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Assessment of Groundwater Contamination in the Southeastern Coast of Brazil: A Potential Threat to Human Health in Marica Municipality

Maria Cristina M. Publio
Jessica F. Delgado
Bruno S. Pierri
Leonardo da S. Lima
Christine C. Gaylarde
José Antônio Baptista Neto
Charles V. Neves
2 and
Estefan M. Fonseca
Programa de Pós-Graduação em Dinâmica dos Oceanos e da Terra, Universidade Federal Fluminense, Niterói 24210-346, RJ, Brazil
Aequor-Laboratório de Inteligência Ambiental, R. Joaquim Eugênio dos Santos, 408-Eldorado, Maricá 24901-040, RJ, Brazil
Department of Microbiology and Plant Biology, Oklahoma University, 770 Van Vleet Oval, Norman, OK 73019, USA
LAGEMAR—Laboratório de Geologia Marinha, Department of Geology and Geophysics, Instituto de Geociências, Universidade Federal Fluminense, Avenida Litorânea s/n, Niterói 24210-340, RJ, Brazil
Author to whom correspondence should be addressed.
Eng 2023, 4(4), 2640-2655;
Submission received: 4 September 2023 / Revised: 10 October 2023 / Accepted: 13 October 2023 / Published: 17 October 2023


Groundwater pollution is a current issue that may result in considerable negative effects on human health and the ecological balance. In the present study, the authors evaluated pollutants in groundwater in Maricá Municipality, located on the east side of Rio de Janeiro state in Brazil. The evaluated parameters were temperature, pH, electrical conductivity, Eh, dissolved oxygen, chlorides, nitrates, dissolved organic carbon, total inorganic carbon, phosphates, and total and thermotolerant coliforms. Due to the large number of evaluated points, they were divided into zones according to the respective hydrographic basin. The local accelerated urbanization accompanying income from oil production has led to uncontrolled population growth and associated groundwater pollution. The results of the present study suggest that sewage pollution of Maricá groundwater is already a significant issue. The lack of investment in basic sanitation has led to an imbalance in the local groundwater reservoir. In certain locations of the municipality, dissolved organic carbon (DOC), nutrient, and bacteria concentrations increase and spread in the aquifers because of domestic waste disposal. As aquifers are the main source of freshwater for the residents, contamination of them represents a potential threat to local public health.

1. Introduction

Groundwater is the largest global source of freshwater, representing a fundamental reservoir for humanity that is exploited for domestic, agricultural, and industrial purposes [1]. About 30% of the Earth’s population uses groundwater as drinking water [2]. It is especially essential in arid and semi-arid areas, where rain is scarce and there are few surface water reserves [3]. Preserving an unpolluted and renewable source of groundwater for human demands represents one of the biggest challenges of sustainable development for every country [4]. This is even more important in the present scenario of global warming and the consequent rise in sea levels, which may result in the salinization of several subterranean water reservoirs located in coastal regions [5]. Additionally, uncontrolled human occupation and agglomeration, excessive urbanization, agricultural and industrial activities, and uncontrolled water exploitation all negatively impact groundwater quality and availability [6].
Groundwater contamination due to organic pollutants such as hydrocarbons and pesticides and inorganic substances like heavy metals, microplastics, and endocrine disruptors poses a substantial threat to human health [7,8]. During the last three decades, several authors have considered the chemical pollution of groundwater [6,9,10,11,12,13]. Although the major pollutants are of geologic origin, resulting from dissolution of the aquifer rock within the Earth’s crust [14,15,16], the recent increase in the world’s population has led to increases in anthropogenic contaminants. The most impacted areas are those that are experiencing rapid economic development [17,18,19]. Several researchers have focused on the impact of megacities on groundwater [20,21], but few scientists have evaluated small coastal cities, where urbanization has recently intensified.
The Brazilian coastal area currently comprises 40% of the country’s total population. Although some coastal cities in Brazil have moderate groundwater demand, the constant population increase tends to intensify groundwater exploitation [22]. Because of the recent discovery of the huge petroleum reservoir in the oceanic pre-salt layer and oil production expansion, certain Brazilian municipalities located on the southeast coastal zones have benefited from fees charged by the oil extraction industry and are now facing new social and environmental impacts [23]. One of the main results is exponential migration and the resulting increase in population accompanying new job opportunities. This has occurred in the coastal city of Maricá.
The present study provides a diagnosis and spatial groundwater chemical and microbiological characterization of wells from sedimentary and fissured aquifers in this recently urbanized coastal area. It discusses contamination and salinization of aquifers, identifying patterns that may be occurring in many recently urbanized coastal regions in Brazil. One of the main objectives of the present study is, through the assessment of groundwater quality in the coastal municipality of Maricá, to inquire about whether the royalty payments from the oil industry to these municipalities have helped mitigate secondary socio-environmental impacts arising from oil production or whether these same payments have generated new problems, particularly in water quality, due to the local population increase resulting from the pursuit of new income opportunities.

2. Study Site

Maricá is a municipality of the Rio de Janeiro metropolitan area, located on the Atlantic coast. Its geology is marked by the presence of metamorphic, igneous, and sedimentary rocks, with great geodiversity. It includes the Jaconé beachrocks, whose sedimentary formations were described by Darwin and are considered natural heritage of high geological, environmental, landscape, and cultural relevance.
The coastal geomorphology of Maricá presents an ecologically important lagoonal system, composed of four main lagoons and two sandy barriers that isolate the coastal system from the adjacent sea. Its sedimentary history, architecture, and evolution took place in the Quaternary. It is composed of six lithological units forming three sedimentary sequences compartmented by erosive surfaces [24]. As for the geological aspects, the coast located to the west of the Cabo Frio point undergoes a sudden inflection, having an east–west alignment, and is called the Coastal Cords coast [21]. In structural terms, it is part of a geological complex composed predominantly of granite and gneiss, represented in the landscape by coastal massifs.
The aquifers found in the area are of the granular type, comprising heterogeneous alluvial deposits and portions of soil and weathered rock. Alluvial sediments are composed predominantly of quartz sands and, subordinately, silty and clayey soils, which occur in the vicinity of the lagoons. These are due to the formation of the coastal lowland during the last transgression and regression movements in the Holocene, between 5000 and 7000 years ago. The coastal lowland is formed by lateral variations parallel to the coastline, with sandy highs and low vegetation typical of restinga and sandy-clay wetlands. These make up the marshes and mangroves in the region. The underground water horizon level is generally near the soil surface, at depths from a few centimeters to a few meters. In the area of the sands, which corresponds to the shallowest places, the water is generally less brackish than in the swampy lowlands [25]. The municipality has groundwater as its main source of freshwater. With the growing demand for water resources underground, supply and contamination problems are expected, in addition to the phenomenon of seawater intrusion in these aquifers. The groundwater resource in the target area has been suffering degradation in its quality in response to the advance of the marine saline wedge, brought about by excessive uncontrolled pumping and organic pollution [25].

