Introduction

Water scarcity is a significant problem in many countries in North Africa and the Middle East. Owing to the high population and much-irrigated agricultural land, Egypt has moved to a water-scarce country. Egypt’s primary water source is the Nile River, which receives about 55.5 billion m3 of freshwater; it is about 97% of the renewable water sources (Elbana et al. 2013; El-Agha et al. 2020). In Egypt, wastewater production is about 2.4 billion m3/year, representing a challenge to recycle; most raw wastewater is passing through farmlands. Owing to the limited availability of freshwater, farmers around drainages use it as an alternative source of irrigation for many crops (Egypt State of the Environment Report 2009).

Wastewater contains heavy metals (HM), and repeated irrigation of this water causes the accumulation of HM in agricultural soil. Plants uptake essential and non-essential metals from soil and accumulate in different plant parts. Increasing HM’s content above the permissible food-safe levels contributes to the environmental crisis (Stavrides 2006). Consumption of crops and cereals grown in contaminated soil causes deterioration in human health, especially in children, and increases the possibility of cancer risk (Lu et al. 2015; Qu et al. 2016; Parihar et al. 2021). Heavy metals are non-biodegradable and have a long half-life, and can bioaccumulate in the human body. Exposure to such metals could cause many health problems like changes in blood pressure, dysfunction of the liver, lung, and kidney, and immune system defects (Ming-Ho 2005). In the human body, cadmium and lead have no physiological roles and are linked with disorders of the liver, kidney, and nervous system (Järup 2003). To sustain normal development and maintenance of human physiology, trace essential metals such as zinc and copper are required for living organisms at low concentrations, but excessive exposure to these elements poses human health risks (Nriagu et al. 2009).

From the last century, there is public concern about food safety, and many studies are concerned with the assessment of foodstuffs grown in polluted soil because it is associated with human health risks (Guadie et al. 2021; Haque et al. 2021; Kharazia et al. 2021; Natashaa et al. 2021; Román et al. 2021; Zakir et al. 2020). In Egypt, several studies have explored the assessment of human health hazard and detection of HM in fish (Issa et al. 2018; Masoud et al. 2007), different foodstuffs (Badwey et al. 2014; Farrag et al. 2016), squash (Galal 2016), wheat and maize (Farahat et al. 2017), fruits (Amer et al. 2019), meat from camel, cattle, buffalo, and sheep (Morshdy et al. 2018), and soft drinks (Ghuniem et al. 2020).

The aims of this work are the following: (1) to monitor the bioaccumulation and HM content in water, soil, and plant parts sampled from various treated wastewater and freshwater irrigated farmlands, (2) to evaluate the chronic daily intake (CDIM) of tested HM for children and adult residents via the intake of edible parts, and (3) to assess the non-carcinogenic risk and human health hazards linked by HM accumulation via consumption of foodstuffs irrigated with treated wastewater (TWW). The findings will provide valuable data for further examining HM contents in foodstuffs, thus improving residents’ food safety and health. The outcome of this work is expected to afford an essential contribution to policymakers in Egypt concerning the use of TWW for irrigation foodstuff.

Materials and methods

Site descriptions

This study was performed during May 2018 and June 2019 in two sites. The first site was located in El-Saff city’s cultivated area (Helwan, Cairo Governorate, Egypt). According to local farmers, this site has been exposed to TWW irrigation of crops for over 40 years. The water originates from the sewage treatment station at Helwan.

Helwan Sewage Treatment Plant (HSTP) was located near the industrial area of Helwan city (iron and steel factory, coke, weaving, and fertilizer industries). Those industrial activities produce a vast amount of wastes, which is usually dumped into HSTP for treatment. Also, the station receives domestic wastewater from Helwan and 15th May City. After secondary treatment, the effluent is pumped into the El-Saff canal. These areas are cultivated in violation of traditional crops by farmers. The governorate was planned to use this water for planting about 17,000 hectares of tree forest. The second site was located at El-Badrashin (Giza governorate, Egypt), where the fields in this location have been irrigated with water from the Nile River.

According to the Egyptian Meteorological Authority, the studied area climate is subtropical desert, with hot, sunny summer, and a very mild winter. The temperature ranged from 10 to 36 °C. The precipitation is scarce over most of the year, and the annual rainfall does not exceed 25 mm.

