What’s your biggest concern for your safety when walking into work each morning? That you’ll get a papercut or burn your tongue on your morning coffee? Maybe if you’re in a higher risk profession (like a contractor) you’re worried about something falling on your head. As a scientist, may researcher enter the lab every day and have to worry about being infected by what they are researching!
Human tissue and blood may contain viruses like HIV or hepatitis that’s just needs entry into your body through a cut or in the mucus membranes of your nose. Or maybe you’re working with viruses like the flu to see how they infect cells. And what of those people who are studying the deadliest diseases like Ebola – how do they study these diseases or work to develop vaccines or treatment drugs without getting Ebola themselves? BIOSAFETY!
Wow. Boring. Right? Well, kind of. I spent this last week taking a refresher course on biosafety and the reading was DULL, but sitting down to think about all of the implications it becomes fascinating.
The thing is, anything that would infect you is likely invisible. If you’re working with human tissue or blood, you can see the blood but not what might be inside of it (bacteria or a virus) that could infect you. And if you drop a blood tube on the floor, you can see the pool of blood but not the microscopic aerosolized droplets in the air just waiting to be inhaled. So how does a scientist take care of these hazards not just so they don’t get sick but so they don’t infect the public as well?
Good news is that scientists think about this a lot. First, depending on what you’re working on depends on how careful you have to be. Compare this to the difference between giving a 4-year-old plastic play-doh scissors versus sharp surgical scissors – they have different risks associated with them and you’d treat the kid using them in different ways. In the same way, working with things that are not known to infect humans and cause disease (like bacterial cells) don’t need to be handled as carefully as those that cause deadly diseases that are spread through the air (like Ebola). This is what defines the “risk group” on a scale of 1-4, where 1 is the lowest risk and 4 is the highest. The play doh scissors or bacterial cells would be Risk Group 1 and the sharp surgical scissor or Ebola virus would be Risk Group 4.
This then helps researchers figure out what protective measures need to be taken – also called Biosafety Levels (abbreviated as BSL) 1-4. For example, level 1 can be done in the laboratory out in the open wearing a lab coat and gloves. Level 2 requires research to be done in a biosafety cabinet so that anything that spills or is aerosolized is contained. Level 3 is for agents that cause moderate to severe disease and in this case the experiment needs to be completely contained in a glove box or in a special room with controlled air flow. Level 4 is for agents that cause lethal disease that has no treatment or cure (like Ebola). In this case the BSL-4 is what you may see on TV or movies where researchers are fully enclosed in a “space suit” to prevent any contact between the person and the agent.
In my lab, we regularly work with human tissue and blood and because the tissue or blood may be infected with certain biological agents, they are considered risk group 2. We always wear a lab coat and gloves and work inside a hood. When moving these tubes from one place to another, we make sure that there are at least two layers of containment – the blood tube is the first layer and this is inside a plastic bag as the second layer. We also get re-trained every year to make sure we remember how to handle spills (just in case).
Now because we’re all morbid creatures, I’m sure you’re wondering what’s happened when this hasn’t worked. Here is an article about the most common infections acquired in the lab and how they were acquired. For more newsy stories, here is a story about a researcher who contracted plague in the lab. Eek! Definitely reinforces the importance of being careful in the lab.