Team:Pasteur Paris/Safety
SAFETY FOR THE ENVIRONMENT
A major concern of our project is to prevent any risk for the environment and the human body. The genetically modified E.coli must not leave the biofilm because they could have unintended environmental or health consequences. In order to avoid collateral damage, we implemented two barriers to prevent the genetically modified bacteria to spread outside the biofilm.
The first barrier is a physical one: the biofilm is contained inside a membrane having small pores that the bacteria cannot pass because of its size. The biocompatible membrane made of aluminum oxide and covered by a polymer, have pores of 0.2 micrometers which is smaller than the size of the bacteria composing the biofilm. The second barrier is a biological one, that we integrated into the genetically modified E.coli forming the biofilm. Indeed, we worked on a kill switch that is cryosensitive. The bacteria should die when they leave the prosthesis and go in an environment that has a temperature lower than 37°C. In practice, the kill switch is fully effective when the temperature is lower than 22°C. The membrane and the kill switch confine the bacteria inside of our device, so they won’t spread inside the human body or the environment.
LAB SAFETY: A time line to understand the lab worker's daily life
A time line to understand the lab worker's daily life
This role-playing shows that, during one day as a lab worker, you may have to work in laboratories with different biosafety levels. Then, a classification exists which takes into consideration the organism used, the equipment practices and procedures you have to follow. Mainly, BSL-1 and BSL-2 are used for research. However, in some important cases, you could use BSL-3 lab and more. An important point is that rules are cumulative, it means that in BSL-2 you have to apply BSL-1 rules and BSL-2 rules.
BSL-1: a basic laboratory with a biosafety level 1
This laboratory is used for basic teaching and research. In this lab, you have to use good microbiological techniques (GMT). GMT rules should be applied every time you work with any microorganism, regardless the biosafety level. No safety equipment is required except an open bench work. No isolation of laboratory is required.
BSL-2: a basic laboratory with a biosafety level 2
This laboratory is used for primary health services, diagnostic services and research. As a BSL-1 lab, you have to adopt GMT practices but also wear protective clothing. In this lab, you will see the biohazard sign. With a bench work, in this lab, you must have a class II BSC: biological safety cabinet, a protection against potential aerosols. No isolation of laboratory is required.
BSL-3: the containment laboratory with a biosafety level 3
This laboratory is used for special diagnostic services and research. You must wear special clothing. This lab is controlled for its access, and has a directional airflow. As BSL-2 lab, this lab requires a class III BSC and other primary devices for special activities. Thus, isolation of laboratory is required.
BSL-4: the maximum containment laboratory with a biosafety level 4
This laboratory is a dangerous pathogen unit. In this lab, you have an airlock entry, a shower exit and special waste disposal. Safety equipment is composed of a class III BSC with a double ended autoclave. Moreover, the air is always filtered. Thus, isolation of laboratory is required.
In this lab, you must pay attention to personnel safety monitoring capability: indeed, you must have a closed-circuit television and a two-way communication for example.
REFERENCES
World Health Organization "Laboratory Biosafety Manual. Third Edition.", Geneva (2004),http://www.who.int/csr/resources/publications/biosafety/Biosafety7.pdf