Love Canal Follow-up Health Study - August 2003

Study Plan and Progress

August 2003

Getting ready for serum results

The Love Canal follow-up health study uses comparison neighborhoods in the analysis with the exception of the serum analysis project. We are not collecting and analyzing new serum samples from non-Love Canal residents to compare with the results from the stored serum from Canal residents. Collecting a comparison sample now would be of little use because we would be taking a sample now to compare to a sample almost 25 years old. However, we will look at comparison data in the literature that may help us understand the data from Canal residents.

The serum was collected in 1978 for testing. Any leftover material had been stored in the Wadsworth Laboratory. We consulted with the Expert Advisory Committee about chemical analysis of the remaining sera. The Committee helped us to decide upon testing individual's serum for

We often tell residents at other sites who are concerned about past exposures that we can't go back in time and take a sample of their water, air or soil to measure exposure. Analyzing the stored sera for possible Love Canal chemical exposures is an extremely rare opportunity to go back in time. Sera samples are even better than taking an air or water sample for understanding body burden levels.

  • At best, serum LCIC concentrations are a snapshot of an earlier time of exposure.
  • The LCIC levels themselves don't represent exposure to every Love Canal chemical; the LCICs were chosen as indicators of exposure to the mix of Love Canal chemicals.
  • Each person's concentration can be compared to results for other Canal residents.
  • Some LCICs are stored with fat in the blood, so the levels will be higher or lower depending upon how much fat was in the stored serum sample. If the person had fasted before giving the blood sample, he or she might have lower levels than if they had eaten just before blood was taken. We will provide the lipid (fat) content when we report the results and calculate what this difference would make for each individual's levels.
  • When we send out results, we won't be able to provide information about individual health risks from the serum concentrations. The LCICs are indicators of Love Canal chemical exposure.
  • As part of our future work, we will compare the group of LCIC measurements to see if those who had higher concentrations were more likely to have experienced health effects and report findings in a future newsletter.

You responded to our request for help once again!

We asked people for whom we had stored serum for permission to analyze it for LCICs. With just one mailing and the reminder in the newsletter, enough people provided permission to move forward. This means that we will be able to learn about chemical levels in people living in each of the rings, representing each age group and from both genders. It will not be necessary to mix samples together before analyzing them.


<Special Thanks to Our Readers

In 1998 we held our first Expert Advisory Committee meeting— That's five years ago. Although looking back it seems the time went quickly. When we began the study, we planned a five to six year project developed by DOH. With the Committee's guidance and input from former residents, we've changed the study plan. We expanded the study in some areas and cut back on things that you said were not important. We tried to gather the information you said was really important to you, such as including 99th Street school children.

We've passed the study's completion date and we are eager to finish and get the results to you. Of course, the scientific aspects of the study are important and we've tried to keep you involved with decisions and informed about findings as we go along. The individual blood sera have been analyzed and we can begin the work of interpreting that data set. The mortality study report is being written, and we're busy finishing the cancer study before moving on to the reproductive study portion of this effort. We just received a six-month extension to use the remaining funds for the study. This allows us to continue our present staffing level until April, 2004. There is still much work to be done. We've been considering seeking additional funding so that we can dedicate more staff to the project and finish the study quickly.

As community liaison, I often serve as a "go-between" for the Department (scientific and policy perspectives) and the community (residents who stayed, those who left, and their children and grandchildren who may have never lived near the Canal). From my perspective, I've seen significant progress made in the past five years not just on the scientific part of the study, but in the way we as people relate to each other and in the way study decisions are made. I recognize and appreciate the efforts of our researchers. However, I continue to be reminded at every phase of the project that I've had the honor of working with a compassionate and caring group of residents. You've helped redesign the study. You've used your precious free time to attend meetings, send us e-mails, letters and faxes. You responded to our surveys and our requests for permission, information and participation. You told us how you felt about the study and risked getting involved again in an issue that you worked very hard to put behind you. When we asked for this, you did it! And I believe we're all working hard to maintain a collaborative working relationship. It takes work from all perspectives involved to continue this important dialogue about the study. But I believe the greatest credit is to you, our reader. You've shown your willingness to give us a chance to work with you, and I really appreciate that.

