Friendly laboratory advice from our resident superhero (technician by day, PhD student by night)
by Srinivas Rao – My relationship with chemicals, handling and characterizing by smelling strong, pungent, fishy, phenolic, or sweet almond odors, began in my Class 11, right after matriculation.
We, the students, were always curious in the lab to smell each and every chemical, even though they may be toxic ! Some odors in the lab smell like Banana (isoamyl acetate), Lemon (citral), Orange (limonene), vanilla (vanillin), Fishy (Pyridine), or fruity/nail polish remover (Acetone). We liked the smell of a few chemicals; sometimes they were stinky like hydrogen sulphide or ammonia.
We were always mischievous, and instinctively used to smell compounds during our first few days in the chemistry lab. Teachers, lab instructors had to incessantly remind us to stop from doing this since many organic compounds are toxic or at least irritating.
The focus of this blog is taking precaution on the usage and storage of chemicals.
Reports of accidents and incidents involving the use and contamination of chemicals are far too frequent aren’t they? We must remain careful in properly handling, using and storing these hazardous chemicals, or problems will arise.
Before we start working with chemicals, we need to make sure we have the proper Personal Protective Equipments (PPE). At a minimum, this should include appropriate chemically-resistant gloves, eye protection, closed-toe shoes, and lab coats. Always make sure emergency exits and equipment areas i.e., eyewash are clear and free of stored materials.
Whenever we deal with chemicals, there is a risk of spillage on hands. The second most common route by which occupational chemicals enter the body is our skin, first being inhalation. Chemicals which pass through the skin are nearly always in liquid form. Solid chemicals and gases or vapours do not generally pass through the skin unless they are first dissolved in moisture on the skin’s surface. Chemicals can also enter through cuts, punctures or scrapes of the skin since these are breaks in the protective layer. Contact with some chemicals such as organic solvents can cause skin dryness and cracking. There can also be ulcerations or skin flaking. All these conditions weaken the protective layer of the skin and may allow chemicals to enter the body.
One of the simplest ways to reduce the amount of waste is: take no more chemical than you need from the original container. Once you have removed a chemical from its original container, it must be considered contaminated and should not be returned to the container.
If not, the reagent must be properly disposed off. Do not leave excess chemicals lying around near balances or hoods or elsewhere in the laboratory. Also, to minimize contamination as well as unpleasant odors, put the lids/caps back on all original stock containers immediately.
The Material Safety Data Sheet (MSDS) is a document that must be glanced at for all hazardous chemicals before use. It provides useful information on chemical hazards, advice on safe handling, use and storage, and the emergency measures to be followed in case of an accident.
A considerable part of the work in a chemistry laboratory involves using chemicals and processes that can be dangerous if not properly handled. With careful preparation beforehand and careful use of chemicals and equipment, accidents can be avoided. Lack of intelligent preparation and careless use of chemicals and equipment can be extremely hazardous, even fatal.
As it is said over and over again, chemical safety begins with a good working knowledge of the chemicals you use and their hazardous properties.