HEALTH CONSULTATION
LEHIGH VALLEY RAILROAD
LEROY, GENESEE COUNTY, NEW YORK
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New York State Department of Health To evaluate the potential health risks from contaminants of concern associated with the
Lehigh Valley Road Derailment site, the New York State Department of Health assessed
the risks for cancer and noncancer health effects.
Increased cancer risks were estimated by using site-specific information on exposure
levels for the contaminant of concern and interpreting them using cancer potency
estimates derived for that contaminant by the US EPA or, in some cases, by the NYS DOH.
The following qualitative ranking of cancer risk estimates, developed by the NYS DOH,
was then used to rank the risk from very low to very high. For example, if the qualitative
descriptor was "low", then the excess lifetime cancer risk from that exposure is in the range
of greater than one per million to less than one per ten thousand. Other qualitative descriptors are listed below:
Excess Lifetime Cancer Risk
Figure 1. Lehigh Valley Railroad Derailment Site
Figure 2. Lihigh Valley Railroad Derailment Site
Procedure for Evaluating Potential Health Risks
for Contaminants of Concern
| Risk Ratio | Qualitative Descriptor |
| equal to or less than one in a million | very low |
| greater than one in a million to less than one in ten thousand |
low |
| one in ten thousand to less than one in a thousand |
moderate |
| one in a thousand to less than one in ten |
high |
| equal to or greater than one in ten | very high |
An estimated increased excess lifetime cancer risk is not a specific estimate of expected cancers. Rather, it is a plausible upper bound estimate of the probability that a person may develop cancer sometime in his or her lifetime following exposure to that contaminant.
There is insufficient knowledge of cancer mechanisms to decide if there exists a level of exposure to a cancer-causing agent below which there is no risk of getting cancer, namely, a threshold level. Therefore, every exposure, no matter how low, to a cancer-causing compound is assumed to be associated with some increased risk. As the dose of a carcinogen decreases, the chance of developing cancer decreases, but each exposure is accompanied by some increased risk.
There is general consensus among the scientific and regulatory communities on what level of estimated excess cancer risk is acceptable. An increased lifetime cancer risk of one in one million or less is generally considered an insignificant increase in cancer risk.
For noncarcinogenic health risks, the contaminant intake was estimated using exposure assumptions for the site conditions. This dose was then compared to a risk reference dose (estimated daily intake of a chemical that is likely to be without an appreciable risk of health effects) developed by the US EPA, ATSDR and/or NYS DOH. The resulting ratio was then compared to the following qualitative scale of health risk:
Qualitative Descriptions for
Noncarcinogenic Health Risks
|
Ratio of Estimated Contaminant |
Qualitative Descriptor |
|
equal to or less than the |
minimal |
|
greater than one to five times |
low |
|
greater than five to ten times |
moderate |
|
greater than ten times the |
high |
Noncarcinogenic effects unlike carcinogenic effects are believed to have a threshold, that is, a dose below which adverse effects will not occur. As a result, the current practice is to identify, usually from animal toxicology experiments, a no-observed-effect-level (NOEL). This is the experimental exposure level in animals at which no adverse toxic effect is observed. The NOEL is then divided by an uncertainty factor to yield the risk reference dose. The uncertainty factor is a number which reflects the degree of uncertainty that exists when experimental animal data are extrapolated to the general human population. The magnitude of the uncertainty factor takes into consideration various factors such as sensitive subpopulations (for example, children or the elderly), extrapolation from animals to humans, and the incompleteness of available data. Thus, the risk reference dose is not expected to cause health effects because it is selected to be much lower than dosages that do not cause adverse health effects in laboratory animals.
The measure used to describe the potential for noncancer health effects to occur in an
individual is expressed as a ratio of estimated contaminant intake to the risk reference
dose. If exposure to the contaminant exceeds the risk reference dose, there may be
concern for potential noncancer health effects because the margin of protection is less
than that afforded by the reference dose. As a rule, the greater the ratio of the estimated
contaminant intake to the risk reference dose, the greater the level of concern. A ratio equal to or less than one is generally considered an insignificant (minimal) increase in risk.
Public Health Hazard Categories
| Category | Definition | Criteria |
| A. Urgent public health hazard | This category is used for sites that pose an urgent public health hazard as the result of short-term exposures to hazardous substances. | |
| B. Public health hazard | This category is used for sites that pose a public health hazard as the result of long-term exposures to hazardous substances. | |
| C. Indeterminate public health hazard | This category is used for sites with incomplete information. | |
| D. No apparent public health hazard | This category is used for sites where human exposure to contaminated media is occurring or has occurred in the past, but the exposure is below a level of health hazard. | |
| E. No public health hazard | This category is used for sites that do not pose a public health hazard. |
Summary of Public Comments and Responses
This responsiveness summary was prepared to address comments and questions on the draft Health Consultation for the Lehigh Valley Railroad Derailment site. The public was invited to review this document during the public comment period which ran from May 20, 1997 to July 7, 1997. Comments were received from six parties. Similar comments were consolidated or grouped together. Some statements were reworded to clarify the comment. If you have any questions about this responsiveness summary, contact the New York State Department of Health (NYS DOH) Health Liaison Program at the toll-free number 1-800-458-1158, extension 6402.
