On November 18, 20, and 21, 2008, we conducted an HHE at the CPD, CIS. The HHE request, submitted by CPD management, concerned a possible cancer excess among former and current CIS employees. Other concerns listed in the request were IEQ, adequacy of the ventilation systems, chemical exposures encountered during criminal investigation procedures, and effectiveness of the engineering controls at minimizing chemical exposures in the crime lab. We obtained medical and employment information on current and former employees reported to have cancer. We verified their cancer types and employment duration in the CIS. We inspected all engineering controls, including the HVAC system, for deficiencies. We took measurements of CO2 and airflow on the fourth, fifth, and sixth floors to evaluate the IEQ and performance of the HVAC system. We collected area air samples in the locations adjacent to the crime lab and photo-processing lab to evaluate the migration of chemicals throughout the building. We collected personal air samples for ethyl acetate during ninhydrin spraying, ethyl cyanoacrylate during super glue fuming, carbon black during fingerprint powder application, ammonia and sulfur dioxide during photo processing, and hydrogen peroxide during luminol spraying. We interviewed employees in a private setting to allow them to express their concerns and describe any symptoms related to their work. The numbers and types of cancer reported among employees did not appear unusual, and the cancers were unlikely related to workplace exposures. Carbon black was the only chemical we identified that is used regularly and is listed by IARC as a possible human carcinogen. NIOSH considers carbon black carcinogenic only if it contains more than 0.1% PAHs. The carbon black used in the fingerprint powders did not contain measurable PAHs. Personal exposures to carbon black and all other chemicals evaluated in this survey were below applicable OELs. The results of the area air sampling demonstrated the migration of ethyl acetate from the crime lab to other areas on the fifth floor. The super glue fuming chamber and associated filtration system controlled ethyl cyanoacrylate vapors inadequately. In addition to the crime lab, the photo-processing lab and bathrooms on the fourth and fifth floors were under positive pressure, which may allow contaminants and nuisance odors to move to other areas of the building. The evidence room was under slight negative pressure. However, because the evidence room did not have a dedicated exhaust system, the odor of the marijuana stored there as evidence was pungent inside and outside the room. The fourth and fifth floors had multiple AHUs. Most of the outdoor air was delivered to the plenum (the space above the suspended ceiling) rather than ducted directly to the AHUs. These independently controlled AHUs likely contributed to the wide range of airflows (0-288 ft3/min) measured at the ceiling diffusers. Most of the HVAC air filters we inspected were dirty and needed to be replaced. In the afternoon (peak occupancy), CO2 levels in the office areas on the fourth and fifth floors were greater than 700 ppm above the outdoor air levels (average of 425 ppm). This suggests that inadequate outdoor air was delivered to the office areas during peak occupancy. Because ethyl cyanoacrylate vapors irritate the respiratory system and mucous membranes, we recommend replacing the super glue fuming chamber with a chamber that controls generated vapors more effectively. The HVAC system should be redesigned so that outdoor air is delivered to the AHUs and actively delivered to the occupied areas of the building. Filters in the HVAC system, fingerprint powder downdraft table, and small super glue fuming chamber should be replaced routinely. The ventilation system should be adjusted to maintain negative pressure in the crime lab, photo-processing lab, bathrooms, and other areas where contaminants and nuisance odors are generated. A dedicated exhaust system should be installed in the evidence room to control odors. A forensic laboratory health and safety plan should be developed. This plan should describe occupational hazards, standard operating procedures, engineering controls, and the PPE required for each method used to process criminal evidence.
Cancer; Cancer-rates; Police-officers; Emergency-responders; Indoor-air-pollution; Indoor-environmental-quality; Ventilation; Ventilation-systems; Photographers; Engineering-controls; Control-technology;
Author Keywords: Police Protection; crime lab; criminal investigation; forensics; latent fingerprint detection; fingerprint powder; carbon black; ninhydrin; luminol; ethyl acetate; ethyl cyanoacrylate; super glue fuming; indoor environmental quality; IEQ; cancer cluster; police