Thanks,

Charlene

New York State is trying to cut printing and postage expenses. If you have internet access, we can move you from the mailing list to our new electronic newsletter list. Just e-mail us at ceheduc@health.state.ny.us with "Love Canal Newsletter E-mail List" in the subject line. We'll make a distribution list of e-mail addresses and notify you when the newsletter is posted on the DOH web site.

We'll post them when they are sent for printing, so you'll get the news on-line about when the printed versions would arrive in your mailbox.

If you do not have internet access or prefer to continue getting printed newsletters, there is no need to do anything. You will remain on the mailing list unless you request otherwise, or your newsletter is returned to us without a forwarding address.

Also, if you do not want the newsletter, please let us know and we'll remove you from our mailing list.

Sign up for an E-mail Newsletter by sending an e-mail to ceheduc@health.state.ny.us please put the folowing in the SUBJECT line, "Love Canal Newsletter E-mail List".

NYS Department of Health
Center for Environmental
Health

Charlene (Thiemann) Spampinato

518-402-7530

ceheduc@health.state.ny.us

Flanigan Square
547 River Street, Rm. 316
Troy, NY 12180-2216

October Meeting Highlights

We've been working on study tasks suggested by the Committee and residents — for example, our original study plan involved looking at reproductive outcomes of Love Canal women. Some residents felt very strongly that Love Canal men should also be included in this part of the study. In this case, our efforts were futile — the data from our Vital Records Bureau were not complete enough to allow us to match their records to Love Canal residents. Nor did mailings and a follow-up newsletter article result in a large enough participation for us to be able to analyze these data. Throughout the study process, we've received many well-reasoned suggestions from the Committee and residents, and incorporated as many of them as we could. But we must now stop gathering data and focus our efforts on analyzing the information we have and preparing reports.

We presented modeled cancer and mortality results to the Committee in October and obtained its advice about what other analyses to perform, and how to structure the final reports. The mortality results are ready for final reporting. The Committee concluded that our grouping of cancer sites to increase power was done well. There was discussion about choosing a comparison group for cancer incidence from a less industrialized area of western New York. There are currently two comparison groups — New York State (except for the five counties of New York City) and Niagara County. The concern was expressed that a less industrialized county might have lower cancer rates. Not everyone agreed that a third comparison group is appropriate. However, we hope to accomplish the task of looking at another county and will report on our progress at the fall meeting (see

The Committee had suggestions about when and how to present the individual serum results to participants. They agreed that we should send all the individual results at the same time, so participants will be able to see where their results fall within the range of all other values measured. We need not wait until researchers interpret the entire data set. The Committee also suggested that we avoid sending too much background and interpretative information with the sera results, but instead use the newsletter to provide the necessary background.

Wadsworth Laboratory finished its task of analyzing the sera for Love Canal Indicator Chemicals (LCICs). They are now reviewing data from a special study to learn more about the effect of a possible freeze-thaw cycle on LCIC concentrations in stored sera. The Committee suggested that the freeze/thaw study be peer reviewed by independent laboratory specialists. We asked the two reviewers who helped us earlier in the study, and they agreed to review the results. We will update you when it is completed.

We updated the Committee about our progress on the reproductive health study. This part of the study is still in the data collection phase, and we are trying to gather as much information as we can without further delaying the study. We discussed problems associated with data collection, such as difficulties in obtaining information from certain hospitals. While we move toward completion of reports on cancer and mortality, we will continue to gather additional sera and reproductive data previously identified as important to former residents, if we can do so without delaying the study.

