Air Sampling (benzene)

            The average adult breathes in around 11,000 liters of air every day. With each breath, air travels through the respiratory system. The respiratory system is very complex. It can get damaged from the things in the air that we inhale.  To understand how clean the air is and what is in it we sample it. Sampling is used to monitor the air, researchers also use it to study what particles are in the air. Hundreds of particles can be in the air at any given time. These particles vary depending on where you live. Air pollution from factories and car emissions are particles that you do not want to breath. A few of these particles are okay, but not a large amount. A large amount will cause damage to your respiratory system. Sampling the air will let us know if the area has good clean air or not. There are many techniques you can use to sample the air. An air sampling device must be properly calibrated before using it. If it is not calibrated you will get results that are wrong and you will not be able to use the data. Before using the pump, you need to make sure it is fully charged. After turning on the pump you should run it for 10 minutes, because when you first take it off the charger the batteries might cause a sudden surge at the beginning. Also, making sure you take the sample in slow enough is very important.

            When collecting an air sample, you need to do it over an 8-hour time period. Each hour could have different readings. Many people work an 8-hour shift, collecting samples that they are exposed to over their work day is very important. This will see if the employees are safe during the work day. A worker that is exposed to polluted air 8 hours a day 5 days a week is going to have health problems. Air quality numbers are set to limits to ensure worker safety. Standards are set through OSHA. It is the law that employers provide employees with safe working conditions. For each chemical or particle, a number range is issued about what is safe and what is not. Flow rate is determined by volume as it passes through an area per time. To test the air that you are collecting sample bags are used. The bag hooks onto the pump and the collected air flows into the bag. The bag is then sent to the lab. When a good sample is collected without any errors it is a stable sample. Around 2-3 blank samples will be taken. Blank samples are air samples that do not run through the air pump. These blanks let the lab know what was already in the air. The sample that we took in class was 2 liters per minute. This is a safe sample of benzene. The parts per million is .75 and anything under 1 is considered safe. This sample that was collected is classified as being safe for employees to work in. 

AIrborne hazards

            The body is a complex system and works in a very particular way. The respiratory track is one part of the body and consists of the nasal cavity, soft palate, larynx, trachea, bronchi, and lungs. Air enters through our mouth or nose travels down our trachea and goes to our lungs.  As we breathe in air our diaphragm tightens to increase the space in our chest cavity to allow the lungs to expand. Right before the air goes to the lungs they enter the bronchi and then to the alveoli. Once the air reaches the lungs the oxygen it provides, then goes to the bloodstream. Foreign particles can get into the respiratory tack and cause major problems. The body has a few barriers so this does not happen. A few barriers are mucus, nasal hairs and cilia. Mucus and cilia line the lungs and catch bacteria and foreign pathogens that enter the lungs. This mucus is very sticky and the foreign particles get stuck in it.  This is called the mucociliary elevator, the goal is to get bad particles stuck and then get them out of the body. When these particles get stuck in the mucus humans cough it up to get rid of it. Another way of getting rid of the harmful bacteria is swallowing it into the stomach. The stomach acid will then destroy these bacteria.

            Airborne hazardous come in different classes and sizes. Some hazardous are more toxic than others. One hazard comes from dust. Many dry particles occur on their own. Dust is also produced in physical processes like in a factory. Inhaling dust has many side effects including irritation in the respiratory track, and allergic responses. If exposed for extended amounts of time it can lead to severe lung diseases. A second hazard is mites, which are airborne droplets. The droplets come off liquids. Side effects include inflammation of mucus production and fluid in the lungs. A third hazard is through fumes. Fumes are produced when materials are heated hot enough that they become a vapor gas. Gases are also an airborne hazard and are very common. A mix of gases can become lethal very quickly.  Breathing in a gas for a few seconds could make you pass out and die. Vapors are closely related to gasses. They are a gaseous phase of liquids. These different airborne hazardous come in different sizes, the larger the particle the more likely your body will be able to get rid of it. If the particle is small it can sneak by your defense mechanisms and enter your body. Your airway can become obstructed. If the airway is obstructed air cannot move, the airway is blocked. The airway can become blocked if a foreign object gets stuck or an allergic reaction occurs. During an allergic reaction, the airway can swell shut. A restriction in the airway can also happen. A restriction is not as severe as an obstruction. A restriction will decrease the air flow to and from the lungs due to swelling. The swelling is not blocking all of the airway, just part of it.

Toxicology

        Toxicology is the study of chemicals in or on an organism and how they are affected by these chemicals. It is very vital to know different levels of exposure to different things and to find out what is safe for humans and what is not. Their are many different ways these chemicals can get into the body. These chemicals are everywhere, small amounts do not usually harm people but large amounts can. A very strong chemical could injure you with just a small amount. One route of entry is inhaling chemicals into the lungs. It is one of the more common routes of entry into the body in a lab setting. It is very dangerous when chemicals get into the lungs. To get to the lungs the chemical also passes through the mouth and throat. Once the chemical is in the lungs it gets into the mucus membrane and makes it difficult to breathe. Another route of exposure is absorption through the skin. Different types of chemicals can burn you if you touch them. A chemical could also give you a bad rash. You can protect yourself by wearing gloves when dealing with harmful chemicals to limit exposure to the skin. Many bottles with chemicals have if it is safe or not somewhere on the bottle. The last two exposures are injection and ingestion. In a hospital setting many types of needles are used, if you were to get poked by a used needle you are now at risk. The needled that poked you could contain a number of diseases which could now get passed on to you. Drug users who use needles are also at a very high risk of exposure when they use dirty or used needles.  Ingestion would be eating something that is toxic or poisonous to humans. Many plants exist around the world and researching or knowing which ones are safe to eat are very important. One bite of a lethal plant could kill you.

      Biotransformation is what the body does when a drug enters the body. The ideal goal is to get the chemical out of the body or to break it down. The body deals with the drug many different ways. One way is a phase 1 reaction. This reaction converts a drug to become more water soluble with active metabolites. Drugs that are metabolized like this have longer half lives. Phase 2 reactions also make the drug more water soluble but have inactive metabolites. Dose response is a very important aspect in toxicology. Dose response is the change in a organism based off of different levels they were exposed to. If the dose was large the organism is going to have more problems. This occurs after a certain exposure time, each chemical is different. Each chemical has a point where it becomes unsafe. Other factors also contribute to this including weight and height. If a larger person and a smaller person got exposed to the same amount of chemical, the smaller person is going to be affected more. Ld50 is the median dose of exposure where half of those who were exposed died and the other half lived. This helps us understand what dose is lethal to humans.