NIOSH recently investigated possible exposures of laboratory workers to several illicit substances, including cocaine, fentanyl, heroin, and methamphetamine. Following a request from the management of a police forensic sciences division, NIOSH conducted site visits at three of the division’s laboratories to observe work practices, assess conditions, interview employees, review records, and collect samples. NIOSH personnel reported finding detectable levels of the controlled substances in employees’ air and handwipe samples, and on laboratory surfaces. Since no occupational exposure limits for these substances have been set by the federal government or consensus organizations, NIOSH compared the workers’ exposures with other types of guidelines available from the pharmaceutical industry and at the state level. None of the fentanyl levels detected in air were higher than the OEL set by a fentanyl manufacturing company of 0.1 µg/m3, and no surfaces exceeded a fentanyl contamination limit of 1 µg/100 cm2 that was developed for internal use by a pharmaceutical manufacturer. However, seven laboratory surfaces surpassed the most commonly used state limit for methamphetamine contamination of 0.1 µg/100 cm2. Sampling also showed that even employees who had not worked with evidence containing the drugs on the day of NIOSH’s visit had detectable levels in air and handwipe samples. Despite the exposures, no employees reported symptoms that might result from handling cocaine, methamphetamine, or opioids at work in the three months prior to NIOSH’s investigation. However, NIOSH did find occasional evidence of symptoms associated with handling phencyclidine, or PCP, in facility records and one staff interview. Although reports of health effects resulting from these exposures were limited, NIOSH stresses that the division should take additional steps to protect employees. Unintentional employee exposure to illicit substances may have resulted from workplace practices and conditions. For example, NIOSH found that six of the eight fume hoods in the laboratory bench areas did not meet guidelines for average face velocities set by AIHA and the American National Standards Institute in the standard ANSI/AIHA/ASSP Z9.5-2012, Laboratory Ventilation. Likewise, the facilities’ respiratory protection program was not specific or instructive enough to adequately protect employees. NIOSH investigators also observed several employee practices that could result in contamination, such as inconsistent hand washing and eating and drinking in laboratories. NIOSH recommended a variety of changes to help protect laboratory workers, including adding enclosed or semi-enclosed ventilated workplaces; updating lab cleaning protocols; reminding all employees to wash their hands before leaving areas where controlled substances are kept or handled, and before eating and drinking; discouraging employees from eating or drinking in lab or storage areas; and updating personal protective equipment plans. NIOSH also advised that the division improve communication between employees, management, and law enforcement agencies, as well as address lab safety issues such as blocked emergency showers. For further details, read a PDF of the report on NIOSH’s website.