3. Methodology

A total of 124 groundwater samples were collected through pre-installed wells already in use by the population in the plain area of the Maricá Basin (Figure 1) during the winter season. The points were divided into nine zones with different urban occupation degrees and with different hydrographic basins. All of the groundwater samples were kept in a portable refrigerator and transported back to the lab at 4 °C to be analyzed within one week. Chemical examination of the groundwater included determination of the temperature, pH, electrical conductivity, Eh, turbidity, dissolved oxygen, dissolved solids, chlorides, nitrates, dissolved organic carbon, dissolved inorganic carbon, phosphates, and total and thermotolerant coliforms. Proper sampling techniques and handling were used to produce high-quality data. Brown glass sampling bottles, which had been previously cleaned with deionized water, underwent a triple rinse with water collected from each sampling location before being used for sampling. Each rinsing cycle utilized a volume of 2.5 L. Subsequently, these bottles were transported to the laboratory within 24 h for preliminary processing. The water samples were analyzed in accordance with the testing procedures outlined in the Groundwater Quality Standard (GB/T 14848-2017 [26]).
The first five parameters (temperature, pH, electrical conductivity, Eh, dissolved oxygen) were measured in situ using a multiparameter Horiba U10 probe. The chloride analysis used back titration with potassium thiocyanate. Dissolved organic carbon (DOC) was determined via the method defined by Van Hall et al. [27]. Interferences from particulate carbon and inorganic carbon were removed before analysis via filtration through glass fiber filters and sparging with CO2-free gas after acidification of the sample [28]. Phosphate and nitrate were analyzed via colorimetric methods.
To determine bacterial levels, water samples were plated on mFC (membrane fecal coliform agar) and typical colonies identified as E. coli with EC-MUG (Escherichia coli-methylumbelliferyl-β-D-glucuronide) medium. The 124 samples obtained during the present study were also evaluated directly for E. coli through modified mTEC (membrane thermotolerant Escherichia coli) agar [29].
Data for all parameters were tested for homoscedasticity and normality before being submitted to one-way ANOVA (variance analyses) to test whether there was a statistical difference between the zones. The Tukey test was used to compare average values when necessary. Pearson’s correlation analysis was performed between the total coliform data and the other parameters. All statistical analyses were performed using the GraphPrism 8.0 software (GraphPad Software—v.10.0.3), accepting 5% variation as significant.

