A fire on August 25, 1985, in a chemical storage vault at a New Jersey college resulted in contamination of one wing of a large multi-purpose building (175,000 square feet) with mercury, nitrobenzene, and pyridine. Elevated levels of polychlorinated biphenyls (PCBs) were also found in the debris without an identified source (PCBs were not stored in the vault). During decontamination by a contractor, gas chromatography/mass spectography of the debris showed PCB levels ranging from 100 to 750 parts per million (ppm). Additional sampling showed PCB levels of 2,000 ppm in lubricating grease from the air-handling units. Three other wings of the building also showed PCB contamination in the air, on surfaces, and in bulk samples of grease and ceiling tile although no evidence of fire or smoke damage was present in these areas. Each wing has multiple air-handling units that are separate and distinct from those where the fire occurred.

On October 11, 1985, the Public Employees Occupational Safety and Health Project of the New Jersey Department of Health (NJDH) was called to help identify the source of PCBs. NJDH subsequently asked the National Institute for Occupational Safety and Health (NIOSH) to provide technical assistance in the environmental assessment. Air samples taken before cleanup showed PCB levels ranging from 0.2 ug/m((3)) to 1.6 ug/m((3)) in various areas of the building; surface-wipe samples from the same areas and time period showed levels of 0.1 ug/100 cm((2)) to 7.2 ug/100 cm((2)). Samples taken after cleanup indicated that the cleanup process had been adequate in some areas but not in others. Some PCB levels were even higher than before cleanup (air: 0.8 ug/m((3))-3.9 ug/m((3)); surfaces: 0.7 ug/100 cm((2))-10.5 ug/100 cm((2))).

Although the post-cleanup results did not help to identify the source of PCB contamination, the problem appeared to be ongoing. After reviewing the sampling results from different areas, a secretary at the college noticed a similarity in the ceiling tiles in those areas with high PCB levels. In February 1986, a consultant hired by the college pursued the secretary's observation and evaluated ceiling tiles throughout the school. Those areas with consistent evidence of contamination had hidden-spline ceilings with 1'x 2' and 1'x 4' tiles.

Representatives from the New Jersey Department of Environmental Protection and the Environmental Response Team of the U.S. Environmental Protection Agency (EPA) assisted the NJDH in conducting a quality control review of the consultant's sample collection and preparation. Analytical results from both the EPA contract laboratory and the consultant's laboratory showed extremely high levels of PCBs (15,300 ppm- 51,000 ppm) in samples scraped from the painted surface of the 1'x 2' and 1'x 4' ceiling tiles. These tiles were identified as Armstrong Travertone Sanserra.

In meetings on March 24 and April 1, 1986, representatives from Armstrong World Industries, Inc. indicated that Aroclor 1254 (a commercial formulation of PCBs) had been added to a prime coating formulation used on three types of ceiling tiles (Travertone Sanserra, Santaglio, and Embossed Design) that were manufactured in 1969 and 1970. These tiles had been marketed throughout the country for use in commercial buildings.

The NJDH conducted bulk sampling throughout New Jersey of 65 different ceiling tiles from 25 buildings, including seven county and state colleges, 16 state office buildings, and two hospitals. They analyzed Travertone Sanserra tiles installed in these buildings in the late 1960s and early 1970s but found no detectable levels of PCBs (detection limit: 5 ppm).

NJDH representatives met with the college staff working in the contaminated building to discuss the levels of PCBs found in the building and the possible effects of PCB contamination. All employees were offered office space in other campus facilities; several pregnant women were relocated. Eleven maintenance employees were at high risk because of working either on the building's ventilation system or directly with the contaminated tiles. Laboratory tests of sera from these workers showed blood levels of PCBs ranging from 5.2-10.3 parts per billion. These levels are comparable to those found in the general public and do not reflect excessive exposure. Maintenance workers were provided with special protective equipment for future use.

The college is implementing a plan to remove PCB-containing tiles and to decontaminate the surfaces in affected areas. Armstrong has agreed to take financial responsibility for these precautions. The criteria after decontamination will be PCB levels of less than or equal to 1 ug/m((3)) in air and less than or equal to 0.5 ug/100 cm((2)) on surfaces*. Reported by J Fagliano, A Freund, K O'Leary, KD Rosenman, V Runnion, Div of Occupational and Environmental Health, New Jersey Dept of Health; Environmental Response Team, US Environmental Protection Agency; Div of Surveillance, Hazard Evaluations, and Field Studies, National Institute for Occupational Safety and Health, CDC.

