Wednesday, May 6, 2009

Safety information on handling of large quantities of organolithium compounds.

In all of this conversation about the UCLA/Sheri Sangji situation, I felt it important to get some useful information about handling large quantities of organolithium (such as n-butyllithium or tert-butyllithium) compounds out there.
From the review "Organolithium Compounds - Industrial Applications and Handling" by Franz Totter and Peter Rittmeyer, a chapter in "Organometallics in Synthesis: A Manual", M. Schlosser, John Wiley & Sons, New York.

Toxicology: The toxicological properties of organolithium compounds refer to the properties of the hydrolysis products. The caustic effect of lithium hydrolysis leads to severe irritation of the skin, mucous membranes, eyes and respiratory tract. The lithium ions is considerably more toxic than the sodium ion. On the other hand, certain forms of manic-depressive diseases are treated with dosages of lithium carbonate. [Interesting addition -- CJ.] 


Personal Safety: All personnel working with organolithium compounds on an industrial scale should be protected appropriate measures, i.e. face and eye protection, leather gloves, protective clothing against fire, protective shoes.
The staff in production plants wear leather suits, which are recommended because of their high thermal insulation capacity. The clothing is made from impregnated leather as it soaks up much less liquid than unprotected leather. The leather suits must not have any pockets outside in order to avoid any trapping of liquids. As leather shrinks somewhat in a fire or it may be necessary to remove this clothing quickly, it has rows of snap fasteners along the arms and legs. Another suitable material for protective clothing is Nomex, an aluminum coated fibre. Compared with leather it has a lower thermal insulation capacity and it is more sensitive to alkali. 
The face and eyes are protected by goggles and face shields fixed on the worker's helmet. Gloves should be made of leather. To prevent electrostatic discharges, the personnel should wear protective shoes with conductive soles.


Fire Fighting: When working with organolithium compounds one should always keep in mind that there is the possibility of spontaneous ignition. Therefore, all necessary equipment for fire fighting should be kept available, e.g. portable extinguishers for fighting small fires and mobile, larger extinguishers for fighting larger fires. In addition, boxes with ground limestone powder and shovels should be kept on hand for covering spilled solutions and extinguishing small fires. Fires must be NOT fought with water, carbon dioxide or halogenated hydrocarbons (halons) as they react vigorously with organolithium compounds.
Suitable media for fire fighting are ground limestone powder (for small fires), sodium hydrogen carbonate-based extinguishing agents (not for concentrated organolithium compounds and sodium chloride-based extinguishing agents (e.g. Totalit M.) 
For personnel, protection blankets and self-rescue showers should be readily accessible. Self-rescue showers are devices that release a shower of extinguishing powder when activated by stepping on a floor plate. It makes sense to install water showers or tempered water basins outside a production plant to extinguish the fire of a person's clothing or to wash off alkalinity from the skin." 

UPDATED: Removed boneheaded error in key portion. Whoops!

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