February/March 1996

Extremely Hazardous Chemicals: What They Are, How To Work With Them

The OSHA Lab Standard identifies three categories of substances whose usage in the lab demands special working areas and precautions. These "extremely hazardous chemicals" are: Carcinogens, Reproductive Hazards, and Chemicals With a High Degree of Acute Toxicity. What Are They?


The list of select carcinogens is quite long, especially if one combines the lists offered by OSHA, the International Agency for Research on Cancer (IARC), and the National Toxicology Program (NTP). A compiled list of Select Carcinogens can be found in Appendix C of the CWRU Chemical Safety Manual. Though many of these chemicals may seem quite ordinary, they have been designated as cancer-causing agents by one or more of these groups. Some of the most commonly used chemicals in the lab considered to be carcinogens are: benzene, chloroform, cadmium compounds, formaldehyde, and vinyl chloride.

Reproductive Hazards

Reproductive toxins are chemicals or other hazards which may manifest themselves in lethal ways on the fertilized egg, developing embryo or fetus, or which have teratogenic (malformation) effects on the fetus. Fetal effects may include: spontaneous abortions, low birth weight, still births, neonatal deaths, congenital anomalies and behavioral or developmental disabilities. In addition, these chemicals may cause infertility or fertility disorders in both males and females. While no employee may be prevented from the performance of her job due to pregnancy, any woman who believes that she is pregnant should discuss with her Principal Investigator potential risks of exposure and ways to minimize exposure to reproductive toxins. Some common lab substances considered reproductive toxins include: anesthetic gases (halothane methoxyfluorane), benzene, carbon monoxide, ethylene oxide, ethylene thiourea, ionizing radiation (x-rays and gamma rays), and mercury.

Chemicals with a High Degree Of Acute Toxicity

These chemicals may be fatal or cause damage to certain organs after only one exposure or after exposures of short duration. Classification in this category depends both on how quick the chemical enters the body and the effects that it has on the body. If you are unsure whether or not to designate an area for a chemical that may fall under this category, check to see if the chemical's container displays the diamond-shaped NFPA label. If in the blue health section of this label the chemical is registered as a "4", then it is definitely highly toxic. If it is registered as a "3", the chemical is still considered toxic and it is recommended that you designate an area for it; however, you may decide whether to do so depending on how often and in what quantities you use the chemical. If the chemical's container does not display the NFPA sign, consult the MSDS for toxicity information or call the Department of Occupational and Environmental Safety (x2907). Examples of Chemicals with a High Degree of Acute Toxicity include: hydrogen cyanide, hydrogen sulfide and nitrogen dioxide. How to Work With Them

Designate an Area

When working with one of these extremely hazardous substances, the OSHA Lab Standard requires that you designate an area specifically for such work. To designate an area for specific use, whether it be a whole section of the lab, a fume hood, or part of a bench top, it is vital that the section be properly and clearly labeled with the nature of the hazard. Signs should read: CAUTION: POTENTIAL CANCER HAZARD or CAUTION: POTENTIAL REPRODUCTIVE HAZARD. Areas used for storage of these chemicals should also be clearly marked. Make sure that you work with those chemicals only in that area. In addition, all employees who work in the area must be informed as to the nature of the hazard. "Employees" includes all maintenance personnel who come into contact with these areas on a regular basis. If the area designated is a large part of the lab, the area must be clearly identified and should not be in a high traffic area in order to minimize contact with other laboratory personnel.

General Procedures

  1. Follow all standard guidelines for safe laboratory practice when working with extremely hazardous chemicals; for example, wear eye protection, protective clothing, and gloves; do not smoke, eat, or drink in the lab.
  2. Do not wear laboratory clothing outside the lab, and discard disposable gloves immediately after overt contact with extremely hazardous chemicals.
  3. Wash your hands immediately after completing any procedures using chemical hazards.

Other Operational Procedures

  1. Cover work surfaces with impervious material such as dry absorbent plastic backed paper. The protective material should be decontaminated or disposed of after the experiment. Make sure that adequate chemical traps are used on all vacuum lines to prevent contamination.
  2. Any procedures involving volatile chemical hazards or those which may result in the generation of aerosols or particulates should be done in a fume hood, biological safety cabinet, or glove box. Aerosols can be generated from opening and closing vessels, transfer through weighing of chemicals, homogenization, open vessel centrifugation, and the application, injection, or intubation to experimental animals.
  3. If it is necessary to transfer the chemical from one site to another, place the chemical in a durable outer container. Contaminated material should be placed in biohazard bags labeled to indicate the potential hazard.
  4. Prior to the experiment, the PI should make plans for handling any chemical waste generated. Contact DOES for proper disposal procedures.

This information was taken from pages 46-50 and Appendix C of the CWRU Chemical Safety Manual. Please read over this section in greater detail if you want further information on any of the issues discussed here, or call DOES at x2907.

Surprise NRC Inspection!

The Nuclear Regulatory Commission (NRC) visited the campus recently for an unannounced inspection. Once again, CWRU received high marks. NRC inspectors found two potential concerns with CWRU's broad scope license. One concern focuses primarily on security of radioactive materials. This matter was highlighted just last month in January's issue of the newsletter, which reiterated the importance of securing radioactive material. The other violation dealt with the description of materials on forms used in the transportation of radioactive shipments across public roads.