Editorial Note

Editorial Note: Although epidemiologic evidence is inconclusive (3), animal studies have revealed that PCBs are "probable" human carcinogens (4), and adverse reproductive effects have been found in experimental animals (5-8). For airborne PCBs, the Occupational Safety and Health Administration has promulgated a permissible exposure limit of from 0.5 mg/m((3)) (54% chlorine content) to 1 mg/m((3)) (42% chlorine content) as an 8-hour time-weighted average (9). NIOSH recommends that airborne exposure to PCBs in the workplace be limited to less than or equal to 1 ug/m((3)), the minimum reliably detectable concentration (9). Although no standard evaluation criteria have been set for industrial surfaces contaminated with PCBs, EPA has recently proposed a limit of 100 ug/m((2)) in high-use areas where "people can make frequent and regular skin contact with surfaces".

Fires involving transformers that contain PCBs have been reported as a source of PCB contamination in office buildings (10-12). This is the first report of PCB contamination resulting from ceiling tiles. Although the contamination was discovered during sampling for chemical contamination after a fire in a chemical storage area, the following evidence strongly implicates ceiling tiles as the source of PCBs: 1) although the fire was localized in one wing, PCB contamination was found throughout the building; 2) each wing of the building has multiple, separate air-handling units; and 3) samples scraped from the surface of new ceiling tiles from a box that had not been opened previously showed a concentration of 30,000 ppm PCBs.

According to Armstrong's records, they used the PCB formulation as a flame retardant and plasticizer on approximately 6 million square feet of tile produced in 1969 and 1970, representing 1% to 2% of their tile output in those years. Aroclor 1254 was present in the coating formulation at concentrations ranging from approximately 4.4% to 12.3%, by weight. The coating was used on 1'x 1', 1'x 2', 1'x 4', and 2'x 2' tiles but not on the 2'x 4' tiles most commonly found in commercial buildings. Armstrong's records do not indicate where the remainder of the tiles were used.

Building owners should check to see whether they have tiles of this brand, size, and age and, if so, should submit a portion of tile to a certified analytical laboratory for PCB analysis.

References

1. National Institute for Occupational Safety and Health. Criteria for a recommended standard: occupational exposure to polychlorinated biphenyls (PCBs). Cincinnati, Ohio: US Department of Health and Human Services, Public Health Service, 1977; DHEW publication no. (NIOSH)77-225.

2. National Institute for Occupational Safety and Health. Health hazard evaluation report no. HETA 85-414. Cincinnati, Ohio: US Department of Health and Human Services, Public Health Service, (in press).

3. Brown DP, Jones M. Mortality and industrial hygiene study of workers exposed to polychlorinated biphenyls. Arch Environ Health 1981;36:120-9.

4. International Agency for Research on Cancer. The evaluation of the carcinogenic risk of chemicals to humans: polychlorinated biphenyls and polybrominated biphenyls. Lyon, France: International Agency for Research on Cancer, 1978:18.

5. Villeneuve DC, Grant DD, Khera K, Clegg DJ, Bear H, Phillips WE. The fetotoxicity of polychlorinated biphenyl mixtures (Aroclor 1254) in the rabbit and in the rat. Environ Phys 1971;1:67-71.

6. Allen JR, Carstens LA, Barsotti DA. Residual effects of short-term, low-level exposure of nonhuman primates to polychlorinated biphenyls. Toxicol Appl Pharmacol 1974;30:440-51.

7. Barsotti DA, Marlar RJ, Allen JR. Reproductive dysfunction in rhesus monkeys exposed to low levels of polychlorinated biphenyls (Aroclor 1248). Food Cosmet Toxicol 1976;14:99-103.

8. Allen JR, Barsotti DA. The effects of transplacental and mammary movement of PCBs on infant rhesus monkeys. Toxicol 1976;6:331-40.

9. CDC. NIOSH recommendations for occupational safety and health standards. MMWR 1986;35(1S):27S.

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