Homework Assignment 1
Question 1: Explain the key difference between irritation and allergic contact dermatitis.
Contact dermatitis refers to a condition in which the skin becomes sore, red or inflamed after direct contact with a foreign substance. There are two types that include irritant and allergic contact dermatitis.
Irritant dermatitis occurs after a body comes into contact with acid or alkaline material. It can also be caused by other materials such as a soap detergent, fabric softeners, solvents and any other chemical that get into contact with the body. The irritation is usually confined to the specific area that the body came into contact with the irritant. Other possible irritant agents include hair dye, pesticide, shampoos and hair dyes.
Allergic contact dermatitis refers to a condition that occurs when the skin comes into contact with a substance that causes an allergic reaction. These include things like fabrics, soaps, fragrant, adhesives, antibiotics, and aftershaves among others. The reaction is not instantaneous and may take 24-48 before the symptoms appear. Some agents require a third agent such as sunlight for the reaction to occur (Marc et al.).
Question 2: What is systemic intoxication?
This refers to intoxication from substances whose impacts are not confined to one part/organ but rather spread to all parts of the body in different degrees. The major effects are manifested in a few organs. It generally refers to the spread and absorption of toxicants further into the body and away from the point of entry.
Question 3: Explain the difference between first, second and third degree burns.
The first degree burns appear red and are very painful. They swell a bit and appear white when pressure is exerted on them. The skin on the burn usually peels off after a few days. It is the least severe as it only affects the outmost layer of the skin (epidermis).
The second degree affects the outer layer of the skin and as well the thicker second layer of the skin (dermis)
The third degrees cause damages to all the skin layers. The damaged part appears white and charred. They are not very painful in some cases as the nerves are damaged and thus cannot sense the pain.
Question 4: Why are Hydrofluoric acid burns so dangerous? What happens if they go untreated?
Hydrofluoric acid is a contact toxic that is very corrosive. It is termed as weak owing to its properties of not dissociating fast. Therefore it penetrates the skin more rapidly and damages the tissues on the surface and inside the body. If not treated immediately, HF acid is absorbed through the skin and reacts with the blood calcium thus causing cardiac arrest. It also reacts with Mg2+ as well forming solid precipitates which are painful and toxic to the body (Hatzifotis, et al.).
Question 5: In each level of control (engineering, admin., PPE) How would you prevent skin exposure to Acetic Acid in a chemistry laboratory? Be specific and reference outside sources used.
Acetic acid penetrates the ordinary rubber gloves and thus a precaution will be to use double non latex gloves. In addition, a lab coat and goggles or face masks should be used to protect the face and other body parts. The room should be well ventilated (Hurum).
Question 6: Explain the difference between a chronic and an acute exposure and give an example.
Acute exposure refers to a less serious exposure that lasts only a short period of time or small quantities of ration over a long period. The exposure causes both delayed and immediate effects to the subjects. Chronic exposure refers to the exposure of large quantities of radiation and over unspecified timelines. In chronic exposure, there are usually delays lasting months or years before the symptoms can be detected. The reaction on the subject depends on the total radiation, time and rate of exposure and as well the organs that were exposed. Example of acute exposure include medical x-rays while chronic ones include severe exposures and poisonings caused by the atomic bombs like the one detonated in Hiroshima and Nagasaki during World War II.
Question 7: Define irritation
This refers to the state of inflammation or allergic reactions to allergy or to cell-linings. This is caused by materials such as nitrogen dioxide, hydrogen chloride and dusts among others.
Question 8: Explain the difference between a primary and secondary irritant
Secondary irritants cause irritation and intoxicate the membranes of the organs that comes into contact. Examples include Hydrogen Sulfide, Aromatic Hydrocarbons, and can cause severe damages including hemorrhage (William et al.).
Work Cited
Boone, Marc A., et al. "Differentiating allergic and irritant contact dermatitis by high-definition optical coherence tomography: a pilot study." Archives of Dermatological Research, vol. 307, no. 1, 2014, pp. 11-22.
Hatzifotis, M., et al. "Hydrofluoric acid burns." Burns, vol. 30, no. 2, 2004, pp. 156-159.
Hurum, Deanna. "Laboratory Safety Information for Students." UW Faculty Web Server, North Western University, faculty.washington.edu/korshin/Class-486/AEESP-safety-notes.pdf.
Luttrell, William E, et al. Toxicology Principles for the Industrial Hygienist. 2008.
