Trichloroethylene (TCE) Subregistry
Baseline through Followup 3
Registrant Report
The Agency for Toxic Substances and Disease Registry (ATSDR) started the Trichloroethylene (TCE) Subregistry in 1989 as part of the National Exposure Registry (NER). The goal of the TCE Subregistry is to collect and provide information that will help ATSDR explore any possible links between exposure to TCE and health problems and to keep registrants informed of all current information related to their TCE exposure. Information from the first (Baseline) interview with subregistry members (registrants) was reported to you in the spring of 1993. In 1996, ATSDR reported the findings for the Followup 1 interviews.
This report summarizes results reported in the TCE Baseline Through Followup 3 Technical Report, which provides detailed information on the survey methods and results from the first four sets of interviews: Baseline, Followup 1, Followup 2, and Followup 3. These interviews were conducted between 1989 and 1995 at different times for each of the 14 sites in five states. In addition, this report updates information contained in the registrant reports for the Baseline and Followup 1 interviews by including the results of these interviews at two new sites. The full report is available at locations listed in the cover letter.
Who are the registrants?
Registrants are persons who were exposed to TCE at 14 sites in five (5) states: Michigan, Illinois, Indiana, Arizona, and Pennsylvania. The majority (over 90%) reside in the north central United States. Information about registrants who participated in each interview is presented below.
What were the results?
Like the previous Baseline and Followup 1 reports, the health conditions reported by TCE registrants at each interview were compared with the health conditions reported by the general population in a nationwide survey. The results contained in this report are limited to registrants who reported their race as white because the number of people in other racial groups was too small to allow for meaningful analysis.
Registrants reported higher rates for certain health conditions when compared with the national survey, but the higher rates for some health conditions were not always reported at all of the interviews (Table 1). The higher reported rates were also not consistent by age and gender groups for all four (4) sets of interviews. Results and findings previously summarized in the Baseline and Followup 1 Registrant Reports may have changed due to the addition of data from the new registrants in Pennsylvania and Arizona. Also, it should be noted that the rates of all health conditions can change with time; thus, the comparisons with the national rates may also change. Overall, TCE registrants reported higher rates than the general population for certain health conditions at each interview as shown below. See Table 1 at the end of this report for details by age and sex.
| Baseline | Followup 1 | Followup 2 | Followup 3 |
|---|---|---|---|
| Anemia | Anemia | Anemia | Anemia |
| --- | Diabetes | --- | Diabetes |
| Hearing impairment | --- | --- | --- |
| --- | Hypertension | --- | --- |
| Kidney disease | --- | --- | --- |
| --- | Liver problems | Liver problems | Liver problems |
| Speech impairment | --- | --- | --- |
| Skin rashes | Skin rashes | Skin rashes | Skin rashes |
| Stroke | Stroke | Stroke | Stroke |
| Urinary disorder | Urinary disorder | Urinary disorder | Urinary disorder |
Does TCE in household water affect health?
Although registrants who were exposed to TCE in drinking water reported several health problems more frequently than the general U.S. population, the TCE Subregistry data cannot be used to determine if TCE "causes" health problems. The higher reported rates may be related to TCE exposure, but other factors might have contributed to these health problems. For example, both exposure to chemicals at work and lifestyle factors (such as smoking cigarettes and drinking alcohol) can affect health. Some health conditions can also be due to other illnesses. For instance, hearing loss can be related to ear infections.
To better understand the health conditions reported by TCE Subregistrants in this report, ATSDR needs more detailed health information. ATSDR staff members will be contacting registrants who reported having cancer to determine the exact type of cancer and whether other factors, if any, might be related to those conditions. A pilot validation study of cancer outcomes has been completed, and a separate report on cancer is in progress. An investigation of the higher reported incidence of hearing loss and speech impairment in children at the time of the baseline interview has been completed and these results will be available in 1999. Because of consistent excess reporting of these conditions by TCE registrants, more in-depth analyses of diabetes and anemia are ongoing, and additional questions about these two conditions will be asked at the next interview. Reports on the findings of all these studies will be shared with registrants.
What happens now?
ATSDR will continue to contact registrants to update TCE Subregistry files. Data from Followups 4 and 5 (including data collected in the fall of 1997) are being analyzed by ATSDR and should be provided to registrants in 2000. The time between updates is being increased from two years to three years, to reduce the time registrants spend answering questions while still enabling ATSDR to obtain valuable and timely information about registrants' health. The next series of interviews is scheduled to take place in the fall of 2000. The same questions that were asked in previous interviews will be included in this next follow-up, and some new questions may be added on the basis of the results of analyses of data already collected. The results of all future follow-ups will be shared with registrants.
What should the registrants do?
ATSDR does not have enough information about the health conditions reported by members of the TCE Subregistry to make medical recommendations for registrants that are different from those for the general public. If registrants have any concerns about their health, they should consult their personal doctors or other health care providers.
For information on this report or the TCE Baseline Through Followup 3 Technical Report, please call toll-free at 1-888-422-8737.
Summary of results of Baseline and Followups 1, 2, and 3 comparisons with NHIS
F1: Followup 1 M: Male
F2: Followup 2 F: Female
F3: Followup 3
X = Statistically significant differences (i.e., rate for the TCE Subregistry group was significantly higher
e = TCE Subregistry higher than expected (observations/expected 2.5) but not statistically significant
Agency for Toxic Substances and Disease Registry, 1825 Century Blvd, Atlanta, GA 30345
Contact CDC: 800-232-4636 / TTY: 888-232-6348
