Risk of Chemical Pollution in Olifants River Basin, South Africa: Human Health Implications

Abstract

Chemical pollution in freshwater ecosystems poses a significant environmental threat, often hindering access to safe drinking water for human populations. The Olifants River Basin in South Africa is particularly vulnerable due to escalating mining and agricultural activities, and domestic waste discharged into the rivers. In this study, the risk posed to humans by exposure to potentially toxic elements (PTEs) in water from two rivers, the Blyde and Steelpoort, was assessed. Water samples were collected from upstream, midstream, and downstream locations of these rivers, and the concentrations of eight PTEs (Arsenic, Cadmium, Chromium, Iron, Manganese, Nickel, Lead, and Zinc) were determined using inductively coupled plasma-optical emission spectrophotometry. Furthermore, two pathways of exposure, direct ingestion and dermal absorption, were used to evaluate their potential impacts on human health. The findings indicate that direct ingestion poses a greater risk to human health compared to dermal absorption. While PTEs may pose little non-carcinogenic risk for adults, higher risk was observed in children. This is an indication that children are at higher risk using water from the rivers, sometimes without any form of treatment. When carcinogenic risks (CRs) were computed for both adults and children for As, Cr, Ni, and Pb levels, the CR values were above the threshold limit, except for Pb, indicating a potential carcinogenic risk. This study underscores the need for regular monitoring of chemical pollution, and the implementation of effective mitigation strategies to safeguard both river ecosystems and human health, including proper treatment of water for domestic and agricultural purposes.

1. Introduction

Many freshwater ecosystems are being polluted mainly due to rapid population growth leading to an increase in agricultural, industrial and domestic activities, and a lack of sufficient environmental policies and implementation. Among freshwater ecosystems, rivers are undoubtedly among the most polluted ecosystems due to anthropogenic activities [1,2]. The discharge from these human activities contains among other pollutants that are potentially toxic (PTEs), some of which can have hazardous effects on the environment [3,4]. Some of these elements are of environmental concern due to their persistence and toxicity, which pose a significant threat to both the aquatic environment and human life [5,6]. These elements may be accumulated in the water and sediment and in the aquatic biota. Usually, suspended sediments adsorb pollutants from the water, thus lowering their concentration in the water column.

Chemical pollution is more severe in developing countries because of inadequate municipal waste management systems, which fail to prevent the indiscriminate discharge of waste into rivers and lakes [7,8]. Although many developing countries have made significant progress in improving water quality for their citizens over the past few decades, there is still a considerable portion of the population lacking access to good drinking water. Consequently, they are susceptible to various waterborne diseases [9].

Many studies have documented elevated concentrations of PTEs in surface water sources, contributing to a range of health complications [10,11,12,13]. Thus, depending on the chemical element and its chemical form in water, prolonged exposure can affect target tissues such as brain, liver, bones, and kidneys in the human body resulting in serious health problems [14]. Recognizing the hazards posed by certain elements, the World Health Organization (WHO) has established limit values for elements in drinking water [15]. Therefore, health risk assessment is important in determining the possible health effects of water bodies that are contaminated.

South Africa is facing water crises, mainly linked to water quality rather than quantity. Many rivers are polluted, primarily due to discharge from activities such as mining, agriculture, industry, and domestic sources. In recent years, the Olifants River Basin has experienced rapid human settlement, driven by increasing economic activities like mining and agriculture. These activities, coupled with population growth, place significant pressure on the basin’s water resources. Previous studies on water quality in the basin have demonstrated that certain elements can pose health risks to humans who rely on the rivers for drinking water, food (e.g., fish), and recreation. In rural areas with limited access to potable water, local communities often have no choice but to use surface water to meet their basic needs [16]. Unfortunately, various anthropogenic activities, including mining, agriculture and industry, are polluting these water resources.

The Blyde and Steelpoort rivers have been underrepresented in the existing literature, despite an increase in human activities in their catchments over the last decade. A primary concern in the study area is that many communities depend exclusively on surface water for domestic, recreational, and religious purposes. The spatial variation in eight PTEs (As, Cd, Cr, Fe, Mn, Ni, Pb, and Zn) in the surface water of the Blyde and Steelpoort rivers within the Olifants River Basin had already been assessed [17]. Currently, there are no data available on the trends of human health risk assessments related to element contamination in most rivers of the area. This study aims to significantly contribute to understanding the health risks faced by communities living in these catchments. Thus, investigating the impact of PTEs and assessing human health risks in these rivers is crucial. The objective of this study was to evaluate the risks associated with both oral and dermal exposures to PTE concentrations in the rivers. This health risk assessment is significant because it represents the first evaluation of these exposure routes in these vital water resources. The findings may offer practical insights or recommendations for policymakers, potentially leading to improved regulations or public health interventions based on the specific risks identified.

