Groundwater Pollution in Bangladesh: A Review

Bangladesh relies mainly on groundwater for irrigation and drinking purposes. Groundwater, however, continuously polluted, is a major obstacle. Nowadays, Bangladesh is moving towards industrial revolution in a considerable speed. As part of this paper's attempt to analyze the groundwater pollution scenario in Bangladesh, specifically in the past two decades, about 100 articles, conference papers, and reports published in national and international journals and books were reviewed, as well as issues concerning pollution sources, health impact assessment, and future perspectives were discussed. The groundwater is contaminated by different contaminants, such as physico-chemicals, trace metals, and microbes. Human health is at great risk from arsenic (As) contamination; it is one of the biggest threats. The cancer risk and non-cancer risk of ingesting water are increased. On the other hand, a large number of peoples were affected due to waterborne diseases governed by microbial contamination. Geophysical and anthropogenic sources, the depth of wells, and geographical factors may influence groundwater pollution. It is recommended that policy makers should address the issue immediately and precautions should be taken wherever necessary.

Evaluating the source and Quality of River and Groundwater using hydrochemistry and stable isotopesin Tawi Watershed, Jammu District, Jammu and Kashmir, India

Hydrogeochemical and isotopic composition of river and groundwater in Kandi and Sirowal belts of Jammu District in the Union Territory of Jammu and Kashmir was carried out to understand the recharge source and chemical nature of these waters for drinking water quality criteria. Physical parameters (temperature, pH, Total dissolved solids, total hardness and electrical conductivity), major cations and anions (Ca2+, Mg2+, Na+, K+, HCO3-, Cl-, SO42-, NO3-) and stable isotopes (d18O and d2H) inTawi river and groundwater samples from hand pumps and tube wells were measured. The dominant cation is Ca2+ and the dominant anion HCO3- implyingCaHCO3type water in both river and groundwater. To assess the quality of water for drinking purposes, Groundwater Quality Index (GWQI) has been calculated. The GWQI indicates that Kandi and Sirowal belts are showing “Excellent” to “Good” category for drinking purposes. The stable isotopic composition of river water and groundwater is indicative of meteoric origin and enrichment before groundwater recharge. The stable isotopes in water suggest that the active canals in Sirowal belt,and rainfall and river water near the banks in Kandi belt contribute to ground water recharge.

Assessment of Cadmium Toxicity in Drinking Water of Eight Talukas of Upper Sindh

In the present study, 240 groundwater samples were collected from eight Talukas of upper Sindh. The cadmium (Cd) content was determined by atomic absorption spectrophotometer. Concentration (µg/L), Daily Intake ofMetals (DIM),Health Risk Indexes (HRI) for children and adults caused due to Cd were measured through equations of EPA and WHO. Mean concentration of Cd in different Talukas of upper Sindh was found as; Daharki (6.20 µg/L), Ubauro (7.73 µg/L), Kashmore (7.53 µg/L), Tangwani (7.73 µg/L), Garhi Khairo (6.20 µg/L), Thul (5.00 µg/L), Qambar (7.674 µg/L) and Miro Khan (7.47 µg/L). Moreover, percent contamination of each Taluka was found as, Daharki (80%), Ubauro (93%), Kashmore (93%), Tangwani (93%), Gharhi Khairo (70%), Thul (56%), Qambar (93%) and Miro Khan (93%). The DIM of Cd for adult and children was calculated the range for adults was found as; Daharki (0.00006 - 0.00036), Ubauro (0.00006 - 0.00042), Kashmore (0.00006 - 0.00036), Tangwani (0.00006 - 0.00042), Garhi Khairo (0.00003 - 0.00056), Thul (0.00003 - 0.00056), Qambar (0.00008 - 0.00039) and Miro Khan (0.00008 - 0.00039) mg/kg-d, whereas, for children DIM of Cd was found lower than adults. The HRI values show that children compared to adults are under the potential risk threat due to HRI values > 1. Therefore, it can be suggested that groundwater found in above stated areas is unsafe for drinking purposes and must be treated before consumption.

