COMMENTS/QUESTIONS for the upcoming 2003/2004 ATSDR Public Health Assessment
Introduction: ACES has two main lines of concern about past and present contamination from the WR Grace Superfund Site, one related to following up on previously identified health risk concerns, and the other to addressing newly identified potential health risks. Our concerns are detailed in Sections A. and B. below.
A. Previously Identified Health Risk Concerns, Followup Needed
The 1992 ATSDR Public Health Study was never finalized, but it began a valuable assessment by looking at cancer rates at the CENSUS TRACT level in Acton and Concord, as well as looking at the concentrations of contaminants in Acton drinking water, and in soils, sludge, and groundwater at the WR Grace Superfund Site. Both the ATSDR and John Snow Institute studies noted that cancer has long latency periods, and as the ATSDR report stated in 1992 “Sufficient time may not have elapsed to allow cancer to develop.” Since 1992, eleven additional years of data should now be available. Also in the intervening years there may have been technological and analytical advances to allow a fuller assessment of the impact of the contaminants on public health. Therefore:
1. As part of the planned 2003/2004 ATSDR Public Health Assessment of the WR Grace Site, please assess disease rates at both the census tract level in Acton and West Concord, as well as town-wide in Acton.
2. Please include in the assessment all cancers tracked by the MA Cancer Registry, paying special attention to the cancers addressed by the John Snow Institute (leukemias, bladder cancer, colorectal cancers, liver cancers, non Hodgkins lymphoma, Hodgkins disease, and all cancers combined.)
a. Please assess both cancer incidence and cancer death rates.
b. Please include all data from the earliest possible date through the present. (JSI looked at cancer mortality data in five groupings: 1969-1973, 1974-1978, 1979-1983, 1984-1986, and 1987-1988; and at cancer incidence rates from 1982-1988.)
c. Please present data in a form so that rates from different time periods can be directly compared. (The 1995-1999 data cautions about comparing different data sets from different years.)
d. Please indicate any data limitations when assessing cancer data or trends. For example the MA Department of Public Health annual report on “Cancer Incidence and Mortality in MA 1996-2000” warns that some cancers may be under-reported due to how and where they are diagnosed –ie in a hospital or not, (leukemia, multiple myeloma, etc.). Also the actual incidence rates for some cancers with shorter survival times, (including liver and pancreatic cancer), may be 10% higher than initially reported due to delay and error. Please recheck all data, (including historical data), so that any corrections for under-reporting, error, or delayed reporting are made.
3. Please extend the assessments of infant mortality and low birth weights, up to the present, and provide and analyze all of the data from 1969 to the present.
4. One limitation that has been anecdotally related about previous assessments was that Acton’s population was too small and too mobile to fully analyze the effects of the WR Grace contaminants on public health. Are there any new statistical or other analytical tools available that can now be used to overcome previous limitations? Could space-time cluster analysis or other techniques be applied? Could the remaining population of long-time residents be identified, surveyed, and assessed for health effects? If so, please help with the planning for these assessments.
5. People exposed to contaminated drinking water were exposed to several chemical contaminants together. Please assess the possible synergistic and cumulative effects of human exposures to multiple chemicals in the body.
6. The 1992 ATSDR report concentrates on the potential relationship between chemical exposure and cancer rates. Please also assess other health-related outcomes that may be related to chemical exposure. These could include: chromosomal disorders, other birth defects, multiple sclerosis, Lou Gehrig’s disease, asthma, infertility, learning disabilities, autism, rates of ADD and ADHD, other Special Education needs, etc. Can Acton’s rates of these or similar health issues be compared over time to state rates? Are there any clusters of these conditions within Acton? Could any of these health issues be related to the chemical contaminants at the WR Grace Site?
7. A 1984 ATSDR memo stated that an epidemiological study was being conducted in Battle Creek, Michigan, that could be relevant to conditions in Acton since three of the contaminants being assessed were the same as ones from the Acton site. What were the results of that study? Please provide the Acton Board of Health, ACES and the Acton Memorial Library with hard copies of that and any other relevant studies from Battle Creek or elsewhere, including any ATSDR studies of the Superfund Site in Woburn, MA.
8. Please avoid generalizations and be as precise as possible, especially when describing potential health risks. Please use statistical means to explain risk rather than undefined terms such as “significant health risk”, “significantly increased risk of cancer”, “appreciable health effect”, or “excess cancer risk”, etc.
9. Please address the question of odors and possible health effects associated with airborne contaminants from the site.
B. Newly identified Potential Health Risks
Since 1992, a plume of contaminated groundwater to the northeast of the previously defined area has been newly delineated. This northeast plume of contamination is deep under residential areas, and is migrating towards and discharging to Fort Pond Brook and to three separate Acton public drinking water wells/wellfields known collectively as the School Street Wells. Up to 190ppb of 1,1 dichloroethene (also known as VDC or DCE) was measured in this plume, as of Fall 2002. (The drinking water standard for VDC is 7ppb.) WR Grace’s August 2002 Remedial Investigation Report states that the concentrations of contaminants reaching the public wells are expected to rise in coming years as the most concentrated part of the plume is pulled towards them. The Acton Water District treats the water from these wells with a stripping tower before the water is piped to consumers.
10. Since no treatment technology is 100 percent effective 100 percent of the time, please assess the health impacts of the contaminants from this northeast plume to drinking water customers, assuming no treatment of the water. What are the worst-case potential health impacts due to exposure via ingestion, dermal exposure, and inhalation?
11. Private irrigation wells in the plume to the northeast may have brought contamination to the surface in the past. Please assess any possible health effects this past exposure may lead to. Please also assess any potential synergistic effects that may have occurred if residents were exposed to WR Grace contaminants in conjunction with lawn chemicals.
12. Please do an analogous health assessment to that done for the previous question, assuming that in the future an irrigation well were to bring the most concentrated level of contaminants to the surface, both with and without accompanying human exposure to lawn chemicals.