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Water quality impact from mining in Prek Te

Figure 1. Map of surface water sampling locations

of Prek Te and the Mekong River. Surface water samples sensitivity, and guarantees consistency in the detection
were collected at a depth of approximately 0 – 30 cm. of heavy metals and trace elements in water samples.
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Sterilized polytetrafluoroethylene bottles were used to The concentrations of As, Cr, Ni, Cu, Zn, Cd, and Pb
store 100 mL of each water sample. To preserve the were determined using an inductively coupled plasma
samples, nitric acid (HNO ) was added, and they were mass spectrometry (ICP-MS; 8990 GC System, Agilent,
3
stored in an ice box during field sampling. Subsequently, United States). Calibration standards of 1 µg/L, 5 µg/L,
the samples were transferred to a refrigerator set at 4°C 10 µg/L, 20 µg/L, 50 µg/L, and 100 µg/L were prepared
for storage until analysis for As, chromium (Cr), Ni, Cu, from a stock multielement standard solution for ICP
Zn, Cd, and Pb. 16 (Sigma-Aldrich, Switzerland) in 2% HNO .
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Physicochemical parameters were measured on-site For quality control, a certified reference material
at each sampling location. pH was measured using a (CRM), River Thames water (LGC6019, LGC
HANNA pH/ORP meter HI98191 (HANNA, Italy), Standards, United Kingdom), was used to ensure
while electrical conductivity (EC) and total dissolved accuracy and precision in the measurements. After every
solids (TDS) were determined using a HANNA 10 sample analyses, the CRM sample was run to verify
Conductivity/TDS/Salinity meter HI 98192 (HANNA, the ICP-MS accuracy. If the recovery rate fell outside
Italy). In addition, dissolved oxygen (DO) was measured the recommended range (80 – 120%), a new calibration
with a HANNA HI 9147 meter (HANNA, Italy). curve was applied before further analysis.

2.3. Samples preparation and analysis 2.4. Health risk assessment
Prior to instrumental analysis, filtration was carried out Health risk assessment is a systematic process used to
to evaluate the dissolved fraction of the water samples. evaluate the potential adverse health effects resulting
Sartorius filter papers (0.45 µm pore size) were used for from exposure to environmental hazards. It is a widely
filtration, and 50 mL of filtered water was extracted for adopted tool used by regulatory agencies, health
analysis. organizations, and industries to ensure that activities
Filtering water samples is a standard procedure such as mining, manufacturing, and waste disposal do
that enhances precision, sensitivity, and reliability not pose significant health risks to human populations.
in analytical measurements. It minimizes instrument In this study, water samples from residential areas along
blockages, reduces contamination, improves analytical Prek Te were analyzed to assess lifetime cancer risk

Volume 22 Issue 2 (2025) 89 doi: 10.36922/AJWEP025060037