Lab hazard

D. SIMONDS

No one told Karen Quigley her PhD project could make her ill. But during a clean-up of the rat room at Ohio State University in Columbus, Quigley had an asthma attack. She had developed an allergy to her rodent subjects — a health issue that persisted throughout her graduate studies and later postdoctoral work at Columbia University, New York. Quigley felt embarrassed wearing her "Darth Vader" get-up, a face mask with respirator, to handle the animals. "You need to do your work, so you just soldier on," says Quigley, who now sticks to humans at the US Department of Veterans Affairs New Jersey Healthcare System in East Orange. She enjoys her work, but would have liked to continue with animal models. Her allergy made that impossible.

Scientists are familiar with the clear dangers of laboratory work, such as concentrated acids and bases, sharp needles and radiation. But other health concerns are more subtle. Allergies and chemical sensitivities are a perennial threat to scientists who spend most of their time in the lab. Epidemiological data are scarce, so long-term hazards may be unknown. Even with known risks, those in a rush to collect data may skip safety measures. Generally they don't pay for their carelessness, but occasionally, lab health hazards can delay research, force a career move or cause serious injury or death (see 'Worst-case scenarios').

One study of animal-lab workers in Japan found that nearly a quarter of more than 5,000 survey respondents reported allergy symptoms (K. Aoyama et al. Br. J. Ind. Med. 49, 41–47; 1992). Rodents are widespread culprits, but other mammals, insects and plants can also cause problems.

Allergic symptoms can curtail scientists' time at the bench; with continued exposure, asthma may also occur away from the lab. If an allergy is likely to develop, it usually arises within a few years of starting animal work. "It's fairly common, especially if people have an allergy already," says Christian Newcomer, executive director of the Association for Assessment and Accreditation of Laboratory Animal Care International in Frederick, Maryland. For some, avoiding the trigger may be the only option. "People do walk away from animal research because of this," Newcomer says.

Pharmacologist Mary Lynn Baniecki of Raleigh, North Carolina, tried everything to get around her rat allergy that developed during a master's project at Northeastern University in Boston, Massachusetts. She wore a mask and full-length disposable lab gown, and showered immediately after leaving the lab. But nothing helped. Her allergist told her to stop animal work to avoid becoming "severely ill", she says. The diagnosis forced her to abandon her research tracking dopamine neurons.

Animals are not the only potential health issue in a laboratory. Chemicals and other materials can cause allergies or sensitivity. For example, 8–12% of health-care workers are allergic to latex, according to the US National Institute for Occupational Safety and Health (NIOSH).

Baniecki discovered the hazards of chemicals at her next position. Leaving the rats behind, she embraced structure-based pharmacology during a PhD at the State University of New York at Stony Brook. But two years into that work, she noticed the familiar signs — a tightness in her chest, a general sick feeling. By keeping a diary of activities and symptoms, she determined that she felt ill every time a colleague used gel electrophoresis to separate proteins. The source, Baniecki says, was the reducing agents used to break apart proteins. For those with a chemical sensitivity, the only answer is to minimize contact with the cause — not easy for something that is omnipresent in biochemistry labs. Baniecki had to rely on her colleagues to keep their reducing agents covered.

The working patterns of scientists make it difficult to collect epidemiological information on long-term health hazards. "It's the hazards that are not immediate that are the biggest problem," says Joe Crea, chief adviser on occupational hygiene for Safework South Australia in Adelaide. Scientists are a highly mobile population and health problems can go unreported. Diseases such as cancer can develop slowly so that by the time a person falls ill, there is no way to make a direct connection to their lab work. That makes it harder for safety managers to know exactly how dangerous certain chemicals may be.

Less than 2% of commercially available chemicals have been evaluated for carcinogenicity, according to the NIOSH. Instead, safety officers and scientists must make their best guess. It is assumed that ethidium bromide, a common reagent used to visualize DNA under ultraviolet light, is a carcinogen because it squeezes between the nucleotide bases of the genetic molecule, potentially causing mutations. Therefore, most researchers are careful to wear gloves when handling DNA gels, and some labs have switched to alternative DNA stains. Yet despite its suspected genome-altering properties, the scant data on ethidium bromide means it is not on the NIOSH list of potential occupational carcinogens.

Steve Benedict: "The laboratory is ultimately a very safe place."

Rapidly changing lab techniques, such as new synthesis procedures, can exacerbate safety concerns as chemicals with unknown long-term hazards come into vogue. Tim Brunker, an organic chemist at Towson University in Maryland, had no worries when synthesizing a new chemical entity during his postdoc at Dartmouth College in Hanover, New Hampshire. Brunker wore his usual lab attire — gloves and safety glasses with jeans and a T-shirt. After the preparation his nose itched, so he rinsed it. But after repeating the synthesis a few times, he broke out in a red, blotchy rash. It took a month of taking antihistamines around the clock for Brunker to recover. He stayed out of the lab, doing office work for much of that month, and avoided that chemical thereafter.

"In hindsight, I probably should have been more careful," Brunker says. "I never really thought that sort of thing could happen." These subtle health hazards are rarely discussed among lab workers. And researchers can view safety regulations as an exercise in overkill, particularly when even the lab supply of sodium chloride — table salt — comes with a warning that ingesting too much could be dangerous.

The laboratory is ultimately a very safe place, says Steve Benedict, director of environment, health and safety at the University of California, San Diego. In 18 years of managing lab safety at San Diego and elsewhere, he has not encountered a serious incident or fatality.

Despite the potential hazards of chemicals and procedures, most accidents that befall researchers are not specific to lab work. Among scientists, there were three times as many workplace injuries from trips and falls than from harmful substances or environments in 2007, according to the US Bureau of Labor Statistics.

Benedict says his office can usually help scientists with a specific allergy or sensitivity to continue with their research. But sometimes the problem is too severe. Benedict's advice for those rare few: "Maybe the lab really isn't the place for you to be."

worst-case scenarios

Laboratories are generally safe places, but sometimes a minor mistake can have consequences that go far beyond allergies or rashes. This is a selection of tragic incidents reported in the media over the past 15 years; they demonstrate the importance of taking great care in the lab.

A research assistant died in January this year from burns sustained in a university chemistry laboratory in California. Sheharbano Sangji had been working in the lab for only a few months when the plunger popped out of the syringe she was using to transfer tert-butyl lithium — which ignites spontaneously in air — causing her gloves and jumper to catch fire.

A chance splash of primate fluids cost research assistant Elizabeth Griffin her life in a 1997 incident at Yerkes Regional Primate Research Center research centre in Georgia. Because the rhesus macaques under study were caged, Griffin did not use safety glasses for the procedure being done. A piece of material contaminated with herpes B virus — probably urine or faeces — got into her eye and she died six weeks later.

Chemist Karen Wetterhahn spilt a drop of dimethylmercury on her gloved hand in 1996 at Dartmouth College in New Hampshire. At the time, it was not known that the chemical passes through latex, so she did not realize it had reached her skin. She fell ill five months later and died within the year.

In 2004, while drawing blood from Ebola-infected guinea pigs, Antonina Presnyakova accidentally stuck herself with the needle she was using. Presnyakova, a scientist at a virology laboratory in Russia, died two weeks later.

In 1994, a laboratory technician, working alone in a private lab in Perth, Australia, spilled hydrofluoric acid in his lap. He washed his limbs but did not apply calcium gluconate gel, the recommended treatment. The technician died 15 days later from multiple organ failure.

A.D.