Ferrochrome Pollution and Its Consequences on Groundwater Ecosystems and Public Health

Abstract

Ferrochrome pollution, a by-product of the ferroalloy industry, is emerging as a significant environmental concern due to its potential to contaminate groundwater resources. This contamination occurs primarily through the leaching of heavy metals, such as chromium, into the soil and water systems. This review article presents a strategic framework for assessing environmental and health risks associated with the ferrochrome industry pollution rather than focusing on a case study. The suggested methodology is designed to guide future field investigations in areas impacted by ferrochrome industrial activities. The presence of chromium in groundwater poses serious risks to both ecosystems and human health. In aquatic ecosystems, elevated chromium levels can disrupt the balance of microbial communities, affect biodiversity, and harm aquatic organisms. For humans, long-term exposure to chromium-contaminated groundwater is associated with a range of health issues, including carcinogenic effects, skin rashes, respiratory problems, and potential damage to vital organs. The widespread use of groundwater for drinking, irrigation, and industrial purposes exacerbates the risks to public health. This paper explores the sources, pathways, and mechanisms of ferrochrome contamination, examines its impact on groundwater ecosystems, and highlights the health consequences for affected populations. Strategies for mitigating ferrochrome pollution, including treatment technologies and policy interventions, are also discussed to help safeguard both environmental and public health.

1. Introduction

Ferrochrome, an essential alloy primarily used in the production of stainless steel, plays a critical role in modern industry. It is derived by smelting chromite ore, a process that involves the use of high-temperature furnaces [1]. While ferrochrome is a valuable material in the manufacturing sector, its production is not without significant environmental consequences, particularly with regard to groundwater contamination. The smelting of chromite ores to produce ferrochrome results in the release of chromium into the environment, both in its hexavalent (Cr(VI)) and trivalent (Cr(III)) forms [2]. Chromium is a naturally occurring heavy metal found in the Earth’s crust, but the industrial activities associated with ferrochrome production have dramatically increased its concentration in the environment, especially in surrounding water systems. One of the primary concerns associated with ferrochrome pollution is its impact on groundwater, which serves as a vital source of drinking water for millions of people worldwide [3]. Groundwater contamination with chromium, particularly Cr(VI), presents a serious environmental and health risk. This form of chromium is highly toxic, mobile, and persistent in water, making it particularly dangerous for both ecosystems and human populations [4]. When chromium is released into the environment from ferrochrome plants through industrial discharges, runoff, or improper disposal of waste, it can leach into the surrounding soil and infiltrate groundwater systems. As groundwater is a major source of potable water, its contamination has far-reaching consequences [5]. Regions that rely on groundwater for drinking, agriculture, and industry are at the highest risk, especially when pollution goes unchecked. Over time, chromium contamination can result in the degradation of water quality, making it unsafe for consumption and disrupting local ecosystems [6]. The impact of ferrochrome pollutants on groundwater ecosystems is profound. Aquatic ecosystems are highly sensitive to changes in water chemistry, and the introduction of toxic substances such as chromium can disrupt ecological balance [7]. In freshwater bodies, elevated levels of chromium can reduce biodiversity, as species sensitive to the metal either die off or migrate [8]. This results in the loss of vital functions provided by these organisms, such as nutrient cycling and food chain stability. The contamination of aquatic habitats, including rivers, lakes, and wetlands, further disrupts the food chain, affecting everything from microorganisms to larger aquatic species, and even terrestrial animals that rely on these ecosystems [9]. Additionally, chromium toxicity can impact the reproductive health and survival of aquatic organisms, leading to cascading ecological effects. This contamination, in turn, can damage the sustainability of ecosystems that rely on clean water sources. Moreover, the effects of ferrochrome pollution on groundwater can extend to soil health and agricultural productivity [10]. Chromate contamination in groundwater, if used for irrigation, can lead to the uptake of chromium by plants, which, over time, may accumulate in the food chain. Crops grown in contaminated soil may accumulate toxic levels of chromium, which can be harmful to human health when consumed [11]. In addition to soil contamination, the presence of chromium in groundwater can affect plant growth and yield. Chromium disrupts normal plant physiological processes by interfering with the absorption of essential nutrients, leading to stunted growth, chlorosis, and even plant death in extreme cases [12]. As groundwater is often used in agricultural practices, contamination can lead to reduced crop production, negatively impacting the economy and food security of affected regions. The public health risks associated with chromium-contaminated groundwater are even more concerning [13]. Chromium, especially in its hexavalent form, is a known carcinogen and is linked to various other health problems. Long-term exposure to chromium-contaminated water, either through direct consumption or contact, can lead to severe health effects, including skin rashes, ulcers, and respiratory problems [14]. Studies have shown that prolonged exposure to Cr(VI) can cause cancer, particularly of the lungs, liver, and kidney, due to its ability to accumulate in the body and damage cellular DNA. Additionally, chromium exposure can lead to other chronic conditions, such as liver damage, kidney failure, and neurological disorders [15]. Populations in areas where groundwater is contaminated by ferrochrome pollutants are at a higher risk of these health conditions, particularly those who rely on untreated or inadequately treated water sources for daily consumption [16]. Vulnerable groups such as children, pregnant women, and the elderly are at an even greater risk, as they are more susceptible to the toxic effects of chromium. As the global population continues to grow and industrialization increases, the demand for ferrochrome and other materials will likely continue to rise, increasing the risk of pollution from the ferrochrome industry [17]. The widespread use of groundwater for drinking, irrigation, and industrial processes exacerbates the potential for contamination, as chromium in groundwater may travel vast distances from its point of origin. In some cases, contamination may even spread beyond the immediate vicinity of ferrochrome plants, affecting entire communities and regions [18]. Groundwater contamination, especially with heavy metals like chromium, is a slow but insidious process, as the pollutants can remain in the environment for decades, or even centuries, without natural degradation. This persistence makes the problem even more difficult to address, as once groundwater becomes contaminated, it often requires extensive and costly remediation efforts [19]. The issue of ferrochrome pollution is further complicated by the fact that the industrial sector frequently lacks proper waste disposal and treatment mechanisms. In many cases, ferrochrome plants discharge their effluents directly into water bodies or improperly dispose of solid waste, allowing pollutants to seep into the soil and enter the groundwater supply [20]. This lack of effective waste management and regulation is often compounded by insufficient monitoring and enforcement of environmental standards, which allows the problem to worsen over time. The lack of awareness among communities and the general public regarding the risks associated with chromium pollution only adds to the challenge of addressing the issue [21]. Effective environmental policies and regulations, along with better waste management practices and advanced water treatment technologies, are crucial for preventing further contamination and mitigating the damage caused by ferrochrome pollution. Groundwater is harder to monitor and remediate due to its slow movement through soil and rock. Proper industrial waste management is more critical in groundwater systems because cleanup is costly and time-consuming. So, the aim of the present study is to identify key contaminants, select appropriate sampling locations, and evaluate relevant health risks in areas impacted by ferrochrome industrial activities.

