Heavy Metal and People Flashcards
Arsenic
Form of white arsenic trioxide
Highly favored due to odorless, easily incorporated into food and drink
Undetectable in the body
Before advent of the March Test
In France, it came to be known as “inheritance powder”
Arsenic poisoning would have symptoms similar to cholera
Number of chemist worked on the identification of this compound
Most developed test surrounded the precipitation of arsenic through oxidative and reductive processes
Marsh Test
1836, James MArsh, british chemist, published improved sensitive method for detection of arsenic. Sample placed in a flask w/ Zinc and sulfuric acid. Arsine gas forms and led through a drying tube to hard glass tube in which it is heated. Arsenic deposited as a “mirror” just beyond the heated area and on any cold surface held in the burning gas emanating from the jet. Antimony gives similar
Orfila
Known as the father of forensic toxicology
Arsenic was the poison
Created and refined techniques for the identification of arsenic
First Treatise
Best known for his role in the “:aFarge” arsenic poisioning case in France
Lafarge
convicted of killing husband with arsenic
notable because 1st person convicted on direct forensic tox and reported by daily news
Heavy Metals Reinsch test
Detect presence of various heavy metals in a biological sample:Arsenic, Bismuth, Antimony, Mercury
Developed in 1842 by German Hugo Reinsch to detect As and Hg
Strip of copper is placed in the suspected fluid which then acidifed with HCL and boiled
If arsenic is present in a gray deposit occurs on the copper
Deposits on heating is sublimated and forms crystalline layer
Metallic copper i strong acids will displace from solution elements below copper in the electrochemical series
Displaced metal deposits on copper discoloring the copper indicating a positive results
Reinsch Test postive findings
Observation: As:dull black, Bi:shiny black, Sb, purple, Hg:silver
Test is not entirely specific
Selenium and tellurium also give dark deposit
High concentration of sulfur may give a speckled appearance
Jean Stevais Stas
first effective method for extracting alkaloids from biological material
Identified nicotine used to kill Gustave Fougnies-by brother-in-law Count Hypolyte
Method modified several years later by Otto which produced purer extracts of alkaloids
Stas-Otto Method
Wormley
First American book Dedicated to poisons “The Micro Chemistry of Poisons”
Written in 1869
Became standard on the subject world-wide
Gutzheit
Developed a method for arsenic in 1879
Semi-quantitative test for arsenic involving precipitation
Piece of zinc and a little sulphuric acid are added to the suspected liquid
Boiled, filter paper saturated with silver nitrate and hold in the vapor
Turned yellow if arsenic was present
Gettler
Greatest legacy was the training and direction he gave to the future leaders in forensic toxicology
Irv Sunshine
Fred Reiders
Henry Friemuth
Widmark
described pharmacology of alcohol in mathematical terms
Widmark equation
helped establish clinical signs and symptoms to intoxication and BACs
delevolped microdifussion method for quant
Mellanby
Examined the relationship between BACs and intoxication
Harger
Invented drunk o meter in 1938
First stable breath-testing instrument to measure alcohol levels
Invention came at a time when alcohol was a major political issue
Air in balloon released into chem soln. alcohol in breath-chem chamged KMNO4
Greater the alcohol in breath greater color change
Levels of alcohol could be estimated by simple equation
Borkenstein
Began career w/ Indiana State Police in 1936
Invented Breathalyzer in 1954 and retired in 1958 as Captain in charge of Laboratory Services
Borkenstein et. al 1964 studied role of drinking driver in traffic accidents
Known as Grand rapids Study
Known worldwide for his contribution to the field of chem test and breath alcohol
Freimuth
special agent and analytical chemist at FBI headquarters
1944-toxicologist for state of Maryland’s office of the Chief Medical Examiner
