Appraisal of metallic accumulation in the surface sediment of a fish breeding dam in Türkiye: A stochastical approach to ecotoxicological risk assessment.

This study examines the levels and patterns of potentially toxic elements (PTEs) in surface sediment of Almus Dam Lake (ADL), a key fish breeding site in Türkiye. PTE concentrations in sediment were ranked: Hg (0.05 ± 0.01) < Cd (0.16 ± 0.01) < Pb (9.34 ± 1.42) < As (18.75 ± 15.65) < Cu (63.30 ± 15.17) < Ni (72.64 ± 20.54) < Zn (86.66 ± 11.95) < Cr (108.35 ± 36.40) < Mn (1008 ± 151) < Fe (53,998 ± 6468), with no significant seasonal or spatial differences. Ecological risk indices (mHQ, EF, Igeo, CF, PLI, Eri, mCd, NPI, PERI, MPI, and TRI) showed low contamination levels. Health risk assessments, including LCR, HQ, and THI, indicated minimal risks to humans from sediment PTEs. Statistical analyses (PCA, HCA, SCC) identified natural, transportation, and anthropogenic PTE sources, with slight impacts from agriculture and fish farming. This research underlines contamination status of ADL and emphasizes the need for targeted management strategies, offering critical insights for environmental safeguarding.

Metal pollution assessment in the surface sediments of a river system in Türkiye: Integrating toxicological risk assessment and source identification.

This study investigates potentially toxic elements (PTEs) in the surface sediments of the Abdal River system, a critical water source for Samsun province, Türkiye, due to the presence of the Çakmak Dam. PTE concentrations, measured in mg/kg, show significant variability: Hg (0.03) < Cd (0.26) < As (10.98) < Pb (13.88) < Cu (48.61) < Ni (62.45) < Zn (70.97) < Cr (96.28) < Mn (1015) < Fe (38357). Seasonal variations were observed, in particular increased concentrations of As, Cd and Pb in summer (p < 0.05). Contamination and ecological risk indices (mHQ, EF, Igeo, CF, PLI, Eri, mCd, NPI, PERI, MPI, and TRI) indicate moderate to low levels of contamination, suggesting potential ecological effects. Health risk assessments suggest minimal risks to human health from sediment PTEs. Statistical analyses (PCC, PCA and HCA) improve the understanding of the sediment environment and contamination sources, while the coefficient of variation assists in source identification.

Potentially hazardous elements in sediments and Ceratophyllum demersum: an ecotoxicological risk assessment in Miliç Wetland, Samsun, Türkiye.

Potentially hazardous elements (PHEs) are non-biodegradable and accumulate in places like water, soil, and plants where they endanger environmental health. There are a considerable number of wetlands having both national and worldwide importance in Türkiye. Regarding PHE accumulation, sediments and Ceratophyllum demersum were examined in the Miliç Wetland (MW), situated in a basin with intense hazelnut and rice farming, which is next to the international highway on the Central Black Sea Coast of Türkiye. The quantification of PHEs in the study subjects was undertaken using a validated inductively coupled plasma-mass spectrometry (ICP-MS) method, and mean concentrations (mg/kg) of PHEs in the sediments were in the order of Al (13,133) > Fe (10,790) > Mn (205.84) > Cu (17.95) > Cr (16.40) > Zn (15.55) > Ni (11.74) > Pb (9.17) > Co (6.30) > As (2.07) > Cd (0.19). The ecotoxicological risk was assessed using sediment quality guidelines (SQGs) and certain geological indices, indicating mostly low ecological risk, low pollution, and no hazardous risk. Based on the modified hazard quotient (mHQ) classification of values, Ni showed low contamination, while Cd, Pb, As, and Cu displayed very low contamination, and Zn presented minor contamination. The findings of total lifetime cancer risk (LCR), hazard quotient (HQ), and hazard index (HI) identified that exposure of adults or children to sediments containing PHEs would not represent a major health risk. As a recommendation, it is necessary to avoid the direct entrance of agricultural pesticides and fertilizers to enhance the sediment quality of the MW. Since the highway was constructed close to MW, this is considered a significant source of human-caused pollution. Consequently, all PHEs analyzed, except for Cd, displayed a bioconcentration factor (BCF) value of more than 1000, indicating that Ceratophyllum demersum is a promising plant for phytoremediation in PHE-polluted ecological systems involving wetlands, and it can efficiently be employed as an indicator species in biological screening investigations.

