On-Line Microbial Whole Effluent Toxicity Monitoring for Industrial Wastewater

Conference · Tue Sep 17 04:00:00 EDT 2002

OSTI ID:15002969

Mathews, S; Hoppes, W; Mascetti, M; Campbell, C G

In this study a respirometer is tested for its ability to act as an early upset warning device and whole effluent toxicity monitor for industrial discharge. Industrial discharge water quality is commonly evaluated by comparing measured chemical concentrations to target values or regulatory limits established by governmental agencies. Unless the regulatory values are based upon empirical data, the actual effect of the discharge on aquatic systems is unknown. At the same time assessing the environmental toxicology of wastewater discharges is complicated by synergistic relationships among chemical constituents producing greater total toxicity. For example, metals may be more toxic in waters with low total hardness or more soluble at lower pH. An alternative approach that we are investigating is whole effluent toxicity testing. This study investigates the measurement of whole effluent toxicity through an on-line respirometer that measures toxicity to microorganisms comprising activated sludge. In this approach the oxygen uptake rate is monitored and used as an indicator of microbial activity or health. This study investigates the use of an online whole effluent toxicity testing system to provide early upset warning and the consistency of measured response to low pH. Repeated exposure of the microorganisms to low pH results in reduced sensitivity of the microbial population. We investigate whether this reduction in sensitivity results from physiological acclimation or changes in species composition. We identify promising applications, where, with proper calibration, respirometry based toxicity monitoring appear to be well suited for relative comparisons of whole effluent toxicity.

• Research Organization: Lawrence Livermore National Lab., CA (US)
• Sponsoring Organization: US Department of Energy (US)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 15002969
• Report Number(s): UCRL-JC-149442
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
CALIBRATION
CONTAMINATION
HARDNESS
MICROORGANISMS
MONITORING
MONITORS
OXYGEN
SENSITIVITY
TARGETS
TESTING
TOXICITY
WATER QUALITY