2. Materials and Methods

2.1. Study Area

The Blyde river sub-catchment spans approximately 2000 km² and is impacted by various sources of anthropogenic pollution. These include domestic waste in the upstream section, agricultural activities in the midstream, and residential and game reserves in the downstream area. In contrast, the Steelpoort river catchment covers about 7139 km². Within this catchment, agricultural practices and human settlements are prevalent in the upstream and downstream, respectively, while the midstream is affected mainly by mining and smelting operations. Consequently, the water quality of both rivers is increasingly threatened by contamination stemming from mining, and industrial and agricultural sources [18].

2.2. Data Collection

The data for this study were taken from [17]. Water samples were collected during low flow (winter and spring) and high flow (summer and autumn) at upstream, midstream, and downstream locations of the Blyde river (B1, B2 and B3) and Steelpoort river (S1, S2 and S3) (Figure 1). At each site, samples were taken at the two littoral zone edges and main channel center of the river to form a composite sample. The samples were collected in 100 mL acid pre-treated polyethylene bottles and stored in a refrigerator (4 °C) prior to analysis.

The concentrations of As, Cd, Cr, Fe, Mn, Ni, Pb, and Zn were determined using an inductively coupled plasma–optical emission spectrophotometer (ICP-OES; Perkin Elmer, Optima 2100 DV, Waltham, MA, USA). Analytical accuracy was determined using certified standards (De Bruyn Spectroscopic Solutions 500 MUL20-50 STD2, Midrand, South Africa), and recoveries were within 10% of the certified reference material. Cd and Cu were below the detection level at all sampling sites, and therefore were not included in further analysis. The mean concentrations of the PTEs were determined for each river. The limits of detection of As, Cd, Cr, Cu, Ni, Pb, and Zn were on the level of <0.001, and the limits of Fe and Mn were on the level of <0.025.

2.3. Quantitative Health Risk Assessment

A human health risk assessment was conducted to determine the potential adverse health effects in individuals who may be exposed to PTE by drinking water from the rivers [19]. This assessment involves estimating the risk level associated with each chemical contaminant in the water. Common pathways of exposure for individuals include direct ingestion and dermal absorption through skin contact [20]. The exposure dose for determining human health risk was calculated using the equations below:

$$CDI\left(ingestion\right)=Cw\times IR\times EF\times ED/BW\times AT$$

(1)

$$CDI\left(dermal\right)=Cw\times SA\times Kp\times ET\times IR\times EF\times ED\times CF/BW\times AT$$

(2)

where CDI_ingestion is the average chronic daily intake from direct ingestion of water (mg/kg/day); CDI_dermal is the chronic daily intake through dermal absorption (mg/kg/day); Cw is the average concentration of the estimated chemicals in water (mg/L); and Kp is the dermal permeability coefficient in water (cm/h): 0.001 for As, Fe, and Mn, 0.002 for Cr, 0.004 for Ni and Pb, and 0.006 for Zn [21]. The remaining constants in the above equations are listed in

Table 1. Health risk assessment of different exposures through parameters.

Parameter	Unit	Child	Adult
Exposure Frequency (EF)	Day/year	365	365
Body Weight (BW)	kg	15	70
Ingestion Rate (IR) or Daily Intake (DI)	L/day	1.8	2.2
Exposure Duration (ED)	Years	6	70
Skin Surface Area (SA)	cm3	6600	18,000
Exposure Time (ET)	Hours/day	1	0.58
Conversion Factor (CF)	L/cm3	0.001	0.001
Averaging Time (AT) Particular Emission Factor (PEM)	Days Days m3/kg	365 × 6 1.3 × 109	365 × 70 1.3 × 103

Adapted from [22].

.

The potential non-carcinogenic risks due to chemical exposure were assessed by comparing the calculated contaminant exposures from ingestion and dermal routes with their respective reference doses (RfDs). The RfD values for ingestion and dermal exposure to As, Cr, Fe, Mn, Ni, Pb, and Zn are shown in

Table 2. Oral and dermal reference doses (RfDs) for potentially toxic elements.