Sampling and analysis

Water sampling

Field sampling was conducted from May 2018 and June 2019. Treated wastewater (TWW) samples were collected regularly from six different sites of the TWW canal passing the studied farmlands. At the same time, the Nile River’s water was taken as a control. Water samples were collected from each irrigation source that simultaneously supplies the studied agricultural farmlands as soil and foodstuff sampling. To avoid microbial activity, few drops of nitric acid (HNO3) were added, and samples were taken to the laboratory for analysis.

Soil sampling

In a contaminated site, composite soil samples were collected from different farms (6 farms, covering 8 ha) irrigated with the El-Saff canal (TWW). Also, soil samples from a reference site (2 farms) were taken. Ten profiles were selected randomly within each farm for each soil sample, where soil samples were sampled at 0–30 cm. The soil was stored in polyethylene bags, air dried, sieved in 2 mm, and stored for analysis from each sampling point.

Plant samples

At the harvest stage, 24 composite samples from different plants were collected randomly from both studied sites. These plants are radish (Raphanus sativus L.), tomato (Solanum lycopersicum L.), lettuce (Lactuca sativa L.), onion (Allium cepa L.), turnip (Brassica raba L.), squash (Cucurbita pepo L.), sunflower (Helianthus annus), Jew’s mallow (Corchorus olitorius), okra (Abelmoschus esculentus L.), and garden rocket (Eruca vesicaria). All the collected plants were thoroughly washed with double distilled water. The samples were cut to separate the roots, shoots, and fruits or seeds. The plant parts were oven-dried until constant weight and then grounded to a fine powder.

Water, soil, and plant analysis

Water samples were analyzed for their pH and electrical conductivity (EC). Nitrogen content was determined as described by Peach and Tracey (1956). Chloride anions (Cl−), chemical oxygen demand (COD), and biological oxygen demand (BOD) were assessed according to APHA (2012). The phosphorous content was determined as described by Rowell (1993). Sodium (Na) and potassium (K+) were determined using a flame photometer (PFP 7, Jenway, UK), according to AOAC (2000).

Soil extracts (1:2.5, w/v) were used to determine pH, EC, and chloride according to Richards (1954) and Jackson (1967). Total carbonate was determined according to Piper (1950). Soil texture was analyzed by the pipette method as outlined by Kilmer and Alexander (1949). Organic matter (OM) was determined following the method of Nelson and Sommers (1982). The total content of Cd, Cu, Cr, Pb, and Zn in the filtered extracts obtained from samples digested by concentrated HNO3, concentrated H2SO4, and 60% HClO4 was analyzed as outlined by Hesse (1971). The soil chemical-extractable contents of these elements were extracted using DTPA (diethylene triamine pentaacetic acid) to determine available HM content according to Lindsay and Norvell (1978).

Plant tissue powder (0.5 g) was digested according to Norvell (1984) using a mixture of H2SO4, HNO3, and HClO4 to quantify select essential elements and HM.

Heavy and essential metals Cd, Cu, Cr, Pb, and Zn in filtrate water, soil, and plant samples were analyzed using Inductively Coupled Argon Plasma (ICAP 6500 Duo, Thermo Scientific, England). A 1000 mg/L multi-element certified standard solution (Merck, Germany) was used as a stock solution for instrument standardization.

Data analysis

  • Soil Pollution Load index (SPLI) was evaluated using Eq. (1)

    $$ \mathrm{SPLI}=\mathrm{Cp}/\mathrm{Cup} $$
    (1)

Whereas Cp and Cup is the HM content in polluted and unpolluted soil (Liu et al. 2005).

  • Heavy metal transfer factor (HMTF), the proportion of metal content in foodstuff (Cfoodstuff; D.Wt.) to metal contents in soil (Csoil), was determined (Mirecki et al. 2015) according to Eq. (2)

    $$ \mathrm{HMTF}={C}_{\mathrm{foodstuff}}/{C}_{\mathrm{soil}} $$
    (2)

  • Chronic daily intake of metals (CDIM) for each metal was assessed using Eq. (3)

    $$ \mathbf{CDIM}=\left({\boldsymbol{C}}_{\mathbf{m}}\times {\boldsymbol{C}}_{\mathbf{f}}\times {\boldsymbol{D}}_{\mathbf{f}\mathbf{i}}\right)/{B}_{\mathrm{aw}} $$
    (3)
    Cm:

    is the HM content in foodstuff (mg kg−1), Cf is the conversion factor 0.085, Dfi is a daily intake of foodstuff with 0.232 and 0.345 kg−1 day−1 for children, and adults, respectively. Baw is the average body weight with 32.7 and 55.9 kg for children and adults, respectively (Rattan et al. 2005).

