An approach for assessment of water quality using semipermeable membrane devices (SPMDs) and bioindicator tests

As an integral part of our continued development of water quality assessmen t approaches, we combined integrative sampling, instrumental analysis of wi dely occurring anthropogenic contaminants, and the application of a suite o f bioindicator tests as a specific part of a broader survey of ecological c onditions, species diversity, and habitat quality in the Santa Cruz River i n Arizona, USA. Lipid-containing semipermeable membrane devices (SPMDs) wer e employed to sequester waterborne hydrophobic chemicals. Instrumental anal ysis and a suite of bioindicator tests were used to determine the presence and potential toxicological relevance of mixtures of bioavailable chemicals in two major water sources of the Santa Cruz River. The SPMDs were deploye d at two sites; the effluent weir of the International Wastewater Treatment Plant (IWWTP) and the Nogales Wash. Both of these systems empty into the S anta Cruz River and the IWWTP effluent is a potential source of water for a constructed wetland complex. Analysis of the SPMD sample extracts revealed the presence of organochlorine pesticides (OCs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs). The bioindicator test s demonstrated increased liver enzyme activity, perturbation of neurotransm itter systems and potential endocrine disrupting effects (vitellogenin indu ction) in fish exposed to the extracts. With increasing global demands on l imited water resources, the approach described herein provides an assessmen t paradigm applicable to determining the quality of water in a broad range of aquatic systems. (C) 2000 Elsevier Science Ltd. All rights reserved.