1.1. Ferrochrome Pollution and Groundwater Contamination

Groundwater serves as a critical source of drinking water for millions of people worldwide, especially in arid and semi-arid regions. However, the contamination of groundwater with chromium from ferrochrome production poses serious risks to both human health and local ecosystems [22]. Chromium can enter groundwater systems through industrial effluents, leachates from waste disposal sites, and runoff from ferrochrome production facilities. The presence of hexavalent chromium in groundwater is particularly concerning due to its toxicity and mobility [23]. Cr(VI) is highly soluble in water, making it more likely to migrate through the soil and into groundwater systems. Long-term exposure to chromium-contaminated groundwater can lead to serious health issues [24]. Drinking water contaminated with Cr(VI) has been associated with an increased risk of cancer, particularly lung, liver, and kidney cancer, as well as respiratory problems, skin lesions, and neurological disorders (Figure 1). Additionally, chromium contamination can affect soil quality, harming agricultural productivity and food safety when crops irrigated with polluted water absorb toxic levels of chromium [25]. The persistence of chromium in groundwater, combined with the difficulty of remediation, makes ferrochrome pollution particularly challenging to address [26].

1.2. Impact on Surface Water

Surface water bodies such as rivers, lakes, and reservoirs are also at risk from ferrochrome pollution. Chromium from ferrochrome production can enter surface water through direct discharge of industrial effluents, runoff from contaminated soil, or seepage from groundwater [27]. Once chromium enters surface water, it can have detrimental effects on aquatic life, including fish, amphibians, and invertebrates. Chromium in its hexavalent form is highly toxic to aquatic organisms, interfering with their metabolic processes, impairing reproduction, and causing organ damage [28]. The toxicity of chromium to aquatic ecosystems depends on several factors, including the concentration of the pollutant, the species involved, and the water’s pH and temperature. Chronic exposure to chromium can lead to the reduction of biodiversity in affected water bodies, as species that cannot tolerate the contamination may perish or migrate [29]. Additionally, the disruption of the food web caused by chromium toxicity can have cascading effects on the entire ecosystem, potentially harming both aquatic and terrestrial organisms that rely on these ecosystems for food. Moreover, the contamination of surface water may also affect the quality of recreational waters, impacting tourism and community well-being [30].