  • Health risk (HR) was determined according to Eq. (4)

    $$ \mathbf{HR}=\mathbf{CDIM}/{\boldsymbol{R}}_{\mathbf{fD}} $$
    (4)
    CDIM:

    is calculated from Eq. (3), and oral reference doses (RfD) are 0.001, 0.04, 1.5, 0.04, and 0.3 mg kg−1 day−1, respectively, for Cd, Cu, Cr, Pb, and Zn, respectively (US EPA 2018). For HR less than 1, foodstuff are considered to be safe to the local people health.

  • Health hazard index (HI) is the sum of HR for all metals in each crop grown in the study area. The HI was predicated from Eq. (5) (Antoine et al. 2017; Weber et al. 2019).

$$ \mathbf{HI}=\mathbf{\sum}\mathbf{HR} $$
(5)

Statistical analysis

The Q-cluster analysis was performed on the tested HM in different plants (Fig. 1). In this analysis, the square Euclidean distance was considered a measurement interval, and the farthest neighboring element was applied.

Results and discussion

Treated wastewater and freshwater characteristics

Six water samples were obtained from TWW and FW sites for measuring different chemical quality indicators (Table 1). According to Egyptian governmental law and the Food Agriculture Organization (FAO), the pH and EC levels were below the permissible limits. The mean pH and EC for TWW were 7.87 and 1.53 dsm−1, respectively, and those for FW were 7.40 and 1.14 dsm−1, respectively. The obtained data were in line with the finding obtained by Osman et al. (2010) and Farrag et al. (2016) for the El-Saff canal. Total dissolved salts (TDS) ranged between 700–1900 and 137–350 mg L−1, respectively, in TWW and FW. The mean TDS levels in TWW were below FAO guidelines while surpassing the limits recommended by Egyptian national law.

Table 1 Physiochemical and HM characteristics of TWW and FW used for irrigation (mean ± stdv of 6 samples)
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Chemical oxygen demand (COD) and biological oxygen demand (BOD) are essential quality indicators used to assess the water quality and provide an index of the impact discharged wastewater will have on the receiving environment. Both quality indicators were within the permissible limits recommended by Egyptian standards (Table 1). The same findings were recorded by Farrag et al. (2016) and Gedamy et al. (2012). Among tested anions and cations, PO4 and K were above the permissible levels recommended by FAO. The mean value of PO4 and K in the El-Saff canal were 4.26 and 4.70 mg/L, respectively.

The tested HM content in both FW and TWW did not exceed the FAO and Egyptian standards recommended for irrigation (Table 1). In FW samples, HM contents had the lowest values and fluctuated between (mg/L) 0.0003 to 0.004 for Cd, 0.008 to 0.016 for Cu, 0.0001 to 0.0003 for Cr, 0.006 to 0.012 Pb, and 0.01 to 0.02 for Zn. In TWW samples, tested HM showed the highest levels and ranged (mg/L) between 0.001–0.003 for Cd, 0.02–0.1 for Cu, 0.002–0.004 for Cr, 0.002–0.04 for Pb, and 0.007–0.01 for Zn.

The reported values are in line with Farrag et al. (2016) and Gedamy et al. (2012). Farrag et al. (2016) found that the mean values of Cd, Cr, Cu, Pb, and Zn in the El-Saff wastewater canal were 0.002, 0.002, 0.033, 0.022, and 0.01 mg/L, respectively. Meanwhile, the detected data were less than those obtained by Osman et al. (2010), who found Cd and Zn contents in wastewater canals were 0.16 and 1.50 mg/L, respectively. Even though tested HM values were below the standards levels recommended for irrigation by FAO and Egyptian guidelines. The long irrigation period by such water may cause a detrimental impact on the agricultural soil and potential health risk.

Soil characteristics of tested agriculture sites

Physiochemical characteristics of soil samples taken from both tested sites are presented in Table 2. Soil pH, EC, OM, Cl, and CaCO3 were significantly higher in TWW-irrigated sites than FW-irrigated sites. These findings are consistent with several studies indicated that prolonged irrigation with TWW causes such increases (Alghobar et al. 2014; El-Hassanina et al. 2020; Galal 2016; Rezapour et al. 2019; Gemeda et al. 2021).

