PUBLIC HEALTH ASSESSMENT
(a/k/a ROSEN BROTHERS SITE)
CORTLAND COUNTY, CORTLAND, NEW YORK
Summary of Contaminants Detected in Soil, Sediment, Wastes
and Groundwater During the Phase II Investigation
at and near the Rosen Brothers Site
City of Cortland, Cortland County, New York
Footnotes for Table 1.
Source: Wehran Engineering, April 1987.
Notes: The data summarized do not include tentatively identified compounds (TICs), results reported as "estimated", or found in the associated sample blank and may be indicated as "not detected."
1Refer to Figure 5, Appendix A for sample locations.
2Highest concentration reported
3Data is representative of one composite sample collected from 12 locations throughout the site. mcg/L = micrograms per liter
- indicates not detected or not reported
NA indicates not analyzed
*Contaminant selected for further evaluation.
# indicates insufficient sample for analysis
Summary of Chemicals Found in an On-Site
Soil Sample Collected in October 1985.
Rosen Brothers Site
City of Cortland, Cortland County, New York
|Source: Adapted from Blasland, Bouck & Lee
|mg/kg = milligrams per kilogram|
Summary1 of Inorganic Constituents in Groundwater
at and near the Rosen Brothers Site
City of Cortland, Cortland County, New York
Source: Blasland, Bouck & Lee (May 1994).
1This table includes only those metals at levels in groundwater that exceed NYS DOH drinking water standards and/or public health assessment comparison values (refer to Table 5).
mcg/L = micrograms per liter
* indicates that reported concentrations did not exceed NYS DOH drinking water standards and/or public health assessment comparison values.
Summary of Reported Air Emissions and Releases for
Manufacturing Facilities Near the Rosen Brothers Site
as Reported to the Toxic Chemical Release Inventory for 1993
City of Cortland, Cortland County, New York
|Contaminant Emissions (lbs/yr)|
|Bestway Enterprises, Inc.||1.9||chromium compounds
|Pall Trinity Micro Corp.||2.1||hydrochloric acid
|Potter Paint Company, Inc.||0.5||glycol ethers
methyl isobutyl ketone
|Cortland Line Co., Inc.||1.0||2-butanone
methyl isobutyl ketone
Adapted from: Toxic Chemical Release Inventory (TRI), Calendar Year 1993.
Note: All air emission data reported in pounds/year (lbs/yr).
# Indicates estimated worst case air emissions based on reported data.
- Indicates no air emissions/release data reported.
+Distance in miles
Water Quality Standards/Guidelines and/or Public Health Assessment Comparison Values that are Exceeded by Contaminants Found in Groundwater at or
near the Rosen Brothers Site City of Cortland, Cortland County, New York
[All values in micrograms per liter (mcg/L)]
|New York State||U.S. EPA|
|1,1-dichloroethene||5||0.07(g)||5||7||0.058||EPA CPF||7||EPA LTHA|
|tetrachloroethene||5||0.7(g)||5||5||0.67||EPA CPF||70||EPA RfD|
|trichloroethene||5||3||5||5||3.3||EPA CPF||52||EPA RfD|
|vinyl chloride||2||0.3(g)||2||2||0.018||EPA HEAST||0.14||ATSDR MRL|
|chloromethane||5||--||5||--||2.7||EPA HEAST||3||EPA LTHA|
|Aroclor 1254||0.1a||0.01a||0.5a||0.5a||0.005b||EPA CPF||0.14||ATSDR MRL|
|arsenic||25||50||50||50++||0.02||EPA CPF||1.1||EPA RfD|
|magnesium||35,000(g)||35,000||--||--||--||--||35,000||NYS DOH RfG|
Footnotes for Table 5.
a = Value listed applied to sum of these substances.
b = Based on oral Cancer Potency Factor (CPF) for Aroclor 1254.
g = Guidance value
l = Action level
s = Secondary maximum contaminant level (MCL)
*Comparison value determined for a 70 kg adult who drinks 2 liters of water per day.
