Airborne Hazards

AIRBORNE HAZARDS ARE ALL AROUND US

Whether it's occupational, by choice, or a matter of circumstance from the environment we live in, we are all exposed to airborne hazards daily. Some may be more detrimental to our health than others, but it is pose for concern and discussion as to how dangerous this hazards really are and by what mechanisms they impact our health. Various factors that will be discussed are: 1) how the size of the containment impacts our bodies, 2) the locations of the respiratory tract infected, and 3) the mechanisms in which our bodies attempt to cleanse or rid the hazards. There are state and federal regulations that protect us all and provide us the rights to work in a safe and hazard free environment!

AIRBORNE HAZARDOUS MATERIALS BY SIZE

There are five major airborne hazard categories that are classified by size. They are as follows:

• Vapors (gaseous phase of liquids)
• Dust (aerosals composed of dry particles)
• Gases (most common airborne contaminate)
• Fumes (materials heated to a point where they become a gas)
• Mists (airborne droplets)

REGIONS OF RESPIRATORY TRACT

Regions of the respiratory tract all influence various different components of our air quality and the hazards that are encompassed within them. The regions are: inhalable fraction (known as the nasopharyngeal region (NP); thoracic fraction (known as the tracheobronchial region (TB); and the respirable fraction (known as the pulmonary region). Our nasopharyngeal region is essentially the region that intakes almost 100% of all of our environmental air and along with it, potential hazards. Where the contaminants travel down to, is dependent upon the size and other factors. 

MUCOCILIARY ELEVATOR

The mucociliary elevator is an internal mechanism within the respiratory tract, that acts as a protection barrier from foreign invaders. The thick sticky mucous lining traps pathogens and other particles inhaled and the cilia move in a rhythmic fashion to expel the contaminates out of the body. This process is constant and involuntary. Cilia projections are continuously moving and beating. 

RESTRICTIVE VERSUS OBSTRUCTIVE LUNG IMPAIRMENT

Restrictive impairment within the lungs refers to a reduction with the air volume. It influences how much air can be inhaled and exhaled. An example of this could be hardening of the muscles surrounding the outside of the lungs that become rigid and less flexible. Obstructive lung impairment however, involved the small airways (or bronchioles) and damage to those entry ways. The lung volume (vital capacity) itself has not been altered, it is the airways that are obstructed or impaired. A very common example of this is individuals who suffer from asthma. 

In many of the pictures depicted above, there are example of military personnel or Veteran Affairs initiatives involved open burn pits and airborne hazards. This is just one major example in our society where men and women each day have risked their lives and continue to, in harsh, dangerous, and lethal environmental conditions. Often times, we advocate for some of the major hurdles in our paths that are often the one's seen. However, airborne hazards are usually invisible and taken for granted daily and they may in turn, be the most deadly. 

Toxicology: Everything and Anything Can Be Toxic

Most of time, we can quickly think about things that are harmful or dangerous to our health. Common items such as poison, chemicals, radiation, or even a toxic relationship and people. We can illustrate toxicity within all aspects of our lives. But when we think of water, food, or other natural sources that we need for survival, how can those things be toxic? Let's find out! 

WHAT IS TOXICOLOGY?

CSI or Forensic Files images often run through our minds when we think toxicology. Toxicology is a broad range area of science that analyzes nature, and adverse effects of chemical substances on living organisms. Additionally, toxicology studies detection of poisons and may be associated with the autopsy process in the event of a homicide or overdose (e.g., which is often the prime example illustrated in CSI). In the event that a substance has caused harm to a living organism, toxicologists and other health professionals, first want to find out how the individual was exposed, and how it entered the body. 

ROUTES OF ENTRY INTO THE BODY

Below are the most common routes of entry (i.e. occupational) into the body that cause toxic exposure:

• Inhalation
• Absorption
• Ingestion
• Injection (aka "sharps" needles, contamination with bodily fluids, etc)

BIOTRANSFORMATION PHASE I & II

Biotransformation is a fancy word for the alteration process of a chemical or drug within the body. This process is split up into two categories: the metabolism phase (I), and the conjugation phase (II).

Phase I is the addition or exposure of a chemical to functional groups and begins the metabolism phase. Three main chemical reactions can occur here: 1) hydrolysis, 2) oxidation, and 3) reduction. 

Phase II is where detoxification occurs within the body. 

So, we've talked about predominantly chemicals and substances that are clearly harmful to a living organism, regardless of the amount or frequency of exposure. So, then, how can we claim that everything can be toxic, including substances us humans are made up of? We are about to find out! 

WHAT IS DOSE-RESPONSE?

Does-Response refers to the relationship of exposure degree and the magnitude of the effect. The degree of exposure is the dose and the effect magnitude is the response. This is often illustrated in mortality percentage rate. You van view mortality rates for the United States here. 

I've been referring the the element of water. For example, if a person is submerged under a large body of water, then they will be exposed to a large dose amount of that element. Therefore, if unable to breathe in oxygen for a period of time, the response will be the individual will drown. That is an example of how water is toxic to a living organism. 

WHAT IS LD(50)?

LD50 is a benchmark used in toxicology. This refers to the dose of a chemical needed to produce death in 50% of the population given. This factor helps determine if action is needed within a population or area that may have a severe medical emergency or exposure.

WHAT FACTORS INFLUENCE TOXICOLOGY?

So, all in all, we may be wondering by now: so why should I care? While many of us may not come into direct contact with a clearly toxic chemical on a daily basis, we all do have many things in common. We are all breathing beings. We inhale and exhale every second of the day and whatever is in our environment, we are exposed to and potentially at risk for. Additionally, we all use products that are needed for hygiene and other necessities (i.e., paper products, toothpaste, hand soap, detergent, etc.). These products as well are in fact toxic. 

Some factors that influence toxicology are: 

• Concentration
• Route of entry
• Acute versus Chronic exposure (e.g., duration and frequency time)
• Environmental factors
• Chemical combinations
• Intraspecies variations
• Interspecies differences (e.g., dogs versus cats)

We are all impacted by toxic substances every day. The more we know and can educate ourselves and the community around us the healthier we can be!