Element	RfD (mg/kg/Day)	Reference
Oral reference dose
As	0.0003	[23,24]
Cr	0.003	[23,25]
Fe	0.7	[26]
Mn	0.14	[23,27]
Ni	0.02	[23,26]
Pb	0.0014	[25,27]
Zn	0.3	[23,28]
Dermal reference dose
As	0.000123	[29]
Cr	0.000015	[30]
Fe	0.045	[29]
Mn	0.00096	[25,28]
Ni	0.0008	[25]
Pb	0.00042	[25]
Zn	0.06	[29]

.

The hazard quotient (HQ), which evaluates the potential toxicity of an individual’s average daily intake relative to the reference dose through ingestion and dermal exposure, can be calculated using the following equation:

HQ_{ingestion/dermal} = CDI_{ingestion/dermal}/RfD_{ingestion/dermal}

(3)

An HQ < 1 is assumed to be safe and taken as significantly non-carcinogenic, but HQ > 1 indicates a risk to those exposed to the contaminants [31].

To evaluate the overall potential non-carcinogenic effects of multiple metals and exposure pathways, the sum of the computed HQs for each metal was expressed as the hazard index (HI) [22]. An HI > 1 indicates that exposure may pose a potential adverse effect on human health [25].

Carcinogenic risk (CR) through ingestion pathway was estimated using the equation below [22,30,32]:

CR_ingestion = CDI_ingestion × CSF

(4)

where CR_ingestion is cancer risk through the ingestion of PTEs in water and CSF is, the cancer slope factor (mg/kg/day). The cancer slope factors (CSFs) for ingestion are 1.5, 0.5, 0.0085, and 1.7 for As, Cr, Pb, and Ni, respectively. The CSFs for dermal risk are available for only As and Cr, and the values are 3.66 and 20, respectively [21].

3. Results and Discussion

3.1. Potentially Toxic Elements

The mean, minimum, and maximum concentrations of the PTEs in the upstream, midstream, and downstream of the two rivers are shown in

Table 3. Mean PTE concentrations (mg/L) of the water in the Blyde river and Steelpoort river.

	Upstream			Midstream			Downstream
	Mean	Min	Max	Mean	Min	Max	Mean	Min	Max
Blyde River
As	0.004	0.003	0.005	0.007	0.007	0.008	0.01	0.009	0.01
Cr	0.003	0.001	0.004	0.005	0.005	0.006	0.009	0.007	0.011
Fe	0.07	0.04	0.1	0.02	0.007	0.03	0.03	0.023	0.04
Mn	0.01	0.01	0.01	0.05	0.05	0.06	0.08	0.08	0.09
Ni	0.06	0.05	0.06	0.12	0.09	0.14	0.05	0.05	0.05
Pb	0.001	0.001	0.001	0.001	0.001	0.001	0.002	0.001	0.003
Zn	0.008	0.007	0.01	0.017	0.013	0.02	0.004	0.004	0.004
Steelpoort River
As	0.006	0.005	0.007	0.003	0.002	0.004	0.003	0.002	0.003
Cr	0.002	0.001	0.003	0.005	0.003	0.007	0.004	0.004	0.005
Fe	0.23	0.13	0.27	0.21	0.17	0.25	0.31	0.21	0.4
Mn	0.06	0.05	0.07	0.03	0.02	0.04	0.04	0.04	0.05
Ni	0.09	0.08	0.11	0.026	0.023	0.03	0.046	0.039	0.051
Pb	0.002	0.002	0.002	0.001	0.001	0.001	0.002	0.002	0.002
Zn	0.034	0.021	0.044	0.054	0.043	0.062	0.37	0.033	0.041

. When comparing the two rivers, it is evident that the Steelpoort river exhibits higher contamination levels of selected elements compared to the Blyde river. The elevated concentrations of PTEs such as Cr, Fe, and Zn, in the Steelpoort river are likely associated with land use activities, especially the mining and smelting of ferrochrome in the region. In contrast, the relatively higher As levels in the Blyde river may be attributed to the use of fertilizers and pesticides associated with intensive citrus farming in certain areas of the catchment (17).

3.2. Chronic Daily Intake (CDI)

The chronic daily intake (CDI) of the assessed PTEs in the Blyde and Steelpoort rivers is presented in

Table 4. Chronic daily intake (CDI) values of PTEs in water from the Blyde and Steelpoort rivers through ingestion and dermal absorption pathways.

