Evaluation of physicochemical and trace metal qualities of rainwater in the south-eastern region of Bangladesh

Abstract

The chemical characteristics of rainwater in the south-eastern region of Bangladesh were investigated in this study in addition to identifying the potential sources of different precipitation constituents, which have often been unexplored or not well covered in the literature. Rainwater pH, major ions and trace metals were measured in samples collected from five different locations with different land-use patterns of the Chattogram Metropolitan area (CMA) during two rainy seasons. The results of this study showed variability in rainwater quality across the sites signifying site-specific influences. The mean concentration of all measured physicochemical parameters, ions and trace metals in rainwater samples was also found to be significantly lower compared with the drinking water quality standard of Bangladesh and WHO guidelines. The correlation matrix and principal component analysis (PCA) indicated that and originated from anthropogenic sources, while the average concentration of trace metals found in rainwater was exhibited in the following order: Zn>Cu>Fe>Cr>Mn>Pb>Cd. The findings of this study could be used as a reference to further investigate the influences of industrial, urban and agricultural emissions that regulate the chemical characteristics of the atmosphere in particular areas of study.

Evaluating knowledge, awareness and associated water usage towards hand hygiene practices influenced by the current COVID-19 pandemic in Bangladesh

“…The obtained value of KMO was 0.667 while that of Bartlett's sphericity test was less than 0.01 implying that the studied datasets were suitable for PCA ( IBM, 2021 ). PCA is the transformation of the original variables of a data set into a set of new and uncorrelated variables which are known as the principal components (PCs), and the process is widely used to lessen data and to extract a small number of dormant factors for analysing associations among the observed variables ( Bodrud-Doza et al, 2020 ; Hossen et al, 2021 ). A component having eigenvalues of smaller than one is considered as less significant, and therefore, such an observed variable could be disregarded ( Rahman et al, 2020 ).…”

Stormwater Harvesting from Roof Catchments: A Review of Design, Efficiency, and Sustainability

“…The identification of contaminants and the conditions in which they arise can help to develop rules, regulations, and maintenance recommendations for small-scale rainwater harvesting [26]. Common contaminants from roof runoff include zinc, copper, and iron [27], although their concentration can depend on the roofing materials, environmental factors, and rainfall characteristics [23].…”

“…Regarding roofing material, some studies showed that the quality of rainwater harvested from roof runoff was greatly affected by the materials used for roofing [13,27]. The concrete roof had a beneficial influence on hardness, EC, pH, and alkalinity compared to the other roof types [29].…”

“…Studies suggest that pollutants can build up on a roof over an extended dry period, causing pollutant concentrations to be higher. Eliminating ponding on the surface was found to be effective in minimizing the potential of microbiological contamination of the roof runoff [27,34]. Since rainwater is collected from rooftops, studies recommend choosing suitable roofing materials based on the intended application [35].…”