Geochemical Insights into Environmental Studies: A Global Perspective from Western Iran

Environmental pollutions are considered a significant challenge in all human societies. Heavy metals, recognized as fundamental environmental pollutants, enter the environment through human activities and can pose various environmental hazards. In this study, a comprehensive investigation of environmental pollutions in Aligudarz County is considered as a strategic point in Iran and serves as a model for similar studies worldwide. The research utilizes geochemical, mineralogical, and statistical approaches to examine pollutions, providing innovative and quantitative insights into understanding the geochemistry of the environment and the relationship between pollutions and environmental factors. The results indicate that the study area is subject to moderate to severe pollution from toxic elements, including molybdenum, lead, cadmium, and copper. These pollutions are correlated with the geochemical, mineralogical, and environmental analysis of the region, and the information derived from this study contributes to environmental management and protection. Considering the research findings, this research model can serve as a global template for environmental studies, playing a crucial role in enhancing understanding of pollutions and advancing knowledge in this field. Therefore, the current research has a broad impact on fostering innovations and advancing knowledge in pollution management and environmental conservation.


Introduction
Environmental pollutions are recognized as one of the significant and prominent challenges in all human societies (Gueye et al., 2023).Heavy metals are considered one of the primary environmental pollutants worldwide (Chakraborty et al., 2017).In fact, heavy metals are among the pollutants with high stability and persistence that, unlike organic pollutants, do not undergo decomposition through chemical or biological processes in nature (Mohanty et al., 2023).These metals are naturally essential in small quantities for both the human body and the environment.However, at higher concentrations, primarily introduced by human activities, they pose numerous environmental hazards (Kolesnikova et al., 2023(. Aligudarz County, located in western Iran, possesses a unique geographical position that can contribute to the spread of environmental pollution to distant areas.The strategic location of this region plays a crucial role in the distribution and transmission of pollutants at the regional and even global levels (Mohajjel et al., 2003).A comprehensive and precise study of environmental pollutions in this area can be recognized as an effective and efficient global research model.In addition, this research aims to investigate environmental pollutions in the Aligudarz County area in Iran using geochemical, mineralogical, and statistical approaches.This interdisciplinary and innovative perspective on pollution analysis enables the provision of new insights and effective quantitative and qualitative results in understanding the geochemistry of the environment and the relationship between pollutants and various environmental factors.
As a result, this study not only contributes to improve the understanding of environmental pollutions in Aligudarz but also serves as a research model applicable globally.Therefore, the current research plays a significant role in advancing knowledge in the field of environmental studies and fostering innovations related to pollution management.

Geological location
The study area is located in the western part of Iran within the boundaries of Aligudarz County, with an approximate geographical position of 49 degrees and 42 minutes east longitude and 33 degrees and 24 minutes north latitude (Dehghani et al., 2022).This county, covering approximately 5,338 square kilometers and having a population of around 145,000 people, is situated in the heart of the Zagros mountain range (Zarasvandi et al., 2019).In terms of climatic characteristics, the region experiences a moderate mountainous climate with cool winters, as indicated by Karimi et al. (2016).The average precipitation in Aligudarz County is variable, ranging from 450 to 800 millimeters per year, and the elevations reach up to 2,000 meters above sea level (Akbari et al. 2023).
Aligudarz, positioned at approximately 49 degrees and 42 minutes east longitude and 33 degrees and 24 minutes north latitude, holds a strategic geographical location that has had a significant impact on the development and diversity of natural and cultural resources in the region (Heydar i et al., 2024; Porhemmat & Altafi Dadgar, 2023) (Figure 1).

