What is the NER?

The NER is a critical, long-term effort that meets the need for collecting information concerning the potential impact of hazardous substances on human health. It is a listing of persons exposed to hazardous substances.  It contains subregistries for specific substances. There are currently four active subregistries-- trichloroethylene (TCE), trichloroethane (TCA), benzene, and  dioxin.  An important purpose of the National Exposure Registry is to help scientists understand how long-term exposure to hazardous substances may affect human health. This is done by identifying and following the health of individuals who have come into contact with specific substances at selected locations. Another  purpose of the Registry is to have a mechanism through which  participants can  be notified of the results of research related to  their exposure. The Registry program carries out its mandate by creating a large database of similarly exposed persons.  This database is used to facilitate epidemiologic research in ascertaining any adverse health effects of  persons exposed to low levels of chemicals over a long period. All data collected are confidential.  Names and addresses are protected under the Privacy Act and are not released without written permission of the registrant.

What happens to requests to be added to a subregistry of the National Exposure Registry?

Subregistries are site as well as substance specific. Individuals who meet specific eligibility requirements and respond positively when  contacted are included. Additional persons are not added after initial baseline interviews are completed.

Is the National Exposure Registry information available on the Internet? If not, when will it be available on the Internet?

Currently, information is not available on the Internet. We expect to  have NER information available sometime in 1999. A limited number of hard copies of final reports are available to any requestor.

Benzene Subregistry

Q: What is benzene?

Benzene is a naturally occurring substance produced by volcanoes and forest fires and is present in many plants and animals, but benzene is also a major industrial chemical made from coal and oil. As a pure chemical, benzene is a clear, colorless liquid. In industry,  benzene is used to make other chemicals, as well as some types of  plastics, detergents, and pesticides. It is also a component of  gasoline.

What is the Benzene Subregistry?

The Benzene Subregistry is a substance-specific part of the  National Exposure Registry. It is made up of self-reported health  information, from people throughout the United States who have  been exposed to benzene from the environment. This study investigates the health outcomes of 1,143 persons (1,127  living, 16 deceased) living in south central Texas who had  documented environmental exposure to benzene (up to 66 ppb) in  tap water. As with all subregistries, face-to-face interviews were  used to collect self-reported information for 25 general health status  questions. Using computer-assisted telephone interviewing, the  same health questions were asked 1 year (Follow-up 1) and 2 years later (Follow-up 2). The health outcome rates for baseline and Follow-up 1 and 2 data  collections for the Benzene Subregistry were compared with national norms, that is, the National Health Interview Survey (NHIS) rates.  Registrants reported some health conditions at a  higher rate than would have been expected. Some of the health  conditions were reported more frequently by certain age groups. In the case of some conditions, only men or only women had higher  rates. Cancer rates were not higher compared with those found in  the general population. Some of the health conditions with higher  rates were anemia and other blood disorders, diabetes, skin rashes, and urinary tract disorders. These results do not identify a causal relationship between benzene exposure and adverse health effects; however, they do reinforce the need to continue biennial follow-up  of registrants (as is done with the TCA and TCE Subregistries). 

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Dioxin Subregistry

What is dioxin?

"Dioxin" is a generic name used to describe a single chemical or mixture of chemicals known as polychlorinated dibenzodioxins. The most toxic form of dioxin is 2,3,7,8-tetrachlorodibenzo-p-dioxin  (2,3,7,8-TCDD). Dioxins are present in the environment primarily because of the burning of fuels, wood and waste.  They are also found at low levels in cigarette smoke. 2,3,7,8-TCDD, is found mostly in wastes from  factories making chlorinated phenols and as a byproduct of the  chlorine bleaching process used at pulp and paper mills. In the  environment, dioxins are usually found in contaminated ash or soil. They can also be found in the air, and in the sediment of industrial  run-off water.

What is the Dioxin Subregistry?

The Dioxin Subregistry is a substance-specific part of the National  Exposure Registry. It is made up self-reported health information,  from people throughout the United States who have been exposed  to dioxin from the environment. The purpose of the Dioxin Subregistry is to assess the long-term health consequences to a general population from long-term, low- level exposures to 2,3,7,8-tetrachlorodibenzo-p-dioxin (dioxin) in  the environment. Face-to-face interviews were used to collect self- reported information for 25 general health status questions. The  health outcome rates for the Dioxin Subregistry were compared with morbidity data in the National Health Interview Survey (NHIS).  The Dioxin Subregistry baseline includes 250 persons (246 living,  4 deceased) who had documented environmental exposure to dioxin. Registrants reported some health conditions at a higher rate than would have been expected. Some of the health conditions showed  higher rates for certain age groups. Others had higher rates only for men or only for women. Some of the health conditions with higher  rates are anemia and other blood disorders, skin rashes, stroke,  urinary disorders, and cancer. At first, cancer rates appeared to be higher among registrants when compared with the general population;  however, after further study the overall rate of cancer was not elevated. Two specific types of  cancer, cervical and bladder cancers, were reported more frequently  by registrants; these cancers are not among those commonly  associated with dioxin exposure. These results do not identify a causal relationship between dioxin  exposure and adverse health effects; the excess reporting of some  health conditions might be explained by methodological differences in data collection. The results do, however, reinforce the need to  continue biennial follow-up of registrants (as is done with the TCA  and TCE Subregistries). 

