SPECIAL PAPER – Environmental Toxicology I

History and Scope of Toxicology

Principles of Toxicology

·         Different Areas of Toxicology

·         Classification of Toxic Agent

·         Spectrum of Undesired Effects

Interaction of Chemicals

·         Additive

·         Synergistics

·         Potentiation

·         Antagonism

Dose Response

·         Individual or Graded

·         Response Relationships

·         Quantal Dose

·         Dose Response Curves

Variation in Toxic Responses

·         Selective Toxicity

·         Species Differences

·         Individual Differences

Animal Toxicity Tests

·         Acute

·         Subacute

·         Subchronic

·         Chronic

·         Development and Reproductive Toxicology

·         Mutagenicity

Skin and Eye Irritation

Mechanisms of Toxicity

·         Delivery

·         Absorption

·         Distribution

·         Excretion

·         Cellular Dysfunctions and resultant toxicities

·         Repair or Dysrepair

Biotransformation of Xenobiotics

·         Phase I Enzymes (Hydrolysis, Reduction, Oxidation

·         Phase II Enzyme Reactions (Glucuronidation, Sulfation, Methylation, Acelylation, Amino-acid conjugation Glutathione Conjugation, Phosphorylation)

Risk Assessment

·         Hazard Identifications (Assessing Toxicity of Chemicals)

·         Risk Characterization

·         Risk Perception & comparative Analysis of Risk

Environmental Impact Assessment

Specific Responses of Toxicity

·         Carcionogenesis

·         Mutagenecity (Genetic Toxicology)

Teratogenecity (Development Toxicity)

Target Organ Toxicity

·         Liver

·         Kidney

·         Nervous System

Blood

Physicochemical nature & Effect of Toxic Agents

• Pesticides: (General account )Organochlorine Compound, Antocholinesterase agents and pyrethroids esters
• Metals (Arsenic,Lead, Mercury)
• Industrial Solvents(General account)
• Radiation & Radioactive materials