Element	Blyde River	Steelpoort River	Blyde River	Steelpoort River	Blyde River	Steelpoort River	Blyde River	Steelpoort River
	Ingestion				Dermal
	Adult	Adult	Child	Child	Adult	Adult	Child	Child
As	2.0 × 10−4	1.3 × 10−4	8.0 × 10−4	5.0 × 10−4	3.0 × 10−6	1.3 × 10−6	6.0 × 10−6	3.2 × 10−6
Cr	2.0 × 10−4	1.1 × 10−4	7.0 × 10−4	4.0 × 10−4	4.0 × 10−6	2.4 × 10−6	1.0 × 10−5	3.0 × 10−6
Fe	1.3 × 10−4	8.0 × 10−3	5.0 × 10−3	3.0 × 10−2	1.0 × 10−5	8.2 × 10−5	3.0 × 10−5	2.0 × 10−4
Mn	1.5 × 10−3	1.4 × 10−3	6.0 × 10−3	5.0 × 10−3	2.0 × 10−5	1.4 × 10−5	4.0 × 10−5	3.4 × 10−5
Ni	2.4 × 10−3	1.8 × 10−3	1.0 × 10−2	7.0 × 10−3	1.0 × 10−4	7.4 × 10−5	2.0 × 10−4	1.8 × 10−4
Pb	4.0 x10−5	5.0 × 10−5	2.0 × 10−4	2.0 × 10−4	2.0 × 10−6	2.2 × 10−6	2.0 × 10−6	5.3 × 10−6
Zn	3.0 × 10−4	1.3 × 10−4	1.2 × 10−3	5.0 × 10−3	2.0 × 10−5	8.0 × 10−5	5.0 × 10−5	1.9 × 10−4

. The highest CDI values for ingestion were recorded for Ni in the Blyde river, with 0.0024 mg/kg/day for adults and 0.01 mg/kg/day for children. In the Steelpoort river, the highest CDI values for ingestion were recorded for Fe, with 0.008 mg/kg/day for adults and 0.03 mg/kg/day for children. For dermal exposure, the highest CDI values for Fe in the Blyde river were 0.0001 mg/kg/day for adults and 0.0002 mg/kg/day for children, while in the Steelpoort river, they were 0.00008 mg/kg/day for adults and 0.0002 mg/kg/day for children.

3.3. Human Health Risk Assessment

3.3.1. Non-Carcinogenic Risk

The two pathways of exposure for selected PTEs in drinking water through ingestion and dermal routes from the Blyde and Steelpoort rivers were determined for adults and children to assess the potential effects on human health. The hazard quotient (HQ) ingestion values vary from 1.86 × 10⁻⁴ to 6.67 × 10⁻¹ in adults and from 4.00 × 10⁻³ to 2.6667 in children in the Blyde river. In the Steelpoort river, HQ ingestion values vary from 4.33 × 10⁻⁴ to 4.33 × 10⁻¹ in adults and from 1.67 × 10⁻² to 1.6667 in children (

Table 5. Hazard quotients (HQ) and hazard index (HI) values for adults and children for each element in water from the Blyde and Steelpoort rivers.

Element	HQ ing		HQ der		HI = ΣHQs
Blyde River	Adult	Child	Adult	Child	Adult	Child
As	6.67 × 10−1	2.67 × 10	2.44 × 10−2	4.89 × 10−2	6.91 × 10−1	2.72 × 10
Cr	6.66 × 10−2	2.33 × 10−1	2.67 × 10−1	6.67 × 10−1	3.34 × 10−1	9.00 × 10−1
Fe	1.86 × 10−4	7.14 × 10−3	2.22 × 10−4	6.70 × 10−4	4.08 × 10−4	7.81 × 10−3
Mn	1.07 × 10−2	4.29 × 10−2	2.08 × 10−2	4.17 × 10−2	3.15 × 10−2	8.46 × 10−2
Ni	1.20 × 10−1	5.00 × 10−1	1.25 × 10−1	2.50 × 10−1	2.45 × 10−1	7.50 × 10−1
Pb	2.86 × 10−2	1.43 × 10−1	4.76 × 10−3	4.76 × 10−3	3.34 10−2	1.48 × 10−1
Zn	1.00 × 10−3	4.00 × 10−3	3.33 × 10−4	8.3 × 10−4	1.33 × 10−3	4.83 × 10−3
Steelpoort River
As	4.33 × 10−1	1.67 × 10	1.06 × 10−2	2.60 × 10−2	4.44 × 10−1	1.69 × 10
Cr	3.67 × 10−2	1.33 × 10−1	1.60 × 10−1	2.00 × 10−1	1.97 × 10−1	3.33 × 10−1
Fe	1.14 × 10−2	4.29 × 10−2	1.82 × 10−3	4.44 × 10−3	1.32 × 10−2	4.73 × 10−2
Mn	1.00 × 10−2	3.57 × 10−2	1.46 × 10−2	3.03 × 10−2	2.46 × 10−2	6.60 × 10−2
Ni	9.00 × 10−2	3.50 × 10−1	9.25 × 10−2	2.85 × 10−1	1.83 × 10−1	6.35 × 10−1
Pb	3.57 × 10−2	1.43 × 10−1	5.24 × 10−3	1.26 × 10−2	4.09 × 10−2	1.56 × 10−1
Zn	4.33 × 10−4	1.67 × 10−2	1.37 × 10−3	3.17 × 10−3	1.80 × 10−3	1.99 × 10−2

