Q.E 19

• Burning (direct) – the principal damage due to flame and muzzle blast is more visible than to the penetration of bullet.
• Singeing (1 to 2 inches) – slightly burnin
• Smudging – produced when the gun is held from about 2 inches to the maximum of 8 inches
• Tattooing (8 to 18 inches) – (Black coarsely peppered pattern). Individual specks of tattooing around the hole are visible

  by the naked eye
• Harrison-Gilroy – test for the presence of lead, antimony and barium
• Sodium Rhodizonate Griess Test – test for the presence of nitrates.
• Lucas Test – a characteristic smell that decreases in intensity with lapse of time and is observable immediately after

  firing.
• Hydrogen sulfide – another product of combusting gunpowder and is present in the gaseous state that can be detected

  by means of a lead acetate paper.
• Rusting – as a rule does not commence for several days.
• Presence of nitrates – diminishes after a lapse of time
• Toxicology – the scientific study of the nature, properties and effects on living organism and detection of poisons and

  the treatment of poisoning.
• Paracelcus (16th century) – German-Swiss physician/ alchemist and Father of Modern Toxicology
• Descriptive Toxicology – involves toxicity testing of chemicals providing information for safety evaluation and regulatory

  requirements.
• Mechanistic Toxicology – concerns with identifying and understanding mechanisms by which chemicals exert toxic

  effects on living organism.
• Regulatory Toxicology – involves in decisions, based on data provided by descriptive and mechanistic toxicology,

  whether a chemical poses a sufficiency low risk capable for consumers for stated purposes.
• Forensic Toxicology – concerns primarily with the medico-legal aspects of the harmful effects of chemicals on human

  and animals
• Clinical Toxicology – concerns with disease caused by or uniquely associated with toxic substances.
• Environmental Toxicology – focused on the impacts of the chemical pollutants in the environment on biological

  organisms.
• Occupational Toxicology – study of the adverse effects of agents that may be encountered by workers during the course

  of their employment
• Risk – the potential likehood that injury will occur in a given situation