2026-09-25T13:25:40Zhttps://univendspace.univen.ac.za/server/oai/requestoai:univendspace.univen.ac.za:11602/18302024-09-10T14:39:05Zcom_11602_1930com_11602_1915com_11602_1897com_11602_737col_11602_2152col_11602_738
Edokpayi, J. N.
Enitan, A. M.
Mutileni, N
2021
2021-12-13T06:58:08Z
2021-12-13T06:58:08Z
2021-11
Mutileni, N. (2021) Assessment of health risk association with groundwater from Collins Chabane and Makhado Municipality of Vhembe District. University of Venda, South Africa.<http://hdl.handle.net/11602/1830>.
http://hdl.handle.net/11602/1830
Mutileni N. Assessment of health risk association with groundwater from Collins Chabane and Makhado Municipality of Vhembe District. []. , 2021 [cited yyyy month dd]. Available from: http://hdl.handle.net/11602/1830
Mutileni, N. (2021). <i>Assessment of health risk association with groundwater from Collins Chabane and Makhado Municipality of Vhembe District</i>. (). . Retrieved from http://hdl.handle.net/11602/1830
Mutileni, N. <i>"Assessment of health risk association with groundwater from Collins Chabane and Makhado Municipality of Vhembe District."</i> ., , 2021. http://hdl.handle.net/11602/1830
TY - Dissertation
AU - Mutileni, N
AB - Water is essential to life, but many people lack access to clean and safe drinking water, and many
die of preventable waterborne diseases. The study conducted assessed groundwater vulnerability to
Physico-chemical and microbial contamination across the Collins Chabane and Makhado
Municipality. A three-set of samples (for metals, non-metals and microbial analysis) were randomly
collected from twenty (20) primary schools, fifteen (15) private boreholes, and three (3) communal
boreholes of Vhembe district, Limpopo province, South Africa. The physicochemical water quality
parameters (pH, EC, and TDS) were measured using the YSI Professional Plus meter . At the same
time, turbidity and salinity were measured using an Orbeco-Hellige portable turbidimeter and
Extech multimeter, respectively. The physicochemical parameters measure in the field comply with
the recommended standard set by South African Nation Standard SANS (2015) apart from the pH
value detected in one sample collected in the wet season. Nitrate concentration (2.03–1532 mg/L)
was obtained in high values in the most sample in the wet season. Some boreholes can have a
noticeable taste due to chloride concentration (14.12–690 mg/L).
The following metals Cd, Pb, Hg, As, Al, Mn, Fe, Co, Ni, Cu, Cr and Zn, Ca, K, Mg, and Na were
analysed using an Inductively coupled plasma Mass spectrometer. The analytical results for major
cations i.e., Ca, Mg, K and Na range between 14.20 – 349 mg/L, 11.40 – 309 mg/L, 0.49–12.80
mg/L, and 13.60 – 97.80 mg/L, respectively. The high concentration of Ca and Mg recorded in
some of the sites exceeded the recommended limit set by DWAF (1996) and WHO (2015). The
analytical results of heavy metal indicated that Ni (16.35 – 308.53 μg/L), Cr (27.46 – 72.84 μg/L),
and Al (0.14 – 0.76 mg/L) were above the standard limits of SANS 241 (2015) in some of the sites.
The membrane filtration method was employed to determine faecal indicator organisms. The results
obtained for E. coli ranged between 0.0 – 76 cfu/100 ml in the dry season, while numerous values
were detected for total coliform in both dry and wet season. All borehole failed to comply with
SANS 241 and WHO standard limit in terms of total coliform while, 42.11% of borehole failed to
comply with SANS 241 in terms of E. coli.
Groundwater geochemistry was evaluated through Gibb’s diagram and Piper plot. The most
dominant water type across all groundwater sample was Mg-HCO3 (40.79%, n=76) and Mg-Cl
water type (38.16%, n=76) throughout the study period. Twenty one parameters (pH, EC, Cl-, NO3-
, F-, SO4-2, HCO3-, Ca, Mg, K Na, Total Hardness as CaCO3, Cr, Mn, Co, Ni, Cu, Zn, Hg, Pb and
Fe) were taken into consideration for the computation of water quality index (WQI). The WQI
values of the selected school, household, and communal samples (50-103 and 25-101, 26-485 and
21-442, and 35-57 and 50-56, respectively) fell between the excellent to poor, excellent to
unsuitable and excellent to good water based on the physico-chemical parameters used during dry
and wet season, respectively. Some household samples had poor (21.43%), and unsuitable water
(10.71%) during the assessment period. Nitrate was the principal element with enormously high
concentrations that violated the WHO and SANS 241 permissible limit for drinking purpose which
caused high levels of WQI. The source of contamination could be anthropogenic activities.