). The HQ through ingestion exceeded 1 for As and Cr in children in the Blyde river and exceeded 1 for As in children in the Steelpoort river. These elements can pose potential adverse health effects when the HQ value of an element is higher than 1 [30]. Thus, there is evidence of non-carcinogenic risk related to As and Cr in children. HQ dermal values vary from 2.22 × 10⁻⁴ to 6.67 × 10⁻¹ in adults and from 6.70 × 10⁻⁴ to 6.67 × 10⁻¹ in children in the Blyde river. In the Steelpoort river, HQ dermal values vary from 1.37 × 10⁻³ to 1.60 × 10⁻¹ in adults and from 4.44 × 10⁻³ to 2.85 × 10⁻¹ in children. All HQ dermal values were below 1, indicating no potential non-carcinogenic risk related to any of the elements. Thus, the HQ values through dermal exposure indicate negligible health risk in adults and children. However, the hazard index (HI) values for As in children were greater than the threshold value of 1 in both rivers (Table 4). Hence, there is non-carcinogenic adverse effect for As in children. A higher index of PTEs than the threshold value (HI > 1) has also been reported in other mining areas [33].

3.3.2. Carcinogenic Risk (CR)

The cancer slope factor (CSF) values vary depending on the specific PTEs and are established for various exposure pathways. Unlike the reference dose (RfD), not all elements have CSF values, indicating that only certain elements have carcinogenic effects. Cancer risk was calculated based on the intake levels of As, Cr, Ni, and Pb, which may increase carcinogenic effects depending on the exposure dose and duration. In general, cancer risks lower than 1.0 × 10⁻⁶ are considered negligible, risks above 1.0 × 10⁻⁴ are considered unacceptable, and risks between 10⁻⁶ and 10⁻⁴ are generally considered acceptable [22,34]. The estimated cancer risk (CR) ingestion exposure values for adults ranged from 3.40 × 10⁻⁷ to 4.08 × 10⁻³ and from 1.70 × 10⁻⁶ to 1.70 × 10⁻² for children in the Blyde river. In the Steelpoort river, values ranged from 4.25 × 10⁻⁷ to 3.06 × 10⁻³ for adults and from 1.70 × 10⁻⁶ to 1.19 × 10⁻² for children. For estimated CR dermal exposure, only As and Cr were considered. In the Blyde river, CR dermal values ranged from 1.10 × 10⁻⁵ to 8.00 × 10⁻⁵ for adults and from 2.19 × 10⁻⁵ to 2.00 × 10⁻⁴ for children, while, in the Steelpoort river, values ranged from 4.76 × 10⁻⁶ to 4.80 × 10⁻⁵ for adults and from 1.17 × 10⁻⁵ to 6.00 × 10⁻⁵ for children. In the Blyde river, the CR ingestion levels of As and Ni exceeded the threshold for adults, and As, Cr, and Ni exceeded the threshold value for children (

Table 6. Carcinogenic risk assessment of PTEs in water from the Blyde and Steelpoort rivers through ingestion and dermal absorption pathways.

