Autor(es): Paiva, Maria João Dias
Data: 2008
Identificador Persistente: http://hdl.handle.net/10400.5/579
Origem: Repositório da UTL
Assunto(s): batata; cenoura; pesticida; efeito tóxico; água superficial; potato; carrot; pesticide; toxic effects; surface water
Mestrado em Engenharia Agronómica - Instituto Superior de Agronomia
An ecotoxicological characterisation of the potential hazard of the registered pesticides for potato and carrot was made throught modelling. It was evaluated surface water exposure to pesticides and toxic effects to aquatic biota in an agricultural area of the sub-basin South Estuary, where those crops have particular importance. Pesticide analysis in water was performed by solid phase microextraction (SPME) followed by gas chromatography-mass spectrometry (GC-MS). Acute toxic effects were determined by microbiotests on the basis of Daphnia magna crustacean and Pseudokirchneriella subcapitata algal. In 15 surface water samples, detection frequency was higher for the herbicides metribuzine, terbuthylazine and the insecticide chlorpyrifos. The maximum value of growth inhibition for algal was 62,42% in a sample from a lake, where the higher pesticide concentration level (metribuzine, 17,02 µg/L) was also registered. Immobility values to the crustacean were below 30%. The results showed that environmental conditions and agricultural management, namely pesticide use, associated to their potential contamination, and irrigation, influence surface water contamination by those products, pointed out the need for their adequate selection.