Table 2 Values of physiochemical and HM characteristics of TWW-irrigated and FW-irrigated sites (mean ± stdv of 6 samples)
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Heavy metals values of Cd, Cu, Pb, Cr, and Zn in soil irrigated by TWW had multiple folds compared with soil irrigated with FW. Tested metal values in both tested sites had the following order: Zn> Cu> Pb> Cr> Cd. The metal values of Cd, Cu, Cr, Pb, and Zn in the TWW-irrigated sites were 2.40, 77.55, 7.00, 53.75, and 83.90 mg kg−1, respectively, while in FW-irrigated sites were 0.51, 3.65, 1.22, 3.92, and 21.00 mg kg−1, respectively (Table 2). Identical findings were recorded by Alghobar et al. (2014), Farahat et al. (2017), Farrag et al. (2016), and Guadie et al. (2021). El-Hassanina et al. (2020) reported that irrigation of agriculture soil by low-quality water significantly increased Pb and Cd many folds (2.4–3.0 folds) compared to those irrigated by FW.

The soil pollution load index (SPLI) of the tested metals was greater than 1, the maximum SPLI (21.25) was for Cu, and the minimum (4.00) was for Zn (Table 2). Relatively high HM levels in TWW-irrigated soils may be ascribed to anthropogenic activities, excessive usage of fertilizers and pesticides, and smelter deposition in more than 400 brick factories around the studied site. Meanwhile, in the FW-irrigated sites, slightly high Cu and Zn content may be due to chemical fertilizers and atmospheric deposition.

Tested HM levels for both tested sites (TWW-irrigated and FW-irrigated sites) were below the limit according to FAO/WHO (2007) and EU (2002). The safe limit values of tested metals in polluted agriculture soils could be attributed to the cultivation and rotation of different crops in such agricultural soils to remove such metal (Chauhan and Chauhan 2014).

Heavy metal contents in the cultivated plants

Tested HM contents in different parts of plants cultivated in both tested sites are presented in Table 3. In the TWW-irrigated sites, Cd, Cu, Cr, Pb, and Zn levels were higher than grown in the FW-irrigated sites. Levels in Cd, Pb, and Zn in the polluted site were surpassed the permissible limits, 0.5, 5.00, and 60 mg kg−1, respectively, according to WHO/FAO (2007), while Cr and Cu contents were below the permissible levels, 5 and 40 mg kg−1, respectively.

Table 3 HM contents (mg kg−1) in different parts of plants grown in TWW-irrigated and FW-irrigated sites (mean ± stdv of 12 samples)
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Q-cluster analysis was carried out on ten plant species grown in TWW-irrigated sites. The HM concentrations in the ten plant species were divided into two main groups: the first contained squash, Jews mallow, tomato, onion, and sunflower plants in ascending order. The second contained radish, lettuce, turnip, garden rocket, and okra plants in ascending order. This group could be classified into two subgroups: (radish–lettuce) and (turnip–garden rocket–okra). Cluster analysis showed that the highest HM contents were in tomato and sunflower among the studied foodstuffs (Fig. 1). The cluster analysis results were consistent with the content analysis conclusions.

Fig. 1
figure 1

Cluster analysis of ten plants grown in TWW-irrigated sites

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For both sites, HM accumulation in various plant parts was in descending order Zn > Cu > Pb > Cd > Cr. Among plant parts, levels of HM in the edible parts grown in polluted site followed the order: tomato > sunflower > Jew’s mallow = turnip = squash > lettuce > okra = radish > onion > garden rocket. Variation in HM levels in plants grown under identical environmental conditions could be attributed to differences in the growing cycle, morphological characteristics, and their ability to accumulate, retain, and exclude metals uptake (Kumar et al. 2009; Demim et al. 2013).

Among parts of plants grown in the polluted site, the highest levels Cd, Zn, and Cu were detected in sunflower shoot, and seed (5.34, 68.3, and 37.2 mg kg−1, respectively), whereas the highest Cr and Pb were found in squash shoot (4.83 mg kg−1) and tomato root (30.3 mg kg−1), respectively. On the other hand, in the FW-irrigated site, the highest Cd and Cu were found in tomato root (0.71 and 2.18 mg kg−1), while the highest Cr, Pb, and Zn were detected in radish root (0.33 mg kg−1), okra root (2.27 mg kg−1), and sunflower seed (12.4 mg kg−1).