At the week's end, NRC officials met with Kenneth Basch, Assistant Treasurer, Dr. Christopher Town, Chairperson of the CWRU Radiation Safety Committee, and Warren Malchman, Director of the Department of Occupational and Environmental Safety (DOES) for an exit interview. At that time, the NRC inspectors said how pleased they were with the University's safety program.

"The credit for this report goes not only to Warren Malchman and his staff but to all our lab workers, Principal Investigators, and the Radiation Safety Committee," Basch said "It's everyone's job to see that we have a safe working environment for University employees."

Malchman added, "NRC inspections are divided between a review of the Radiation Safety Office programs and tours of campus laboratories." Therefore, researchers and their staff deserve a large share of the thanks for contributing to this successful audit.

Radiation Training:  So Many Sessions to Choose From

Since the Radiation Safety Office offers many different training sessions involving the use of radioactive materials, it is important to understand the difference between them and what their completion allows attendees to do. There are three main training sessions offered by the Radiation Safety Office involving the use of radioactive materials: an orientation course, a New Training course, and a Retraining course.

  1. Often we will give an orientation session to students or ancillary personnel who do not directly work with radioactive materials. This is basically an awareness course about the use of radioactive materials and is open to everyone; however, it is not considered a full training session. People who attend only this safety awareness session are not qualified to use radioactive materials.
  2. The New Training course is a 3-hour course offered several times each month in the Quail Building. It is considerably more substantial than the orientation session and thoroughly discusses the safe use of isotope on the job. There is an exam at the end of this session which attendees must pass in order to use radioactive materials.
  3. The Retraining course is a refresher for those who have already gone through the New Training course. Each person using radioactive material must attend this retraining session yearly. The format of this course can also serve as the basic orientation session as described above.

The Radiation Safety Office also offers X-ray training sessions for those personnel who operate machines that use or produce X-rays. These people need to attend the course offered by our department only once. Additional training and refresher training is provided by the person in charge of the instruments. If you have questions about which session you have attended or need to attend please contact your supervisor as soon as possible. If you have only attended the orientation session you are not qualified to use radioactive material; you must complete the New Training course in addition to any others you may have already taken. See page 2 of this newsletter for course times and call the Radiation Safety Office (x2906) to register.

Radioactive Material Shipments: Standing Orders

Frequently researchers will request "standing orders" for radioactive materials, either for convenience or for price breaks. The Radiation Safety Office needs to know when these packages are expected to arrive; for example, if they are ordered weekly or biweekly, list the dates. Orders to be delivered only when the vendor is called by the lab will no longer be approved. Knowing when packages of radioactive material will arrive is a vital aspect of inventory control, and each lab as well as the university as a whole must have control of the amount of radioactive material present, its location, and its status, at all times. If you do not know when shipments will arrive, we ask that you place separate orders for each requested isotope so that their date of arrival will be fixed. Please have any orders to us by 2:30pm the day before the isotope is needed. If we receive the order after that time we cannot guarantee it will be processed by the next day. Call Radiation Safety with any questions concerning package requests (x2906).

Waste Minimization in Other Campus Programs

The generation of hazardous waste is not a problem unique to the science laboratory. Many other departments on campus generate other kinds of hazardous waste which can be effectively minimized, proving cost efficient for those departments and safer for their faculty and students. Programs like Studio Arts, the print shop, photography labs, and facilities and vehicle maintenance operations may not produce the variety of waste generated in a lab, but they still contribute greatly to the waste disposal problem. Waste from the Studio Arts include paints, thinners, other solvents, and heavy metals found in paint pigments. Printing operations generate waste inks and solvents. Photographic processing generates silver, developer, fixer, and rinsing solutions. Maintenance operations generate waste oils, vehicle maintenance waste, solvents, pesticides, water treatment chemicals, possible asbestos, and small quantities of other wastes. Some ways to reduce waste in these activities include:

  1. Replace oil-based paints with water-based paints in art instruction and maintenance operations wherever possible, and use non-toxic paints (solvent, lead, and chrome free) whenever possible.
  2. Spray-painting techniques can be modified to reduce waste. Set the correct air pressure for the spray gun and maintain a distance of 6-8 inches from the workpiece. Hold the gun perpendicular to the surface and trigger the gun the beginning and end of each stroke.
  3. Collect waste oils and solvents, separating those which are recyclable from those that are not. The Department of Occupational and Environmental Safety recently acquired a still that can recycle solvents to near-pure form. Call (x2907) to see if your department creates waste that could be distilled or recycled in some other way.
  4. Reduce pesticide waste by reducing pesticide application, using non chemical pest control methods, and preparing and using only the required minimum of a pesticide. Whenever possible use dry pesticides that are spread on the ground and watered into the ground to avoid spraying procedures and the resulting contaminated wash water.


Along with winter weather comes increased potential for injuries caused by slips and falls on icy outside walkways and wet floors, especially near doorways. The key to reducing the risk of injury from any hazard is to be aware of it and act accordingly. This includes eliminating or reducing hazards when possible, and protecting yourself against unavoidable ones. Here are some ways reduce the risk of seasonal injury:

  • Be sure to wear proper footwear and use handrails when possible;
  • Be more observant and deliberate while walking;
  • Clear up danger spots by removing ice and snow from walkways, mopping wet areas, removing or replacing ineffective floor mats, repairing leaks that result in ice formation, and displaying signs or barricades to warn others of slippery areas.

While Plant Services does an admirable job of keeping areas of the university clear of ice and snow, the rapidly changing winter weather makes it impossible for them to keep conditions safe at all times. We can help by notifying them of any hazardous spots at x2580.