Evaluation of ecological and health risks of trace elements in soils of olive orchards and apportionment of their sources using the APCS-MLR receptor model.

Izmir, Turkey's third most populous city, is in an important position in terms of both agriculture and industry. The province, which contributes 9.3% to the country's industrial production, also has an important potential in terms of olive cultivation. However, until now, no research has been undertaken to analyze the content of trace elements (TEs) in the soil of olive orchards in Izmir. This study was carried out to determine the pollution level and ecological risks of TEs in the olive orchards soils of Izmir province, to reveal their potential sources and to evaluate their health risks. Among the TEs, the average content of only Ni (37.9 mg/kg) exceeded the world soil average content (29 mg/kg), while the average content of only Cd (0.176 mg/kg) exceeded the upper continental crust content (0.09 mg/kg). Enrichment factor revealed that there was significant enrichment for Cd in 73.6%, Ni in 11.6% and Cr in 5.4% of olive orchards, respectively, due to polluted irrigation water and agrochemicals. Similarly, ecological risk factor indicated that there were moderate and considerable ecological risks for Cd in 48.8% and 23.3% of olive orchards, respectively. Absolute principal component scores-multiple linear regression (APCS-MLR) model showed that Ni and Cr in the study area are affected by agricultural sources, Al, Co, Cu, Fe, Mn, Pb and Zn originate from lithogenic sources, and Cd originates from mixed sources. Based on health risk evaluation methods, non-carcinogenic and carcinogenic effects would not be expected for residents. This study provides significant knowledge for evaluating soil TE pollution in olive orchards and serves a model for source apportionment and human health risk evaluation of TEs in other agricultural regions.

Boron contamination and related health risk assessment in the soils collected from olive groves in Izmir province, Türkiye.

Although boron (B) is an essential element for plants, high levels are also toxic. In this respect, pollution of soils by B may pose a serious problem for ecosystem and human health. On the other hand, studies evaluating the ecological and human health risks that may arise due to B contamination in agricultural soils are limited. In this study, it was aimed to determine the B pollution degree of the soils taken from the olive groves of Izmir province, which is approximately 180 km away from the B deposits in the Bigadiç district. In addition, the factors affecting boron adsorption and availability were discussed and the ecological and health risks of boron were evaluated. For this, soil samples were collected at depths of 0-30 cm from 118 olive groves and their B, Al, Fe, pH and organic matter contents were determined. The mean B content (47.08 mg/kg) of the study area was comparable to world-soil average B concentration (42 mg/kg). Also, B had a "low potential ecological risk" in the study area according to the ecological risk index results. On the other hand, based on the results of contamination factor (Cf) and enrichment factor (EF), "moderate contamination" and "significant enrichment" were found in the study area for B. These findings indicated that the B content in the study area is mainly related to the soil parent material, but irrigation water also contributes slightly to B content. Correlation analysis results suggested that Al and Fe contents of the soils in the study area may have an effect on B adsorption. The results of health risk assessment indicated non-carcinogenic effects are not expected for adults and children exposed to soil B content by ingestion, dermal contact and inhalation.

The importance of using soil series-based geochemical background values when calculating the enrichment factor in agricultural areas.

The enrichment factor (EF) is one of the most commonly used indices for determining the source of air, water and soil pollution. However, concerns have been raised about the accuracy of the EF results because the formula leaves the choice of background value to the researcher's discretion. The EF was used in this study to assess the validity of such concerns and to determine heavy metal enrichment in five soil profiles with different parent materials (alluvial, colluvial, and quartzite). Moreover, the upper continental crust (UCC) and specific local background values (sub-horizons) were used as the geochemical backgrounds. When UCC values were applied, the soils were moderately enriched in Cr (2.59), Zn (3.54), Pb (4.50) and Ni (4.69), and significantly enriched in Cu (5.09), Cd (6.54) and As (6.64). Using the sub-horizons of the soil profiles as a background value, it was found that the soils had "moderate enrichment" by As (2.59) and "minimally enrichment" by Cu (0.86), Ni (1.01), Cd (1.11), Zn (1.23), Cr (1.30), and Pb (1.50). As a result, the UCC reported an inaccurate conclusion indicating that soils were 3.84 times more heavily polluted than they were. In addition, the statistical analyses performed in this study (Pearson correlation analysis and principal component analysis) revealed that the percentage of clay in the soil horizons and the cation exchange capacity had strong positive relationships (r ≥ 0.670, p < 0.05) with certain heavy metals (Al, Zn, Cr, Ni, Pb and Cd). These findings indicated that sampling from the "lowest horizons" or "parent materials" of the soil series would yield the most accurate results in determining the geochemical background values in agricultural areas.

Evaluation of radioactive and heavy metal pollution in agricultural soil surrounding the lignite-fired thermal power plant using pollution indices.

Soil pollution caused by heavy metals negatively affects the environment and human health. However, the assessment of the environmental and ecological risks caused by heavy metals in agricultural soils in developing countries is limited. This study was carried out to determine heavy metal pollution and its possible sources in the agricultural lands surrounding the lignite-fired Afsin-Elbistan thermal power plant (TPP). A total of 52 soil samples were collected from the agricultural soils surrounding the TPP, and seven different heavy metal (U, Th, Ni, Fe, Cu, Cr and Zn) analyzes were performed on these samples. Soil samples were taken according to the prevailing wind direction. Nickel had a higher geoaccumulation index (1.40) and enrichment factor (5.09) values than the other metals. In addition, U posed a "moderate potential ecological risk" in the study area. Pearson correlation and principal component analyses showed that U, Ni, and Cr were controlled by anthropogenic sources.