Evaluation of Groundwater Suitability for Irrigation and Drinking Purposes in an Agricultural Region of the North China Plain

Groundwater is an irreplaceable resource for irrigation and drinking in the North China Plain, and the quality of groundwater is of great importance to human health and social development. In this study, using the information from 59 groups of groundwater samples, groundwater quality conditions for irrigation and drinking purposes in an agricultural region of the North China Plain were analyzed. The groundwater belongs to a Quaternary loose rock pore water aquifer. The depths of shallow groundwater wells are 20–150 m below the surface, while the depths of deep groundwater wells are 150–650 m. The sodium adsorption ratio (SAR), sodium percentage (%Na), residual sodium carbonate (RSC), magnesium hazard (MH), permotic index (PI) and electrical conductivity (EC) were selected as indexes to evaluate the shallow groundwater suitability for irrigation. What’s more, the deep groundwater suitability for drinking was assessed and the human health risk of excessive chemicals in groundwater was studied. Results revealed that SAR, Na% and RSC indexes indicated the applicability of shallow groundwater for agricultural irrigation in the study area. We found 57.1% of the shallow groundwater samples were located in high salinity with a low sodium hazard zone. The concentrations of fluorine (F−) in 79.0% of the deep groundwater samples and iodine (I−) in 21.1% of the deep groundwater samples exceeded the permissible limits, respectively. The total hazard quotient (HQ) values of fluorine in over half of the deep groundwater samples exceeded the safety limits, and the health risk degree was ranked from high to low as children, adult females and adult males. In addition to natural factors, the soil layer compression caused by groundwater over-exploitation increased the fluorine concentration in groundwater. Effective measures are needed to reduce the fluorine content of the groundwater of the study area.

Chemical and Pathogen Impacts on Human Health near Aquaculture Areas in West Godavari District of Andhra Pradesh, India

Water is essential for all living organisms in the universe. Chemicals can cause contamination in groundwater near aquacultural activity areas. Keeping in view the hectic aquacultural activity in surrounding locations of Akividu town in West Godavari District of AP, India, it is proposed to assess the chemical and microbial contamination of waters to suggest remedial measures to protect the quality of water for safeguarding the health of the public residing in the nearby habitations who consume these waters for drinking purposes. 16 Groundwater samples were collected and analyzed for assessing the physicochemical parameters viz., pH, Electrical conductivity (EC), Total Dissolved solids (TDS), Total hardness (TH), Total Alkalinity (TA), Na+, K+, Calcium, Magnesium, Chloride, Sulphate, Nitrate and Phosphate, Irrigation parameters like %Na, SAR, KR RSC, and microbial analysis. The study results revealed that the samples were contaminated chemically and also with pathogenic bacteria like Pseudomonas, Citrobacter freundii and Escherichia coli which can cause water-borne diseases. Further, a health survey was carried out to verify the adverse effects to be caused by the chemical and microbial contamination of water on people’s health. The health survey results indicated the sufferings of the people who consume this water for drinking and domestic purposes. The waters are to be treated accordingly to control the chemical and bacterial contamination by using the available treatment methodologies before considering them for drinking purposes.

Analysis of the feasibility of the use of rainwater: A case study for standard school infrastructures

With the growth in water demand worldwide, cities are experiencing increasing difficulties to guarantee the public supply of drinking water. Therefore, the search for alternatives that replace the available sources needs to be disseminated. An alternative to reduce the demand for drinking water is to use the Rainwater harvesting system. This work analyzes the feasibility of implementing a system for capturing, storing, and distributing rainwater for non-drinking purposes in three standard projects of the National Fund for the Development of Education in three locations in the state of Pernambuco: Recife, Caruaru, and Petrolina. To achieve this objective, local rainfall data, the catchment area used and the demand for non-drinking water in the building were analyzed. Then, sizing calculations of the storage reservoir were performed by different methods. The time for return on investment was considered satisfactory for all types located in Recife and for the 1-room type in Caruaru and Petrolina, considering the benefit from the system in the long term. Therefore, the typologies of 6 and 12 rooms in Caruaru and Petrolina were excluded since they had a return time of more than 24 years. The advantages are not only financial, but also environmental, cultural, and educational.