4. Results and Discussion

The chemical constitution of groundwater is directly influenced by the composition of the water percolating the soil, as well as the resulting by-products and kinetically controlled reactions within the aquifer basin and overlying subsoil coverage [30]. As a universal solvent, water mobilizes minerals from the soil and bedrock with which it comes into contact. The physicochemical characteristics of drinking water, on the other hand (temperature, pH, dissolved oxygen levels, conductivity, turbidity, organic matter and NH3, potential contaminants and other chemical constituents), eventually impact its portability, in some cases influencing consumers’ health, possibly as a result of the survival of harmful microorganisms [31].
Surface water temperature controls the metabolism of the aquatic ecosystem. For instance, relatively high water temperatures may reduce its ability to hold essential dissolved gasses like oxygen, potentially killing fish and other water organisms [32]. Variations in groundwater temperature may trigger changes in biogeochemical mechanisms in the subsurface environment, impacting water quality [33,34]. Laboratory assays allow for the identification of processes like carbonate precipitation, silicate dissolution, mobilization of cations, trace elements, and dissolved organic carbon (DOC) [35,36,37,38,39]. In the present study, the temperature values varied between 21.5 and 29.61 °C, with one anomalous record of 35.1 °C (average of 24.83 °C). Opportunistic pathogens, including Legionella spp., can grow in the water systems in buildings, representing a critical public health issue [40,41]. According to World Health Organization, water temperature is important for the control of Legionella spp., and water temperatures should be maintained above 50 °C to prevent the growth of this organism [42].
PH represents one of the main physicochemical parameters influencing the behavior of water-quality parameters as well as pollutant concentrations in aquatic ecosystems [43]. This parameter also influences the communities of bacteria and other microorganisms. In general, relatively high or low pH conditions can make water improper for certain purposes. At higher pH levels, metals tend to precipitate, whereas other compounds like ammonia become toxic to aquatic life, releasing bad odors and tastes [44]. At lower pH levels, heavy metals tend to dissolve, becoming bioavailable, and chemicals like cyanide and sulfide become more toxic. The pH values determined in the present study are presented in Table 1.
Of the 124 sampling stations, 47 showed pH values in disagreement with Brazilian legislation, which represents almost 38% of the monitored points. Every zone had at least two sampling stations presenting values above the minimum allowed by the Brazilian law CONAMA 357/05. It is important to emphasize that the minimum pH value in zone 02 (3.11) is alarming. This value is close to the pH for solutions such as vinegar and orange juice. Additionally, five other sampling stations in zone 02 recorded pH values below 5.00. There was no statistically significant difference in pH values among the zones (p > 0.05).
The U.S. Environmental Protection Agency and the equivalent Arabian legislation suggest that the pH of water sources should be maintained at between 6.5 and 8.5. According to Nasseem et al. (2022), it is better to have greater alkalinity, below 7.0, in human drinking water, since it keeps the water safe for drinking. According to the same authors, acidic water with a pH of less than 6.5 suggests potential contamination with pollutants, making it unsafe for drinking purposes. Additionally, water with a pH < 6.5 could be corrosive, leaching metal ions such as Fe, Mn, Cu, Pb, Ni, Cr, and Zi from the aquifer rocks or transporting piping nets [6]. Throughout the present study, water pH values were more acidic than those acceptable by the legislation, varying at around 6.04, and several times being below 6. In fact, 81 sampling stations (approximately 65%) showed unacceptable pH values.
Dissolved oxygen (DO) levels have a direct impact on groundwater quality by regulating the valence state of heavy metals and the microbial catabolism of dissolved organic compounds [45]. A decrease in dissolved oxygen levels can result in anaerobic patterns, which negatively impacts aquatic organisms. The organic matter potentially released from surface sources through a groundwater reserve, on the other hand, can rapidly decrease the dissolved oxygen in the groundwater, turning it into a reducing underground environment more susceptible to the dissolution of the Fe and Mn that compose the aquifer rocks [46]. The Brazilian law CONAMA 357/05 suggests a minimum dissolved oxygen concentration of drinking water of 6.00 mg·L−1. In the present study, the recorded oxygen levels (Figure 2) suggest a high oxygen demand in some zones. Zones 05 and 07 showed DO concentrations of 4.21 and 4.93 mg·L−1, respectively. On the other hand, the other seven zones did not suggest a high oxygen demand, with DO concentrations varying at around 6 mg/L. When we compared the DO concentration of zones 05 and 07 with that in zone 08, we found a statistically significant difference between them.
The dissolved organic carbon (DOC) sometimes showed high concentrations, especially in the most urbanized zones. The DOC averages varied. All zones had at least two collection points whose values exceeded the CONAMA 357/05 limit of 10 mg·L−1. Only one zone (zone 03) had an average value above the maximum allowed by law. Approximately 35% of all sampled stations (43 points of all zones) had values above the limits allowed by CONAMA 357/05. Zones 05, 06, 07, and 03 were those with the highest proportion of points above this limit. The summary of the DOC values is shown in Table 2.
The potability of groundwater is directly linked to DOC concentrations, which influence water chemistry and microbial levels [47,48,49,50,51]. As a result, there have been several studies on the concentrations, sources, and diffusion of natural DOC in aquifers [52,53,54]; however, to date, few have focused on human health. DOC consists of the carbon part of dissolved organic matter (DOM), typically representing more than 90% of the whole organic carbon content in natural groundwater reserves [55]. Nevertheless, levels above background concentrations may indicate organic pollution [48,54,56].
Comparing the results of the present study with the Canadian legislation for untreated drinking water (4 mg·L−1 of DOC), we observed that the percentage of points above the allowed value increased to 53.22%, which corresponds to 66 sampling stations. This means that more than half of the water wells would be in unfit condition for consumption according to Canadian legislation.
High concentrations of DOC in water may result in aesthetic and odor problems, in addition to the potential stimulation of pathogenic bacteria [57,58,59]. High DOC levels also result in a significant impact on the geochemical dynamic of other pollutants, such as pesticides, pathogens, and pharmaceuticals; lower oxygen conditions may decrease the degradation of carbon-based compounds [60]. High levels of COD in groundwater may also suggest the development of trihalomethanes in water disinfected with active chlorine. When compared to other environments, the values obtained in the present study were significantly high (Table 3).
In a way similar to that of other substances, chloride in groundwater originates from both geogenic and anthropogenic sources. In the second case, agricultural, industrial, and/or domestic wastes are considered potential causes [69,70]. Chloride concentrations in uncontaminated waters often stay below 10 mg·L−1 and sometimes below 1 mg·L−1. On the other hand, high levels of chlorides are suggestive of pollution [71]. Although they may be present in most freshwater ecosystems, large concentrations are potentially toxic to freshwater organisms. The results are shown in Table 4.
The by-products of chlorine disinfection potentially affect consumers’ health. Their magnitude is influenced by a number of variables, such as period of action, levels, and frequency of exposure. Compared to other locations, the studied area revealed extremely high values. The results found in this study ranged between 11.5 and 1466.2 mg·L−1. The U.S. Environmental Protection Agency (EPA) and the Brazilian legislation recommend a maximum value of 250 mg·L−1 for drinking water. In the present study, several sampling stations recorded values significantly higher than that. Chloride compounds have two main natural sources: soil chloride dissolved during water runoff and seawater intrusion during high tides. An addition of 1% seawater can increase the chloride content to 190 mg·L−1 [72]. Anthropogenic chloride sources are mainly industrial wastewater discharge in densely occupied areas; industrial wastewater and domestic sewage represent significant sources of chloride in water bodies. In the present study, chloride values varied between 1472.4 and 11.5 mg·L−1 (average 154 mg·L−1). Aside from the potential health threats related to high blood pressure, these chloride concentration limits have been established to protect water from tasting salty and to prevent a corrosive effect on plumbing.
Nitrogen and phosphorus levels may indicate wastewater contamination and can be a threat to human health. Excessive levels of nitrate may cause disease. High levels of nitrate in drinking water may decrease blood oxygen transport, resulting in health issues such as blue baby syndrome [73,74]. According to the China Bureau of Quality and Technical Supervision, the acceptable limits of nitrate for drinking groundwater is 20.0 mg·L−1 [3]. In the present study, all values of nitrate remained below these values. Brazilian CONAMA 357 legislation limits the nitrate concentration in drinking water to 10 mg·L−1.
The nitrate concentration found in the present study ranged from 0.00 to 27.98 mg·L−1. Zones 04, 05, and 07 showed 100% of their collection stations, in accordance with CONAMA 357. All zones yielded mean and median values below the maximum allowed by Brazilian law. However, zones 08 and 09 had the highest proportion of points in disagreement, with approximately 15% being above the Brazilian law limits. A summary of the nitrate values can be found in Table 5.
Although the findings for nitrate concentrations were relatively positive, the total organic nitrogen concentration (TON) presented a slightly more worrying scenario. As for nitrate, zone 05 presented 100% of its collection points with TON concentrations in accordance with CONAMA 357. However, zone 09 had the highest average TON, as well as the point with the highest overall concentration (36.23 mg·L−1). Zones 01 and 08 also showed average values above the legal maximum. A total of 50% of the points in Zone 08 had TON concentrations above the legal limit. The ANOVA showed a statistical difference between zone 03 and zones 08 and 09, with zones 08 and 09 presenting TON means significantly higher than that of zone 03 (p < 0.05). The same results were observed for zones 05, 08, and 09, with zones 08 and 09 presenting TON means significantly higher than that of zone 05 (p < 0.05). There was no difference between the other studied areas. Figure 3 presents the statistical analysis across all zones, and Table 6 shows the summary of the TON information for all areas studied.
Phosphorus is a fundamental element for all living beings. However, excessively elevated phosphorus levels can result in eutrophication of surface water. Groundwater, on the other hand, can be an important diffuse source of phosphorus to surface aquatic environments. It is generally accepted that phosphate groundwater concentrations are negligible due to high rates of adsorption to the soil and sediment matrix. In the present study, recorded values of phosphate varied between 2.32 mg·L−1 and the detection limit (<0.01 mg·L−1). The phosphorus concentrations indicated excess phosphorus, with at least 40% of the collection points of all zones being in disagreement with CONAMA 357 (Table 7). Approximately 69% of all zones had values above the CONAMA 357 maximum of 0.02 mg·L−1. The ANOVA showed a statistical difference between zones 01 and 02 and zone 07 (Figure 4), with zone 07 presenting a mean phosphorus concentration that was significantly higher than those of zones 01 and 02 (p < 0.05).
Most pathogenic microorganisms found in water are of fecal origin and are spread via fecal–oral exposure. These pathogenic agents can produce relatively mild gastrointestinal disorders or serious disease such as infectious hepatitis, encephalitis, and myocarditis. Thus, the negative impacts resulting from the consumption of contaminated water on human health can range from low-level infections (mild diarrhea) lasting a few days to critical illnesses that require medical care or even hospitalization, potentially culminating in death [75]. Fecal coliforms constitute a group of relatively harmless microorganisms present in the intestinal tract of warm- and cold-blooded animals that are also involved in the digestive process [76]. Of these, Esterichia coli is the most common representative and indicates that the water is polluted with fecal material from humans or other animals [77].
On the other hand, the mere presence of these organisms, although harmless, may indicate that the water may have been contaminated by pathogenic organisms or disease-causing bacteria or viruses, which may also exist in fecal material. Runoff is the main carrier mechanism of pathogen transport to surface water bodies. During a rainfall event, the water distribution between surface runoff and soil percolation results from many factors: storm water flux and extension, soil physical features (e.g., porosity and permeability), land height gradients, and soil vegetal or urban cover [78]. If rainfall load exceeds the capacity of the soil to absorb water, overland flux occurs, and microorganisms can be transported in surface runoff [79,80].
The results found in the present study suggest significant important contamination of the groundwater with some source of industrial or, mainly, domestic sewage. Brazilian legislation allows the presence of up to 200 MPN (most probable number) of fecal coliforms in water. In the present study only zone 05 did not showed no collection points with values above the legal limit. However, even at concentrations within the permitted limit, all points in zone 05 showed the presence of fecal coliform cells, which suggests contamination with domestic sewage of the groundwater in that zone, even if small. At least 13% of the collected points of the other zones had coliform concentrations above 200 MPN; for example, 4 of the 29 monitoring stations in zone 02 had values above the Brazilian limit. Although in a relatively low proportion (compared to the other zones), the most worrying factor in zone 02 is the presence of highly contaminated samples, with concentrations up to 12 times higher (2400 MPN) than allowed by Brazilian legislation.
The other zones presented a critical scenario, with the proportion of contaminated points ranging from 35.29 to 83.33%. The minimum average value in these zones (01, 03, 04, 06, 07, 08, and 09) was 218 MPN, which is already above the maximum allowed by Brazilian legislation. The worrying maximum average value was 1455 MPN, found in zone 06. In addition to this worrying average, it is important to note that 83.33% of the sampled sites in zone 06 had contamination above the permitted level, further aggravating the magnitude of the problem in that area. Another important fact is that, of all 124 points analyzed, only 7 showed no presence of coliforms. With the exception of zone 05, all other zones had at least 1one point with at least four times more total coliforms than allowed by law. Table 8 presents the summary of the results found for total coliforms in all zones.
Pathogens are released from sewage in the soil; however, most of them remain associated with the fecal deposit. The amount depends on a number of factors, such as the source, age, type, and pathogen level in the fecal matter itself, as well as the survival characteristics of the pathogens. Pathogen survival in water depends on many factors, including water quality (e.g., turbidity, dissolved oxygen, pH, organic matter content) and environmental conditions (e.g., temperature, predation by zooplankton). Exposure to UV light is a key factor in bacterial, viral, and protozoan die-off in surface waters [78,81,82]. An aquifer environment also protects pathogens against UV exposure and facilitates their survival in groundwater. E. coli and fecal enterococci (FE) counts were suggested in some sampling sites. The results of the present study show a strong and positive correlation (p < 0.05) between total coliforms and the concentration of DOC, TON, and phosphorus in groundwater, corroborating possible contamination with domestic sewage. Figure 5 shows the three correlations.

