Dermal Absorption

According to the CDC more than 13 million workers in the US are exposed to chemicals that are able to absorb through the skin.  With that being said, our skin is our body’s largest organ and acts as a barrier to prevent substances from getting in. Our skin is designed to protect us from external harms. Dermal absorption is “the transport of chemicals from the outer surface of the skin in.”  Dermal absorption is an extremely important area of matter because we are constantly coming in contact with different substances that could have an effect on our health.   

Dermal absorption can take place in occupational, environmental, and through consumer skin exposure such as cosmetics and pharmaceutical products including dermal ointments. Other exposures to substances or chemicals include using nail polish remover, cleaning supplies, and even the foods we eat.

If your profession is working and dealing with dangerous chemicals on a daily basis there are preventative measures that can be taken to reduce the risk of dermal exposure. Personal protective equipment is often used however you should not only rely on the PPE because there is always a possibility of exposure. If a chemical breakthrough occurs while wearing PPE the substances can become caught against the skin, leading to a higher rate of absorption in comparison to uncovered skin. Risks that can occur in different occupational settings if exposed to chemicals through dermal absorption include, skin infections, skin cancer, and irritant contact dermatitis.

Occasionally, individuals who have been exposed to dermal absorption go without noticing. With this being said, dermal exposure can lead to a systematic transfer, which is when the chemical enters ones bloodstream. This can be extremely dangerous and can cause health complications that are away from the site of entry.

Our skin is comprised of two layers, the epidermis and the dermis. The outer layer of the epidermis id composed of a compacted layer of dead epidermal cells called the stratum corneum acts as a barrier and is largely responsible for the rate at which dermal absorption occurs.  Chemical absorption through the stratum corneum occurs by a “passive process in which chemicals diffuses through thisdead skin barrier.” There are three ways in which chemicals can be diffused into the skin. These mechanisms are intercellular lipids, transcellular permeation and through the appendages. Firstly, the intercellular lipid pathway “consists of cells known as corneocytes.” The spaces between the cells are filled with lipids that include fats, oils and or waxes, chemicals can pierce through the lipids. Transcellular permeation is when particles diffuse straight through the corneocytes. Lastly, the third pathway for chemical entry into the skin is through skin appendages. This pathway is not as significant as the others.

 

There are factors that play a role in the rate of exposure which include, if your skin has any abrasions, the amount of time that one was exposed to a substance, the concentration of the chemical that was exposed to the skin and the condition that your skin is in. One important thing to note is that everything that is absorbed is a risk but not always harmful. An example of this would be cosmetics applied to ones face. Our bodies filter out water and molecules, getting rid of what does not belong by excretion through bodily fluids.