Assessment of the Anthropogenic Impact and Distribution of Potentially Toxic and Rare Earth Elements in Lake Sediments from North-Eastern Romania

Abstract

Chemical analysis was performed on sediment samples collected in two sampling sessions (July and October) from Podu Iloaiei Dam Lake, one of the most important water resources used for aquaculture in north-eastern Romania. The concentration of 15 trace elements (TEs), 8 refractory elements (REs), and 15 rare earth elements (REEs)—determined using inductively coupled plasma mass spectrometry—showed variability largely dependent of the sampling points and collection time. Manganese was the most abundant TE, V and Cr were the most abundant REs, while Ce was one of the most abundant REEs. The cerium negative anomaly and Gd positive anomaly were observed in the Chondrite-normalized distributions. In October, the Ce anomaly showed significant negative correlation with Mn, emphasizing the water body oxidation potential. The identified positive Gd anomaly was most likely associated with the use of Gd-chelating agents in magnetic resonance imaging in Iasi, the largest medical hub in north-eastern Romania. Principal component analysis extracted three factors explaining 96.0% of the observed variance, i.e., rock weathering, leaching from soil surface, contributions from urban stormwater and atmospheric deposition (50.9%), pedological contributions (23.7%), and mixed anthropogenic sources (e.g., traffic, waste discharge, agricultural activities; 21.4%). The evaluation of pollution indices highlighted low and moderate degrees of contamination for most of the elements and a considerable degree of contamination for Cd. Assigned Cd sources included fertilizers and pesticides used in the near agricultural areas or the high traffic road located near the lake. Since contamination of aquatic ecosystems with harmful elements is a human health concern, further monitoring of specific vectors in the food chain of the investigated dam lake will be of the utmost importance.

Spatial Variability of Rare Earth Elements in Groundwater in the Vicinity of a Coal-Fired Power Plant and Associated Health Risk

“…Depletion or enrichment of an element in relation to its neighboring REE is considered a negative or positive REE anomaly. In this study, Ce, Eu, Tm, and Tb anomalies were calculated using Equations (1)–(4) adapted from the previous literature [ 4 , 37 , 38 ] as follows: where Ce / Ce *, Eu / Eu *, Tm / Tm *, and Tb / Tb * represent Ce, Eu, Tm, and Tb anomalies, respectively, while N stands for the UCC-normalized concentration values of the element.…”

“…Depletion or enrichment of an element in relation to its neighboring REE is considered a negative or positive REE anomaly. In this study, Ce, Eu, Tm, and Tb anomalies were calculated using Equations ( 1)-( 4) adapted from the previous literature [4,37,38] as follows:…”

“…These elements are typically classified based on their atomic radii and masses. This classification results in three groups: the light REEs (LREEs), which comprise lanthanoids from lanthanum (La) to neodymium (Eu), including scandium; the middle REEs (MREEs), which include lanthanoids from samarium (Sm) to dysprosium (Dy); and the heavy REEs (HREEs), which comprise lanthanoids from holmium (Ho) to lutetium (Lu), including yttrium [ 3 , 4 ].…”

Ecological and Health Risks Attributed to Rare Earth Elements in Coal Fly Ash

“…Normalization and anomaly calculation of the REYs in CFA can provide information regarding the fraction pattern, enrichment level, and provenance composition [ 7 , 41 , 55 ]. In this study, a Ce anomaly and Eu anomaly were used to reflect the geochemical parameters of REYs in the CFA.…”

Developing an Intelligent Data Analysis Approach for Marine Sediments

“…The factors affecting the chemical and physicochemical properties of marine sediments are closely related to various natural and anthropogenic events, and it is a real scientific challenge to use their specific assessment as a convenient mode of indicating different sides of environmental pollution discharges. There are various studies that attempt to evaluate the impact of different factors on marine sediment quality using classical univariate statistical methods such as regression or correlation analysis, where the purpose is to find reliable links between chemical or physicochemical monitoring values each other or related to indicators such as depth, geographical location or vicinity to pollution sources [ 1 , 2 , 3 , 4 , 5 , 6 , 7 ]. In most of these regression or correlation studies, the basic goal is after the selection of important tracers to point out the relationship between sediment composition and the sediment morphologic features or diagenesis [ 8 , 9 , 10 ].…”