Comparison Neighborhoods in Epidemiology Studies

In the Love Canal Follow-up Health Study, we are looking at deaths and cancer as well as some aspects of reproductive outcomes (birth weight, gender, pregnancy term, etc.) among former Canal residents. These data are then compared to the same information about another group of people who did not live at the Love Canal. Any differences observed could be due to chance, other factors, or the Love Canal exposure.

Health outcomes in a group depend on things like the ages, gender, ethnicity, income and location of the people included in the group. A well-matched comparison group (similar to the study group in as many of these ways as possible) helps in interpreting any differences seen.

If the groups are pretty much alike in the factors that impact disease rates, we can rule out these factors as the reason for the differences. Even if we don't have a close match, we can use what we know about the comparison group, such as age and gender, to adjust the information about what we expect. We cannot adjust for factors such as medical facilities, overall environmental quality, population and socioeconomic distribution because these data are not available from the registries that we are using in the study. We try to choose a comparison population whose health outcomes can be tracked. We want this group to be as similar as possible to the study group on factors that affect disease, except for the exposure being studied, so we can measure the effect of any exposure on disease.

One of the strengths of using a disease registry in a health study is that it comes with a built-in comparison group. Researchers can use the registry to pull out information about how many people in the study group have the health effect being studied, and can also get the same for any other region included in the registry. State rates are very stable because they are based on large populations. State rates are also useful because they won't change because of local or regional patterns. County rates for the county in or near the study area are also useful. They tell us something about those local differences that we won't have when looking at state rates. By looking at both state and county rates, researchers have a clearer picture of the differences and similarities, which gives them more confidence in their findings.

In the Love Canal health study, researchers decided to compare Love Canal cancer and mortality rates to New York State and to Niagara County rates. The Love Canal population is very similar to Niagara County in many ways that affect the rate of disease — the overall environmental quality, medical facilities, ethnicity, socioeconomic factors, availability of employment, and many other factors that make the two groups similar. If there is a difference between Love Canal residents and the rest of Niagara County in disease rates, the difference could be associated with exposure to chemicals from the Love Canal rather than those other factors.

Some have expressed concern that choosing Niagara County as a comparison neighborhood is not appropriate because of the industrial nature of the area, including factory emissions to air and water, and the number of hazardous waste landfills. They are concerned that Niagara County might already have an elevated rate of cancer or mortality due to possible chemical exposures, so an elevated rate among Love Canal residents might be missed. We plan to address this concern by looking for another group against which to measure Love Canal cancer rates. However, any observed differences in disease rates may be more difficult to interpret depending on differences between the groups in factors other than residence at Love Canal.

Understanding the Love Canal Treatment Facility

<Canal wastes surfaced and contaminated groundwater from the Love Canal overflowed its underground, bathtub-like enclosure. Rain water and surface water seeped into the waste disposal area from the top at a faster rate than it could move downward. The soils below are primarily clay, which blocks water flow, like a clogged drain in a tub. The water level rose inside the bathtub-like area and became contaminated from the waste materials in the landfill. When the tub became full, it overflowed.

How the treatment system works

A cap made of clay and lined with heavy grade plastic is installed over the top of the landfill to preventrainwater from entering the "bathtub." A system of barrier drains was built around the Canal. These fourfootwide trenches are 15 to 20 feet deep and completely surround the "bathtub" or landfill. Contaminatedgroundwater (also called leachate) flows through a series of "lateral drains" into the barrier drains. Thebarrier drains are lined with tile and filled with gravel to enhance drainage. The leachate drains into wetwellsthat are pumped into underground storage tanks and treated on-site. The treatment facility has apermit to discharge the treated water into the City of Niagara Falls sanitary sewer system. The system hassuccessfully prevented water migration from the Canal. Leachate entering and leaving the treatmentfacility is tested periodically, and water from monitoring wells around the area also is tested.

picture showing Leachate Storage for South Sector and surrounding area