Which of the following routes of exposure involves penetrating the skin?

• A. Ingestion
• B. Injection
• C. Inhalation
• D. Absorption

Answer: (D)

The route of exposure that involves penetrating the skin is absorption. This process occurs when chemicals or hazardous materials enter the body through the skin or mucous membranes. When a substance is absorbed, it can bypass the digestive and respiratory systems, potentially allowing for quicker access to the bloodstream and tissues, which can lead to systemic effects.

Inhalation pertains to exposure through breathing, where airborne particles, gases, or vapors enter the respiratory system; ingestion refers to taking in substances through the mouth, often involving the gastrointestinal tract; and injection deals with substances being introduced directly into the body via a puncture, such as with a needle. While these other routes can also result in exposure to harmful substances, absorption is specifically related to the interaction with the skin.