Assessing the Quality of Freshwaters in a Protected Area within the Tagus River Basin District (Central Portugal).

The article examines water-sediment quality in an agricultural zone of a protected area within the Tagus River basin district in central Portugal. During four sampling occasions, 4 herbicides, 2 insecticides and the metabolite 3,4-dichloroaniline were detected in surface water samples at four sites and in groundwater samples from six wells. Measured concentrations were compared with parametric values for human consumption, groundwater quality standards, and environmental quality standards applicable to surface water set in European Union legislation. Most severe adverse effects were found on the growth of the algae Pseudokirchneriella subcapitata and lethality of the crustacean Daphnia magna in nondiluted water samples.