Seasonal Variation of Drinking Water Quality and Human Health Risk Assessment: A Case Study in Rural Village of the Eastern Cape, South Africa
Abstract
:1. Introduction
2. Materials and Methods
2.1. Reagents
2.2. Sampling Site Description
2.3. Sample Collection and Analysis
2.4. Instrumentation
2.5. Total Water Hardness
2.6. Water Quality Assessment
2.7. Health Risk Assessment
3. Results and Discussion
3.1. Physicochemical Parameters
3.2. Major Elements
3.3. Total Hardness
3.4. Potential Harmful Trace Elements
3.5. Water Quality Assessment
3.6. Health Risk Assessment
3.6.1. Chronic Daily Intakes (CDI) of Trace Metals
3.6.2. Hazard Quotient (HQ)
3.6.3. Carcinogenic Risk
4. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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ICP-OES Conditions | ||
---|---|---|
RF generator power | W | 1150 |
RF generator frequency | MHz | 40 |
Coolant gas flowrate | L min−1 | 12 |
Carrier gas flow rate | L min−1 | 0.7 |
Auxiliary gas | L min−1 | 1.0 |
Max integration times | s | 15 |
Pump rate | rpm | 50 |
Viewing configuration | Axial (trace metals), Radial (major metals) | |
Replicate | 3 | |
Flush time | s | 30 |
Total Hardness | Classification of Hardness | ||
---|---|---|---|
mg/L | |||
WHO | Rand Water | WHO | Rand Water |
<17 | 0–50 | Soft | Soft |
17–60 | 50–100 | Slightly hard | Moderately soft |
60–120 | 100–150 | Moderately hard | Slightly hard |
120–180 | 150–200 | Hard | Moderately hard |
>180 | 200–300 | Very hard | Hard |
- | >300 | - | Very hard |
WQI Values | Classification |
---|---|
<50 | Excellent water |
50–100 | Good water |
100–200 | Poor water |
200–300 | Very poor water |
>300 | Unsuitable for drinking |
Parameters | SANS 241 Limits (2015), (Si) | Concentration (Ci) | Assigned Weight (AWi) | Relative Weight (RWi) | ||
---|---|---|---|---|---|---|
Tap Water-Dry Season | Windmill-Dry Season | Tap Water Wet Season | ||||
pH | 8.5 | 7.24 ± 0.05 | 7.18 ± 0.04 | 7.26 ± 0.05 | 4 | 0.080 |
Conductivity (µS/cm) | 1700 | 550 ± 20 | 550 ± 15 | 550 ± 25 | 3 | 0.060 |
TDS (mg/L) | 1200 | 232 ± 12 | 233 ± 13 | 230 ± 14 | 3 | 0.060 |
Potassium (mg/L) | 50 | 3.96 ± 0.09 | 4.45 ± 0.03 | 4.74 ± 0.12 | 2 | 0.040 |
Sodium ion (mg/L) | 200 | 40.6 ± 0.9 | 48.7 ± 0.6 | 40.7 ± 0.5 | 2 | 0.040 |
Calcium ion (mg/L) | 150 | 87.9 ± 1.1 | 89.0 ± 2.1 | 80.4 ± 1.5 | 2 | 0.040 |
Magnesium ion (mg/L) | 70 | 54.2 ± 1.2 | 46.9 ± 2.3 | 56.3 ± 1.7 | 2 | 0.040 |
Aluminium (mg/L) | 0.3 | 3.36 ± 0.04 | 2.19 ± 0.05 | 2.38 ± 0.03 | 4 | 0.080 |
Total hardness as CaCO3 (mg/L) | 180 * | 442 ± 15 | 415 ± 10 | 432 ± 15 | 5 | 0.10 |
Zinc (µg/L) | 5000 | 760 ± 3 | 570 ± 13 | 150 ± 7 | 1 | 0.020 |
Copper (µg/L) | 200 | 49.0 ± 0.7 | ND | 120 ± 6 | 2 | 0.040 |
Cobalt (µg/L) | 500 | 20.0 ± 0.2 | 15.0 ± 0.8 | 26.0 ± 0.7 | 5 | 0.10 |
Vanadium (µg/L) | 200 | 160 ± 3 | 390 ± 15 | 550 ± 12 | 5 | 0.10 |
Manganese (µg/L) | 400 | 390 ± 6 | 710 ± 10 | 1580 ± 20 | 5 | 0.10 |
Chromium (µg/L) | 50 | ND | 260 ± 8 | 250 ± 11 | 5 | 0.10 |
Elements | Tap Water-Dry Season | Windmill-Dry Season | Tap Water-Wet Season | RFD | ||||||
---|---|---|---|---|---|---|---|---|---|---|
Men | Women | Children | Men | Women | Children | Men | Women | Children | ||
As | 8.72 | 9.44 | 9.443 | 5.24 | 5.67 | 5.67 | 16.3 | 17.7 | 17.7 | 0.3 |
Cd | 0.27 | 0.29 | 0.293 | 0.21 | 0.23 | 0.23 | 0.41 | 0.45 | 0.45 | 0.5 |
Co | 0.61 | 0.66 | 0.663 | 0.47 | 0.51 | 0.51 | 0.79 | 0.85 | 0.85 | 20 |