Research Methodology
This study comprises two main categories of research: field studies and laboratory experiments.
Field studies began after a preliminary review, during which existing data and relevant literature were collected.Using satellite imagery, sites were identified, and subsequent field visits were conducted to gather data.In addition to documenting and studying the sedimentary and geomorphic features of the region, 110 sediment samples (mostly composed of silt, clay, and fine sand) were collected from a depth of 10-20 centimeters below the surface for grain size and geochemical analyses.Geographic coordinates were determined using the Global Positioning System (GPS).Samples were primarily collected from various locations in the floodplain, with a specific focus on the margins of seasonal and perennial water bodies, as they could transport sediment from different sources.Efforts were made to collect mostly dry samples, and naturally moist samples were dried in sunlight to prevent errors in geochemical data.For the analysis of particle size, samples with particle diameters less than 63 microns were processed using the Cilas 1064 laser granulometer wet sieving instrument.Statistical parameters such as mean, median, mode, sorting, elongation, and skewness were calculated using the Sediment Size software.The collected samples underwent analysis at the Institute of Earth Sciences, Iran, using X-ray Diffraction (XRD) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS).Mineralogical analyses were performed using the XRD-7000 X-ray diffractometer.The Perkin Elmer ELAN 6100 DRC-e Inductively Coupled Plasma Mass Spectrometr y (ICP-MS) model was employed for accurate measurement of various metallic, non-metallic, and trace elements in the samples.The standard indices have been employed to investigate environmental pollution.
One of these indices is the "Accumulation Index of Environmental Earth," calculated based on the Muller equation (1969).It is used to assess the pollution of samples with various elements.
In this equation, C n represents the concentration of measured elements, and B n is the concentration of elements in reference samples (Muller, 1969).
Moreover, the "Enrichment Factor (EF)" utilizes the equation proposed by Yongming et al (2006) to determine the concentration of elements.
In this equation, C x represents the concentration of the specific element, and R denotes the concentration of the reference element (Yongming et al., 2006).
The Pollution Load Index (Cf) is also calculated

Discussion and Analysis
The conducted studies in this research present multiple results, each of which is individually examined in the following section.

Sediment Grain Size Studies
The analysis and examination of particle size measurements play a crucial role in understanding the sedimentary environment, enabling the analysis of sediment transport factors, and consequently, identifying the origins of various sediments (Morales et al., 2019;Hernandez-Corder, 2019).The results obtained from the investigation of 110 representative samples are presented in Table 1.Grain size studies indicate that the majority of these samples have a high percentage of silt and clay (Table 1).The presence of these fine particles can play a significant role in the transport of pollutants from upstream areas towards the plain.According to Table 1, the highest percentage of sedimentary particles consists of silt and clay, constituting over 60% in the selected samples.Therefore, the average percentage of silt and clay in the studied samples is 61.59%.Additionally, after silt and clay, sand comprises the highest percentage with an average of 25.7%, followed by gravel w ith an average percentage of 13.56% (Figure 2).

Mineralogical Studies
Mineralogical studies of sediments not only

Elemental Studies
Diverse elements, including Ni, Th, La, V, Y, Co, Ta, Ce, Nb, Ti, Zr, Sc, Cs, preserve their inherent characteristics during various processes such as d ia g e n e s i s, w e at h e r i n g, a n d m e t a m o r p hi s m (Pourmorad et al., 2021;Wang et al., 2022).These elements possess the capability to retain their primary features, and this capacity can assist researchers in analyzing various geochemical data (Ahamad et al., 2021).For instance, the investigation and identification of environmental pollution are among the fundamental applications of these elements (Espejel-Garcia & Espejel-Garcia, 2022).Furthermore, the examination of diverse Earth characteristics, including tectonic and morphotectonic features, determination of the initial origin of sediments, and ancient climatic conditions, are essential features of these elements (Pourmorad & M ohanty, 2022).The results of elemental measurements (both major and trace) using the ICP Mass Spectrometer are presented in Table 3.

Figure 3
Comparative pie chart of the average percentages of different minerals in the studied samples.(Figure 4) and linear graph (Figure 5), it becomes apparent that the highest percentage belongs to copper (Cu), z inc (Zn), and manganese (M n).

Geografia
Additionally, the concentration of some highly toxic elements, such as arsenic (As) and cadmium (Cd), is less than one percent, and the lead (Pb) concentration is 6 percent Due to the significant increase in soil pollution with elements such as copper, zinc, and manganese (similar to the studied samples), this issue may pose a potential hazard (Ahamad et al    nº 49 -2024 infertility, serious neurological problems, and skeletal issues, all of which are negative outcomes of this element in the soil (Tapia-Fernandez et al., 2017).
Even at low percentages, the presence of lead can lead to various problems, including anemia, joint problems, heart issues, mental retardation, and severe headaches (Sheikh et al., 2020).