5. Conclusions

Availability of groundwater of good quality is essential for the maintenance of human and animal health, especially in areas with scarce freshwater reservoir availability. This necessary quality can be ensured by regular monitoring and protection of water sources against potential contamination. In the present study, quality evaluation based on the chemical composition of groundwater revealed that the required level of some parameters for human health required by the legislation used around the world is not being met. None of the monitored points had the minimum quality required by Brazilian legislation; all points had at least one parameter in excess. The results of organic matter and fecal coliform evaluations suggest that one of the main sources of pollutants is domestic sewage resulting from a lack of basic sanitation. Additionally, with the exponential population growth observed in the municipality of Maricá and its plans for agro-industrial development, it is expected that the already established conditions will deteriorate significantly, with pollutants of a more recalcitrant and, therefore, more toxic nature being disseminated in the environment. Urgent measures of basic sanitation must be implemented, even before the implementation of an industrial park, as planned by the municipal government, to prevent even more severe impacts from being detected in the near future.
Although only one collection campaign was carried out, it was performed in the winter, when an improvement in groundwater quality is expected. The quality of the local water would be even worse in the summer, when the most intense rains promote greater transport of pollutants to the subterranean compartment.
Groundwater pollution represents a real danger to human communities. There is a great opportunity for the global scientific community to improve existing aquifer management, highlighting its importance to decision-makers and allowing them to understand how we can defend or rescue both the quality and the quantity of these essential resources.

Author Contributions

M.C.M.P.: experiment execution, analysis, and literature review. J.F.D.: experiment execution, analysis, literature review, and writing. B.S.P.: analysis, literature review, and writing. L.d.S.L.: analysis, literature review, and writing. C.C.G.: literature review, English review, and writing. J.A.B.N.: literature review and writing. C.V.N.: analysis and literature review. E.M.F.: supervisor researcher, literature review, and writing. All authors have read and agreed to the published version of the manuscript.


This research was funded by the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) and Companhia de Desenvolvimento de Maricá (CODEMAR).

Institutional Review Board Statement

The Institutional Review Board Statement is not applicable to this study, as it does not involve human or animal testing.

Informed Consent Statement

The Informed Consent Statement is not applicable to this study, as it does not involve human or animal testing.

Data Availability Statement

The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.

Conflicts of Interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as potential conflicts of interest.


