Cadmium inhibition of the biological removal of mercury from contaminated waste

Conference · Fri Jan 01 00:00:00 EST 1988

OSTI ID:7036498

Choudhury, G S; Hansen, C L ^[1]

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1. Dept. of Nutrition and Food Sciences, Utah State Univ., Logan, UT (US)

Toxic and potentially hazardous heavy metals are found in waste water from many industrial sources. Among these compounds, mercury is one of the most toxic and significant examples of heavy metal pollution. Mercury resistant strains of bacteria have been successfully used for biological detoxification of mercury. A concentration of 70 mg/L of mercury was tolerated and successfully removed by volatilization from the influent sewage. The continuous mercury removal was accomplished by a relatively stable mixed population of mercury resistant bacteria under non- sterile conditions. The detoxification of mercury carried out by mercury resistant bacteria is believed to be a NADPH dependent enzyme catalyzed reduction of mercuric ion to volatile metallic mercury. The enzyme responsible for this transformation is mercuric reductase which is a soluble flavoprotein located in the cytoplasm. Mechanistically, it is similar to enzymes in the class of FAD containing disulfide reductases and requires an excess of exogenous thiols for activity. Biological processes that employ microorganisms to achieve various biochemical transformations are sensitive to the presence of toxic organic and inorganic compounds. Metals, especially the heavier ones, are one of the toxicant groups that Inerfxere with the activities of microorganisms. According to Rinderle et al. and Izaki, cadmium, silver, copper and gold are potent inhibitors of the enzyme mercuric reductase. For the successful design and control of biological reduction of mercuric ion to metallic mercury in complex waste streams, an understanding is needed of the influence of additional components in the waste stream on the rate and efficiency of mercury volatilization. This book describes the study which was undertaken in an attempt to evaluate the effects of cadmium on the biological detoxification of mercury in defined media.

• OSTI ID: 7036498
• Report Number(s): CONF-880679-
• Resource Relation: Conference: 81. annual meeting of Air Pollution Control Association, Dallas, TX (USA), 19-24 Jun 1988; Other Information: Technical Paper 88-8.7; Related Information: Volume 1
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
54 ENVIRONMENTAL SCIENCES
29 ENERGY PLANNING
POLICY AND ECONOMY
INDUSTRIAL WASTES
MATERIALS RECOVERY
WASTE WATER
CHEMICAL COMPOSITION
CADMIUM
CHEMICAL REACTION KINETICS
ENZYME ACTIVITY
HAZARDOUS MATERIALS
MERCURY
POLLUTANTS
TECHNOLOGY ASSESSMENT
THIOLS
TOXICITY
WATER TREATMENT
ELEMENTS
HYDROGEN COMPOUNDS
KINETICS
LIQUID WASTES
MANAGEMENT
MATERIALS
METALS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
OXYGEN COMPOUNDS
PROCESSING
REACTION KINETICS
RECOVERY
WASTE MANAGEMENT
WASTE PROCESSING
WASTES
WATER
320305* - Energy Conservation
Consumption
& Utilization- Industrial & Agricultural Processes- Industrial Waste Management
540320 - Environment
Aquatic- Chemicals Monitoring & Transport- (1990-)
290300 - Energy Planning & Policy- Environment
Health
& Safety