Cr | 0 | 0 | 0.000 | 8.00 | 8.67 | 8.67 | 7.63 | 8.27 | 8.27 | 3 |
Cu | 1.51 | 1.64 | 1.637 | 0 | 0 | 0 | 3.62 | 3.93 | 3.93 | 40 |
Mn | 11.9 | 12.9 | 12.9 | 21.9 | 23.8 | 23.8 | 48.7 | 52.7 | 52.7 | 140 |
Pb | 2.11 | 2.29 | 2.29 | 1.98 | 2.14 | 2.14 | 2.47 | 2.67 | 2.67 | 3.6 |
Sb | 4.28 | 4.64 | 4.64 | 1.82 | 1.98 | 1.98 | 1.53 | 1.65 | 1.65 | 0.4 |
Se | 4.55 | 4.93 | 4.93 | 2.30 | 2.49 | 2.49 | 2.60 | 2.82 | 2.82 | 5 |
Tl | 26.9 | 29.1 | 29.1 | 19.2 | 20.8 | 20.8 | 19.6 | 21.3 | 21.3 | 0.08 |
V | 5.00 | 5.41 | 5.41 | 12.1 | 13.2 | 13.2 | 17.1 | 18.5 | 18.5 | 7 |
Zn | 23.5 | 25.5 | 25.5 | 17.5 | 18.9 | 18.9 | 4.70 | 5.09 | 5.09 | 300 |
Elements | Tap Water-Dry Season | Windmill-Dry Season | Tap Water Wet Season | ||||||
---|---|---|---|---|---|---|---|---|---|
Men | Women | Children | Men | Women | Children | Men | Women | Children | |
As | 29.1 | 31.5 | 31.5 | 17.5 | 18.9 | 18.9 | 54.4 | 59.0 | 59.0 |
Cd | 0.54 | 0.59 | 0.59 | 0.42 | 0.45 | 0.45 | 0.82 | 0.89 | 0.89 |
Co | 0.03 | 0.03 | 0.03 | 0.02 | 0.03 | 0.03 | 0.04 | 0.04 | 0.04 |
Cr | 0.00 | 0.00 | 0.00 | 2.67 | 2.89 | 2.89 | 2.54 | 2.76 | 2.76 |
Cu | 0.038 | 0.041 | 0.041 | 0.000 | 0.000 | 0.000 | 0.091 | 0.098 | 0.098 |
Mn | 0.085 | 0.092 | 0.092 | 0.16 | 0.17 | 0.17 | 0.35 | 0.38 | 0.38 |
Pb | 0.59 | 0.64 | 0.64 | 0.55 | 0.59 | 0.59 | 0.69 | 0.74 | 0.74 |
Sb | 10.7 | 11.6 | 11.6 | 4.56 | 4.94 | 4.94 | 3.82 | 4.13 | 4.13 |
Se | 0.91 | 0.99 | 0.99 | 0.46 | 0.50 | 0.50 | 0.52 | 0.56 | 0.56 |
Tl | 336 | 364 | 364 | 240 | 260 | 260 | 245 | 266 | 266 |
V | 0.71 | 0.77 | 0.77 | 1.73 | 1.88 | 1.88 | 2.44 | 2.64 | 2.64 |
Zn | 0.078 | 0.085 | 0.085 | 0.058 | 0.063 | 0.063 | 0.016 | 0.017 | 0.017 |
Elements | Tap Water-Dry Season | Windmill-Dry Season | Tap Water Wet Season | ||||||
---|---|---|---|---|---|---|---|---|---|
Men | Women | Children | Men | Women | Children | Men | Women | Children | |
As | 4.01 × 10−2 | 4.34 × 10−2 | 4.34 × 10−2 | 2.41 × 10−2 | 2.61 × 10−2 | 2.61 × 10−2 | 7.49 × 10−2 | 8.14 × 10−2 | 8.14 × 10−2 |
Cd | 1.02 × 10−1 | 1.10 × 10−1 | 1.11 × 10−1 | 7.98 × 10−2 | 8.74 × 10−2 | 8.74 × 10−2 | 1.56 × 10−1 | 1.71 × 10−1 | 1.71 × 10−1 |
Pb | 1.79 × 10−2 | 1.94 × 10−2 | 1.94 × 10−2 | 1.68 × 10−2 | 1.82 × 10−2 | 1.82 × 10−2 | 2.09 × 10−2 | 2.27 × 10−2 | 2.27 × 10−2 |
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Mandindi, W.Z.; Nyaba, L.; Mketo, N.; Nomngongo, P.N. Seasonal Variation of Drinking Water Quality and Human Health Risk Assessment: A Case Study in Rural Village of the Eastern Cape, South Africa. Water 2022, 14, 2013. https://doi.org/10.3390/w14132013
Mandindi WZ, Nyaba L, Mketo N, Nomngongo PN. Seasonal Variation of Drinking Water Quality and Human Health Risk Assessment: A Case Study in Rural Village of the Eastern Cape, South Africa. Water. 2022; 14(13):2013. https://doi.org/10.3390/w14132013
Chicago/Turabian StyleMandindi, Wendy Zimkhitha, Luthando Nyaba, Nomvano Mketo, and Philiswa Nosizo Nomngongo. 2022. "Seasonal Variation of Drinking Water Quality and Human Health Risk Assessment: A Case Study in Rural Village of the Eastern Cape, South Africa" Water 14, no. 13: 2013. https://doi.org/10.3390/w14132013
APA StyleMandindi, W. Z., Nyaba, L., Mketo, N., & Nomngongo, P. N. (2022). Seasonal Variation of Drinking Water Quality and Human Health Risk Assessment: A Case Study in Rural Village of the Eastern Cape, South Africa. Water, 14(13), 2013. https://doi.org/10.3390/w14132013