Evaluation of metal accumulation in Terme River sediments using ecological indices and a bioindicator species.

Freshwater resources are hotspot areas for sustainable water use. Surface sediment samples from four stations in Terme River were collected seasonally between April 2019 and January 2020. Sample collection from 0 to 10 cm depth of the riverbed was carried out with an Ekman Dredge Grab. Cu, Pb, Zn, Ni, Mn, Fe, Co, As, Cr, Cd, and Al concentrations were determined with an inductively coupled plasma-mass spectrometry (ICP-MS). The percentage of organic matter in the sediment was evaluated by the combustion method. pH measurements were made with a pH meter. The concentrations of elements measured are listed in descending order as follows: Fe > Al > Mn > Cr > Cu > Zn > Ni > Co > Pb > As > Cd. Enrichment factor (EF), contamination factor (CF), and geo-accumulation index (Igeo) are the most commonly used tools to determine whether elements are of natural origin or anthropogenic origin. According to average EF values, the metals are listed as follows: Cd > Cu > Co > Fe > Cr > Pb > Mn > Zn > Al > Ni > As. The CF and Igeo values are listed as follows: Cd > Cu > Co > Fe > Cr > Pb > Mn > Zn > Al > Ni > As. According to EF results, Cd and Cu originate from human activities. The CF and Igeo indicate minimal enrichment for all metals. Potential ecological risk (PERI), pollution load (PLI), modified hazard quotient (mHQ), ecological contamination (ECI), and toxic risk indices (TRI) indicate low risk in the region. Human health risk indices also show that carcinogenic and noncarcinogenic risks are low. In the bioaccumulation evaluation performed on Myriophyllum spicatum species, it was determined that the plant accumulated Mn, Co, Ni, Cu, Zn, As, and Cd. These results show that Myriophyllum spicatum can be used as a bioindicator.

Comprehensive assessment of water quality and associated health risk by using physicochemical quality indices and multivariate analysis in Terme River, Turkey.

The ecosystem and water quality of Terme River, an essential drinking and irrigation water source in the region, are at risk due to anthropogenic pressures. Therefore, the present study aim to present a comprehensive overview of the water quality state and pollution sources of the river. Some physicochemical water quality parameters were analyzed by standard methods along the surface water of river spatiotemporally. The concentrations of major elements and heavy metals (Na, Mg, K, Ca, Al, Cr, Fe, Co, Mn, Ni, Zn, Cd, Cu, Pb, As) were measured in water samples. Relationships between physicochemical data were assessed by using multivariate statistical analysis (MSA) methods. The order of the mean values of cations were as follow: Ca2+ > Mg2+ > Na+ > K+ > NH4+ (32.66, 26.82, 13.29, 6.45, 0.305; mg/L), and order of anions: SO42- > NO3- >F- > NO2- (7.88, 3.988, 1.01, 0.0316; mg/L). Increases in ion concentrations in the downstream zone have been monitored in the summer and autumn months. Average water quality index (WQI) 22, heavy metal pollution index (HPI) 15.61, heavy metal evaluation index (HEI) 0.78, and nutrient pollution index (NPI) 0.404 values indicated that the general water quality of Terme River was fine. All hazard quotient (HQ) and hazard index (HI) values in this study were calculated below the risk threshold (<1). HI-total values (2.48E-01) in children were higher than in adults (2.14E-01). This suggests that children's health is at higher risk than adults. Principal component analysis (PCA) data formed four principal components (PCs) explaining 85.22% of the total variance. These PCs revealed that the significant changes in water quality occurred from point and diffuse sources, including rock types of the basin, soil erosion, domestic wastewater discharges, and agricultural flow of inorganic fertilizers.