Statistical Studies
Separately, statistical methods play a crucial role in determining the nature of pollution sources from a human or natural perspective (Espejel et al., 2022).In this article, correlation analysis was employed to investigate relationships between various elements, and the results of these analyses are presented in Table 4. Based on the conducted correlation analysis, three distinct clusters, indicating potential different sources, have been identified.
These clusters include: 1. Lead, arsenic, molybdenum, 2. Nickel and cobalt, 3. Lead, zinc, and cadmium (Table 4).Statistical data are capable of delineating elemental relationships and the concentration of each element for various purposes, including pollution source identification (Gun & Park, 2020).In this study, correlation analysis was employed to determine the relationships between toxic elements in the collected samples.According to Table 4, three distinct groups with common origins are distinguishable, namely: 1. Lead, molybdenum, and arsenic 2. Lead, cadmium, and zinc

Nickel and cobalt
The results from Table 4 can play a significant role in identifying the origin or variability of these elements.It is worth mentioning that processes related to pollution and oxidation, including the absorption, mobility, and sedimentation of toxic elements, may impact the effectiveness of correlation analysis, leading to less conclusive results.

Environmental Index Studies
In this research, global standard environmental indicators were used to determine the concentration of different toxic elements in the study area.
Environmental data analysis using the Accumulation Index of Soil Pollution indicates that the studied samples exhibit moderate to severe pollution for cer tain elements (Izah, 2017).In this ar ticle, Geoaccumulation index (Igeo), Contamination factor (Cf), Nemro integrated pollution (NIP) and Enrichment factor (EF) are used (Table 5).
According to this index, some samples show moderate to severe pollution levels for elements such as molybdenum (Mo), copper (Cu), lead (Pb), and cadmium (Cd).In contrast, these samples are free of pollution or have low pollution percentages for other elements based on this index.It is noteworthy that a small percentage of samples exhibit low to moderate pollution levels for magnesium (1.3%), nickel (2.9%), and praseodymium (5.3%) (Table 5).The results obtained from the Enrichment Factor (EF) for the studied samples show similar outcomes to the Accumulation Index of Soil.According to this index, the studied samples exhibit moderate to high enrichment for elements such as molybdenum (Mo),

Conclusion
The results obtained from this study, aimed at determining the dispersion of various toxic elements using geochemical methods, have yielded multiple achievements, which will be discussed in the following section: • Grain size studies indicate that the predominant composition of these samples consists of silt and clay.These results provide valuable information that can contribute to underst an din g t h e p hy sical char ac ter istic s of Quaternary sediments and play a crucial role in the geochemical analysis of sediments.
• Mineralogical studies of the samples through Figure 1 Geographic Location (A) and Sampling Points' Positions (B) in the Study Area.
using the equation proposed byHakanson (1980)  to assess the contamination of samples with toxic elements.This index reflects the ratio of the concentration of the target element in the study samples to the concentration of the element in the reference samples.CF = [C] Sample / [C] BackgroundCadernos deGeografiaAdditionally, the Nemerow Pollution Index (NIP) is employed as a standard index to assess the contamination risk of samples with heavy elements, and it is defined by the equation proposed by Yang et al maximum value of the pollution index for each element; Cf ave : The average value of the pollution index for each element(Yang et al., 2015).
provide valuable information about the types of minerals constituting the sediments but also play a vital role in environmental analyses and the identification of pollution sources (Zhang et al. 2021).The conducted research for identifying minerals present in the studied samples (Table 2) indicates that epidote, quartz, orthoclase, and albite are the predominant minerals in these samples.Minerals such as orthoclase and albite are recognized as key minerals in the Earth's crust and can be considered

