Development of a microbial toxicity monitor

In context of the current state of microbial toxicity monitoring systems, a need was recognized for further work on dissolved oxygen (DO) monitoring technique to establish the concept's validity and to improve upon both sensitivity and design using the experience of existing variations covered in the literature. Higher flow velocity, no moving parts, removal of the DO probe from direct contact with the aeration chamber, and a packed bed biofilter were the design features incorporated into the microbial toxicity monitor (MTM) described herein. Results obtained from testing five heavy metals, four organics and pH indicated that there was a direct relationship between concentration of contaminants and MTM response. The MTM can be useful as a primary tier monitoring system because of its continuous flow operation, automation, low cost, and ease of maintenance.