**EPA RfD = EPA Reference Dose
EPA LTHA = EPA Lifetime Health Advisory
EPA HEAST = EPA Health Assessment Summary Tables
ATSDR MRL = ATSDR Oral Minimal Risk Level
+No designated limit; water containing more than 20,000 mcg/L should not be used for drinking by people on severely restricted sodium diets; water containing more than 270,000 mcg/L should not be used for drinking water by people on moderately restricted sodium diets.
Public Health Assessment Comparison Values that are Exceeded by Contaminants Found in Soils and Sediments at and near the Rosen Brothers Site
City of Cortland, Cortland County, New York
[All values in milligrams per kilogram (mg/kg)]
|Nonresidential Setting**||Industrial Setting***|
|benzo(a)pyrene||+||1.4||NYS DOH CPF||c||c||0.3||c|
|aroclor-1248||<0.01-0.04d||2.5||EPA CPF||12||ATSDR MRL||0.7||59|
|aroclor-1254||<0.01-0.04d||2.5||EPA CPF||12||ATSDR MRL||0.7||59|
|arsenic||10-20||13||EPA CPF||180||EPA RfD||3.5||890|
Footnotes for Table 6. ND - not determined
**Comparison values for cancer risk are determined for a 70 kg adult who ingests 50 mg soil per day, 2 days per week for 3 months per year; comparison values for noncancer risk are determined for a 21 kg child who ingests 100 mg soil per day, 5 days per week for 6 months per year.
***Comparison values for cancer risk are determined for a 70 kg adult who ingests in the work place 50 mg soil per day, 5 days per week, 8 months per year and assuming that exposure occurs for 40 working years out of a 70 year lifetime; comparison values for noncancer risk are determined for a 70 kg adult who ingests in the workplace 50 mg soil per day, 5 days per week for 8 months per year.
****EPA CPF = US EPA Cancer Potency Factor
EPA RfD = US EPA Reference Dose
EPA HEAST = US EPA Health Effects Assessment Summary Table
ATSDR MRL = ATSDR Minimal Risk Level
NYS DOH CPF = NYS DOH Cancer Potency Factor
NYS DOH RfG = NYS DOH Risk Reference Guideline
+Based on reported background levels for total polycyclic aromatic hydrocarbons of 1 to 13 mg in soil (Edwards, 1983).
aComparison value adjusted according to US EPA's interim relative potency factors for polycyclic aromatic hydrocarbons.
NYS DOH PROCEDURE FOR EVALUATING POTENTIAL HEALTH RISKS
FOR CONTAMINANTS OF CONCERN
To evaluate the potential health risks from contaminants of concern associated with the Rosen Brothers 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|
|Risk Ratio||Qualitative Descriptor|
|equal to or less than one per million||very low|
|greater than one per million to less
than one per ten thousand
|one per ten thousand to less than one
|one per thousand to less than one per ten||high|
|equal to or greater than one per 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
Intake to Risk Reference Dose
|equal to or less than the risk
|greater than one to five times
the risk reference dose
|greater than five to ten times
the risk reference dose
|greater than ten times the
risk reference dose
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
ATSDR Guidance for Assigning a
Public Health Hazard Category
The following section was not available in electronic format for conversion to HTML at the time of preparation of this document. To obtain a hard copy of the document, please contact:
Agency for Toxic Substances and Disease Registry
Division of Health Assessment and Consultation
Attn: Chief, Program Evaluation, Records, and Information Services Branch
1600 Clifton Road NE, Atlanta, Georgia 30333
Response to Public Comments
Summary of Public Comments and Responses
This responsiveness summary was prepared to address comments and questions on the draft public health assessment (PHA) for the Rosen Brothers site. The public was invited to review the draft PHA during the public comment period which ran from March 29, 1996 to May 20, 1996. We received comments from only one party. Similar comments may be consolidated or grouped together and some statements were reworded to clarify the comment. If you have any questions about this responsiveness summary, you may contact the New York State Department of Health's (NYS DOH) Health Liaison Program at the toll free number: 1-800-458-1158, extension 402.