Element	Cancer Risk Ing	Cancer Risk Dermal	$\sum$CR	Cancer Risk Ing	Cancer Risk Dermal	$\sum$CR
Blyde River	Adult	Adult		Child	Child
As	3.00 × 10−3	1.10 × 10−5	3.01 × 10−3	1.20 × 10−3	2.19 × 10−5	1.22 × 10−3
Cr	1.00 × 10−4	8.00 × 10−5	1.80 × 10−4	3.50 × 10−4	2.00 × 10−4	5.50 × 10−4
Ni	4.08 × 10−3			1.70 × 10−2
Pb	3.40 × 10−7			1.70 × 10−6
Steelpoort River
As	1.95 × 10−4	4.75 × 10−6	1.99 × 10−4	7.5 × 10−4	1.17 × 10−5	7.62 × 10−4
Cr	5.50 × 10−5	4.80 × 10−5	1.03 × 10−4	2.00 × 10−4	6.00 × 10−5	2.60 × 10−4
Ni	3.06 × 10−3			1.19 × 10−2
Pb	4.25 × 10−7			1.70 × 10−6

).

Similarly, in the Steelpoort River, the CR ingestion of As and Ni exceeded the threshold value for adults, and As, Cr, and Ni exceeded the threshold for children. The dermal CR of Cr only exceeded the threshold value for children in the Blyde river. Chronic exposure to As, Cr, and Ni can lead to various toxic effects on human health.

Considering the carcinogenic risk posed by the cumulative effects of the elements under investigation (ΣCR), both adults and children face potential hazards. However, children are particularly vulnerable to carcinogenic risks, as the cumulative risk exceeded acceptable levels (1.0 × 10⁻⁶ to 1.0 × 10⁻⁴). This result clearly indicates that children are more vulnerable to health risks associated with drinking water contaminated with PTEs than adults. Similar findings have been reported in other studies [33,35]. Similar studies highlighting the elevated risk of children to chemical contaminants in water have been reported [29,32,36]. The Blyde river is surrounded by agricultural activities, while the Steelpoort River is primarily influenced by mining activities, and their effluents contribute to increased concentrations of elements in the water. Catchments near mining sites or industrial facilities are particularly susceptible to PTE contamination. Mining operations can expose elements stored in soil and rock, leading to increased concentrations in nearby water bodies. Agricultural practices often involve the use of fertilizers and pesticides, some of which may contain elements such as As and Pb [37]. Erosion from agricultural fields can mobilize these metals into nearby water bodies. In addition, urbanization also contributes to the pollution of elements through runoff from industrial activities and domestic waste [38].

3.3.3. Limitations of This Study

This study acknowledges some limitations that may affect the accuracy and applicability of its findings. One key limitation is that the analysis of health risks presented throughout this study is largely general in nature and does not consider the specific characteristics and conditions of the local communities within the study area. This generalized approach may overlook significant factors that can influence health risks in the local communities. To enhance the robustness of future research, it is imperative that subsequent studies incorporate a more localized perspective in the risk analyses. This can help in tailoring interventions that are more relevant and effective for specific local populations. There is also a need for longitudinal studies to observe changes over time in health risk outcomes post-intervention, and creating processes for reassessing risks as new data or technologies emerge.

4. Conclusions

The health risk assessment indices, such as hazard quotient for ingestion (HQ_ing) and chronic daily intake (CDI), were found to be near the safe limit (unity), indicating that the risk via the ingestion route may be significant. Conversely, the levels of HQ_derm were less than unity, suggesting that risk may occur via the ingestion route only. Overall, the non-carcinogenic health risk assessment, indicated by hazard index for ingestion (HI_ing) near unity, pointed to significant risk via the ingestion route, while the dermal contact of water from the rivers was much lower than unity and was considered safe (HI_derm < 1). The risk assessment indicated that As and Cr were major contributors to non-carcinogenic health risks. Water samples from the rivers showed carcinogenic risk (CR_ing) associated with slightly elevated values of As, Cr, and Ni. As and Ni indicated potential carcinogenic risk, as the calculated risk was higher than 1.0 × 10⁻⁴. Therefore, this study concludes that significant health risks are associated with the water of the Blyde and Steelpoort rivers. This study revealed that both rivers had higher concentrations of these PTEs than permissible limits, with children being at higher cancer risk than adults. This poses serious health problems, both non-carcinogenic and carcinogenic, to the rural communities relying on these water resources for drinking water, especially children. This study recommends that awareness campaigns aim to educate the public about the significance of water quality, conservation, and sustainable management while highlighting the health risks associated with poor water management. By linking water quality to health outcomes, they drive public interest in improving water management. Collaboration among the community and different stakeholders can lead to more effective campaigns and policies, improving awareness and responses to population health issues. Furthermore, longitudinal studies that would seek to look at how water quality and health change over a certain period are necessary.