The color which is obtained from the leaves of Henna, that is, Lawsonia inermis L., is used frequently in hair coloring. It is the chemical lawsone that is responsible for the reddish brown color. Its content makes it a substantive dye for dyeing the textile materials. This work concerns with the extraction and purification of natural dyestuff from a plant Lawsonia inermis L. and dyeing of cotton and silk fabric in exhaust dyeing method. The dye portion is isolated from the total extract by column chromatography and is evaluated by dyeing cotton and silk under different dyeing conditions. The color strength and fastness properties of the dye are undertaken by changing mordant and techniques of mordanting. The changes of colors have been noticed by using different types of mordant. The dye exhaustion percentage, wash, rubbing, and light fastness results reveal that the extract of henna can be used for coloration of cotton and silk fabric.

The textile and tannery industry in Bangladesh is liable for polluting the soil and water body owing to the discharge of untreated effluents. They use enormous amounts of water, chemicals, and colorants for processing textile and leather products and release a complex mixture of organic and inorganic pollutants and metal contents, which negatively impact the environment. The main objective of this research was to study the deleterious impact of untreated textile and leather effluents on the environment in Bangladesh. For this purpose, textile and leather effluents were collected from industries during discharging after processing. Parameters, such as BOD, COD, pH, TDS, TSS, TH, Turbidity, conductivity, alkalinity, Dissolved Fe, metal contents, etc., were tested to determine the characteristics of the effluents. Moreover, the impact of these effluents on tree plants as well as on fishes was observed over 24 days. The results showed that the effluents contain extremely high values of BOD, COD, TDS, TSS, hardness, conductivity, alkalinity, silica from the recommended discharge limit. It was also observed that leather effluents cause a more harmful effect on the survival of fishes and trees due to the presence of high metal contents than textile effluents. The findings will help address this alarming situation in the ecosystem of Bangladesh and recommend immediate action to save the ecosystem from untreated discharges of industrial effluents.

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Pasur river is one of the largest rivers in the World heritage Sundarbans mangrove forest region of the southwestern part of Bangladesh. Due to lack of alternative sources, more than 1 million inhabitants living at the Pasur river basin area relies heavily on the river water for domestic, irrigation, and industrial purposes without proper and reliable information on the water qualities and contamination types. The study aimed at evaluating the suitability and sustainability for irrigation and consumption practices, the persuading hydrogeochemical techniques and quality of Pasur river water of Sundarbon region of Bangladesh were investigated. Sample's water was collected from six locations during pre-monsoon and post-monsoon seasons and assessed the suitability of drinking and irrigation application. The water quality index (WQI) was calculated to evaluate the suitability of drinking. WQI indicates that the river water samples during both the seasons are safe for drinking with a good category. Sodium percentage (Na%), Sodium adsorption ratio (SAR), magnesium hazard (MH), Residual sodium carbonate (RSC) were investigated to assess the feasibility for agricultural applications. Most of the indices, such as SAR, Na%, and RSC results recommend that the river water is safe for irrigation. A suggestion is made that MH in river water should be controlled for the use of water in irrigation. United States salinity laboratory (USSL) diagram and Wilcox diagram analysis also identified that river water as a usable category for irrigation purposes is feasible during both seasons.