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Transcript of Cadmium Presentation
CADMIUM: AN INTRODUCTIONAshley Holland
OUTLINE
Introduction Recognition Evaluation Control Summary & Conclusion
BACKGROUND INFORMATION
What is cadmium? Soft and malleable Bluish-white Metal
Where is cadmium found? Naturally occurring Zinc smelting Greenockite (Cadmium sulfide)
THE HISTORY OF CADMIUM
Apothecaries in Germany would make zinc oxide using cadmia (zinc carbonite)
Discovered in 1817 by Freidrich Stromeyer, when he researched the discoloration of the melted cadmia
Karl Meissner and Mark Karsten also made the same discoveries as Freidrich Stromeyer in 1817
Cadmium was named after the mineral cadmia Brown oxide + Carbon = Cadmium
MODERN APPLICATIONS OF CADMIUM
Mostly obtained from zinc byproducts from smelting The #1 use is for nickel-cadmium batteries
Better performance than most other batteries
Used in pigments, stabilizers, and coatings Pigments: withstand high temperatures and pressures without fading Stabilizers: slow down the degradation of polyvinylchloride (PVC) Coatings: used as plating on steel; does not corrode easily
About 25,000 tons of cadmium is released into the environment each year
Approximately 17,500 tons are released into rivers
IMPORTANT PROPERTIES OF CADMIUM
Inorganic substance; natural substance Odorless Highly resistant to corrosion Burns in powdered form Corrosive fumes Toxic and Carcinogenic Teratogenic
CADMIUM EXPOSURE
Cadmium is used in many industries because of its properties Manufacturing & Construction are the primary industries
Approximately 30,000 workers are exposed to cadmium (U.S.) The general public can also be exposed to cadmium
Drinking Water Air Cigarette Smoke Food (introduced via agricultural soils)
OSHA VS. CADMIUM
OSHA PEL/Action Level: General Industry 1910.1027 (c): Five micrograms per cubic meter of air 1910.1027 (b): Two and a half micrograms per cubic meter of air
Other industries such as shipyards, construction, and agriculture have separate standards, but their OSHA PELs/Action Levels were the same
Immediately Dangerous to Life and Health (IDLH): NIOSH Set at nine milligrams per cubic meter
TOXICOLOGY PROFILE OF CADMIUM
Cadmium is highly toxic and is a known carcinogen
Attacks the body’s systems Cardiovascular Renal Gastrointestinal Neurological Reproductive Respiratory
Routes of exposure Inhalation Ingestion Dermal Exposure
Symptoms Include: Nausea and vomiting Stomach cramps Shortness of breath Kidney damage Fragile bones Swelling (nose and throat) Death
EPIDEMIOLOGICAL STUDY ON CADMIUM
Researchers noted that workers who are exposed to cadmium have higher rates for lung and prostate cancer
Study was conducted on manufacturing workers Weak statistical relationship between the cancers and
cadmium A relationship between cancer and cadmium exposure
exists in those who have also been exposed to arsenic
EVALUATING CADMIUM
Cadmium samples are collected as air samples Sample Equipment
37-mm diameter filter cassette Contains cellulose mixed ester membrane filter
Recommended air volume and sampling rate: 960 L at 2.0 L/min
Samples are diluted and analyzed using either flame atomic absorbent spectroscopy or flameless atomic absorbent spectroscopy
CONTROLLING CADMIUM EXPOSURE
ELIMINATION SUBSTITUTION ENGINEERING CONTROLS
Ventilation Isolation
ADMINISTRATIVE CONTROLS Implement worker-rotation Employee training No smoking, eating, drinking, etc. around cadmium
PERSONAL PROTECTIVE EQUIPMENT Safety goggles Breathing protection such as a respirator
SUMMARY & CONCLUSION
Cadmium is a naturally occurring metal, found mostly by smelting zinc The use of cadmium will most likely increase because of its beneficial
properties Lightweight and able to withstand high/low temperatures and pressure Does not corrode easily
Exposure to cadmium affects several systems of the body Known carcinogen Samples are collected using the air sampling methods Analysis of samples require spectroscopy The best way to reduce cadmium exposure is to eliminate/substitute it
completely
REFERENCES
http://www.cadmium.org/cadmium-applicationshttp://www.rsc.org/periodic-table/element/48/cadmiumhttp://www.atsdr.cdc.gov/toxguides/toxguide-5.pdfhttp://www.atsdr.cdc.gov/substances/toxsubstance.asp?toxid=15http://www.dguv.de/medien/ifa/en/pub/ada/pdf_en/aifa0049e.pdfhttps://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=10035https://www.osha.gov/SLTC/cadmium/http://www.lenntech.com/periodic/elements/cd.htmhealth.cvs.com/GetContent.aspx?token=f75979d3-9c7c-4b16-af56-3e122a3f19e3&chunkiid=120796#symptomshttp://www.atsdr.cdc.gov/csem/cadmium/docs/cadmium.pdfhttps://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=10040http://www.cdc.gov/niosh/ipcsneng/neng0020.html