Figure 2
Figure 2Average percentage composition of sedimentary components in the studied samples.
Furthermore, in addition to the primary minerals introduced in the studied samples, significant clay minerals such as illite, kaolinite, muscovite, montmorillonite, and chlorite are also notably present (Van der Meer, 2018).These minerals are capable of adsorbing toxic elements present in the soil through cation exchange processes and surface adsorption (MalAmiri et al., 2022).In the studied samples, gypsum minerals (hydrated calcium sulfate) are also observed.The presence of these minerals in the studied samples indicates the acidification of the environment due to the oxidation of various sulfide minerals.The only carbonate mineral identified in the studied samples is calcite, which plays a crucial role in pH variations of the environment and contributes significantly to neutralization capacity and buffering (Figures 3 and 4).
Geochemical studies are conducted to achieve specific objectives such as determining the origin of sediments, assessing environmental pollution, and identifying long-term characteristics, among others (Pourmorad et al., 2022).The results of this research indicate a diverse range of concentrations for various toxic elements.Examining the extent of variations between the minimum and maximum values of elements reveals a relatively wide range of fluctuations within these minimum and maximum values.Additionally, by examining Table 3, it is evident that the coefficient of variation for these elements (comprehensive statistical community index) is greater than one, indicating potential heterogeneity in the statistical community concerning various variables (toxic elements).Furthermore, through the circular diagram

Figure 4
Figure 4Comparative pie chart of the average percentages of toxic elements in the 110 samples (%).

Figure 5
Figure 5Linear comparison chart of the average concentrations of toxic elements in the studied samples (ppm).

X•
-ray diffraction analysis have led to the identification of various minerals in primar y, secondary, and clay minerals sections.Primary minerals, including epidote, quartz, orthoclase, and albite, are noteworthy in the samples.Clay minerals encompass illite, kaolinite, muscovite, montmorillonite, and chlorite.Secondar y minerals such as alunite, barite, and jarosite are also observed in the study samples.The presence of calcite as a carbonate mineral indicates environmental diversity and varied pollution sources.Additionally, some obtained minerals, including rare ones, exhibit characteristics associated with sulfide mineralization zones.The study area exhibits moderate to severe contamination in terms of the concentrations of toxic elements such as molybdenum (Mo), lead (Pb), cadmium (Cd), and copper (Cu).Environmental data analysis using the geoaccumulation index indicates that the studied samples are contaminated with molybdenum, copper, lead, and cadmium at moderate to severe levels.According to the Enrichment Factor (EF), the samples show moderate to high enrichment for molybdenum, copper, lead, and cadmium.The Contamination Factor (Cf) suggests that the samples have significant contamination levels for molybdenum and cadmium, while showing low to moderate co nt a minatio n le vel s fo r co p p e r, lead, manganese, and praseodymium.Additionally, the Nemerow Pollution Index (NIP) indicates high pollution for molybdenum, lead, and cadmium, with moderate pollution for copper.A comprehensive analysis of the research results in the study area indicates a noticeable contamination with toxic elements such as molybdenum, lead, cadmium, and copper in the geochemical context, ranging from moderate to severe levels.These findings align with mineralogical investigations, as primary minerals like epidote, quartz, and orthoclase, as well as secondary minerals such as illite and kaolinite, have been identified as significant pollutants.The diversity in minerals may arise from various climatic conditions and the presence of diverse pollution sources.Overall, this integrated analysis of geochemistry, mineralogy, and environmental aspects highlights the extensive climatic and pollution influences on the geological composition and characteristics of the region.The information nº 49 -2024 derived from this study can contribute to proper environmental management and conservation.The research results not only provide rich information about geochemical pollutants, but also, by linking these data to mineralogical analysis, position this study as a global model.

Table 1
Granulation analysis results for some studied sediments

Table 2
The results of the study of the minerals present in the studied samples(%)

Table 3
The results of the statistical study of toxic elements in the studied samples in terms of PPM

Table 4
The results of the correlation study between the studied elements.Separated numbers indicate significant correlation between data

Table 5
The results of the evaluation of environmental indicators(Igeo, EF, Cf, NIPI)

Table 5
The results of the evaluation of environmental indicators(Igeo, EF, Cf, NIPI)