure was within the safety limit. Carcinogenic risk analysis revealed that Cd could cause a risk of cancer in those using the river water for a long period. Spatial analysis and metal pollution index (MPI) results exhibit that downstream of the river water is more polluted than upstream of the river. Overall, the findings of this study imply that polluted water is a threat to human health and the results will also help to undertake proper management strategies and incorporate monitoring programs that study river water for the implementation of safety measures to protect human health.

As a result of the continuous evolution of microbial pathogens towards antibiotic-resistance, there have been demands for the development of new and effective antimicrobial compounds. Since the 1960s, the scientific literature has accumulated many publications about novel pharmaceutical compounds produced by a diverse range of marine bacteria. Indeed, marine micro-organisms continue to be a productive and successful focus for natural products research, with many newly isolated compounds possessing potentially valuable pharmacological activities. In this regard, the marine environment will undoubtedly prove to be an increasingly important source of novel antimicrobial metabolites, and selective or targeted approaches are already enabling the recovery of a significant number of antibiotic-producing micro-organisms. The aim of this review is to consider advances made in the discovery of new secondary metabolites derived from marine bacteria, and in particular those effective against the so called “superbugs”, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin resistant enterococci (VRE), which are largely responsible for the increase in numbers of hospital acquired, i.e., nosocomial, infections.

It is well understood that both untreated and partially treated wastewater comprise substantial amount of resources, which can be recovered and utilized for different purposes. Since Waste Water Treatment Plant (WWTP) is energy intensive and expensive, substantiating the WWTPs with Resource Recover Technologies (RRTs) will not only save a considerable amount of energy but also make the environment cleaner and safer. In line with this, this paper seeks to review several RRTS and to identify their limitations. Several effective nutrient recovery methods using both biota (e.g., microalgae, duckweed, aquatic macrophytes) and chemical processes (e.g., struvite precipitation and HAIX resin) are discussed in this study. The recovered nutrients can be used as fertilizer, animal feed and for production of protein rich by-products. In order to enhance the efficiency of nutrient recovery processes, several researchers suggest introducing hybrid system of nutrient recovery. On the other hand, biosolids, biogas, conserved heat, effluent flow, Microbial Fuel Cells (MFC), Microbial Electrolysis Cells (MEC) can potentially be employed to produce electricity and other forms of energy that can meet the demand of existing WWTPs. Moreover, the comparative analysis of these technologies in terms of advantages and disadvantages and their recovery potential has been discussed. The review analysis indicates that despite having limitations, several RRTs are being practiced mostly in developed world. Future research should focus on how to increase the efficiency of existing RRTs and identify innovative RRTs available in developing countries.