Final answer:
The main routes for chemicals to enter the body are inhalation, ingestion, and contact with the skin or eyes. Each route can lead to different health problems, including long-term effects from substances such as arsenic in drinking water or acute reactions from hazardous household products.
Step-by-step explanation:
The main exposure routes for chemicals to enter the body are through inhalation, ingestion, and skin or eye contact. When chemicals are inhaled, they can be absorbed by the lungs into the bloodstream and reach internal organs.
Ingestion occurs when chemicals are swallowed, either accidentally or through consumption of contaminated food or water. This leads to absorption in the digestive tract. Skin or eye contact can result in chemicals being absorbed through the skin into the bloodstream or cause local damage.
Different job functions, like spraying operations, can lead to varying levels of exposure, often involving the skin and respiratory system. Furthermore, pharmaceutical residues can reach the environment through excretion from patients, with a fraction not taken up into the bloodstream being excreted and potentially contaminating water systems.
For a pathogen to cause disease, it must enter the body through a portal of entry. Major portals include the skin, mucous membranes, and routes bypassing the skin directly, like injections (parenteral routes).
Chemicals such as arsenic can be found in drinking water, leading to long-term exposure. Strong household chemicals can cause poisoning through ingestion or skin contact, highlighting the importance of understanding exposure routes to prevent accidental harm.