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Background: Vegetables are the main source of nutrients for the human being but the intake of contaminated vegetables causes several diseases. Therefore, the aims of this study were to examine heavy metals concentration in leafy, fruit and root vegetables and their growing soil in Mongla, Bangladesh; and to estimate the health risks (non-carcinogenic and carcinogenic) caused by heavy metal exposure through ingestion of vegetable using hazard quotient (THQ) and target cancer risk (TCR). Methods: United States Environmental Protection Agency (USEPA) deterministic approaches were used to assess the potential health risks to the human. Results: The average concentration of Fe, Cd, and Pb was 489.47, 0.48 and 8.15 mg/kg respectively, which was above the permissible limit recommended by WHO/FAO. Furthermore, THQ values for these metals and combined impacts of all metals (HI) were greater than the acceptable limit (1.0) which indicated a potential non-carcinogenic health risk. TCR values of Cd and Pb were greater than USEPA risk limit ( greater-than 10 -6); which exerts moderate to high carcinogenic risk to the human. Conclusion: The total health risk index showed that the consumption of vegetables from this study area poses a health risk and therefore regular monitoring of heavy metals is strongly recommended.

Surface water has become one of the most vulnerable resources on the earth due to deterioration of its quality from diverse sources of pollution. Understanding of the spatiotemporal distribution of pollutants and identification of the sources in the river systems is a prerequisite for the protection and sustainable utilization of the water resources. Multivariate statistical techniques such as Principal Component Analysis (PCA) and Factor Analysis (FA) were applied in this study to investigate the temporal and spatial variations of water quality and appoint the major factors of pollution in the Shailmari River system. Water quality data for 14 physicochemical parameters from 11 monitoring sites over the year of 2014 in three sampling seasons were collected and analyzed for this study. Kruskal-Wallis test showed significant (p < 0.01) temporal and spatial variations in all of the water quality parameters of the river water. Principal component analysis (PCA) allowed extracting the contributing parameters affecting the seasonal water quality in the river system. Scatter plots of the PCs showed the tidal and spatial variation within river system and identified parameters controlling the behavior in each case. Factor analysis (FA) further reduced the data and extracted factors which are significantly responsible for water quality variation in the river. The results indicate that the parameters controlling the water quality in different seasons are related with salinity, anthropogenic pollution (sewage disposal, effluents) and agricultural runoff in pre-monsoon; precipitation induced surface runoff in monsoon; and erosion, oxidation or organic pollution (point and non-point sources) in post-monsoon. Therefore, the study reveals the applicability and usefulness of the multivariate statistical methods in assessing water quality of river by identifying the potential environmental factors controlling the water quality in different seasons which might help to better understand, monitor and manage the quality of the water resources.

In this present study, the extracted oil from the mesocarp fibers was characterized by the determination of iodine, free fatty acid, ester and acid value found in a reasonable range which contained a remarkable amount of fatty acids. The Reichert-Meissl values were found zero indicating the lower rancidity properties of these oils. B. flabellifer crude oil contains lauric, tetradecanoic, palmitic, palmitoleic, octadecanoic, cis-9-oleic, linoleic, linolenic, docosanoic acid whereas the N. fruticans contains the same fatty acids with an extra arachidic, except palmitic acid. The phytochemical screening revealed the presence of tannin, phenolic, and flavonoid content for both samples. Antioxidant results showed that the IC50 for B. flabellifer was lower than N. fruticans suggesting that the B. flabellifer was more effective than N. fruticans as a preservative which might be due to the presence of phenolic and flavonoid contents that could be used as potential medicinal and preservative agents.

Water quality is the critical environmental determinant that influences the agricultural production and therefore, the economy that solely depends on its agricultural productions. Batiaghata Upazilla is one of the major crop productive areas of Khulna region and the agricultural production here largely depends on the natural water of the Shailmari River system around it. The present study was conducted to assess the suitability of this coastal river water for irrigational use. 66 water samples were collected during this study in three consecutive agricultural seasons, viz., pre-monsoon (22), monsoon (22) and post-monsoon (22) from 11 sampling stations within the river system considering the high (11) and ebb (11) tides for each station. Standard methods were followed throughout the study period for the collection of the samples and analysis of major physicochemical parameters (pH, EC, TDS, salinity, Na, K, Ca, Mg, Cl, HCO3, SO4, NO3 and PO4). Hydrocehmical characterization using Piper trilinear diagram shows that the water of the river system is Na-Cl dominated saline water type in pre-monsoon, whilst most of the samples of the river and the connected channel are characterized as fresh water of Ca-Mg-Na-HCO3 and Ca-Na-Mg-HCO3 types in monsoon and post-monsoon respectively. The calculated values of chemical indices like SAR, %Na, KI, PI and MH using the results of the analysed parameters indicate that the river water is chemically unsuitable for use in irrigation during pre-monsoon, while in the monsoon and post-monsoon the river water is within good to permissible limit for the use in the agricultural fields. However, high %Na, KI and MH values with high salinity of the channel water limit its use in agricultural applications in monsoon and post-monsoon. The USSL (United States Salinity Laboratory) diagram depicts that the river water is C4-S4 type with very high salinity and sodium content in pre-monsoon, while in other seasons the water is mostly C1-S1, C2-S1 or C2-S2 types (low to moderate salinity and sodium) in the river. Wilcox diagram shows that the river water is “suitable” for irrigation during monsoon and post-monsoon as the most of the samples range within “Excellent to Good” and “Good to permissible” categories, while it is “unsuitable” for crop irrigation during pre-monsoon when SAR (Sodium Adsorption Ratio) and EC (Electrical Conductivity) values of the water reach to their peaks.