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1,1,1-Trichloroethane (TCA) Subregistry

Q: What is TCA?

1,1,1-Trichloroethane (TCA) is a colorless humanly produced  chemical that does not occur naturally. In the environment, it can be found as a liquid, as a vapor, or dissolved in water and other  chemicals. When found as a liquid in an open container, it evapo- rates quickly and becomes a vapor in the air. TCA has a sweet yet sharp odor. TCA is made by industry and used in commercial products. It is often used as a solvent to dissolve other substances, for example,  glue and paint. In industry TCA is widely used to remove oil or grease from manufactured metal parts. In the home, it might be used in products such as spot cleaners, glues, and aerosol sprays.

What is the TCA Subregistry?

The TCA Subregistry is a substance-specific part of the National  Exposure Registry. It is made up of  self-reported health infor- mation, from people throughout the United States who have been  exposed to TCA from the environment. Face-to-face interviews were used to collect self-reported infor- mation for 25 general health status questions. The health outcome rates for the TCA Subregistry were compared with morbidity data  in the National Health Interview Survey (NHIS). The TCA Sub- registry baseline includes 4,280 persons (4,041 living, 239 de- ceased) at a site in New York who had documented environmental exposure to TCA. Registrants reported some health conditions at a higher rate than would have been expected. Some of the health conditions showed higher rates for certain age groups. Others had higher rates only for men or only for women. Cancer rates did not appear to be elevated compared with rates in the general population; however, further  analysis of this outcome is necessary. In the baseline interview,  registrants reported the following health conditions at higher rates  than the general population:  anemia and other blood disorders,  arthritis, and urinary tract disorders.  In the Follow-up 1 interview,  registrants continued to report anemia, other blood disorders and  urinary tract disorders more frequently than the general population. These results do not identify a causal relationship between TCA ex- posure and adverse health effects; the excess reporting of some  health conditions might be explained by methodological differences  in data collection.  The results do, however, reinforce the need to  continue biennial follow-up of registrants (as is done with the TCA  and TCE Subregistries).

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Trichloroethylene (TCE) Subregistry

Q: What is TCE?

Trichlorothylene (TCE) is a colorless liquid at room temperature with an odor similar to ether or chloroform.  It is a man-made chemical that does not occur naturally in the environment.  TCE is mainly used as a solvent to remove grease from metal parts. It is used as a solvent in other ways, too, and is used as a chemical (building block) to make other chemicals.

What is the TCE Subregistry?

The TCE Subregistry is a substance-specific part of the National  Exposure Registry. It is made up of self-reported health infor- mation, from people throughout the United States who have been exposed to TCE from the environment. The purpose of the Trichloroethylene (TCE) Subregistry is to  assess the long-term health consequences to a general population  from long-term, low-level exposures to TCE in the environment.  Face-to-face interviews were used to collect self-reported infor- mation for 25 general health status questions. Using computer- assisted telephone interviewing, the same health questions were  asked during the subsequent interviews (Follow-ups 1-3). The  health outcome rates for the TCE Subregistry were compared  with health outcome morbidity data in the National Health Inter- view Survey (NHIS). The TCE Subregistry baseline includes  4,489 persons (4,172 living, 317 deceased) at sites in five  states who had documented environmental exposure to TCE. In the information collected so far, registrants reported some  conditions at a higher rate than the general population. The  health conditions reported in excess at one or more of the inter- view time periods were anemia, diabetes, hearing impairment,  hypertension, kidney disease, liver problems, skin rashes,  speech impairment, stroke, and urinary tract disorders. These  results do not identify a causal relationship between TCE ex- posure and adverse health effects; the excess reporting of some health conditions might be explained by methodological  differences in data collection. The results do, however, reinforce the need to continue the biennial follow-up of registrants. 

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Iodine-131 Subregistry

Q: Will this be a legitimate study?

Yes, the National Opinion Research Center with the University of  Chicago is under contract with ATSDR to conduct the study.

What is the study ?

The Iodine-131 Subregistry will be a part of the National  Exposure Registry. ATSDR is developing this [an iodine-131 exposure] subregistry to assess a variety of health conditions (other than thyroid disease) in a cohort of 17,000 people exposed as children under the age of 6 years during the period 1945- 1951 in a 3-county region near the Hanford Nuclear Reservation.  The mission of the Hanford Nuclear Reservation, located on 570  square miles of land in southeastern Washington State near the  cities of Richland, Pasco, and Kennewick was to produce pluto- nium. 

Will this study be associated with the Department of Energy  (DOE)?

Not directly. The connection is that DOE is required to fund the pro- ject under the Superfund legislation.

Can a family member (brother, sister, cousin, child) participate  as well?

The parameters set for the project are 1) to have been born in  Adams, Franklin, or Benton counties between 1940 and 1951  or 2) to have been born elsewhere and to have moved into one of the three counties between 1945 and 1951 when under the age of 6  years.  If they meet this criteria they are eligible to participate, and we will add their personal data to our list of persons to be contacted  when funding becomes available.  We hope funding will be avail- able soon. 

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