Many readers know that research assistant Sheri Sangji died from burns sustained in a laboratory fire in the lab of UCLA professor Patrick Harran. Harran and university Regents are up on felony charges for their part in the incident. I understand that the charges are based on occupational health and safety violations related to the incident.
[The excellent blog Chemjobber has been following this story. I might add that this blog should be put on your Favorites list if it isn’t already there. The author puts a lot of work into it and it shows.]
Sangji was transferring t-butyllithium when her plastic syringe came apart and a quantity of the pyrophoric solution was splashed on her and ignited. She sustained fatal burns when her clothing caught fire and she died 18 days later.
Syringe techniques are common and the use of plastic syringes in such transfers of lithium alkyls is not unusual or automatically over-dangerous. However, some syringes have what is called a Luer tip where a syringe needle is attached solely by friction.
Another design has a Luer lock where the needle is affixed with a twist of the needle into a friction lock. The former design, with the tubular tip and no locking mechanism is prone to disconnection under tension and on withdrawl of the needle from the septum on a pressurized bottle, the needle is likely to squirt bottle contents onto the worker. The Luer lock largely prevents this type of accident.
Another failure mode is when the plunger is inadvertantly withdrawn completely from the barrel of the syringe. Minimally, this would release the contents from the barrel, possibly on the operator. If the plunger is pulled completely out while the needle is still in a pressurized bottle, a fountain of liquid may discharge, possibly on the operator.
Syringe plungers with a rubber tip are prone to swelling in organic solvents and may become difficult to move during a single use. If the plunger is pulled with great force, it might release suddenly causing it to come out of the barrel along with the contents.
Other syringes have plungers that provide a seal by plastic-on-plastic pressure. The seal depends on the elasticity of the barrel to accomodate the slightly oversized plunger. These syringes do not come with Luer locks and as such, are not forgiving of less than skillful use.
I do not know exactly what technique Sangji was using. Aldrich distributes literature on the use of a cannula in the transfer of air sensitive liquids. That is fine, but if you want 0.1 to 60 mL of RLi, a syringe is the most expeditious method for delivering a precise aliquot in my opinion.
Experimentalists are often stricken with a cowboy mentality. If you have never had a serious incident with a material, it is easy to get a bit cavalier. But handling metal alkyls is a lot like handling rattle snakes- you have to be careful every single time.
A subsequent post offers suggestions on due diligence for ressearch professors.