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07:57
Effect of Microwave Synthesis Conditions on the Structure of Nickel Hydroxide Nanosheets
Published on: August 18, 2023
Temperature effect on nickel release in ammonium citrate.
Adriana R Oller1, Danielle Cappellini, Rayetta G Henderson
1NiPERA, Durham, NC 27713, USA. aoller@nipera.org
Journal of Environmental Monitoring : JEM
|September 3, 2009
Summary
Ammonium citrate leaching overestimates water-soluble nickel in workplace aerosols, especially with nickel carbonate and subsulfide. This finding necessitates reevaluating current exposure assessment methods for nickel compounds.
Area of Science:
- Occupational Health
- Environmental Chemistry
- Analytical Chemistry
Background:
- Ammonium citrate leaching is a standard method for assessing water-soluble nickel compounds in workplace aerosols.
- Accurate assessment of bioavailable nickel fractions is crucial for occupational health and safety.
- Existing methods may not fully represent the behavior of nickel compounds under physiological conditions.
Purpose of the Study:
- To evaluate the accuracy of ammonium citrate leaching in determining water-soluble nickel fractions.
- To compare ammonium citrate leaching with synthetic lung fluid under physiological conditions.
- To investigate the influence of specific nickel compounds (carbonate, subsulfide) on leaching results.
Main Methods:
- Leaching of workplace aerosols using ammonium citrate (Zatka protocol, step 1).
- Comparison of results with leaching using synthetic lung fluid at 37°C.
- Analysis of nickel fractions in the presence of nickel carbonate and subsulfide.
Main Results:
- Ammonium citrate leaching significantly overestimated the water-soluble nickel fraction by over tenfold.
- This overestimation was particularly pronounced when nickel carbonate and subsulfide were present.
- Results indicate a discrepancy between the standard leaching method and physiological conditions.
Conclusions:
- The ammonium citrate leaching method, as applied in the Zatka protocol, may not accurately reflect bioavailable nickel.
- Exposure matrices based on this method require reexamination due to potential overestimation.
- Further leaching studies on refinery particles are essential to refine nickel exposure assessment.
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