1.3. Effects on Marine Coastal Ecosystems

The impact of ferrochrome pollution on marine coastal ecosystems is another area of growing concern. Coastal zones, which often serve as critical habitats for a variety of marine species, are particularly vulnerable to pollution due to their proximity to industrial activities and discharge points [31]. Chromium can enter coastal waters through industrial discharges from ferrochrome plants located near the coastline, runoff from land-based pollution, and groundwater seepage. In marine environments, chromium can accumulate in sediments, where it may remain for long periods, potentially affecting benthic organisms that live in the sediment [32]. Marine organisms such as fish, mollusks, and crustaceans may absorb chromium through the water or by ingesting contaminated food, leading to bioaccumulation and biomagnification of chromium along the food chain. Bioaccumulation of chromium can result in toxic effects on marine species, including altered growth rates, reproductive failure, and increased susceptibility to disease [33]. The degradation of marine ecosystems due to chromium contamination not only threatens biodiversity but also impacts the livelihoods of coastal communities dependent on fishing and tourism [34].

1.4. Public Health Implications

The public health implications of ferrochrome pollution are far-reaching, with the potential to affect large populations, particularly those relying on contaminated water sources for drinking, irrigation, and daily activities. The toxic effects of chromium, especially in its hexavalent form, on human health are well-documented. Chronic exposure to chromium through drinking water, inhalation of airborne particles, or skin contact can lead to various health problems [35]. The most serious health risk associated with chromium exposure is cancer, particularly lung, liver, and kidney cancer, as Cr(VI) is a recognized human carcinogen. In addition to cancer, exposure to chromium can result in a variety of non-cancerous health issues, including skin rashes, ulcers, gastrointestinal problems, respiratory distress, and damage to the liver and kidneys [36]. Vulnerable groups, such as children, pregnant women, and the elderly, are particularly at risk, as their bodies are more sensitive to the toxic effects of chromium. Communities living near ferrochrome production facilities or in areas with contaminated water sources are at the highest risk, particularly when water treatment systems are inadequate or non-existent [37]. The long-term health impacts of chromium exposure can place a significant burden on healthcare systems, especially in low-resource settings where access to medical care and safe water is limited. Addressing ferrochrome pollution and its health impacts requires not only effective pollution control measures but also public health interventions, including water quality monitoring, early detection of health problems, and public awareness campaigns about the risks associated with chromium contamination [38].

1.5. Mitigation Strategies

Addressing the environmental and public health consequences of ferrochrome pollution requires a combination of technological, regulatory, and community-based approaches. Several methods can be used to treat chromium-contaminated water, including chemical reduction, ion exchange, and filtration technologies [39]. Phytoremediation, the use of plants to absorb and detoxify chromium, has also shown promise in reducing chromium concentrations in contaminated environments. Additionally, advanced techniques such as electrokinetic remediation and bioremediation offer potential solutions for remediating chromium-contaminated soil and groundwater [40]. Regulatory measures are crucial for controlling ferrochrome pollution. Governments must enforce stringent environmental standards, including limits on chromium discharges from ferrochrome plants and regular monitoring of water quality [41]. Waste disposal practices must be improved to prevent the leakage of chromium into surrounding environments. Furthermore, greater transparency in reporting pollution levels and the involvement of local communities in monitoring and decision-making can help ensure that environmental and public health risks are effectively addressed [42].

2. Materials and Methods

A well-designed search query is prepared for data collection. Different keywords like ferrochrome pollution, groundwater contamination, toxicity, public health, surface water, and groundwater are selected for data searching. After performing the initial search, inclusion and exclusion criteria are defined to ensure that only relevant studies are included [43]. Keyword co-occurrence analysis examines the frequency and relationships between keywords in the publications.

