Changes in physicochemical and toxicological parameters of waters of Trincheira's River caused by road construction

Alterações dos parâmetros físico-químicos e toxicológicos das águas do Rio da Trincheira afetadas por uma construção rodoviária

Abstract

Road infrastructures can greatly affect natural areas. A trench and a roundabout were constructed in the city of Francisco Beltrão-Paraná-Brazil over a water body called Trincheira's River. The present study evaluated the quality of the waters of Trincheira’s River, in physicochemical and toxicological terms, at four points along its course, during and after the trench and the roundabout construction. The results of the physicochemical analysis showed changes in some parameters analyzed near the road infrastructure, in particular, oils and greases, biochemical oxygen demand and dissolved oxygen. The immobility/mortality test with Artemia salina L. micro shellfish showed that none of the water at the collection points of the river was toxic. The cytotoxicity test with the bioindicator Allium cepa L. revealed no cytotoxic effect in the sample collection done during the road construction. However, after the finalization of the trench and the roundabout construction, a statistically significant increase in the percentage of the mitotic index at the road construction point was noticed. Therefore, awareness and regulatory measures are necessary to oversee activities on water bodies’ shores and environs, to ensure a harmonious relationship between human activity and the ecosystem.

Keywords:
Allium cepa L.; Artemia salina L.; bioindicators; water pollution; water quality.