Human health risk associated with the water quality parameters assessed was calculated using noncarcinogenic
effects using hazard quotient toxicity potential (HQing), cumulative hazard index (HI)
and daily human exposure dose (Ding) of drinking water through ingestion pathway. The computed
non-carcinogenic effects (HQing) and HI for children and adult were ≥1 throughout the assessment.
The main contributors to non-carcinogenic health risks in this investigation were Cr, Hg, and As.
The carcinogenic risk assessment evaluated from selected heavy metals (Cr, Cd, Hg, Pb and As)
exceeded the suggested potential risk limits apart from As and Hg for Adult in Dry season. Cr and
Pb were above the carcinogenic indices of 1E-04 and 1E-06 throughout the season. Hence, these
parameters can pose potential risk to both age group. Therefore, preventive measure should be
implemented to prevent long term cumulative exposure risk. Quantitative microbial risk assessment
(QMRA) was carried out to determine the risks of infection and illness due to consumption of
groundwater. The estimation of QMRA indices values suggest that school boreholes had higher
risk of infection than household and communal sites. Highest risk of infection has been detected
during the month of November (wet season) in 2019. Only 30% school boreholes had an extremely
high annual risk (90.52-100% probability) of E. coli infections to children. High probability values
(90.5-100% probability) for annual risk of infection in all age group has been observed in 35.90%
school samples throughout the assessment. Only 10.26% of school samples had annual risk of
illness probability value of 35% in all age group. The annual risk of E. coli infections and illness
was high in household site with 100% and 35% for all age group respectively. Meanwhile, 80.94
and 28.33% were the highest maximum values assessed for infection and illness in communal site.
The estimation of QMRA indices suggest groundwater from the investigated study being a hazard.
The methods of analysis in this study, suggested possible contamination of groundwater by
anthropogenic activities such as small-scale agricultural activities, faecal contamination (pit latrines
and septic storage), domestic waste on land, waste from concentrated livestock and natural
processes such as microbial interference, weathering and dissolution. Preventive and mitigation
measures to minimise such risks are indispensable.
DA - 2021-11
DB - ResearchSpace
DP - Univen
KW - Water Quality Index
KW - Health Risk Assessment
KW - Hydrogeochemistry
KW - Correlation
KW - Quantitative Microbial Risk Assessment
LK - https://univendspace.univen.ac.za
PY - 2021
T1 - Assessment of health risk association with groundwater from Collins Chabane and Makhado Municipality of Vhembe District
TI - Assessment of health risk association with groundwater from Collins Chabane and Makhado Municipality of Vhembe District
UR - http://hdl.handle.net/11602/1830
ER -
MESHWR
Department of Hydrology and Water Resources
Water is essential to life, but many people lack access to clean and safe drinking water, and many
die of preventable waterborne diseases. The study conducted assessed groundwater vulnerability to
Physico-chemical and microbial contamination across the Collins Chabane and Makhado
Municipality. A three-set of samples (for metals, non-metals and microbial analysis) were randomly
collected from twenty (20) primary schools, fifteen (15) private boreholes, and three (3) communal
boreholes of Vhembe district, Limpopo province, South Africa. The physicochemical water quality
parameters (pH, EC, and TDS) were measured using the YSI Professional Plus meter . At the same
time, turbidity and salinity were measured using an Orbeco-Hellige portable turbidimeter and
Extech multimeter, respectively. The physicochemical parameters measure in the field comply with
the recommended standard set by South African Nation Standard SANS (2015) apart from the pH
value detected in one sample collected in the wet season. Nitrate concentration (2.03–1532 mg/L)
was obtained in high values in the most sample in the wet season. Some boreholes can have a
noticeable taste due to chloride concentration (14.12–690 mg/L).
The following metals Cd, Pb, Hg, As, Al, Mn, Fe, Co, Ni, Cu, Cr and Zn, Ca, K, Mg, and Na were
analysed using an Inductively coupled plasma Mass spectrometer. The analytical results for major
cations i.e., Ca, Mg, K and Na range between 14.20 – 349 mg/L, 11.40 – 309 mg/L, 0.49–12.80
mg/L, and 13.60 – 97.80 mg/L, respectively. The high concentration of Ca and Mg recorded in
some of the sites exceeded the recommended limit set by DWAF (1996) and WHO (2015). The
analytical results of heavy metal indicated that Ni (16.35 – 308.53 μg/L), Cr (27.46 – 72.84 μg/L),
and Al (0.14 – 0.76 mg/L) were above the standard limits of SANS 241 (2015) in some of the sites.
