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Cadmium: An IntroductionAshley Holland

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OUTLINEIntroductionRecognitionEvaluationControlSummary & Conclusion

BACKGROUND INFORMATIONWhat is cadmium?Soft and malleableBluish-whiteMetal Where is cadmium found?Naturally occurring Zinc smeltingGreenockite (Cadmium sulfide)

THE HISTORY OF CADMIUMApothecaries in Germany would make zinc oxide using cadmia (zinc carbonite)Discovered in 1817 by Freidrich Stromeyer, when he researched the discoloration of the melted cadmiaKarl Meissner and Mark Karsten also made the same discoveries as Freidrich Stromeyer in 1817Cadmium was named after the mineral cadmiaBrown oxide + Carbon = Cadmium

MODERN APPLICATIONS OF CADMIUM Mostly obtained from zinc byproducts from smelting The #1 use is for nickel-cadmium batteriesBetter performance than most other batteriesUsed in pigments, stabilizers, and coatings Pigments: withstand high temperatures and pressures without fadingStabilizers: slow down the degradation of polyvinylchloride (PVC)Coatings: used as plating on steel; does not corrode easilyAbout 25,000 tons of cadmium is released into the environment each yearApproximately 17,500 tons are released into rivers

IMPORTANT PROPERTIES OF CADMIUMInorganic substance; natural substanceOdorlessHighly resistant to corrosionBurns in powdered formCorrosive fumesToxic and CarcinogenicTeratogenic

CADMIUM EXPOSURECadmium is used in many industries because of its propertiesManufacturing & Construction are the primary industriesApproximately 30,000 workers are exposed to cadmium (U.S.)The general public can also be exposed to cadmiumDrinking WaterAirCigarette SmokeFood (introduced via agricultural soils)

OSHA VS. CADMIUMOSHA PEL/Action Level: General Industry1910.1027 (c): Five micrograms per cubic meter of air1910.1027 (b): Two and a half micrograms per cubic meter of airOther industries such as shipyards, construction, and agriculture have separate standards, but their OSHA PELs/Action Levels were the sameImmediately Dangerous to Life and Health (IDLH): NIOSHSet at nine milligrams per cubic meter

TOXICOLOGY PROFILE OF CADMIUMCadmium is highly toxic and is a known carcinogenAttacks the bodys systemsCardiovascular Renal Gastrointestinal NeurologicalReproductiveRespiratory Routes of exposureInhalationIngestion Dermal Exposure

Symptoms Include:Nausea and vomiting Stomach crampsShortness of breathKidney damageFragile bonesSwelling (nose and throat)Death

EPIDEMIOLOGICAL STUDY ON CADMIUMResearchers noted that workers who are exposed to cadmium have higher rates for lung and prostate cancerStudy was conducted on manufacturing workersWeak statistical relationship between the cancers and cadmiumA relationship between cancer and cadmium exposure exists in those who have also been exposed to arsenic

EVALUATING CADMIUMCadmium samples are collected as air samplesSample Equipment37-mm diameter filter cassette Contains cellulose mixed ester membrane filterRecommended air volume and sampling rate:960 L at 2.0 L/minSamples are diluted and analyzed using either flame atomic absorbent spectroscopy or flameless atomic absorbent spectroscopy

CONTROLLING CADMIUM EXPOSUREELIMINATIONSUBSTITUTION ENGINEERING CONTROLSVentilation IsolationADMINISTRATIVE CONTROLSImplement worker-rotationEmployee trainingNo smoking, eating, drinking, etc. around cadmiumPERSONAL PROTECTIVE EQUIPMENTSafety gogglesBreathing protection such as a respirator

SUMMARY & CONCLUSIONCadmium is a naturally occurring metal, found mostly by smelting zincThe use of cadmium will most likely increase because of its beneficial propertiesLightweight and able to withstand high/low temperatures and pressure Does not corrode easilyExposure to cadmium affects several systems of the bodyKnown carcinogenSamples are collected using the air sampling methodsAnalysis of samples require spectroscopyThe best way to reduce cadmium exposure is to eliminate/substitute it completely

REFERENCEShttp://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

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