  1. Ullah, Z.; Rashid, A.; Ghani, J.; Nawab, J.; Zeng, X.-C.; Shah, M.; Alrefaei, A.F.; Kamel, M.; Aleya, L.; Abdel-Daim, M.M.; et al. Groundwater Contamination through Potentially Harmful Metals and Its Implications in Groundwater Management. Front. Environ. Sci. 2022, 10, 1021596. [Google Scholar] [CrossRef]
  2. International Association of Hydrogeologists. Groundwater—More about the Hidden Resource; International Association of Hydrogeologists: London, UK, 2020. [Google Scholar]
  3. Li, P.; Tian, R.; Xue, C.; Wu, J. Progress, Opportunities, and Key Fields for Groundwater Quality Research under the Impacts of Human Activities in China with a Special Focus on Western China. Environ. Sci. Pollut. Res. 2017, 24, 13224–13234. [Google Scholar] [CrossRef]
  4. Velis, M.; Conti, K.I.; Biermann, F. Groundwater and Human Development: Synergies and Trade-Offs within the Context of the Sustainable Development Goals. Sustain. Sci. 2017, 12, 1007–1017. [Google Scholar] [CrossRef]
  5. Mazhar, S.; Pellegrini, E.; Contin, M.; Bravo, C.; De Nobili, M. Impacts of Salinization Caused by Sea Level Rise on the Biological Processes of Coastal Soils—A Review. Front. Environ. Sci. 2022, 10, 909415. [Google Scholar] [CrossRef]
  6. Saalidong, B.M.; Aram, S.A.; Otu, S.; Lartey, P.O. Examining the Dynamics of the Relationship between Water PH and Other Water Quality Parameters in Ground and Surface Water Systems. PLoS ONE 2022, 17, e0262117. [Google Scholar] [CrossRef]
  7. Li, P. To Make the Water Safer. Expo. Health 2020, 12, 337–342. [Google Scholar] [CrossRef] [PubMed]
  8. Li, P.; Wu, J. Sustainable Living with Risks: Meeting the Challenges. Human. Ecol. Risk Assess. Int. J. 2019, 25, 1–10. [Google Scholar] [CrossRef]
  9. Ugochukwu, U.C.; Ochonogor, A. Groundwater Contamination by Polycyclic Aromatic Hydrocarbon Due to Diesel Spill from a Telecom Base Station in a Nigerian City: Assessment of Human Health Risk Exposure. Environ. Monit. Assess. 2018, 190, 249. [Google Scholar] [CrossRef] [PubMed]
  10. Marić, N.; Štrbački, J.; Mrazovac Kurilić, S.; Beškoski, V.P.; Nikić, Z.; Ignjatović, S.; Malbašić, J. Hydrochemistry of Groundwater Contaminated by Petroleum Hydrocarbons: The Impact of Biodegradation (Vitanovac, Serbia). Environ. Geochem. Health 2020, 42, 1921–1935. [Google Scholar] [CrossRef]
  11. Nivetha, C.; Deepika, T.; Arjunan, A.; Sivalingam, P.; Revathi, N.; Muthuselvam, M. Antimicrobial and Antioxidant Activities of Streptomyces Sps Isolated from Muthupettai Mangrove Soil. J. Pharm. Res. Int. 2021, 33, 210–234. [Google Scholar] [CrossRef]
  12. Li, P.; Karunanidhi, D.; Subramani, T.; Srinivasamoorthy, K. Sources and Consequences of Groundwater Contamination. Arch. Environ. Contam. Toxicol. 2021, 80, 1–10. [Google Scholar] [CrossRef] [PubMed]
  13. Monteiro da Fonseca, E.; Machado Publio, M.C.; de Freitas Delgado, J. Segurança Hídrica. Sist. Gestão 2023, 18, 2. [Google Scholar] [CrossRef]
  14. Basu, A.; Saha, D.; Saha, R.; Ghosh, T.; Saha, B. A Review on Sources, Toxicity and Remediation Technologies for Removing Arsenic from Drinking Water. Res. Chem. Intermed. 2014, 40, 447–485. [Google Scholar] [CrossRef]
  15. Pandey, H.K.; Duggal, S.K.; Jamatia, A. Fluoride Contamination of Groundwater and It’s Hydrogeological Evolution in District Sonbhadra (U.P.) India. Proc. Natl. Acad. Sci. India Sect. A Phys. Sci. 2016, 86, 81–93. [Google Scholar] [CrossRef]
  16. Subba Rao, N.; Ravindra, B.; Wu, J. Geochemical and Health Risk Evaluation of Fluoride Rich Groundwater in Sattenapalle Region, Guntur District, Andhra Pradesh, India. Human. Ecol. Risk Assess. Int. J. 2020, 26, 2316–2348. [Google Scholar] [CrossRef]
  17. Clement, M.; Meunie, A. Is Inequality Harmful for the Environment? An Empirical Analysis Applied to Developing and Transition Countries. Rev. Soc. Econ. 2010, 68, 413–445. [Google Scholar] [CrossRef]
  18. Hayashi, A.; Akimoto, K.; Tomoda, T.; Kii, M. Global Evaluation of the Effects of Agriculture and Water Management Adaptations on the Water-Stressed Population. Mitig. Adapt. Strateg. Glob. Change 2013, 18, 591–618. [Google Scholar] [CrossRef]
  19. Lam, S.; Nguyen-Viet, H.; Tuyet-Hanh, T.T.; Nguyen-Mai, H.; Harper, S. Evidence for Public Health Risks of Wastewater and Excreta Management Practices in Southeast Asia: A Scoping Review. Int. J. Environ. Res. Public Health 2015, 12, 12863–12885. [Google Scholar] [CrossRef]
  20. Bertrand, G.; Hirata, R.; Pauwels, H.; Cary, L.; Petelet-Giraud, E.; Chatton, E.; Aquilina, L.; Labasque, T.; Martins, V.; Montenegro, S.; et al. Groundwater Contamination in Coastal Urban Areas: Anthropogenic Pressure and Natural Attenuation Processes. Example of Recife (PE State, NE Brazil). J. Contam. Hydrol. 2016, 192, 165–180. [Google Scholar] [CrossRef]
  21. Gomes, O.V.O.; Marques, E.D.; Kütter, V.T.; Aires, J.R.; Travi, Y.; Silva-Filho, E.V. Origin of Salinity and Hydrogeochemical Features of Porous Aquifers from Northeastern Guanabara Bay, Rio de Janeiro, SE, Brazil. J. Hydrol. Reg. Stud. 2019, 22, 100601. [Google Scholar] [CrossRef]
  22. Nicolodi, J.L.; Pettermann, R.M. Vulnerability of the Brazilian Coastal Zone in Its Environmental, Social, and Technological Aspects. J. Coast. Res. 2011, 64, 1372–1379. [Google Scholar]
  23. Filgueira, J.M.; Pereira Júnior, A.O.; de Araújo, R.S.B.; da Silva, N.F. Economic and Social Impacts of the Oil Industry on the Brazilian Onshore. Energies 2020, 13, 1922. [Google Scholar] [CrossRef]
  24. Da Silva, A.L.C.; da Silva, M.A.M.; Gambôa, L.A.P.; Rodrigues, A.R. Sedimentary Architecture and Depositional Evolution of the Quaternary Coastal Plain of Maricá, Rio de Janeiro, Brazil. Braz. J. Geol. 2014, 44, 191–206. [Google Scholar] [CrossRef]
  25. Cruz, A.; da Silva, G.C., Jr.; de Almeida, G.M. Modelagem Hidrogeoquímica Do Aquífero Freático Da Restinga de Piratininga, Niterói-RJ. In XIV Congresso Brasileiro de Águas Subterrâneas; ABAS: Curitiba, Brazil, 2006; pp. 1–19. [Google Scholar]