Evaluation of environmental and ecological risks caused by metals in agricultural areas: an example in the Amik Plain of South Turkey.

The works of literature evaluating the eco-environmental risks posed by metals in agricultural areas in developing countries remains limited. This study sought to evaluate the environmental and ecological risks posed by metals in the intensively cultivated areas of the Amik Plain as well as to determine the origins of the metals. For this purpose, 137 soil samples were taken from agricultural production areas of the Amik Plain, and 11 metals (Al, Fe, Ni, Pb, Co, Cr, Cu, Mn, Zn, Cd and As) were examined in the samples. As Ni had the highest average enrichment factor (EF) value (8.04) when compared with the other metals, the soils were found to be significantly enriched with Ni. The Pearson correlation analysis and principal component analysis showed that the Zn concentration was controlled by lithogenic sources, while the Ni, Pb, Cd, Cr and Cu concentrations were controlled by both anthropogenic and lithogenic sources.

The effect of different land use planning scenarios on the amount of total soil losses in the Mikail Stream Micro-Basin.

Erosion is seen as a major productivity problem in the world. Unplanned agricultural practices caused by human activities initiate the soil erosion process. Especially in sloping areas, agricultural activities without soil conservation measures accelerate this process. This study prepared land use planning (LUP) scenarios to reduce soil losses in the Mikail Stream Micro-Basin, which has an erosion problem and a rough topography. ILSEN land evaluation method, which is formed by interpreting FAO land evaluation principles according to Turkish conditions, was used in the creation of the scenarios. Soil conservation (terracing and contour agriculture) land-use types (LUT) that can help in erosion reduction were included in the ILSEN method and 8 different LUP scenarios were created. Soil protected (terracing and contour farming) LUTs that can help reduce erosion were included in the ILSEN method and 8 different LAP scenarios were created. The RUSLE Method integrated with the Geographic Information System (GIS) was used to calculate the estimated amount of soil loss caused by the scenarios created. For land evaluation and erosion studies, serial-based soil map of the area and Google Earth images were used. Scenario 7 created has reduced soil loss by 79% compared to the present land use (Scenario 8) of the basin. While the soil loss caused by the present land-use of the basin was 335.95 tons ha-1 year-1 on average, the amount of soil loss caused by the 7th scenario was calculated as 69.05 tons ha-1 year-1 on average. The results showed that the ILSEN land evaluation method can be a model to be used in the creation of erosion-reducing LUP scenarios in areas with erosion problems.

Arsenic and trace metal concentrations in different vegetable types and assessment of health risks from their consumption.

The levels of 12 trace metal (loid)s (TMs) in 10 vegetable types including leafy vegetables (purslane, purple basil and parsley) and fruiting vegetables (pepper, tomato, eggplant, cucumber, zucchini, green bean and melon) and in maize grown in Malatya province (Turkey) were investigated and non-carcinogenic health risks from consumption of these crops were assessed. The levels of TMs were measured by inductively coupled plasma-optical emission spectrometry. The mean levels of Ni, Cu, Cd, Cr, As and Zn in all crops were below maximum permissible concentrations (MPCs), while those of Pb in pepper (0.109 mg/kg fw), eggplant (0.103 mg/kg fw) and green bean (0.177 mg/kg fw) slightly exceeded MPCs (0.1 mg/kg fw). Leafy vegetables had relatively higher concentrations of Al, As, Ba, Cr, Cu, Fe and Mn compared to fruiting vegetables and maize. The estimated daily intake value of each TM estimated for each crop was found to be below the tolerable daily intake value. The target hazard quotients of all TMs in all crops did not exceed the acceptable non-carcinogenic risk level. However, hazard index (HI) value (1.57) in tomato was found to be above the threshold value of 1, indicating non-carcinogenic risks for consumers due to the intake of combined TMs in tomato. The THQ values of As, Co and Pb contributed 46.4%, 24.5% and 16.4% of the HI value of tomato, respectively. High daily consumption amount of tomato likely resulted in high HI value. The findings obtained in this study reveal that even if the levels of TMs in vegetables are safe, more attention should be paid to non-carcinogenic risks associated with TMs as a result of high vegetable intake.

Environmental, ecological and health risks of trace elements, and their sources in soils of Harran Plain, Turkey.

Soil pollution with trace elements (TEs) has become an increasingly serious environmental concern, however, assessment of ecological and human health risks especially in intensive agricultural regions remains limited. In this study, the contents of ten TEs (Al, As, Pb, Cr, Cu, Zn, Ni, Co, Mn and Fe) in soil samples from 204 sampling sites in the Harran Plain (Turkey) were examined to evaluate possible sources, pollution status and environmental, ecological and health risks of these elements. Only As and Ni exceeded the upper continental crust concentrations. Among ten TEs, Ni and As had the highest mean values of enrichment factor (EF) and contamination factor (Cf), indicating that soils showed moderate enrichment and moderate contamination with these elements. Ecological risk factor and ecological risk index values of all samples were <40 and <150, respectively, indicating low ecological risk in the study area. Factor analysis and correlation analysis indicated that Al, Pb, Cr, Cu, Zn, Co, Mn and Fe mainly originated from natural sources, Ni from mixed sources of anthropogenic and lithogenic origins, while arsenic primarily originated from anthropogenic activities. The hazard quotient values for both adults and children did not exceed 1, suggesting that all TEs in soil through ingestion, dermal contact and inhalation pathways had no significant non-carcinogenic risks. Children were more susceptible to non-carcinogenic health effects of TEs in soils. The carcinogenic risk values of As, Co, Cr and Ni were within the acceptable risk range, indicating that carcinogenic risks were not expected.