Page 149 - AJWEP-22-6

Water quality of Bharatpur, Nepal

1. Introduction are removed, natural purification of groundwater can
take hundreds of years. Contaminants are typically
21
Water is a fundamental component of life, playing a categorized into chemical, biological, and radioactive
crucial role in the daily functioning of living organisms types. Toxic metals and metalloids present significant
22
and influencing climatic conditions and land formation. health risks to both humans and the environment. High
Groundwater, which resides beneath the Earth’s levels of these substances can lead to severe poisoning,
surface, represents the most abundant source of usable although some are essential as trace micronutrients. For
23
freshwater, constituting approximately 99% of the total example, exposure to hexavalent chromium is linked to
volume. In comparison, surface water in lakes, rivers, a higher risk of cancer. Arsenic is classified as a human
24
and wetlands accounts for 0.87%, while atmospheric carcinogen by both the United States Environmental
moisture constitutes 0.16%. Around one-third of Protection Agency and the International Agency for
1,2
the world’s population depends on groundwater for Research on Cancer. 25,26 Over 200 organic contaminants,
drinking. This resource is especially essential in dry many of which are carcinogenic, have been detected
3
and semi-arid areas, where surface water and rainfall are in groundwater, and this number continues to rise. 27,28
limited. Maintaining a safe and sustainable groundwater These organic substances, derived from carbohydrates,
4
supply is a key to long-term national progress. Clean proteins, fats, and oils, may degrade slowly or not at all,
water is essential for the survival of living organisms posing a persistent threat to groundwater quality. 29,30
and the proper functioning of communities, ecosystems, Contaminated groundwater can adversely impact
and economies. Therefore, it is imperative to regularly human health, environmental quality, and socioeconomic
5
assess the quality of untreated groundwater to minimize development. Excessive levels of fluoride (F ), chloride
−
health risks before consumption. Nevertheless, (Cl ), nitrate (NO ), metals, and organic pollutants are
−
6
−
3
groundwater quality is increasingly threatened by associated with significant health risks. Infants are
31
urbanization, agricultural practices, industrial activities, particularly vulnerable to these contaminants. 15,18,31 In
and climate change. Water contamination primarily addition, the use of untreated groundwater containing
results from increased waste discharge associated with heavy metals and persistent contaminants for irrigation
population growth and various human activities, raising can lead to the accumulation of toxic elements in
significant concerns about maintaining a safe water crops, posing risks to consumers. 32-35 Groundwater
supply. Heavy chemical contaminants frequently contamination also negatively affects soil and forest
7,8
enter groundwater due to untreated industrial and quality, with high groundwater salinity contributing
agricultural discharges in urban areas. The presence to soil salinization in arid agricultural regions.
36
9
of chemical impurities in groundwater can have Furthermore, contamination-induced water shortages
detrimental impacts on public health. Contamination may exacerbate conflicts over water resources and
10
may occur not only at the source but also through the hinder socioeconomic development. 37
formation of chemical by-products during groundwater Groundwater quality research worldwide encounters
movement. Consequently, water must meet specific considerable challenges due to the large number of
11
physical, chemical, and microbiological standards to be water quality parameters, limited data availability, and
considered potable and safe for consumption. 12 the complex nature of groundwater systems. Çiner
Contaminants, such as toxic metals, hydrocarbons, et al. explored the carcinogenic risks associated
38
trace organic compounds, pesticides, microplastics, and with arsenic exposure in South-Central Turkey,
nanoparticles pose significant threats to human health, where levels frequently exceeded guideline limits.
ecosystems, and sustainable development. 13,14 Many of Their study utilized multivariate statistical analysis
these groundwater pollutants originate from naturally to identify trace elements, revealing that geogenic
occurring mineral deposits dissolved in the Earth’s processes played a substantial role in contamination.
crust. 15,16 Groundwater contamination occurs when Yadav et al. assessed groundwater quality in relation
39
harmful substances are introduced into the subsurface to arsenic in the Nawalparasi district, Nepal, using
due to human activities. These contaminants are often multivariate statistical techniques. The study found
colorless and odorless, making their detection and their that nickel (Ni), cadmium (Cd), lead (Pb), chromium
impacts on human health both challenging and chronic. (Cr), and arsenic (As) levels exceeded the World Health
17
Remediation of contaminated groundwater is complex Organization (WHO) permissible limits for drinking
and costly due to its subsurface location and long water, with arsenic concentrations ranging from 60 to
residence times. 18-20 Even after contamination sources 31,000 µg/L during the pre-monsoon and monsoon

Volume 22 Issue 6 (2025) 143 doi: 10.36922/AJWEP025120083