  26. GB/T 14848-2017; Standard for Groundwater Quality. Standardization Administration of the PRC: Beijing, China, 2017.
  27. Van Hall, C.E.; Safranko, J.; Stenger, V.A. Rapid Combustion Method for the Determination of Organic Substances in Aqueous Solutions. Anal. Chem. 1963, 35, 315–319. [Google Scholar] [CrossRef]
  28. Sharp, J.H.; Peltzer, E.T.; Alperin, M.J.; Cauwet, G.; Farrington, J.W.; Fry, B.; Karl, D.M.; Martin, J.H.; Spitzy, A.; Tugrul, S.; et al. Procedures Subgroup Report. Mar. Chem. 1993, 41, 37–49. [Google Scholar] [CrossRef]
  29. EPA. Method 1603: Escherichia Coli (E. Coli) in Water by Membrane Filtration Using Modified Membrane-Thermotolerant Escherichia Coli Agar (Modified MTEC); EPA: Washington, DC, USA, 2014. [Google Scholar]
  30. Srivastav, A.L.; Ranjan, M. Inorganic Water Pollutants. In Inorganic Pollutants in Water; Elsevier: Amsterdam, The Netherlands, 2020; pp. 1–15. [Google Scholar] [CrossRef]
  31. Block, S.S. Desinfection, Sterilization, and Preservation, 5th ed.; Lippincot Willians & Wilkins: Philadelphia, PA, USA, 2001. [Google Scholar]
  32. Puri, A.; Kumar, M. A Review of Permissible Limits of Drinking Water. Indian. J. Occup. Environ. Med. 2012, 16, 40–44. [Google Scholar] [CrossRef]
  33. Banks, D. An Introduction to Thermogeology: Ground Source Heating and Cooling, 2nd ed.; John Wiley & Sons, Ltd: Oxford, UK, 2008. [Google Scholar]
  34. Bonte, M.; Stuyfzand, P.J.; Hulsmann, A.; Van Beelen, P. Underground Thermal Energy Storage: Environmental Risks and Policy Developments in the Netherlands and European Union. Ecol. Soc. 2011, 16, 1–22. [Google Scholar] [CrossRef]
  35. Griffioen, J.; Appelo, A.J. Nature and Extent of Carbonate Precipitation during Aquifer Thermal Energy Storage. Appl. Geochem. 1993, 8, 161–176. [Google Scholar] [CrossRef]
  36. Bonte, M.; Van Breukelen, B.M.; Stuyfzand, P.J. Environmental Impacts of Aquifer Thermal Energy Storage Investigated by Field and Laboratory Experiments. J. Water Clim. Change 2013, 4, 77–89. [Google Scholar] [CrossRef]
  37. Bonte, M.; van Breukelen, B.M.; Stuyfzand, P.J. Temperature-Induced Impacts on Groundwater Quality and Arsenic Mobility in Anoxic Aquifer Sediments Used for Both Drinking Water and Shallow Geothermal Energy Production. Water Res. 2013, 47, 5088–5100. [Google Scholar] [CrossRef]
  38. Bonte, M.; Röling, W.F.M.; Zaura, E.; van der Wielen, P.W.J.J.; Stuyfzand, P.J.; van Breukelen, B.M. Impacts of Shallow Geothermal Energy Production on Redox Processes and Microbial Communities. Environ. Sci. Technol. 2013, 47, 14476–14484. [Google Scholar] [CrossRef] [PubMed]
  39. Jesußek, A.; Köber, R.; Grandel, S.; Dahmke, A. Aquifer Heat Storage: Sulphate Reduction with Acetate at Increased Temperatures. Environ. Earth Sci. 2013, 69, 1763–1771. [Google Scholar] [CrossRef]
  40. Fraser, D.W.; Tsai, T.R.; Orenstein, W.; Parkin, W.E.; Beecham, H.J.; Sharrar, R.G.; Harris, J.; Mallison, G.F.; Martin, S.M.; McDade, J.E.; et al. Legionnaires’ Disease. N. Engl. J. Med. 1977, 297, 1189–1197. [Google Scholar] [CrossRef] [PubMed]
  41. Shands, K.N. Potable Water as a Source of Legionnaires’ Disease. JAMA J. Am. Med. Assoc. 1985, 253, 1412. [Google Scholar] [CrossRef]
  42. WHO. WHO Housing and Health Guidelines; WHO: Geneva, Switzerland, 2018. [Google Scholar]
  43. Weiner, E.R. Applications of Environmental Aquatic Chemistry, 3rd ed.; CRC Press: Boca Raton, FL, USA, 2013. [Google Scholar]
  44. Hayton, J. Industrial Water Treatment Process Technology; Butterworth-Heinemann: Oxford, UK, 2017. [Google Scholar]
  45. Rose, S.; Long, A. Monitoring Dissolved Oxygen in Ground Water: Some Basic Considerations. Groundw. Monit. Remediat. 1988, 8, 93–97. [Google Scholar] [CrossRef]
  46. Zhang, Z.; Xiao, C.; Adeyeye, O.; Yang, W.; Liang, X. Source and Mobilization Mechanism of Iron, Manganese and Arsenic in Groundwater of Shuangliao City, Northeast China. Water 2020, 12, 534. [Google Scholar] [CrossRef]
  47. Jakobsen, R.; Postma, D. In Situ Rates of Sulfate Reduction in an Aquifer (Romo Denmark) and Implications for the Reactivity of Organic Matter. Geology 1994, 22, 1103–1106. [Google Scholar] [CrossRef]
  48. Harvey, R.W.; Barber, L.B. Associations of Free-Living Bacteria and Dissolved Organic Compounds in a Plume of Contaminated Groundwater. J. Contam. Hydrol. 1992, 9, 91–103. [Google Scholar] [CrossRef]
  49. Judd, K.E.; Crump, B.C.; Kling, G.W. Variation in Dissolved Organic Matter Controls Bacterial Production and Community Composition. Ecology 2006, 87, 2068–2079. [Google Scholar] [CrossRef]
  50. Romera-Castillo, C.; Pinto, M.; Langer, T.M.; Álvarez-Salgado, X.A.; Herndl, G.J. Dissolved Organic Carbon Leaching from Plastics Stimulates Microbial Activity in the Ocean. Nat. Commun. 2018, 9, 1430. [Google Scholar] [CrossRef]
  51. Richards, L.A.; Lapworth, D.J.; Magnone, D.; Gooddy, D.C.; Chambers, L.; Williams, P.J.; van Dongen, B.E.; Polya, D.A. Dissolved Organic Matter Tracers Reveal Contrasting Characteristics across High Arsenic Aquifers in Cambodia: A Fluorescence Spectroscopy Study. Geosci. Front. 2019, 10, 1653–1667. [Google Scholar] [CrossRef]
  52. Baker, M.A.; Valett, H.M.; Dahm, C.N. Organic Carbon Supply and Metabolism in a Shallow Groundwater Ecosystem. Ecology 2000, 81, 3133–3148. [Google Scholar] [CrossRef]
  53. Shen, Y.; Chapelle, F.H.; Strom, E.W.; Benner, R. Origins and Bioavailability of Dissolved Organic Matter in Groundwater. Biogeochemistry 2015, 122, 61–78. [Google Scholar] [CrossRef]
  54. Longnecker, K.; Kujawinski, E.B. Composition of Dissolved Organic Matter in Groundwater. Geochim. Cosmochim. Acta 2011, 75, 2752–2761. [Google Scholar] [CrossRef]
  55. Batiot-Guilhe, C.; Emblanch, C.; Blavoux, B. Total Organic Carbon (TOC) and Magnésium: Two Complementary Tracers of Residence Time in Karstic Systems. C. R. Geosci. 2003, 335, 205–214. [Google Scholar]
  56. Barcelona, M.J. TOC Determinations in Ground Water. Ground Water 1984, 22, 18–24. [Google Scholar] [CrossRef]