2.1. Suggested Methodology

To study the effects of ferrochrome pollution on groundwater, surface water, marine coastal ecosystems, and public health, a comprehensive methodology involving both field-based and laboratory-based techniques, as well as data analysis, is essential. The following methodology outlines the key steps to assess contamination, its sources, and its impacts, and to propose strategies for mitigation [44]. The first step in the methodology is selecting representative study sites where ferrochrome production activities are taking place or have historically occurred. These sites should include areas with ferrochrome production plants, local communities that rely on surface water or groundwater for drinking and agriculture, and nearby rivers, lakes, or coastal ecosystems that could be impacted by pollution [45]. The selected sites must be representative of different geographic locations, such as urban and rural settings, to understand the full range of potential impacts. A comprehensive description of study areas affected by ferrochrome industrial activities is also essential to accurately detect the contaminants. So, proper climatic data are required to understand the seasonal increasing temperature and climate change activities. These data provide a valuable reference framework for researchers to compare the industrial zone and nearby sensitive protected areas.

2.1.1. Surface, Ground, and Marine Water Sampling

Surface water samples should be collected from various locations near ferrochrome production sites, such as rivers, lakes, ponds, or reservoirs, especially locations near industrial discharge points. Sampling should occur at multiple time points over the course of a year to capture seasonal variations in pollution levels, such as after heavy rainfall or during industrial activities [46]. Different parameters like Chromium concentration, pH level, turbidity, heavy metal, organic contaminants, BOD, COD, TDS, temperature, salinity, microbial contamination, and dissolved oxygen content should be used for characterisation. Groundwater samples should be collected from wells, boreholes, and springs near ferrochrome plants, agricultural areas, and residential zones [47]. These samples should be taken periodically and from different depths to evaluate the movement and distribution of contaminants in the aquifer. For marine coastal ecosystems, water, sediment, and marine organism samples should be taken along coastal zones near ferrochrome discharge points. Sediment sampling can help evaluate the accumulation of contaminants like chromium in benthic habitats [48]. Different parameters to be measured are chromium concentrations in water and sediments, bioaccumulation of chromium in marine species (e.g., fish, mollusks, crabs), marine biodiversity (species composition and diversity), contaminant levels in marine organisms (fish tissues, shellfish, and other biota), water quality indicators such as dissolved oxygen, salinity, and turbidity, and the presence of other pollutants such as polycyclic aromatic hydrocarbons (PAHs) and heavy metals [49].

2.1.2. Public Health Data Collection

Public health data should be gathered from local health departments and community surveys that focus on incidence of chromium-related diseases (e.g., cancer, respiratory issues, skin disorders), rates of hospitalization or medical treatments related to waterborne diseases, and surveys on the use of local water sources and any health complaints from the population [50]. Additionally, surveys should be conducted to assess the general public’s awareness of water contamination risks and preventive measures. To evaluate the potential health risks associated with groundwater contamination, this review recommends following guidelines from the U.S. EPA, WHO, ATSDR, ECHA, CESI, CDC, and EFSA.

2.1.3. Laboratory Analysis

All water and sediment samples should be analyzed in accredited laboratories using standardized methods for the determination of contaminants. For chromium analysis, UV-Vis spectroscopy, Atomic absorption spectroscopy (AAS), or inductively coupled plasma mass spectrometry (ICP-MS) can be used for precise measurement of Cr(VI) and Cr(III) concentrations [51]. For heavy metal analysis, AAS, ICP-MS, or X-ray fluorescence (XRF) can be used to measure other heavy metals in water, sediment, and biota. For microbial contamination, coliform tests and polymerase chain reaction (PCR) assays can help detect pathogenic bacteria in water samples. Marine organisms’ tissues can be analyzed for chromium concentrations using techniques like mass spectrometry or AAS [52]. Macroinvertebrate and fish populations in surface water can be analyzed using species count methods, biodiversity indices (e.g., Shannon–Wiener index), and assessment of fish health (e.g., gonadal and liver conditions). Once the samples are collected and analyzed, the next step involves data analysis. Basic statistics (mean, median, and standard deviation) are used to evaluate the concentration of pollutants in water, sediment, and biota samples [53]. Analyze temporal changes in contamination levels to identify potential seasonal or industrial activity-related fluctuations in pollution. Compare pollution levels across different locations (e.g., upstream vs. downstream, industrial vs. non-industrial areas) to identify the extent of contamination. Use the data to assess potential risks to human health and ecosystems by comparing observed contaminant levels with environmental standards or health thresholds (e.g., drinking water guidelines for chromium or bioaccumulation limits) [54]. Correlate environmental data with public health data to establish links between water contamination and the prevalence of health issues in the population.

