Laboratory Safety Concerns

Bacterial Strains Used

In order to minimize the working risk as much as possible, the iGEM Team Braunschweig 2014 exclusively worked with non-pathogenic organisms classified as risk group S1.

Safety equipment

The lab was standardly provided with safety equipment according to the S1 safety forms. Safety showers, eye showers, fire-extinguishers and a fire blanket were installed and easily accessible. Furthermore, lab coats, safety gloves and goggles were available at any time in the lab. Specially labelled areas were restricted to working with carcinogenic substances such as ethidium bromide.

Personal safety

Before starting any work in the wetlab every team member had to be given an instruction concerning health and safety. Additionally there was a tour of our own and adjacent labs with a supervisor. Instructions were given by a supervisor when using new equipment and techniques. Hazardous and carcinogenic chemicals and substances were avoided whenever possible. In this case these chemicals could not be substituted, safety equipment such as special gloves were used. Furthermore, to prevent any risk, the team members worked exclusively in groups of at least two members.

Sterile Work

To keep our lab sterile, working spaces and necessary equipment were cleaned with 70 % ethanol. Ethanol is easily flammable and was therefore used carefully and only for small areas. To avoid contamination of our cultures and for selection, antibiotics were added to the used media with the note that they can cause health problems in large amounts. Furthermore, they can cause undesirable resistances in bacteria and thus were used only if necessary. Ethidium bromide was used for gel electrophoresis with special care because of its DNA-intercalating and cancerogenic properties. Use of UV-light was necessary for visualization of DNA in agarose gels.

Bioethics

Bioethics was a very important topic for the team. Working with bacteria as chassis for recombinant protein production is common in science and generally accepted in society. Therefore, no bioethical questions were expected to arise in this matter. In case our project is turned into reality and cows are provided with our E. cowli strain we expect a lot of bioethical questions from the public. People are expected to react sceptically due to our planned use of recombinant organisms in animals intended for food production, which, in fact, is reasonable. The work on animals probably has to be handled in a more sensitive way than the work on other, simpler organisms such as bacteria. It has to be questioned whether the advantages for climate change resulting from the use of E. cowli can compensate the risk every recombinant organism brings up in the environment. Alternatively we planned to design a barn filter provided with a methane filter system based on E. cowli. This technology would render it possible to decrease methane emission without providing animals directly with a recombinant organism. Therefore, ethical problems are minimised as well.

Environmental Impacts

In case our project will be realized in cows, it is necessary to reconsider every possible risk recombinant organisms bring to nature and environment. Although there is no possible use of our project regarding national issues and although no toxins or pathogenic substances are expressed, it would be important to question as many risks as possible. Under these circumstances E. cowli will be justifiable due to the positive impact on the minimisation of climate change coming along with it. Additionally, construction of a kill switch is planned in order to avoid any possible risk in case E. cowli escapes into the environment. Furthermore, the application of E. cowli as a part of a barn filter system prevents every risk of its integration into the cow's rumen.

Working with Methane

Many laboratory operations require the use of compressed gases, so did the activity analysis of our enzyme sMMO. Compressed gases represent a universal and unique hazard. Besides the potential exposure to chemical and mechanical hazards dependent on the type of gas, the storage in heavy, highly pressurized metal containers represent another high risk-factor. The large amount of potential energy resulting from compression of the gas makes the cylinder a potential rocket or fragmentation bomb.
Due to the fact that we had to use methane during the experiments with Methylococcus capsulatus and our transformed E. cowli various security aspects had to be considered. Since methane is a flammable gas which, when mixed with air in a certain ratio, is also explosive we took the following safety precautions:
The setup was exclusively handled with the correct ratio of methane, air and carbon dioxide under a hood without power sockets or other potential sources of electrical sparks or fire. All experiments were conducted at methane-air-ratios under 5 % (Lower Explosive or Flammable Limit LEL/LFL) and over 15 % (Upper Explosive or Flammable Limit UEL/UFL) to eliminate the risk of a combustible atmosphere. Hence, we accepted suboptimal conditions for the purpose of safety concerns. Gas cylinders were stored according to the manufacturer’s instructions and closed completely when no experiment was running. Before using the respective gas for creating the needed ratio the system pressure of each cylinder was set to 1 bar. All equipment, including flow controllers, tubes and valves were screened for leak tightness regularly and their suitability for the used gas pressures. Find the safety data sheet of the supplier here.