Author details

4. Conclusions

288 Water Quality

ronmental pollution.

below the admissibility limits.

estimated to 90 mg kg−<sup>1</sup>

).

The metals are considered to be one of the main sources of environmental pollution, having a significant effect on the ecological quality. Potentially toxic metals derived from the anthropogenic activities may lead to severe disturbances in the ecosystems, and therefore, the identification of pollution sources along with the assessment of the long‐term pollution potential is a must in order to take actions for reducing or stopping the pollution. The anthropogenic sources lead to an increase in the metals levels in the environment due to the industrial and atmospheric pollution and their accumulation in soil, affecting thus the ecosystems. Therefore, measurements of metals in soil, plants, and sediment are very important in monitoring envi-

The primary objective of this study investigation was to characterize the surrounding areas of raw water reservoirs in terms of the content in heavy metals and rare earth, linked to establishing the supply mechanism of these surface waters. High accuracy measurements for quality assessment were performed on water samples, in terms of toxic metals, over a period of 3 years: 2009, 2010, and 2011. An increase (2009–2011) in the levels of Al and Mn was registered in three sampling sites (Somes Cald River, the confluence Somes Cald/Somes Rece, and Somes Cald Lake); of Zn and Pb to Tarnita site; of Fe, Ti, Zn, and Pb to the Somes Cald River; of Cu and Pb to the confluence Somes Cald/Somes Rece; and of Fe and Cu to the Somes Rece Lake. A large increase in the content of Zn and As was reported in 2011 for all the areas, but

Water quality is influenced by weather conditions, and this was revealed by studying their influence on the content of metals in water samples from the same area, but different calendar period. There is a variation in the concentrations of heavy metals observed in the studied

Determination of rare earths in various types of environmental samples is particularly important because it can serve to establish a fingerprint sample, and so the results could be used in determining the origin of the sample in question and to identify sources of pollution. Comparing the data of the 3 years, 2009, 2010, 2011, from the same month of sampling, there is a constant concentration of rare metals, except for Sc, where there is a significant decrease from 2009. Heavy metals are one of the main sources of pollution of the aquatic environment, they tend to adsorb in sediment, and the study of the adsorption/desorption effect of heavy metals in sediment and sediment transport has a particular importance. The concentration levels for most metals in sediment samples collected from the study area were within the general admissibility limits, with exception of As which was present in sediment samples taken in 2010 in quantities that exceeded the mean admitted (in the sediment samples collected from Areas 4—Warm Somes, 5—confluence Somes Cald/Somes Rece); also in the Area 4—Somes

We found higher values of metal concentrations in sediments taken from lake versus concentration values in sediment samples taken from the river water. In soil samples taken from the same areas, in the same calendar period (2009 and 2010), an increase in the concentrations of Pb and As was observed and a decrease in the content of Co (for soil sampled in 2010).

matrices (water, sediment, soil) depending on season, for certain periods of the year.

Cald was registered a significant increase in the Cr content (150 mg kg−<sup>1</sup>

Cezara Voica<sup>1</sup> , Andreea Maria Iordache<sup>2</sup> \*, Roxana Elena Ionete<sup>2</sup> and Ioan Ștefănescu2

\*Address all correspondence to: andreea.iordache@icsi.ro

1 National Institute for Research and Development of Isotopic and Molecular Technologies, Cluj‐Napoca, Romania

2 National Research and Development Institute for Cryogenics and Isotopic Technologies, Ramnicu Valcea, Romania
