Routes of Exposure and Toxicity Tests

The major routes through which the toxic chemicals enter the body under normal workplace conditions are by inhalation (respiratory route), through skin absorption (dermal route), or through ingestion (oral route). Many chemicals are known to cause the most severe health effects and rapid responses to test chemicals as soon as they enter directly into the blood circulation of animals. Several routes are used to evaluate and determine the toxicity and safety of chemical substances using species of laboratory animals in experimental toxicology studies. These routes of exposure include  

Industrial workers and the general public are often and regularly exposed to a wide range of chemicals, depending upon the nature of work and workplace. Exposure to high concentrations of chemicals for a prolonged period causes health effects of different types  

Primary irritants cause local effects such as irritation to eyes, skin, nose, and mucous membranes, as well as skin rashes and dermatitis. 

Lung irritants cause irritation or damage to pulmonary tissue. 

Asphyxiants cause interference with or prevent the uptake and transformation of oxygen in the body. 

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