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Removal of Trace Elements by Cupric Oxide Nanoparticles from Uranium In Situ Recovery Bleed Water and Its Effect on Cell Viability
Published on: June 21, 2015
Environmental transformation of toxic metals
M J Wade1, B K Davis, J S Carlisle
1Department of Toxic Substances Control, California Environmental Protection Agency Sacramento 95812-0806.
Occupational Medicine (Philadelphia, Pa.)
|July 1, 1993
Summary
Environmental metal transformations dictate human health risks. Key processes like adsorption, redox reactions, and bioaccumulation influence the toxicity of metals such as arsenic, lead, and mercury.
Area of Science:
- Environmental Chemistry
- Toxicology
- Geochemistry
Background:
- Metal toxicity is highly dependent on their chemical form.
- Environmental transformations significantly alter the bioavailability and hazard of metals.
- Understanding these processes is crucial for assessing human health risks.
Purpose of the Study:
- To detail the environmental transformation processes affecting metal toxicity.
- To examine the roles of specific metals (arsenic, cadmium, chromium, lead, mercury, selenium) in environmental contamination.
- To highlight the connection between environmental chemistry and human health hazards.
Main Methods:
- Review of environmental transformation processes: adsorption/desorption, oxidation-reduction (redox), biotic metabolism, organic compound formation, bioaccumulation.
- Focus on six key toxic metals: arsenic, cadmium, chromium, lead, mercury, and selenium.
- Analysis of metal occurrence at hazardous waste sites and their involvement in contamination.
Main Results:
- Environmental transformations, including adsorption, redox reactions, and bioaccumulation, critically control metal toxicity.
- The chemical state of metals is a primary determinant of their health hazard.
- Arsenic, cadmium, chromium, lead, mercury, and selenium are significant environmental contaminants due to their toxicity and prevalence.
Conclusions:
- Environmental transformations are the key factor in determining the human health risks posed by metals.
- Specific processes like redox reactions and bioaccumulation directly impact metal toxicity.
- The selected metals represent major environmental concerns requiring careful management.
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