Skip Navigation LinksSkip Navigation Links
Centers for Disease Control and Prevention
Safer Healthier People
Blue White
Blue White
bottom curve
CDC Home Search Health Topics A-Z spacer spacer
Blue curve MMWR spacer

Mercury Exposure Among Residents Of a Building Formerly Used for Industrial Purposes -- New Jersey, 1995

Potential sources of elemental mercury in residential settings include mercury switches, mercury-containing devices (e.g., thermostats and thermometers), and mercury obtained from laboratories, dental offices, or other industrial sources. In January 1995, pools of elemental mercury were found in a five-story factory building that had been converted to residential use in Hoboken, New Jersey; the building previously had been used to manufacture mercury vapor lamps. This report summarizes the investigation by the New Jersey Department of Health (NJDOH), the U.S. Environmental Protection Agency (EPA), the Agency for Toxic Substances and Disease Registry (ATSDR), the Hoboken Board of Health, and the Hudson Regional Health Commission (HRHC), which identified high levels of mercury vapor in the building and indicated that residents had been exposed to high levels of mercury. *

The five-story brick building included 17 condominium units and one attached townhouse with a total of 32 residents; six were children aged 9 months-8 years. Workers renovating an unoccupied condominium unit on the fifth floor initially found pools of mercury in the subflooring. The tenants' association hired a private contractor to remediate the contamination. During remediation, mercury-contaminated debris (e.g., wood flooring) was removed from the unit. In March 1995, a private consultant for the tenants' association found detectable levels of mercury vapor in units on all five floors. The highest levels of mercury were 5 ug/m3 in breathing zone areas and 888 ug/m3 in areas where liquid mercury was visible; both of those levels were recorded on the fifth floor. In comparison, for other residential properties known to have been contaminated with mercury, ATSDR has recommended indoor air mercury levels be less than 0.3 ug/m3 (0.0003 mg/m3) to protect public health (1,2).

In October 1995, drops of elemental mercury were observed in fourth-floor units, including on stove and countertop surfaces. Mercury vapor measured by a private consultant found levels on the fourth floor of 7 ug/m3 to 26 ug/m3. In late November, urine mercury levels for five residents of the two fourth-floor units ranged from 11 ug/L to 65 ug/L of urine (normal range: (0-20 ug/L). On December 15, NJDOH was notified of these findings, and on December 22, ATSDR and EPA were asked for assistance. Maximum air mercury levels detected by NJDOH were 10 ug/m3-50 ug/m3. With assistance from ATSDR, the Hoboken Board of Health, and HRHC, NJDOH analyzed urine specimens from 29 of the building's 32 residents; these samples indicated concentrations of mercury in the urine ranging from 5.7 ug/L to 102 ug/L. Of the 29 persons, 20 (69%) (including five of the six children), had urine mercury levels greater than or equal to 20 ug/L; eight of these residents had urine mercury concentrations greater than 56 ug/L.

On December 29, the Hoboken Board of Health, HRHC, NJDOH, and ATSDR provided the residents with results and interpretation of the urine tests and urged residents to relocate as soon as possible. Because the investigation indicated that residents in all parts of the building had been exposed to mercury vapors and because of the risks associated with vapors in the building and contaminated possessions, on January 3, ATSDR issued a health consultation report that the building was an imminent health hazard; on January 4, the city of Hoboken condemned the building. Inclement weather delayed moving and temporary relocation by EPA of the 32 residents and screening of their belongings for contamination until January 12, 1996. Residents were referred for medical evaluation at an environmental and occupational health specialty center. EPA is continuing the investigation to determine whether the building can be remediated.

Reported by: FS Sasso, MSW, Hoboken Board of Health. R Ferraiuolo, MPA, G Garetano, Hudson Regional Health Commission, Harrison; E Gursky, ScD, J Fagliano, MPH, J Pasqualo, MS, Environmental Health Svcs, New Jersey Dept of Health. R Salkie, MS, J Rotola, Environmental Protection Agency. Superfund Site Assessment Br, Exposure Investigations and Consultation Br, Div of Health Assessment and Consultation, Div of Health Education, Div of Health Studies, Office of Regional Operations (Region II), Agency for Toxic Substances and Disease Registry.