2.1.4. Ecological Impact Assessment

Using biodiversity and bioaccumulation data, the ecological impact of ferrochrome pollution can be assessed. This includes evaluating species diversity and the health of aquatic organisms (e.g., fish, invertebrates, and marine life) to determine ecosystem health [55]; identifying the presence of chromium in the food web and evaluating the potential for biomagnification in aquatic species; and assessing the impact of contaminants on water quality indicators (e.g., dissolved oxygen, turbidity, BOD) [56].

2.1.5. Health Impact Assessment

Identifying correlations between exposure to contaminated water sources and the incidence of specific diseases, such as cancers, respiratory disorders, and skin diseases. Estimating the long-term health risks associated with continued exposure to chromium in drinking water and other local water sources. Examining whether populations living near ferrochrome plants are at a higher risk of health problems compared to those living in non-polluted areas [57].

2.1.6. Policy Recommendations

Based on the findings of the contamination levels, ecological impacts, and health risks, the study will develop mitigation strategies and policy recommendations to address ferrochrome pollution. This includes advising on improvements in wastewater treatment technologies to remove chromium and other heavy metals from industrial effluents [58]; recommending regular monitoring of both surface and groundwater to detect contamination early and ensure safe water for communities; proposing public health programs, including awareness campaigns about the risks of chromium exposure and the importance of water purification; advocating for stricter environmental regulations, such as limits on chromium discharges from ferrochrome plants and mandatory reporting of pollution levels [59]; and engaging local communities in monitoring and decision-making to enhance local environmental stewardship and mitigate contamination.

3. Assessment of Ferrochrome in Surface and Ground Water Contamination

3.1. Different Exposures for Surface and Groundwater Contamination

Contamination of water resources—both surface and groundwater—can have serious environmental, health, and social impacts. However, the pathways through which these water sources become contaminated and the ways in which people and ecosystems are exposed to the contaminants can vary significantly between surface and groundwater [60]. Below, we outline the different types of exposure associated with contamination in surface and groundwater sources. Contaminants, including chemicals and heavy metals like chromium (from ferrochrome production), are often discharged directly into rivers, lakes, or other surface water bodies [61]. People and animals who come into direct contact with the contaminated water (through activities like swimming, fishing, or recreational activities) may be exposed to harmful substances. Fertilizers, pesticides, and heavy metals can wash into rivers or lakes during rainfall or irrigation, creating exposure for nearby populations who rely on these water bodies for drinking or recreational use. Improperly treated wastewater from industries, sewage plants, and households can discharge pollutants into surface water, impacting water quality [62]. Contaminants like bacteria, heavy metals, and organic compounds can increase risks to public health. People who rely on surface water for drinking, cooking, or cleaning are directly exposed to pollutants. Contaminated water can contain harmful pathogens, chemicals, or heavy metals like chromium or lead, which can cause long-term health issues such as gastrointestinal illnesses, neurological damage, and cancer (

Table 1. Chemical constituents and various effects of compounds of ferrochrome dust [66].

Compounds	Percentage	Hazardous Effect
Mg	18.1	Respiratory depression, magnesium poisoning, cardiac arrest, gastrointestinal issues, bone health disruption
Cr	14.5	Respiratory depression, skin irritation and ulcers, reproductive and developmental toxicity, allergies
Si	11.5	Lung cancer, silicosis, respiratory problems, eye irritation, systemic toxicity
Fe	6.1	acute poisoning, hemochromatosis, skin irritation
Al	12.8	Respiratory issues, bone diseases, cognitive impairment
Zn	1.6	Reduced immune function, skin irritation, respiratory issues
Ca	1.6	Hypercalcemia, kidney stones, cardiovascular issues, reproductive health issues
Cu	1.2	Wilson’s disease, hemolysis, skin and eye irritation
Mn	1.5	Muscle weakness and fatigue, behavioral changes, skin and eye irritation
Ni	1.2	Gastrointestinal issues
Pb	0.1	Allergies
Ti	0.5	Respiratory issues, eye irritation

). Contaminants, particularly heavy metals such as chromium, can accumulate in the tissues of aquatic organisms (like fish, shellfish, or plants) [63]. As humans consume these contaminated organisms, they may ingest the toxins, leading to exposure. Bioaccumulation of toxins in aquatic species may increase their concentration as they move up the food chain, affecting larger fish and humans who depend on them for food. People involved in recreational activities such as fishing, swimming, or boating in polluted water bodies are at risk of exposure through skin contact or accidental ingestion [64]. Similarly, workers in industries that rely on surface water (e.g., fishing industries, agriculture) may be exposed to contaminated water during their daily activities. Surface water contamination can also impact wildlife that relies on these water bodies for drinking, bathing, and feeding [65]. Birds, mammals, and aquatic animals can be exposed to toxic contaminants, leading to health problems, reproductive failures, or deaths. This, in turn, affects the balance of local ecosystems.

