How Chemicals Enter the Body

As you use or come into contact with chemicals, be aware that they can enter your body through four major routes.

  • Inhalation – gases and airborne particulate can be breathed in through your nose or mouth.
  • Absorption – chemicals, including dust, smoke or vapors, can enter your body through your skin or eyes.
  • Ingestion – chemicals can enter your body through your mouth.
  • Injection – chemicals can enter your body through an accidental impact, cut or puncture to your skin.

Here's how these chemicals can enter your body, and what preventive measures are available:

Inhalation involves airborne contaminants that can be inhaled directly into the lungs through the nose or mouth. These contaminants include dusts, mists, fumes, vapors and gas.

Inhalation is the most common route of entry a chemical can take to enter the body.

Prevention - Personal protective equipment that provides protection from airborne contaminants includes respirators or masks appropriate for the specific contaminant.

Absorption involves hazardous chemicals that are absorbed through direct contact with the skin or eyes. These chemicals can include particulates (dust, smoke), liquids, gases and vapors.

Prevention - Absorption through the skin and eyes can be prevented with the use of appropriately selected gowns, gloves, work clothing, personal protective equipment that covers the eyes, such as full face masks, safety glasses with side shields, and face shields, appropriate for the specific contaminants. In some instances a hazard suit with full head mask is appropriate.

Ingestion involves hazardous chemicals that enter the body through the mouth. These include chemical dusts, particles and mists that are inhaled through the mouth and swallowed or which have contaminated objects, such as hands, food and cigarettes, that come in contact with the mouth.

Prevention - Good hygiene practices are important in preventing products from being ingested. In areas where harmful chemicals are handled, eating and smoking should not be allowed. In this situation careful and thorough hand and face washing is required before eating and at the end of every shift. Inhaled toxic dusts can also be ingested in amounts that may cause trouble. In these situations, appropriate barriers, such as dust masks, are necessary.

Injection may occur through the misuse of syringe needles or through accidents with broken glass or other sharp objects that have been contaminated with chemicals. Injections can also occur through high pressure streams of liquids or gases.

Injection is not a common route of entry.

Prevention - Cautious use of any sharp object is important. Know proper storage, handling and disposal procedures when using syringe needles, glassware or other potentially sharp objects. Wearing gloves and other protective clothing may also reduce the possibility of injection.