Somewhere on the campus of a northeastern US university, a set of epoxy footprints across a concrete walkway marks the path of an investigator who left the laboratory after spilling and then stepping in radioisotope phosphorous-32. He had failed to perform a closedown survey before leaving the lab. Radiation officers conducting a routine survey tracked the spill through the lab, down the stairs, and across the campus to the parking lot. Though the hard, polished surfaces inside the building could be completely decontaminated, the porous, outdoor surfaces could not. The outdoor footprints had to be covered with a substance thick enough to shield the passers-by from the radioisotope's decay; thus, the epoxy.
For researchers who have never experienced an accident, lab safety is often a joke. Who hasn't groused over annual training seminars that remind investigators that it is not safe to eat, drink, smoke, or apply cosmetics in the lab? Such apathy makes safety officers' jobs perhaps the most thankless in any research environment, yet researchers look to them first when trouble strikes.
Laboratory accidents are generally avoidable. That's the position taken by the federal government's primary regulatory oversight body, the Occupational Safety and Health Administration. OSHA may impose fines on an institution in the event of an accident; the magnitude of such fines depends, in part, on institutional records that document the safety measures in place, the safety training provided, and those who attended.
For the most part, biological research laboratories are quite safe these days, says Claudia Mickelson, deputy director of biosafety programs for Environmental Health and Safety (EHS) at Massachusetts Institute of Technology (MIT). Data from the Bureau of Labor Statistics (BLS) bear this out (www.bls.gov): Between 1991 and 2001, the rate of recordable injury cases per 100 full-time workers in research and testing services decreased by one-third. In 2001, there were 11,700 recorded occupational injuries in this group, but more than half (7,100) resulted in no loss of working days. This decrease mirrors reductions in injury rates for private industry overall, according to BLS data, and is not likely due to changes in reporting standards, says a BLS spokesperson.
Courtesy of Marilee Ogren
DANGEROUS PLACES Despite decreased risk, serious incidents occur all too frequently. And it takes only one serious incident to remind scientists that laboratories are dangerous places in which to work. Karen Wetterhahn, a 48-year-old Dartmouth College chemistry professor, died 10 months after a few drops of dimethylmercury spilled on her disposable latex gloves and absorbed through her skin.1 DMM is a neurotoxin that, after a latent period, leads to loss of sensation in the legs, loss of balance, impaired vision, speech, and hearing, and eventually coma and death. Wetterhahn was unaware that DMM permeates latex, PVC, and neoprene almost instantaneously. At the time, in 1996, material data safety sheets for DMM did not provide this information because it was not yet known.
In another incident, Beth Griffin, a 22-year old research assistant working at Yerkes Primate Center in Atlanta, died six weeks after biological material from a caged rhesus macaque splashed in her eye.2 The potentially fatal consequences of human infection with monkey B virus (Cercopithecine herpesvirus 1) were known at the time--70% of infected humans die--but caged animals were considered a low risk, and the researcher wore no protective eye gear.
And in another incident, a young graduate student received second-degree burns when an unmarked bottle of hazardous waste exploded while she was pouring unused sulfuric acid into it. The bottle was in a fume hood but the sash was wide open, and contaminated liquid splashed into the lab, on the student, and on the floor.
Injuries can occur during even the most mundane activity. In one incident, a young researcher untwisted the cap on a flask of agar before putting it in the microwave oven, but the lid resealed as the gases heated in the flask. The force of the resulting explosion blew the door off the oven's hinges and into the researcher's chest while flying glass cut her face.
Most accidents are less spectacular. Laboratory workers most often have razor cuts (32%) and bruises, sprains, strains, and fractures (21%).3 Injuries from broken glass, sharps, collisions, and falls are as common in the laboratory as they are elsewhere, but chemicals, biological materials, and radioisotopes compound the risks.
"Ethanol fires are probably the most common accident in an instructional laboratory," says Kate Bacon Schneider, biology technical instructor at MIT. "Students just don't realize how easy it is to ignite a flask of ethanol or a glove with some ethanol on it. Besides, they're often tired and not always vigilant. That and their inexperience are my main worries. I don't want to see someone's clothes or hair on fire."
TECHNOLOGY HELPS, HURTS At least part of the overall reduction in injury rates may be attributable to improved technology. These days, biological materials are being stored and used in smaller quantities as the sensitivity of molecular biological techniques has increased, so the risk from exposure is less even in the event of a spill or accident. Also, safety has been built into properly designed laboratories, which are equipped with fume hoods, safety cabinets, directional airflow, and glove boxes.
Instrument manufacturers now include a variety of safety features in their products, such as safety interlocks in electrical equipment that cut off current to prevent electric shock. "I spend most of my time on prevention through risk assessment and training," says MIT's Mickelson. "Preventive measures based on risk assessment are developed in collaboration with the investigators, and most EHS offices provide regular training seminars for proper use of research materials such as radioactive chemicals and recombinant DNA research." Yet, laboratory equipment can also present major hazards. High-voltage electrophoresis equipment, ultraviolet light, heat sources, and cryogenic materials all pose potential physical dangers that should be neither ignored nor minimized.