The obtained data were similar to those mentioned by Badwey et al. (2014), who reported that the mean HM contents in grains of maize and rice and fruits of guava, pepper, eggplant, palm, okra, and beetroot irrigated from the Bahr El-Baqar drain were 4.18–17.50 mg kg−1 for Cr, 2.75–34.7 mg kg−1 for Cu, and 65.1 mg kg−1 for Zn (on dry weight bases). On the other hand, the data obtained from this work are lower than those obtained by Galal (2016), who detected that Pb was 244.5–280.67, Cd was 4.62–61.6, Cr was 3.98–4.62, Cu was 75.7–132.5, and Zn was 1545–1686 mg kg−1 in squash irrigated by industrial effluents. Our results were also higher than those previously reported (El-Hassanina et al. 2020; Farrag et al. 2016).

Chronic daily intake of metals, health risk, and health hazard index

In Egypt, low-quality water is widely used for crop irrigation due to water scarcity. Assessment of human health risk is of vital importance. The mean calculated values of CDIM and HR for plants consumed by children and adults are presented in Tables 4 and 5. The mean chronic daily intake of metals (CDIM) values of plants irrigated by TWW water were higher than plants irrigated by FW. Guadie et al. (2021), Mahmood and Malik (2014), and Massaquoi et al. (2015) also documented higher CDIM values in wastewater-irrigated farmlands than in FW-irrigated farmlands. The highest CDIM in both children and adults were detected for Zn as 0.035 and 0.028, respectively (Table 4).

Table 4 Chronic daily intake of HM (CDIM; mg person−1 day−1) from plants grown in TWW-irrigated and FW-irrigated sites
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Table 5 Health risk (HR; mg person−1 day−1) from plants grown in TWW-irrigated and FW-irrigated sites
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In TWW-irrigated site, the CDIM values in adults of Pb for radish, lettuce, tomato, onion, turnip, squash, okra, sunflower, Jews mallow, and garden rocket were 1.01E − 02, 8.40E − 03, 1.18E − 02, 5.95E − 03, 1.12E − 02, 1.01E − 02, 7.07E − 03, 1.19E − 02, 1.04E – 02, and 7.54E − 03, respectively. In children, the values were 1.16E − 02, 9.65E − 03, 1.35E − 02, 6.84E − 03, 1.29E − 02, 1.17E − 02, 8.13E − 03, 1.36E − 02, 1.20E – 02, and 8.66E − 03, respectively. Children had higher risks than adults, and the CDIM values were higher for children than adults. The same finding was reported by Huang et al. (2018) and Hussain and Qureshi (2020). Among different plants, sunflower showed the highest risk to human health, followed by squash, turnip, and Jews mallow.

Health risk (HR) has been considered a valuable parameter for assessing the risk associated with consuming contaminated food crops (Sridhara Charya et al. 2008). One of HM’s most notable exposure routes to humans is the food chain via vegetable intake (Muchuweti et al. 2006). In the plants irrigated with FW, HR values were lower than plants irrigated with TWW (Table 5). For adults and children, all HR values for all HM in foodstuff grown in farmlands irrigated with FW was <1, indicating that the foodstuff safe for consumption. Meanwhile, HR for plants irrigated with TWW were mostly <1, except for Cd> 1, suggesting possible exposure to Cd toxicity for local consumers (Table 5). Comparable results were reported following evaluation for a field irrigated with TWW in Dubi, UEA (Qureshi et al. 2016), and farmlands irrigated with TWW in western Azerbaijan province, Iran (Rezapour et al. 2019). Cadmium is a non-essential metal and, at very low content, had harmful impacts on human health. Exposure to Cd could cause chronic diseases like liver and kidney dysfunction, and human tissue accumulation causes cancer. In the present study, higher HR values were detected in children than adults, which could be attributed to children’s behavioral habits that increase skin contact possibility (Huang et al. 2018).

