The Karnaphuli, a major river of Bangladesh, located off the coast of Chittagong in the Bay of Bengal is largely exposed to the heavy metal pollutants, which may be toxic to humans and aquatic fauna. The estuary is a striking example of a site where human pressure and ecological values collide with each other. In spite of being a major supplier of fish food for local community, there has been no study carried out to date to assess the potential human health risk due to heavy metal contamination in the fish species from this estuary. Therefore, the aim of present study was to assess bioaccumulation status and the potential human health risk evaluation for local consumers. Six commercially important fish species, Apocryptes bato, Pampus chinensis, Hyporhamphus limbatus, Liza parsia, Mugil cephalus, and Tenualosa toil from the Karnaphuli River estuary were collected to analyze heavy metals concentration level. Heavy metals As, Pb, Cd, Cr and Cu were detected from the samples using inductively coupled plasma mass spectrometry (Model: ELAN9000, Perkin-Elmer, Germany). The hierarchy of the measured concentration level of the metals was as follows: Pb (mean: 13.88, range: 3.19 - 6.19) > Cu (mean: 12.10, range: 10.27 - 16.41) > As (mean: 4.89, range: 3.19 – 6.19) > Cr (mean: 3.36, range: 2.46 – 4.17) > Cd (mean: 0.39, range: 0.21 - 0.74). The Fulton’s condition factor denoted that organisms were particularly in better ‘condition’ and most of the species were in positive allometric growth. The Bioaccumulation factors (BAFs) observed in the species of the contaminants were organized in the following ranks: Cu (1971.42) > As (1042.93) > Pb (913.66) > Cr (864.99) > Cd (252.03), and among all the specimens, demersal fish, A. bato corresponded to the maximum bio-accumulative organism. Estimated daily intake (EDI), target hazard quotient (THQ) and carcinogenic risk (CR) assessed for human health risk implications suggest that the values are within the acceptable threshold for all sorts of consumers. Hence none of them would experience non-carcinogenic and carcinogenic health effect for the ingestion of the fishes. However, children are shown to be largely susceptible than adults to non-carcinogenic and carcinogenic health effect due to the consumption of fish. Therefore, an appropriate guidlines and robust management measures needed to be taken to restore the estuarine health condition for greater benefit of the quality of fish products for local consumption. Graphical

This study aimed to examine the role and impact of social media on the knowledge of the COVID-19 pandemic in Bangladesh through disseminating actual changes in health safety, trust and belief of social media’s coverage statistics, isolation, and psychological numbness among students. This study used a cross-sectional design in which a quantitative approach was adopted. Data from an online survey were collected in a short period of time during the early stages of COVID-19 to determine the relationship between social media activity and knowledge of the COVID-19 pandemic with accuracy. A total of 189 respondents were interviewed using structured questionnaires during the onset of the COVID-19 outbreak in Bangladeshi university students. Exploratory factor analysis (EFA) and path analysis were performed. Out of 189 respondents, about 80% were aged between 16 and 25 years, of which nearly 60.33% were students. This study explored four factors—knowledge and health safety, trust in social media news, social distancing or quarantine, and psychological effect—using factor analysis. These four factors are also found to be positively associated in path analysis. Validation of the model was assessed, revealing that the path diagram with four latent exogenous variables fit well. Each factor coefficient was treated as a factor loading (β = 0.564 to 0.973). The results suggested that the measurement models using four elements were appropriate. The coefficient of determination was 0.98, indicating that the model provided an adequate explanation. Social media is transforming the dynamics of health issues, providing information and warnings about the adverse effects of COVID-19, having a positive impact on lockdown or quarantine, and promoting psychological wellness. This comprehensive study suggested that social media plays a positive role in enhancing knowledge about COVID-19 and other pandemic circumstances.