3.2. Agricultural Exposure

Groundwater is frequently used for irrigation. If groundwater is contaminated with harmful substances, such as heavy metals or toxic chemicals, crops grown with this water can absorb these pollutants, which can then enter the human food chain. People may be indirectly exposed to these contaminants by consuming contaminated produce or livestock that have ingested the tainted water [67]. People who use contaminated groundwater for cooking, bathing, or cleaning may be exposed to harmful chemicals or pathogens (

Table 2. Effects of ferrochrome alloy industry sewage on agricultural fields [72].

Exposure Pathway	Source	Contaminants	Impacts	Health Risk
Irrigation water	Discharge from ferrochrome industries	Chromium (Cr), heavy Metals (Ni, Pb, Cd)	Bioaccumulation in crops	Consumption of contaminated food
Soil contamination	Irrigation with polluted water	Hexavalent chromium (Cr(VI)), arsenic	Reduced soil fertility, altered pH	Dermal exposure, ingestion via crops
Groundwater infiltration	Leaching from industrial effluents	Chromium, sulfates, fluorides	Toxic accumulation in soil and water	Contaminated drinking water, kidney damage
Crop absorption	Uptake by plants	Chromium, lead, cadmium	Reduced yield, toxic residues in food	Long-term health issues
Livestock contamination	Drinking contaminated water, eating crops	Chromium, heavy metals	Health issues in livestock, bioaccumulation	Indirect exposure through milk/meat consumption

). This exposure may be more chronic, as groundwater often flows in a slow cycle, meaning that the contamination may persist for years without being detected. In some cases, the contamination of groundwater with volatile chemicals (such as solvents or pesticides) can lead to the release of harmful vapors [68]. These vapors may enter homes through wells, and individuals can be exposed by inhaling these contaminants. This is especially a concern with chemicals like volatile organic compounds (VOCs), which can contribute to respiratory issues and other health effects. Groundwater contamination often leads to long-term exposure because groundwater tends to be a slow-moving resource. Once polluted, it may take decades for the contamination to naturally dissipate or for treatment processes to address the pollution [69]. People who rely on contaminated groundwater for long periods are at risk of developing chronic health issues such as cancers, liver disease, kidney damage, or developmental disorders [70]. Groundwater that is contaminated with pollutants like chromium can eventually seep into surface water bodies when groundwater discharges into streams, rivers, or lakes. This process, known as groundwater–surface water interaction, can expose aquatic ecosystems to the contaminants, affecting water quality and aquatic life. This secondary contamination is often slow but can contribute to significant ecological harm over time [71].

3.3. Risk of Detection

Contamination in surface water is often more easily detectable due to visible changes in water quality (e.g., discoloration, odor, or the presence of dead fish). Water testing can also be performed relatively quickly [73]. Groundwater contamination is often more difficult to detect because it does not show visible signs of pollution. People may be unaware of the contamination until serious health effects are observed or routine testing reveals the presence of pollutants. Exposure often happens directly through contact (swimming, fishing, irrigation) or indirectly via the food chain (bioaccumulation in aquatic species). Exposure is usually indirect through consumption (drinking water), domestic use (bathing, cleaning), or agricultural applications (irrigation of crops) [74].