  57. Pernthaler, J. Predation on Prokaryotes in the Water Column and Its Ecological Implications. Nat. Rev. Microbiol. 2005, 3, 537–546. [Google Scholar] [CrossRef]
  58. Goldscheider, N.; Hunkeler, D.; Rossi, P. Review: Microbial Biocenoses in Pristine Aquifers and an Assessment of Investigative Methods. Hydrogeol. J. 2006, 926–941. [Google Scholar] [CrossRef]
  59. Gopal, K.; Tripathy, S.S.; Bersillon, J.L.; Dubey, S.P. Chlorination Byproducts, Their Toxicodynamics and Removal from Drinking Water. J. Hazard. Mater. 2007, 140, 1–6. [Google Scholar] [CrossRef] [PubMed]
  60. Chomycia, J.C.; Hernes, P.J.; Harter, T.; Bergamaschi, B.A. Land Management Impacts on Dairy-Derived Dissolved Organic Carbon in Ground Water. J. Environ. Qual. 2008, 37, 333–343. [Google Scholar] [CrossRef]
  61. Rajendran, A.; Shimizu, G.K.H.; Woo, T.K. The Challenge of Water Competition in Physical Adsorption of CO2 by Porous Solids for Carbon Capture Applications—A Short Perspective. Adv. Mater. 2023. [Google Scholar] [CrossRef] [PubMed]
  62. Gruau, G.; Dia, A.; Olivié-Lauquet, G.; Davranche, M.; Pinay, G. Controls on the Distribution of Rare Earth Elements in Shallow Groundwaters. Water Res. 2004, 38, 3576–3586. [Google Scholar] [CrossRef] [PubMed]
  63. Makehelwala, M.; Wei, Y.; Weragoda, S.K.; Weerasooriya, R.; Zheng, L. Characterization of Dissolved Organic Carbon in Shallow Groundwater of Chronic Kidney Disease Affected Regions in Sri Lanka. Sci. Total Environ. 2019, 660, 865–875. [Google Scholar] [CrossRef]
  64. Ahmed, A.U.; Hoddinott, J.F.; Md Shaiful Islam, K.; Mahbubur Rahman Khan, A.; Abedin, N.; Hossain, N.Z.; Ghostlaw, J.; Parvin, A.; Quabili, W.; Tahsin Rahaman, S.; et al. Impacts of Bt Brinjal (Eggplant) Impacts In Bangladesh; International Food Policy Research Institute: Washington, DC, USA, 2019. [Google Scholar]
  65. McDonough, L.K.; Rutlidge, H.; O’Carroll, D.M.; Andersen, M.S.; Meredith, K.; Behnke, M.I.; Spencer, R.G.M.; McKenna, A.M.; Marjo, C.E.; Oudone, P.; et al. Characterisation of Shallow Groundwater Dissolved Organic Matter in Aeolian, Alluvial and Fractured Rock Aquifers. Geochim. Cosmochim. Acta 2020, 273, 163–176. [Google Scholar] [CrossRef]
  66. Anawar, H.M.; Akai, J.; Komaki, K.; Terao, H.; Yoshioka, T.; Ishizuka, T.; Safiullah, S.; Kato, K. Geochemical Occurrence of Arsenic in Groundwater of Bangladesh: Sources and Mobilization Processes. J. Geochem. Explor. 2003, 77, 109–131. [Google Scholar] [CrossRef]
  67. McDonough, L.K.; Andersen, M.S.; Behnke, M.I.; Rutlidge, H.; Oudone, P.; Meredith, K.; O’Carroll, D.M.; Santos, I.R.; Marjo, C.E.; Spencer, R.G.M.; et al. A New Conceptual Framework for the Transformation of Groundwater Dissolved Organic Matter. Nat. Commun. 2022, 13, 1–11. [Google Scholar] [CrossRef]
  68. MacDonald, A.M.; Dochartaigh, B.É.Ó.; Kinniburgh, D.G.; Darling, W.G. Baseline Scotland: Groundwater Chemistry of Southern Scotland; British Geological Survey: Nottingham, UK, 2008. [Google Scholar]
  69. Edwards, A.M.C.; Thornes, J.B. Annual Cycle in River Water Quality: A Time Series Approach. Water Resour. Res. 1973, 9, 1286–1295. [Google Scholar] [CrossRef]
  70. Cun, C.; Vilagines, R. Time Series Analysis on Chlorides, Nitrates, Ammonium and Dissolved Oxygen Concentrations in the Seine River near Paris. Sci. Total Environ. 1997, 208, 59–69. [Google Scholar] [CrossRef]
  71. Hunt, M.; Herron, E.; Green, L. Chlorides in Fresh Water; University of Rhode Island: Kingston, RI, USA, 2012. [Google Scholar]
  72. Hong, Y.; Zhu, Z.; Liao, W.; Yan, Z.; Feng, C.; Xu, D. Freshwater Water-Quality Criteria for Chloride and Guidance for the Revision of the Water-Quality Standard in China. Int. J. Environ. Res. Public. Health 2023, 20, 2875. [Google Scholar] [CrossRef]
  73. Chen, J.; Wu, H.; Qian, H. Groundwater Nitrate Contamination and Associated Health Risk for the Rural Communities in an Agricultural Area of Ningxia, Northwest China. Expo. Health 2016, 8, 349–359. [Google Scholar] [CrossRef]
  74. Majumdar, D. The Blue Baby Syndrome. Resonance 2003, 8, 20–30. [Google Scholar] [CrossRef]
  75. Schijven, J.F.; Imůnek, J.S. Kinetic Modeling of Virus Transport at the Field Scale. J. Contam. Hydrol. 2002, 55, 113–135. [Google Scholar] [CrossRef] [PubMed]
  76. Mahmoud, M.E.; Shoaib, S.M.A.; Salam, M.A.; Elsayed, S.M. Efficient and Fast Removal of Total and Fecal Coliform, BOD, COD and Ammonia from Raw Water by Microwave Heating Technique. Groundw. Sustain. Dev. 2022, 19, 100847. [Google Scholar] [CrossRef]
  77. Dayanti, M.P.; Fachrul, M.F.; Wijayanti, A. Escherichia Coli as Bioindicator of the Groundwater Quality in Palmerah District, West Jakarta, Indonesia. IOP Conf. Ser. Earth Environ. Sci. 2018, 106, 012081. [Google Scholar] [CrossRef]
  78. Rosen, B.H. Waterborne Pathogens in Agricultural Watersheds; NRAES: New York, NY, USA, 2000. [Google Scholar]
  79. Tyrrel, S.F.; Quinton, J.N. Overland Flow Transport of Pathogens from Agricultural Land Receiving Faecal Wastes. J. Appl. Microbiol. 2003, 94, 87–93. [Google Scholar] [CrossRef]
  80. Unc, A.; Goss, M.J. Movement Of Faecal Bacteria Through The Vadose Zone. Water Air Soil. Pollut. 2003, 149, 327–337. [Google Scholar] [CrossRef]
  81. Cotruvo, J.A.; Dufour, A.; Rees, G.; Bartram, J.; Carr, R.; Cliver, D.O.; Craun, G.F.; Fayer, R.; Gannon, V.P.J.; Dufour, A.; et al. Waterborne Zoonoses; World Health Organization: London, UK, 2004. [Google Scholar]
  82. Fong, T.-T.; Lipp, E.K. Enteric Viruses of Humans and Animals in Aquatic Environments: Health Risks, Detection, and Potential Water Quality Assessment Tools. Microbiol. Mol. Biol. Rev. 2005, 69, 357–371. [Google Scholar] [CrossRef]
Figure 1. Study site and sampling stations in the 9 pre-determined zones.
Figure 1. Study site and sampling stations in the 9 pre-determined zones.
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Figure 2. Dissolved oxygen (mg·L−1) of all nine zones. The values are shown as mean ± SD. Different letters show statistically significant differences between the zones (p < 0.05).