The membrane filtration method was employed to determine faecal indicator organisms. The results
obtained for E. coli ranged between 0.0 – 76 cfu/100 ml in the dry season, while numerous values
were detected for total coliform in both dry and wet season. All borehole failed to comply with
SANS 241 and WHO standard limit in terms of total coliform while, 42.11% of borehole failed to
comply with SANS 241 in terms of E. coli.
Groundwater geochemistry was evaluated through Gibb’s diagram and Piper plot. The most
dominant water type across all groundwater sample was Mg-HCO3 (40.79%, n=76) and Mg-Cl
water type (38.16%, n=76) throughout the study period. Twenty one parameters (pH, EC, Cl-, NO3-
, F-, SO4-2, HCO3-, Ca, Mg, K Na, Total Hardness as CaCO3, Cr, Mn, Co, Ni, Cu, Zn, Hg, Pb and
Fe) were taken into consideration for the computation of water quality index (WQI). The WQI
values of the selected school, household, and communal samples (50-103 and 25-101, 26-485 and
21-442, and 35-57 and 50-56, respectively) fell between the excellent to poor, excellent to
unsuitable and excellent to good water based on the physico-chemical parameters used during dry
and wet season, respectively. Some household samples had poor (21.43%), and unsuitable water
(10.71%) during the assessment period. Nitrate was the principal element with enormously high
concentrations that violated the WHO and SANS 241 permissible limit for drinking purpose which
caused high levels of WQI. The source of contamination could be anthropogenic activities.
Human health risk associated with the water quality parameters assessed was calculated using noncarcinogenic
effects using hazard quotient toxicity potential (HQing), cumulative hazard index (HI)
and daily human exposure dose (Ding) of drinking water through ingestion pathway. The computed
non-carcinogenic effects (HQing) and HI for children and adult were ≥1 throughout the assessment.
The main contributors to non-carcinogenic health risks in this investigation were Cr, Hg, and As.
The carcinogenic risk assessment evaluated from selected heavy metals (Cr, Cd, Hg, Pb and As)
exceeded the suggested potential risk limits apart from As and Hg for Adult in Dry season. Cr and
Pb were above the carcinogenic indices of 1E-04 and 1E-06 throughout the season. Hence, these
parameters can pose potential risk to both age group. Therefore, preventive measure should be
implemented to prevent long term cumulative exposure risk. Quantitative microbial risk assessment
(QMRA) was carried out to determine the risks of infection and illness due to consumption of
groundwater. The estimation of QMRA indices values suggest that school boreholes had higher
risk of infection than household and communal sites. Highest risk of infection has been detected
during the month of November (wet season) in 2019. Only 30% school boreholes had an extremely
high annual risk (90.52-100% probability) of E. coli infections to children. High probability values
(90.5-100% probability) for annual risk of infection in all age group has been observed in 35.90%
school samples throughout the assessment. Only 10.26% of school samples had annual risk of
illness probability value of 35% in all age group. The annual risk of E. coli infections and illness
was high in household site with 100% and 35% for all age group respectively. Meanwhile, 80.94
and 28.33% were the highest maximum values assessed for infection and illness in communal site.
The estimation of QMRA indices suggest groundwater from the investigated study being a hazard.
The methods of analysis in this study, suggested possible contamination of groundwater by
anthropogenic activities such as small-scale agricultural activities, faecal contamination (pit latrines
and septic storage), domestic waste on land, waste from concentrated livestock and natural
processes such as microbial interference, weathering and dissolution. Preventive and mitigation
measures to minimise such risks are indispensable.
NRF
1 online resource (xiv, 156 leaves) : color illustrations, color maps
en
University of Venda
Water Quality Index
UCTD
Health Risk Assessment
Hydrogeochemistry
Correlation
Quantitative Microbial Risk Assessment
551.490968257
Groundwater -- South Africa -- Limpopo
Water -- South Africa -- Limpopo
Hydrogeology -- South Africa -- Limpopo
Groundwater Health aspects -- South Africa -- Limpopo
Groundwater -- Pollution -- South Africa -- Limpopo
Groundwater -- Quality
Assessment of health risk association with groundwater from Collins Chabane and Makhado Municipality of Vhembe District
Dissertation
open.access