RESUMEN
This paper reports the results of mercury contamination monitoring in the Cecina river basin (Tuscany, Italy). Mercury was measured in the waters, sediments and fish species of the river and its most important tributaries. In fish specimens the organic form was also determined. The results showed high mercury levels in most of the samples analysed. Particularly high concentrations were found in the sediments of the S. Marta canal flowing into the Cecina, where a chlor-alkali plant discharges its wastes, and high levels were still detectable 31 km downstream from the confluence. Near the S. Marta confluence many fish specimens were very contaminated and a study on Leuciscus cephalus cabeda growth suggested that at this site mercury accumulation occurs in these organisms since they are very young.
Asunto(s)
Peces/fisiología , Mercurio/análisis , Mercurio/toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad , Animales , Monitoreo del Ambiente/métodos , ItaliaRESUMEN
In the northern part of Pisa Province (Tuscany, Italy), the use of lichens as both airborne trace element biomonitors and air quality bioindicators is described. The following elements were analysed in Xanthoria parietina: As, Cd, Cr, Ni, Pb, V, Zn and Hg, and the results are compared with those we previously obtained in Livorno Province (Tuscany) using the same lichen species. The results identify spots of different environmental metal contamination and air quality. Median values of Pb, V and Ni concentrations were much lower than those of Livorno Province, with maximum values even nine times lower. Arsenic contamination was also lower, while Cd, Hg and Zn levels were similar in the two areas. In Pisa Province, the highest levels of contamination were recorded for Zn, Pb, Cr and Ni, and a degree of agreement was found between air quality and metal concentrations in lichens. The air quality in Pisa Province is better than in Livorno Province, even if the different climatic and orographic features of the two areas may influence the presence of lichen species and thus an assessment of air quality.
Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Líquenes/química , Metales Pesados/análisis , Oligoelementos/análisis , Contaminantes Atmosféricos/farmacocinética , Clima , Geografía , Italia , Metales Pesados/farmacocinética , Valores de Referencia , Reproducibilidad de los Resultados , Oligoelementos/farmacocinéticaRESUMEN
This paper reports the results of a monitoring programme of six rivers (Serchio, Cecina, Cascina, ERa, Elsa and Pavone) that drain north-west Tuscany (Italy). In this area, agricultural, industrial and urbanization pressures affect water quality, also in terms of suitability for the survival of aquatic organisms. The river waters were monitored for several physico-chemical parameters (temperature, dissolved oxygen, suspended solids, total ammonia, nitrites, Cu, Cd, Cr, Ni and Pb) in order to assess the anthropogenic impact on the environmental conditions of these watercourses and their suitability for fish life. Statistical data handling was performed for each river and the percentage of physico-chemical parameters that, according to the E.C. law, were over the limits that must not be exceeded to protect fish life, was calculated and a classification was made of the six rivers in this sense. Concerning the metals, inter-element relationships (between chromium and nichel, lead and copper, nichel and lead and copper, copper and lead) were found which allow some remarks on the origins of the anthropogenic impacts, and comparisons were made with two metal-polluted watercourses in northern Italy, the Po and Lambro rivers. From the comparison, the Tuscan rivers showed generally lower metal contamination, especially with respect to the Lambro.