Comment #1
The title of the document (cover page) suggests that it was prepared for Genesee County only. It is suggested that the title on the cover be revised to read Health Consultation for the Town of LeRoy, Genesee County; Village of Caledonia, Livingston County; and the Village of Mumford, Monroe County.
Response #1
The Heath Consultation is for the Lehigh Valley Railroad Derailment site which is located in the Town of LeRoy, Genesee County. The title on the cover of the document has been reformatted to clarify this point.
Comment #2
It is suggested that the phrase "was migrating" be replaced with "had migrated" in the fifth sentence of the third paragraph on page 3.
Response #2
The text was revised as suggested.
Comment #3
The third paragraph on page 3 states that the US Environmental Protection Agency (USEPA) installed granular activated carbon (GAC) treatment systems on 35 water supplies. The fourth paragraph on page 3 states that GAC treatment systems have been installed on 38 water supply wells. Which number is correct? Who installed the CAG systems on the other 3 wells?
Response #3
GAC treatment systems have been installed on 38 water supplies. The USEPA initially installed GAC treatment systems on 35 water supplies. Subsequently, the NYS DEC installed treatment systems on 3 additional water supplies. This clarification has been added to the text.
Comment #4
Staff from the Livingston County Department of Health did not visit "the site", per se, on a quarterly basis (page 4), but did participate in sample collection at residences in Livingston County.
Response #4
The text was revised in response to the comment.
Comment #5
On pages 5, 6 and 7, it is suggested that the phrase "about 20 years" be replaces with "20 years" when referring to the maximum duration of time that persons may have been exposed to site-related contaminants in their drinking water.
Response #5
The magnitude and duration of past exposure to site-related contaminants in drinking is uncertain. The spill occurred in December, 1970 and treatment systems were installed in December, 1991 (21 years later). The levels of contamination prior to the initial sampling (1989 to 1991) are not known. Given these uncertainties, an estimate of "about 20 years" is believed to be reasonable.
Comment #6
In the discussion of Community Health Concerns and Current Issues (page 6), bottled water was provided to people whose wells contained trichloroethene above the NYS DOH drinking water standard until treatment systems were installed.
Response #6
The text was revised in response to the comment.
Comment #7
In the Conclusions (page 7), replace "20-25 years" with "20 years."
Response #7
The text was revised to indicate that exposures have occurred for possibly as long as "about 20 years." See also Response #5.
Comment #8
The involvement of NYS DOH has been great for our area. The unexpected contamination of our wells, after such a long time from the spill, has brought a new awareness to not take our environment for granted or misuse it for those people who follow us.
Response #8
The comment is appreciated.
Comment #9
It is reassuring to know that the risk of getting cancer from our water has not increased greatly but there is still a concern as our son, daughter-in-law, and grandchildren use our water supply for drinking.
Response #9
A treatment system was installed at the commentor's residence in December, 1991 to mitigate exposure and health risk. The public water line extension described by NYS DEC in the March 28, 1997 Record of Decision (ROD) for the Lehigh Valley site, will permanently dissociate the residence from the contaminated water.
Comment #10
Is there any evidence that exposure to trichloroethene or cis-1,2-dichloroethene could cause gallbladder or kidney stones?
Response #10
A search of the scientific literature did not reveal evidence of an association between exposure to trichloroethene or cis-1,2-dichloroethene and gallbladder or kidney stones.
Comment #11
Two individuals requested that their wells be sampled.
Response #11
Staff of the NYS DOH contacted the requestors to discuss their concerns and to schedule sampling. One residence was sampled in July, 1997. The other will be sampled during the next round of sampling in October.
Comment #12
I am pleased with your recommendations and plans to alleviate future health problems and communicate with the involved population. Please continue. Further evaluation of long-term ingestion is needed.
Response #12
The comment is noted.
Comment #13
Have studies been conducted on the fish in Spring Creek? It is a popular fishing site.
Response #13
During the remedial investigation, contamination was documented in springs and groundwater near Spring Creek. However, samples of water collected directly from the creek showed trichloroethene at either non-detectable levels or at very low levels (less than the NYS DEC surface water guidance value for the protection of human health from consumption of fish). This is most likely due to the extensive dilution in Spring Creek. Similarly, only minor amounts of trichloroethene were detected in the creek sediment in the area of the springs. In addition, no ill effects have been reported at the NYS DEC fish hatchery in Caledonia which uses water from Spring Creek for its fish propagation operations. Based on the above, it was concluded that trichloroethene would not be found at levels of public health concern in fish in Spring Creek. The Health Consultation does, however, contain a recommendation to continue monitoring the impact on Spring Creek during and after construction of the remedial plan.
Comment #14
Mud Creek is mislabeled as Mad Creek in Figure 2.
Response #14
Figure 2 was revised to correct the typographical error.