Editorial Note

Editorial Note: Elemental mercury is a shiny, silver-white odorless liquid. Some evaporation of elemental mercury occurs at room temperature to form mercury vapor, a colorless, odorless gas; the evaporation is enhanced by heat. Mercury vapor, the source of the exposures described in this report, is more dense than air and, therefore, settles on or near the floor. Because of this effect, children especially are at risk for adverse effects of exposure to mercury (3).

Mercury affects the central and peripheral nervous systems and the kidneys. Fine tremors in the fingers, eyelids, and lips are early signs of mercury toxicity. With increasing exposure, tremors in the hands and arms may interfere with precise movements and impair skills such as handwriting. Common behavioral symptoms of mercury toxicity include depression, irritability, exaggerated response to stimuli, excessive shyness, insomnia, and emotional instability (4). In occupational exposure studies, workers with urine mercury concentrations greater than 56 ug/L exhibited neurotoxic effects such as decreased performance on verbal concept formation and memory tests (5). Neurobehavioral tests and other standardized test batteries have been used to assess persons exposed to mercury and other neurotoxic agents in environmental and occupational settings (6-10).

Because of the health effects associated with exposures to mercury and other hazardous substances, these risks must be considered when industrial sites are converted for residential use. The investigation in this report underscores that industrial contamination may not be discovered until after buildings have been converted to residential use. When mercury is discovered in any residential setting, it should be reported immediately to the local health department or poison-control center. Persons at risk for exposure in such settings include residents, former factory workers, and workers involved in the renovation of such buildings.


  1. CDC. Mercury exposure in a residential community -- Florida, 1994. MMWR 1995;44:436-7,443.

  2. CDC. Acute and chronic poisoning from residential exposures to elemental mercury -- Michigan, 1989-1990. MMWR 1991;40:393-5.

  3. Agency for Toxic Substances and Disease Registry. Case studies in environmental medicine: mercury toxicity. Atlanta, Georgia: US Department of Health and Human Services, Public Health Service, 1992.

  4. Dreisbach RH, Robertson WO. Handbook of poisoning: prevention, diagnosis, and treatment. 12th ed. Norwalk, Connecticut: Appleton and Lange, 1987.

  5. Piikivi L, Hanninen H, Martelin T, Mantere P. Psychological performance and long-term exposure to mercury vapors. Scan J Work Environ Health 1984;10:35-41.

  6. Amler RW, Rice DC, Johnson BL. Assessment of mercury neurotoxicity through psychometric and neurobehavioral testing: a review. Neurotoxicol 1996;17:237-40.

  7. Amler RW, Lybarger JA, Anger WK, Phifer BL, Chappell W, Hutchinson L. Adoption of an adult environmental neurobehavioral test battery. Neurotoxicol Teratol 1994;16:525-30.

  8. Amler RW, Anger WK, Sizemore OJ, eds. Adult environmental neurobehavioral test battery. Atlanta, Georgia: US Department of Health and Human Services, Public Health Service, Agency for Toxic Substances and Disease Registry, 1995.

  9. Johnson BL, ed. Prevention of neurotoxic illness in working populations. New York: John Wiley and Sons, 1987:169-214.

  10. Sizemore OJ, Amler RW. Adult and pediatric neurobehavioral test batteries for use in environmental health field studies. Neurotoxicol 1996;17:229-36.

    • Copies of the health consultation report are available from ATSDR, telephone (404) 639-6066.

Disclaimer   All MMWR HTML versions of articles are electronic conversions from ASCII text into HTML. This conversion may have resulted in character translation or format errors in the HTML version. Users should not rely on this HTML document, but are referred to the electronic PDF version and/or the original MMWR paper copy for the official text, figures, and tables. An original paper copy of this issue can be obtained from the Superintendent of Documents, U.S. Government Printing Office (GPO), Washington, DC 20402-9371; telephone: (202) 512-1800. Contact GPO for current prices.

**Questions or messages regarding errors in formatting should be addressed to

Page converted: 09/19/98


Safer, Healthier People

Morbidity and Mortality Weekly Report
Centers for Disease Control and Prevention
1600 Clifton Rd, MailStop E-90, Atlanta, GA 30333, U.S.A


Department of Health
and Human Services

This page last reviewed 5/2/01