3.4. Risk of Contamination in Open Drainage

The risk of detecting pollution or hazardous substances in open drainage systems can be influenced by various factors, such as the type of contaminants, the monitoring methods in place, and the flow dynamics of the drainage system. When it comes to ferrochrome or other industrial pollutants, detecting contamination in open drainage systems presents specific challenges and risks [75]. Open drainage systems, such as ditches, canals, and natural streams, may allow contaminants to spread over a large area, making it difficult to trace or monitor pollution levels effectively. Industrial waste, including ferrochrome slag or effluents, may be diluted by rainfall or surface water runoff, further complicating detection. Once pollutants enter an open drainage system, they may be diluted by surface runoff or carried away by the natural flow of water [76]. This can lower the concentration of contaminants, making detection more difficult, especially in large or fast-moving water bodies. The flow rate in open drainage systems can vary depending on rainfall, seasonal changes, or human activities. During dry periods, water may stagnate, allowing pollutants to accumulate and concentrate. Conversely, during heavy rains, the flow can increase and dilute contaminants [77]. These variations complicate detection and make it harder to identify pollution trends over time. Some open drainage systems may run through remote or inaccessible areas, making it difficult for authorities or environmental organizations to monitor them regularly. This increases the risk of undetected pollution, as monitoring may be irregular or absent in these locations [78].

3.5. Different Detection Methods

Visual methods (e.g., spotting discoloration, foaming, or unusual odors) are sometimes used for detection, but they are often unreliable for detecting pollutants like heavy metals in low concentrations. Ferrochrome-related contamination, such as chromium, may not be visible to the naked eye, even though it is present in harmful quantities [79]. Regular water quality sampling can help detect contaminants, but it requires specialized equipment and laboratory analysis (

Table 3. Different detection methods for contaminants in water from ferrochrome alloy industry effluents [82].

Detection Methods	Target Contaminants	Advantages
Atomic absorption spectroscopy (AAS)	Chromium (Cr), lead (Pb), cadmium (Cd), nickel (Ni)	High sensitivity, quantitative analysis
Inductively coupled plasma mass spectrometry (ICP-MS)	Heavy metals (Cr, Pb, Cd, Ni, As)	Ultra-trace detection, high accuracy
UV-visible spectrophotometry	Hexavalent chromium (Cr(VI))	Simple, cost-effective for Cr(VI)
X-ray fluorescence (XRF)	Heavy metals, total chromium	Non-destructive, rapid analysis
Electrochemical methods (e.g., anodic stripping voltammetry)	Chromium, lead, cadmium	Portable, low-cost, field applications
Chromatographic methods (e.g., ICP-OES, HPLC)	Chromium species (Cr(III), Cr(VI)), organics	High specificity, accurate speciation
Biosensors	Chromium, arsenic, heavy metals	Fast, low-cost, eco-friendly

). Sampling may not always occur in the right places or at the right times, especially in larger drainage networks [80]. Modern technology allows for the installation of automated sensors and monitoring stations to detect pollutants like heavy metals or specific chemical signatures. However, these systems are often costly and may not be deployed in all open drainage systems, leaving some areas vulnerable to undetected contamination. Remote sensing technologies, such as satellite imagery or drone surveillance, can sometimes identify large-scale contamination events, but they may not be sensitive enough to detect low-level pollution or pollutants buried within soil or sediments [81].

3.6. Human Factors

In many regions, especially in developing countries or areas with limited resources, monitoring open drainage systems for pollution may not be a priority. Without regular inspections, illegal dumping of industrial waste or runoff from industrial activities may go undetected for long periods [83]. Communities and industries may not always report pollution events, especially if there is a lack of public awareness or concern. In some cases, industries may deliberately conceal contamination to avoid penalties, increasing the likelihood of undetected pollution [84]. Pollution in open drainage systems often comes from multiple sources. Ferrochrome production facilities, sewage systems, agricultural runoff, and domestic waste may all contribute to the contamination. This complexity can make it challenging to pinpoint the exact source of pollution, further increasing the difficulty of detection [85]. The maximum allowable limits for heavy metals in drinking water are established by international and national health authorities to protect public health from long-term exposure to toxic substances. According to the WHO, the guideline limits are set at 0.05 mg/L for chromium and 0.01 mg/L for arsenic and lead. However, the U.S. EPA allows up to 0.01 mg/L for chromium, arsenic, and lead. Similarly, the European Union and the Bureau of Indian Standards enforce a limit of 0.05 mg/L for chromium, arsenic, and lead, which are higher than WHO and EPA recommendations.

