hniques to detect the presence ofsubstances in the victim, in the suspected criminal, or at the crime scene. For example, indetermining whether alcohol was involved in a crime, the amount of alcohol in the blood can bemeasured in two ways.
One is to measure the amount of alcohol exhaled in the breath of anindividual, which reveals the concentration of alcohol in the person’s blood. Recent advancesin technology have produced alcohol breath-testing instruments so accurate that their resultsare evidential (capable of providing evidence in court). Blood-alcohol level can also bedetermined by actual blood tests, usually through gas chromatography. In this method, theblood sample is vaporized by high temperature, and the gas is then sent through a column thatseparates the various chemical compounds present in the blood. Gas chromatography permitsthe detection not only of alcohol but also of other drugs, such as barbiturates, cocaine,amphetamines, and heroin. 1The single greatest cause of accidents in the United States is the automobile.
In 1913 theAmerican industrialist Henry Ford introduced assembly-line techniques in the manufacture ofmotor vehicles. The subsequent increase in the number of automobiles in use was huge andled to a great rise in the motor-vehicle accident rate. In 1991 in the U. S. , automobile accidentswere responsible for about 49.
4 percent of all accidental deaths, as compared with accidentsin the home (about 23. 3 percent); accidents in public places, including railroads and airplanes(about 20. 5 percent); and work-related accidents (about 11. 3 percent). The second greatestcause of accidental deaths is falls, which account for some 13. 9 percent of all fatalities.
Accidental deaths reached a high of 110,000 in 1936, with a death rate of 85. 9 per 100,000. In1991 the total was estimated at 88,000, with a death rate of 34.9 per 100,000; this was thelowest accidental death toll since 1924 (85,600).2 .
