Category: Pointers Resources

Pointers Resouces in note index

Warning: Azidophenylalanine

The unnatural amino acid azidophenylalanine is used for modifying and labeling proteins in biological and biochemical research. The azido group, though, is often a bad actor, leading to “energetic events,” (i.e., explosions).

A recent article in J. Org. Chem. (doi:10.1021/acs.joc.8b00270) by Mark Richardson, Gregory Weiss, and other University of California researchers describes an inexpensive synthesis of this amino acid. In the course of the research, the researchers studied the intermediates and final product using differential scanning calorimetry and discovered that azidophenylalanine “behaved like an explosive compound,” an unexpected result. The authors recommend that crystalline samples of azidophenylalanine not be stored for long periods and that all stocks of the material be kept in dilute aqueous solution.

Further details can be found in a Safety Note in Chemical & Engineering News.

Learn the fundamentals of toxicology in your spare time

The National Library of Medicine makes available an online short course on toxicology available at https://toxtutor.nlm.nih.gov/index.html. ToxTutor even offers a certificate of completion if you sign up for the Library’s free learning management system.

Another good nonspecialist introduction to toxicology is The Dose Makes the Poison: A Plain-Language Guide to Toxicology (Frank, P., Ottoboni, M.A.; Wiley, 2011). This book provides an excellent introduction to toxic chemical hazards and is recommended for those who handle a variety of chemicals.

Lab safety posters

The safety posters below may be used by any JHU laboratory–just print them out and post!

Be sure to choose a poster suitable for your lab. A poster about lab coats is not appropriate in a mechanical lab where lab coats are forbidden (because they might catch on something). A poster about compressed gases might be a better choice in that case.

Rotate safety posters at least quarterly. Research shows that posters start to lose effectiveness quickly, so “switching them up” is a good way to keep your fellow researchers safety-aware.

   

Inert gases and hypoxia in the lab

Inert gases such as nitrogen and argon are commonly used in our laboratories. If the contents of a cylinder were suddenly released into the laboratory atmosphere, the oxygen content of the air could be reduced below the safe 19.5% level necessary to avoid hypoxia in lab occupants.

Find out how to determine if a worst-case release of inert gas can reduce oxygen concentrations below safe levels and what you can do about the risk in this Safety Note: Inert Gas Safety.

Incompatible chemicals in waste containers

Do you dispose of different types of chemicals? If so, you run the risk of mixing incompatible chemicals together in your waste containers. Refer to this chart (EPAChemicalCompatibilityChart) to help determine what you can put in the same waste container. The chart is fairly complex, but the topic is also fairly complex. Always be sure to use secondary references such as Safety Data Sheets to verify that your chemicals are compatible–the EPA chart is general, not specific.

New “Safety in Academic Chemistry Labs” edition published

The American Chemical Society has revised the commonly-used Safety in Academic Chemistry Laboratories for its eighth edition. All those who handle chemicals should be familiar with the information in this small booklet, although it is aimed particularly at first- and second-year chemistry students. Hardcopies can be ordered from the American Chemical Society (http://www.acs.org) or a free PDF can be downloaded from here.

Embolisms from high-pressure gas

Using high-pressure air or gases to blow off or dry parts can create embolisms—small bubbles in the bloodstream that cause blockages—if the nozzle comes in contact with your body. The law requires that you use special nozzles designed to prevent this risk. Alternatively, the gas pressure may be limited to allow gas to be used safely to clean and dry parts. The Laboratory Safety Advocate’s office has developed an inexpensive kit to help. Learn more in High Pressure Blow-Off Gas.

Equipment transfer safety

Equipment being relocated must move through public corridors and outside areas; equipment being repaired or disposed is being transferred to service or disposal personnel unfamiliar with your lab and its hazards. In all cases, you are responsible for protecting others from unknown contamination. Learn more in Equipment Transfer Safety Note.

Protect your eyes from high-intensity light

Protect your vision when working with UV germicidal lamps; lasers; welding and arc lamps; or other high–energy light sources. Special goggles limit the amount of light that can reach your eyes and skin. The type and amount of protection depends on the frequency, nature, and intensity of light. Learn more in Light eye protection.

Protect your face with a face shield

When a hazard involves a lot of energy or aggressive chemicals, your face may be at risk as well as your eyes. Also, Z87.1 or Z87.1+ rated eye protection may not be adequate to protect your eyes, so additional protection might be prudent. If you could injure your face in an accident, use a face shield to protect your face – learn more in High energy facial protection.