Difference between revisions of "Team:HebrewU/Safety"

Safety

This year, the Hebrew University of Jerusalem is taking part in the iGEM competition for the first time in its history. From our single bench in our PI’s lab we can work at a maximum capacity of two students at a time; however, every single student on our team, even those who did not set a foot inside the lab, received safety training as performed by all graduate students and lab technicians in the university.

The majority of our lab work included tasks such as Gibson Assembly, PCR, and the restriction, ligation and transformation of microorganisms (E. Coli, Agrobacterium, yeasts) as well as Arabidopsis plants – which do not have associated risks or health hazards to humans and are safe processes in general, with two exceptions. First is the sterilization of Arabidopsis seeds with chlorine gas. Acute chlorine gas poisoning in humans can cause symptoms that are primarily respiratory. There may also be skin and eye irritation or chemical burns with external exposure. Other symptoms may include nausea, vomiting, and headaches. The second risk involves the use of Ethidium Bromide, used for gel analysis.

The first task was conducted under a chemical hood and with the supervision of our PI or his doctorate students. The second, as practiced by all other university personnel, was handled with great care and with personal safety equipment.

  Although some of the organisms we handled could potentially have posed minor risks to the environment if they were to be brought out of the lab (for example, Agrobacterium tumefaciens is a plant pathogen that can damage a wide range of plants), simple actions were taken to ensure no environmental exposure occurred, such as the careful isolation of the specimens in our lab. Transgenic material was disposed of in bags that were later run through an autoclave.

Our main challenge regarding lab safety involved testing the activity of our degradation pathway through our transformed organisms. TCDD, one of the most toxic pollutants on earth, is known to cause an array of severe symptoms in humans and animals. Short-term exposure of humans to high levels of dioxins may result in skin lesions and altered liver function. Long-term exposure is linked to impairment of the immune, reproductive and nervous systems, as well as increased incidence of cancer. Because of the long-term persistence of TCDD in the human body, damage and impairment to ones health can show even decades after exposure.

Due to its extremely high toxicity, our university’s safety official did not allow the usage or study of TCDD within our labs. Instead, we used less-toxic derivatives of the same compound, such as Dibenzofuran and some PCB’s. Though they are less toxic than TCDD, these compounds are not entirely safe. Dibenzofuran can cause skin, eye, nose and throat irritation, but is not known to cause cancer or birth defects. 1,2,4,5-Tetrachlorobenzene, a PCB, has many short-term effects similar to TCDD, but, like Dibenzofuran, it is not known to cause long term harm. Since they are chemically similar to TCDD, these compounds were helpful for our research.

To ensure our safety and that of our peers, any work with Dibenzofuran and PCB’s was conducted solely under a chemical hood and with proper protective lab-gear by our trained and qualified lead researcher Amichai Baichman-Kass, with close monitoring from our PI. Using only disposable equipment when possible while wrapping any non-disposable tool, we were able to prevent the permeation of these materials outside of the chemical hood. Any and all contaminated waste was disposed of in the correct waste-containers and sent for treatment as dictated by our university’s safety protocol. Additionally, the appropriate lab-safety gear – including goggles, gloves, coats, etc. – were used in all lab-related activities.