Since there is talk about bringing back ASBESTOS (this is somehow true), I thought it would be useful to describe just…

Since there is talk about bringing back ASBESTOS (this is somehow true), I thought it would be useful to describe just some what happens to you when you breath this stuff into your lungs. In short, it’s terrible. A 🧵

What is asbestos? Asbestos is a group of naturally occurring fibrous minerals. There are 6 types: Chrysotile, Amosite, Crocidolite, Tremolite, Actinolite and Anthophyllite. They have some useful properties (including heat resistance, strength, durability and well insulating)

Because of these physical properties, humans have been using asbestos for thousands of years for a variety of purposes. In the 20th century, it began to be used as a building material. In the 1970s, the health risks associated with asbestos exposure began to be recognized.

Inhalation of asbestos fibers will directly damage your lungs. Over time, this can lead to conditions such as mesothelioma, lung cancer, and the appropriately named Asbestosis. But how?

Asbestos fibers are small (~0.1 to 10 microns in length). Due to their size, they are readily inhaled. Given their size, and how aerosol deposit, they can deposit anywhere in the respiratory system I discussed how aerosol deposits in the lungs in a video: youtu.be/qbIuqv8iECc

The respiratory system has various strategies to deal with inhaled particulates and pathogens. For example, cilia (tiny hairs in the airways) can move particles deposited in the mucous of the upper airways and transport them to the throat where they are swallowed, limiting harm.

Another tool the body uses are to protect the lungs are macrophages. Macrophages are white blood cells that engulf and digest pathogens that deposit in the lungs. They are great at fighting off bacteria infection, and will also engulf particulate air pollution.

Macrophages are ambitious cells, where they will try to engulf anything that deposits in the lungs that isn’t supposed to be there. For bacteria, this is fine since bacteria are small, organic balls of material that is readily engulfed and broken down.

Small particulates are less ideal as they don’t readily breakdown (at all). That said, they can still be engulfed by macrophages due to their small size.

Like particulate matter, asbestos can’t be processed by a macrophage. What makes asbestos unusually harmful is the fiber’s rod-like shape. Often, the rod is too long for a macrophage to fully engulf, leading to the macrophage being impaled.

The impaling of the macrophage is problematic for number of reasons. Firstly, it means that the fiber is not being readily removed from the lungs as the macrophage is not able to transport it. The fiber remains in the airway, further causing harm.

The damaged macrophage will then release intercellular signals, termed cytokines, that essentially call for help to deal with the problem. This triggers a chronic inflammatory response. I discussed how inflammation in the lungs leads problems in a video: youtu.be/idddJ-JsV_o

Along with inflammation (which alone is a huge problem!), the impaled macrophages will also stimulate fibroblasts. Fibroblasts are cells that synthesize extracellular matrix and collagen. They are critical in wound healing.

Fibroblasts are incredibly useful in the body as they play a major role in wound healing and tissue repair. That said, extensive wound healing (scarring) in the lungs that results from the inhalation of asbestos will lead to many problems. Namely, fibrosis.

The accumulation of scarring in the lungs leads to poor lung function. Repeated damage, followed by repair, leads to something called “airway remodeling”. Literally, the structure of the lung itself is altered leading to poor function.

Airways are thickened, mucous production is increased, the lining of the airway changes. In short, the lungs operate worse and worse.

Over time, the structure and function of the lungs will continue to deteriorate. Thickening walls will limit how well the airways are able to expand and draw in air. Thicker mucous layers will limit the rate in which oxygen and CO2 are passed back and forth from the bloodstream.

This will lead to a lower quality of life. Eventually, it could lead to more serious health problems such as lung cancer. Described in this thread is just some of the harm caused by this terrible material.

Lungs don’t recover, and the long-term damage is additive. Asbestos was banned for a reason. The adverse health effects resulting from exposure is horrific. If they end up bringing it back, I’d suggest stocking up on masks….