4. Measures and Regulations for Assessing Ferrochrome Pollution

Ferrochrome pollution, particularly through industrial effluents and waste disposal, presents significant risks to both groundwater ecosystems and public health. The discharge of toxic substances like hexavalent chromium from ferrochrome production can contaminate open drainage systems, which often serve as conduits for these pollutants. Due to the lack of containment in open drainage channels, contaminants can easily spread, making it difficult to detect pollution early [86]. These open systems are susceptible to variability in flow, with pollutants becoming diluted during heavy rains or concentrated in stagnant periods, further complicating detection and response [87]. The toxic metals, especially chromium, can infiltrate groundwater, posing severe long-term health risks such as cancer, organ damage, and developmental issues, especially to vulnerable populations like children and pregnant women. Additionally, the contamination of water sources can disrupt local ecosystems, harming biodiversity and reducing the quality of water for consumption and agricultural use. Monitoring and mitigation efforts are often hindered by limited infrastructure, accessibility issues, and insufficient regulation, which delay both the detection of pollution and effective remediation [88]. Addressing these risks requires stronger waste management practices, regular monitoring, and community engagement to ensure that contaminants are identified and removed before they cause irreversible damage to both the environment and public health. To control pollution from ferrochrome production and its impact on groundwater ecosystems and public health, a comprehensive and multi-faceted approach is essential. Ferrochrome industries must adopt better waste management strategies to minimize the release of pollutants into the environment [89]. This includes ensuring proper treatment of industrial effluents to neutralize or remove hazardous substances like chromium before they are discharged into drainage systems. Recycling and reusing waste materials, such as slag, should be prioritized to reduce the volume of toxic waste generated. Governments should implement and enforce stringent regulations regarding the disposal of industrial by-products, including chromium-containing effluents [90]. Regular monitoring of emissions and discharges from ferrochrome production facilities should be required, with penalties for non-compliance. These regulations should be designed to protect both surface water and groundwater systems. Regular water quality testing and real-time monitoring of open drainage systems should be established to quickly detect contamination [91]. This can be achieved through the installation of automated sensors, remote sensing technologies, and routine water sampling [92]. Implementing an early warning system for pollution could facilitate faster responses and prevent widespread contamination. Investment in advanced wastewater treatment technologies, such as reverse osmosis or ion exchange, can significantly reduce the levels of toxic metals in effluent before it enters drainage systems. Additionally, ferrochrome slag should be properly stored or treated to prevent the leaching of contaminants into the environment, including the use of impermeable liners or encapsulation techniques [93]. Raising awareness among local communities about the risks associated with ferrochrome pollution is essential. Public education campaigns can empower residents to report signs of contamination, such as changes in water color, odor, or wildlife behavior. Encouraging community participation in monitoring efforts can help to identify potential pollution sources and increase accountability among local industries [94]. The use of plants (phytoremediation) and microorganisms (bioremediation) to absorb and break down pollutants in contaminated soils and groundwater offers an environmentally friendly and cost-effective approach to pollution control [95]. Encouraging the use of these natural methods can help restore polluted areas over time. The ferrochrome industry should invest in cleaner, more sustainable production technologies, such as energy-efficient furnaces, to reduce emissions and waste [96]. Promoting research into alternatives to chromium in ferrochrome production could help reduce the overall environmental impact of the industry. Governments, industries, environmental NGOs, and local communities should collaborate to create a unified strategy for controlling ferrochrome pollution [97]. Sharing knowledge, resources, and best practices can help ensure that all stakeholders play an active role in protecting groundwater and public health.

5. Conclusions

Both surface water and groundwater contamination present significant exposure risks to human health, ecosystems, and wildlife. However, the pathways, timing, and persistence of these exposures differ. Surface water contamination tends to offer more immediate and detectable exposure risks but can be more easily addressed through treatment or pollution control [98]. In contrast, groundwater contamination is often more insidious, providing long-term and chronic exposure risks that can go undetected for years. Effective management of both resources requires a combination of prevention, monitoring, treatment, and public awareness to minimize exposure and ensure the safety of water resources for future generations. Ferrochrome pollution poses a serious threat to groundwater ecosystems and public health, with toxic substances like chromium contaminating both water sources and the environment [99]. The discharge of industrial waste into open drainage systems exacerbates the spread of these pollutants, making detection and remediation challenging. This pollution not only harms aquatic life but also jeopardizes the safety of drinking water for communities, leading to long-term health risks [100]. However, through the adoption of improved waste management practices, stricter regulations, enhanced monitoring systems, and the involvement of local communities, the negative impacts of ferrochrome production can be mitigated. Sustainable industrial practices and innovative environmental technologies, such as phytoremediation and bioremediation, offer promising solutions for addressing pollution at its source and restoring affected ecosystems [101]. A collaborative effort among governments, industries, and communities is crucial to ensure the protection of both the environment and public health, securing a cleaner and safer future for all.