The health hazard index (HI) has to be <1 to pose any health risk, while when HI is >1; there could be possible health hazards associated with overexposure (USEPA 2006). In this work, the order of HI for plants grown in TWW-irrigated sites was lettuce > radish = turnip > okra > sunflower > Jews mallow > squash > tomato > onion > garden rocket for adults, while the HI sequence for children was lettuce > tomato = sunflower > radish > Jews mallow > okra = turnip > squash > onion > garden rocket (Table 6).

Table 6 Mean health index (HI) of plants grown in TWW-irrigated sites
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The comparative contributions to the aggregated potential risk of radish, lettuce, tomato, onion, turnip, squash, okra, sunflower, Jews mallow, and garden rocket were 11.0, 12.6, 9.36, 8.12, 11.0, 9.54, 10.7, 10.1, 9.68, and 7.66, respectively. Garden rocket and onion have a low HI percentage revealed a low health hazard to consumers (Table 6).

Sanaei et al. (2021) found that the health hazard index HI in different foodstuffs consumed by the residents in Isfahan (Iran) was 2.98, 4.08, and 6.91 for adults, teens, and children, respectively. This reflects the potential threat for all communities, particularly children. In this context, regular observation of these metals in agricultural foodstuff in the studied sites is essential for preventing excessive accumulation of metals in the food web.

Heavy metal transfer factor

Plants irrigated with TWW showed higher HMTF than plants irrigated with FW, and Cd has the highest HMTF than other tested metals (Table 7). Among different plants grown in TWW-irrigated sites, the HM transfer factor was maximum in Jews mallow and okra. In Jews mallow, HMTF take the following order Cd (1.513) > Zn (0.638) > Pb (0.370) > Cr (0.297) > Cu (0.257). Meanwhile, among plants irrigated with FW, the highest HMTF was found in okra. In okra, HMTF was in order Cu (0.595) > Zn (0.548) > Pb (0.421) > Cd (0.176) > Cr (0.139).

Table 7 Metal transfer factor of plants grown in TWW-irrigated and FW-irrigated sites
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Heavy metal transfer factor (HMTF) values were varied among various plants. It could be attributed to variations in soil metal levels, plant species, and metal (Cui et al. 2004). Extensively, HMTF values were varied among the edible parts of tested plants grown in TWW-irrigated sites and fluctuated between 0.120 and 1.650. Simultaneously, HMTF ranged from 0.022 to 0.600 in the edible parts of tested plants grown in FW-irrigated sites (Table 7). Rehman et al. (2019) found that heavy metal transfer factor (MTF) was higher in mustard, carrot, turnip, cabbage, spinach, and cauliflower grown in farmlands irrigated with wastewater than in farmlands irrigated with groundwater and was higher for Fe and Ni than for other tested metals (Pb, Cd, Cu, Zn, and Mn).

In all tested plants grown in both tested sites, the HMTF was a maximum in Cd followed by Zn (Table 7). It could be attributed to low retention and high metal mobility in the soil (Lokeshwari and Chandrappa 2006). The main module for human exposure to HM through the food chain is the metal transfer from soil to edible parts in the plant. HMTF is fundamental to examine risk index for human health (Cui et al. 2004)

Conclusion

The main objective of this work was to assess the levels of five HM (Cu, Cd, Cr, Pb, and Zn) in ten highly consumed plants (radish, lettuce, tomato, onion, turnip, squash, okra, sunflower, Jews mallow, and garden rocket) grown in a field farms irrigated with TWW and FW in Southern Cairo (Egypt). The HR and HI were also evaluated. The levels of tested HM in FW and TWW were below the FAO and the Egyptian standards. In soil samples, HM levels were below the permissible limits for tested sites. The HM levels in soil and plants grown in TWW-irrigated sites possessed multiple levels than those grown in FW-irrigated sites.

The most critical and worst scenario was considered: the consumption of all contaminated foodstuffs by local consumers. For the children, HR level was above the permissible limit only for Cd for all tested foodstuffs, and high HR levels were detected in lettuce, tomato, and sunflower. Simultaneously, for adults, these levels were less than detected in children.

According to this work, there is currently no health risk of HM toxicity resulting from human consumption of tested foodstuff irrigated with TWW, except for Cd. Routine monitoring of HM levels in TWW, soil, and foodstuff should be performed to prevent potential exposure and associated health hazards. Moreover, some suitable and practical solutions include the tertiary treatment of wastewater and management practices such as mixing TWW with fresh water. Implications refer to the need for actions for spreading public awareness, particularly concerning health risks are needed.