Ingestion is entry through the mouth. It is not a major concern in an industrial setting. However, the key concern is that employee's food and hands might come in contact with a toxic substance and as a result the substance would be ingested. If the amount of toxic chemical that enters the body through ingestion is low, the liver may be able to convert it to a nontoxic substance or decrease the level of toxicity. Some substances pass through the kidneys and can be eliminated in the urine.
Injection involves introducing a substance into the body using a needle and syringe.
Consequently, this is not often a route of entry for a toxic substance in the workplace. Chronic effects are long term and persistent effects of chemical exposure. Chronic effects result from repeated exposures over many years, which are permanent and irreversible. Irregular heart beat, upset stomach, kidney pains, jaundice Kidney, heart or liver failure, leukemia, sterility, birth defects, impotence, cancer Table 1. Ventilation Useful for airborne contaminants.