Laboratory chemicals are found commonly as solids, powders, gases, fumes and liquids. Your body is vulnerable to harm through exposure to chemicals when you work in laboratories. The extent of harm can depend on the level of exposure and individual tolerances to allergic reactions of such materials.
In your school days a lab coat was considered sufficient protection as such exposure was limited to a small range of chemicals and reagents. However, as you moved from school laboratory to college laboratory to research or industrial laboratory so did the exposure increase to a wider range of chemicals having greater potential hazards and toxicities. It is important for you to have awareness of the routes that chemicals can take to enter your body so that you can take required preventive measures.
Basically there are four basic entry routes:
- Skin or eye contact
- Oral ingestion
The article briefly discusses how the chemicals take the entry routes:
Skin or eye contact
Skin is a natural barrier which prevents you from the harmful effects of chemicals. Liquids or dissolved solids or powders dissolved in naturally occurring moisture on the skin can gain easy access into different layers of the skin and find their way into the bloodstream. Solids or gases unless soluble in liquids are seldom able to penetrate the skin layers. Some chemicals due to their corrosive nature cause instantaneous burns and wounds on skin. The damage can be serious if such exposure is left unattended
Eye contact generally occurs on account of splashes caused by violent reactions or when making the mistake of diluting strong acids by adding water to them. No doubt corrosive acids can cause burn injuries but milder chemicals can enter the blood veins through exposure through fine blood vessels of the eye. However, in any case, immediate remedial measures are needed to be taken to prevent damage to the eyesight.
Inhalation is another common entry route of laboratory chemicals into your body. Laboratory can present several sources of inhalation such as gases, solvent vapours, corrosive or toxic fumes or suspended particulate matter. Though the respiratory system has several defense mechanisms such as nasal hair and mucus in respiratory airways but still such vapours or solid particles do manage to reach the lungs and lodge into the bloodstream through absorption by blood vessels in the lungs. On the other hand strongly corrosive vapours and fumes can cause burn injuries in the respiratory tracts.
It would indeed be rare for anyone to intentionally swallow the laboratory chemicals for the sake of tasting them. However, danger exists through consumption of contaminated foods and drinks in laboratories. On reaching the stomach such chemicals enter the blood stream through blood vessels of the stomach lining or the finger like projections of small intestine. However, fortunately the unabsorbed chemicals get excreted without causing further damage.
Injection of chemicals commonly takes place through accidental exposure such as carelessness in handling injection syringes and needles or through careless handling of broken bits of contaminated laboratory glassware or other laboratory sharps. Such fragments need extreme care in handling and disposal.
The present article covered the routes of entry of chemicals into the human body. A subsequent article will cover the measures that should be adopted to prevent harm from such ingested laboratory chemicals.