Personal safety is important in the lab to avoid injuries and contamination. Our instructors gave us important security guidelines at the beginning of the project. At least one instructor or advisor was present when we were at the lab to check that everything was okay with security. We could resume basic rules as follow:
Always wash your hands and disinfect your lab bench before and after each manipulation with ethanol. At the end of the benchwork session, hands need to be thoroughly washed and dried with paper towels.
Always wear appropriate clothes: lab coat, closed shoes, attached hair, no hand jewels, avoid wearing contact lenses...
Always be sure to work in appropriate conditions (i.e. under a fume hood if handling hazardous chemicals).
Always ask if in doubt !
A guideline book was provided, including descriptions and safety issues of chemicals we have to manipulate. It was important to refer to that before starting an experiment.
The project’s special safety
Our project has two major aspects about safety : chemical safety and biological safety. Because we did a lot of molecular biology and complex chemical reactions we were prone to use dangerous chemicals. They were systematically used under a fume hood, with nitrile gloves and goggles. Waste was discarded in a dedicated area with a tank for each kind of chemicals (organic solvents, acids, bases) and a tank for solids (eg agarose gels stained with ethidium bromide). Here is the list of the most hazardous compounds used:
Concentrated HCl and NaOH
BET and CYBR Green, in a dedicated room.
Glacial acetic acid
Biological experiments also require their own safety precautions. We only used K12 derivatives of E. coli, which is a risk group 1 bacterium that requires only basic precautions. Biohazardous waste was discarded in special cans and handle by an external company. Liquid waste was collected and autoclaved prior to disposal. Avoiding environmental contamination with modified strains is a key aspect when working with exogenous expression plasmids and strains. Working surfaces were systematically cleaned with ethanol. We worked with Bunsen burners to avoid air contamination of our cultures. Among the parts constructed by our team, genes coding for the reverse transcriptase of HIV 1 were used. These genes originate from a class 3 viral organism. However, we did not used the whole organism, but only recombinant proteins. The sequences were synthesized de novo by GeneCust, to avoid the manipulation of the whole HIV genome as a PCR template. Moreover, a construct using a gene coding for a surface protein from Hepatitis B was also designed and ordered from IDT. These two genes belong to human pathogens but are not pathogenic in their isolated version. To put it in a nutshell we followed fundamental rules of biological and chemical safety in a scientific laboratory.