Figure 2. Dissolved oxygen (mg·L−1) of all nine zones. The values are shown as mean ± SD. Different letters show statistically significant differences between the zones (p < 0.05).
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Figure 3. Total organic nitrogen (mg·L−1) of all nine zones. The values are shown as mean ± SD. Different letters indicate significant statistical differences between the zones (p < 0.05). The horizontal dotted line shows the maximum limit per Brazilian legislation.
Figure 3. Total organic nitrogen (mg·L−1) of all nine zones. The values are shown as mean ± SD. Different letters indicate significant statistical differences between the zones (p < 0.05). The horizontal dotted line shows the maximum limit per Brazilian legislation.
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Figure 4. Phosphorus concentration (mg·L−1) of all nine zones. The values are shown as mean ± SD. Different letters indicate significant statistical differences between the zones (p < 0.05). The horizontal dotted line shows the maximum limit per Brazilian legislation.
Figure 4. Phosphorus concentration (mg·L−1) of all nine zones. The values are shown as mean ± SD. Different letters indicate significant statistical differences between the zones (p < 0.05). The horizontal dotted line shows the maximum limit per Brazilian legislation.
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Figure 5. Pearson correlation coefficients between total coliforms and DOC (A), TON (B), and phosphorus (C) for all nine zones. The vertical dotted line shows the maximum limit per Brazilian legislation for total coliforms (200 MPN). The horizontal dotted line shows the maximum limit per Brazilian legislation for DOC, TON, and P.
Figure 5. Pearson correlation coefficients between total coliforms and DOC (A), TON (B), and phosphorus (C) for all nine zones. The vertical dotted line shows the maximum limit per Brazilian legislation for total coliforms (200 MPN). The horizontal dotted line shows the maximum limit per Brazilian legislation for DOC, TON, and P.
Eng 04 00151 g005aEng 04 00151 g005b
Table 1. Summary of the pH values of all areas sampled.
Table 1. Summary of the pH values of all areas sampled.
ZoneMeanMinimum ValueMaximum
Brazilian Legislation LimitsN° of Points in Disagreement with Brazilian LegislationProportion of Points in Disagreement with Brazilian Legislation, %
015.925.016.886.00 to 9.000666.66
Table 2. Summary of the DOC values of all areas sampled.
Table 2. Summary of the DOC values of all areas sampled.
ZoneMeanMinimum ValueMaximum
Brazilian Legislation LimitsN° of Points in Disagreement with Brazilian LegislationProportion of Points in Disagreement with Brazilian Legislation, %
018.011.9035.3010 mg·L−10222.22
Table 3. Groundwater dissolved organic carbon obtained in different studies.
Table 3. Groundwater dissolved organic carbon obtained in different studies.
SiteReferenceMax DOC
Average DOC
Maricá, BrazilPresent study49.10<0.58.06
Puducherry, India[61]290.53.6
Petit Hermitage, France[62]--4.4
Sri Lanka[63]2.081.351.69
Anna Bay, Australia[65]
Macquarie River, Australia[67]--8.26
Bell River, Australia[67]--1.87
Elfin Crossing, Australia[67]--1.34
Silurian S, Scotland[68]3.050.45-
Table 4. Summary of the chloride values of all areas sampled.
Table 4. Summary of the chloride values of all areas sampled.
ZoneMeanMinimum ValueMaximum
Brazilian Legislation LimitsN° of Points in Disagreement with Brazilian LegislationProportion of Points in Disagreement with Brazilian Legislation, %
01170.432.0853.6250 mg·L−10111.11
Table 5. Summary of the nitrate values of all areas sampled.
Table 5. Summary of the nitrate values of all areas sampled.
ZoneMeanMinimum ValueMaximum ValueBrazilian Legislation LimitsN° of points in Disagreement with Brazilian LegislationProportion of Points in Disagreement with Brazilian Legislation, %
014.150.0016.8910 mg·L−10111.11
Table 6. Summary of the TON values of all areas.
Table 6. Summary of the TON values of all areas.
ZoneMeanMinimum ValueMaximum
Brazilian Legislation LimitsN° of Points in Disagreement with Brazilian LegislationProportion of Points in Disagreement with Brazilian Legislation, %
013.610.3013.903.7 mg·L−10333.33
Table 7. Summary of the phosphorus concentrations of all areas sampled.
Table 7. Summary of the phosphorus concentrations of all areas sampled.
ZoneMeanMinimum ValueMaximumBrazilian Legislation LimitsN° of Points in Disagreement with Brazilian LegislationProportion of Points in Disagreement with Brazilian Legislation, %
Value mg·L−10444.44
Table 8. Summary of the total coliform concentrations of all areas sampled.
Table 8. Summary of the total coliform concentrations of all areas sampled.
ZoneMeanMinimum ValueMaximumBrazilian Legislation LimitsN° of Points in Disagreement with Brazilian LegislationProportion of Points in Disagreement with Brazilian Legislation, %
0137002400200 MPN0444.44
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Publio, M.C.M.; Delgado, J.F.; Pierri, B.S.; Lima, L.d.S.; Gaylarde, C.C.; Baptista Neto, J.A.; Neves, C.V.; Fonseca, E.M. Assessment of Groundwater Contamination in the Southeastern Coast of Brazil: A Potential Threat to Human Health in Marica Municipality. Eng 2023, 4, 2640-2655.

AMA Style

Publio MCM, Delgado JF, Pierri BS, Lima LdS, Gaylarde CC, Baptista Neto JA, Neves CV, Fonseca EM. Assessment of Groundwater Contamination in the Southeastern Coast of Brazil: A Potential Threat to Human Health in Marica Municipality. Eng. 2023; 4(4):2640-2655.

Chicago/Turabian Style

Publio, Maria Cristina M., Jessica F. Delgado, Bruno S. Pierri, Leonardo da S. Lima, Christine C. Gaylarde, José Antônio Baptista Neto, Charles V. Neves, and Estefan M. Fonseca. 2023. "Assessment of Groundwater Contamination in the Southeastern Coast of Brazil: A Potential Threat to Human Health in Marica Municipality" Eng 4, no. 4: 2640-2655.

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