"THE TOP OF THE HOUSE" Seminars and lab surveys given by EHS officers help researchers keep safe and comply with federal and state regulations, but the lab head is expected to inform laboratory workers of the necessary safety seminars and to set a good example. "Safety starts at the top of the house," says MIT's assistant safety officer, Bill McShea.
Experienced researchers sometimes cut corners on safety pro cedures without putting themselves at risk, because they understand the materials and the dangers. Students, despite their lack of the same depth of knowledge, often model themselves after their mentors. Keith Kidd, EHS director at Boston College, says lab heads who avoid safety personnel and ignore their advice perpetrate this attitude in their students and postdocs: "Combine a cavalier attitude with inexperience and a youthful sense of invulnerability, and that's an accident waiting to happen. It is not in the lab head's best interest."
Kidd is confident that his program is effective but worries about problems outside of his control, such as loss or theft of hazardous reagents. "The only way to avoid this type of thing is to stress accountability with audits, surprise visits, and lab surveys," he says. "Researchers must know that they are responsible for hazardous materials left unattended and must account for their use. It's an important balance, though, because you don't want to make it harder for researchers to do their work."
Erica P. Johnson
REGULATORY OVERSIGHT Investigators appreciate such a balanced approach. Grant Balkema, associate professor of biology at Boston College, says, "There has been an overall improvement in the quality of the safety programs and in safety personnel since I was a student. The relationship is more collaborative now. I'm happy to accommodate the recommendations of officers who think intelligently and flexibly."
Along with OSHA as the main body overseeing worker protection related to laboratory environments, including work with laboratory animals, the Centers for Disease Control and Prevention and the National Institutes of Health publish the Biosafety in Microbiological and Biomedical Laboratories (BMBL) manual.4 It describes recommendations for work with infectious agents according to the four Biosafety Levels and parallels the NIH Guidelines for Research Involving Recombinant DNA Molecules.5 The majority of laboratories in the United States are considered Biosafety Level 1 (least dangerous) or Level 2; there are only five Level 4 facilities (two each in Georgia and Texas, and one in Maryland). The principles of biosafety outlined in the BMBL manual focus on laboratory practice and technique, safety equipment, and facility design.
Finally, the Association for Assessment and Accreditation of Laboratory Animal Care (AAALAC) accredits and evaluates programs that deal with laboratory animals. "Institutions go through our voluntary system of external validation to promote high standards of laboratory animal care and use among their researchers and research staff," says Richard C. Van Sluyters, professor and member of AAALAC's Council on Accreditation and chair of the Animal Care and Use Committee at the University of California, Berkeley. "The accreditation process has had a very positive impact on the health and safety of research personnel at Berkeley."
Concern for the health and safety of research personnel motivates the local, state, and federal workers who labor to keep laboratories safe. But prevention begins in the lab, and an informed researcher, who is alert to potential dangers and willing to expend the effort necessary to avoid them, is unlikely to be caught unawares. The most important maxim: Be prepared. Karen Kelley, a certified industrial hygienist who works at the University of Pennsylvania's office of Environmental Health & Radiation Safety, advises researchers working with new or unfamiliar chemicals to consult their institutional safety offices. She also recommends contacting glove manufacturers; these companies often have information available online about the resistance of various glove types to a range of chemicals.
Meanwhile, on that northeastern university campus, more than 143 days--10 times the 14-day half-life of phosphorous-32--have elapsed since radiation safety workers laid down footprint-shaped slabs of epoxy. The radioactivity may be gone, but the epoxy remains--a tangible lesson in laboratory safety.
Marilee P. Ogren (email@example.com) is a freelance writer in Boston.
Additional reporting provided by Jeffrey M. Perkel.
1. K. Endicott, "The trembling edge of science," Dartmouth Alumni Magazine, 1998.
2. "Fatal Cercopithecine herpesvirus 1 (B Virus) infection following a mucocutaneous exposure and interim recommendations for worker protection," Morbid Mortal Wkly Rep, 47:1073-6,1083, 1998.
3. Howard Hughes Medical Institute, "Knowing how to practice safe science," 1998; available online at info.med.yale.edu/caim/hhmi.
4. J.Y. Richmond, RW McKinney, eds., Biosafety in Microbiological and Biomedical Laboratories, 4th ed., US Dept. of Health and Human Services, pub. CDC 93-8395, 1999; available online at www.cdc.gov/od/ohs/biosfty/bmbl4/bmbl4toc.htm.
5. National Institutes of Health, Guidelines for Research Involving Recombinant DNA Molecules, 2002; available online at www4.od.nih.gov/oba/rac/guidelines/guidelines.html.