Optimizing the In Situ Identification Evaluation System Health: Ammonia and Zinc as Examples

Abstract

Anthropogenic influences on the environment have increased the levels of contaminants and pollution in aquatic ecosystems humans and wildlife depend on for water resources. It is especially important to be able to accurately and efficiently evaluate riverine contamination. The United States Environmental Protection Agency developed toxicity identification evaluation (TIE) protocols for evaluating sediment and surface water toxicity in a laboratory setting. Following this framework, Burton and Nordstrom developed an in-situ toxicity identification evaluation (iTIE) system, which allows for the toxicity analysis to be done in the field to avoid artifacts introduced when samples are transported to the laboratory.19 The tests presented in this paper provide data to further optimize the iTIE system through the evaluation of different resin (chelex, charcoal, and zeolite) and pollutant or contaminant (ammonia, zinc, nickel, and vanadium) combinations. The experimental results indicate that at least 3-5 grams of resin is needed for significant contaminant removal, the system flow must be maintained below 14 ml/min, and the iTIEs can transition successfully into Phase II of the TIE protocol by allowing for specific contaminant characterization.