The authors appear to imply that fencing is an adequate means of controlling exposure, disregarding plausible pathways for off-site contaminant migration. A fence does nothing to restrict off-site contaminant migration.
Several portions of the text (Summary, Pathways Analyses, Conclusions) refer to fencing around the site as a remedial measure that has been taken to restrict unauthorized access and minimize exposures to physical hazards at the site and contaminants, including PCBs,PAHs and lead, in on-site surface soils. These statements are not meant to imply that fencing is an adequate means of controlling off-site contaminant migration.
The existence of sensitive sub-populations in close proximity to the site, as in the case of Randall Elementary School and the day care center reported to be in its vicinity, as well as the probable population of children in the nearby residential area, needs more explicit consideration.
The qualitative descriptors employed in the public health implications section and Appendix C lack scientific support and are likely to be very misleading to readers. The authors should include the actual risk estimate or Hazard Index when supplying descriptors such as minimal or high.
Although quantitative risk calculations were completed to estimate health risks, it is not the intent of the PHA, which is not a risk assessment document, to provide detailed documentation of these calculations. However, Tables 5 and 6 and Appendix C provide the bases of the calculations. We assigned qualitative terms to describe these risks and define these terms in Appendix C although we recognize other qualifiers are possible.
If anyone wants additional information or has a specific question, they should call the NYS DOH's Health Liaison Program at the toll-free number 1-800-458-1158, extension 402.
The discussion of the 1995 United States Environmental Protection Agency (US EPA) evaluation of volatile organic compounds (VOCs) in groundwater affecting air quality needs to be clarified and referenced to a publicly available document. What were EPA's conclusions and have they been peer-reviewed?
The text has been revised (see Pathways Analyses, subsection D, Data Gaps) to clarify that this evaluation was completed in response to concerns of the citizen action group Clean Up Rosen Brothers (CURB) about the potential for site-related contaminants to affect adversely indoor air quality. The PHA includes a general discussion of this evaluation and is based on information in the report titled "Report of Off-Site Soil Gas Modeling for the Remedial Investigation/Feasibility Study Oversight of the Rosen Brothers Scrap Yard Site - Cortland, New York." The report was prepared by ICF Kaiser, Environment and Energy Group in August 1995. The reference list has been revised to include this report. Results of this screening evaluation indicate that adverse health effects associated with the modeled chemical concentrations would not occur. This general conclusion is included in the PHA. This screening evaluation was not peer-reviewed. The US EPA project manager for the Rosen Brothers site has indicated that this document will be included in the administrative record for the Rosen Brothers site and in the document repository established for the site.
Why is no discussion of the January 1995 baseline risk assessment and the critiques thereof included in the PHA?
The text (Background section, subsection A - Site Description and History) has been revised to reflect that a baseline risk assessment was completed as part of the remedial investigation for the site. Distinct differences exist between a baseline risk assessment that is completed as part of a remedial investigation (RI) and feasibility study (FS) for a site through the United States Environmental Protection Agency (US EPA) and a PHA that is completed through the Agency for Toxic Substances and Disease Registry (ATSDR). These differences include the types of data and information that are reviewed, the types of qualitative and quantitative evaluations that are completed and the overall purpose of the document in terms of evaluating the public health impact that a site may pose. It is not the intent of the PHA to evaluate the baseline risk assessment completed for the site. A PHA is a mechanism to provide the community with information on the public health implications of a specific site and identifying those populations for which further health actions or studies are needed.
The discussion of the October 1995 site visit needs to include a quantitative estimate of the extent to which non-vegetated areas still exist on the site, as these would be a prime source for off-site contaminant migration.
The purpose of the October 25, 1995 site visit was to evaluate current site conditions. As noted in the discussion of this site visit, the site was densely vegetated. During a previous site visit by the NYS DOH staff (October 23, 1993), several areas (i.e., "patches") at the ground surface showed no vegetation or grass cover; however, a quantitative estimate of these unvegetated areas was not made. Since these site visits were completed, additional remediation has occurred, including the removal of about 200 tons of metallic surficial debris. Therefore, a quantitative estimate of the non-vegetated areas identified at the site in the past may not accurately represent current conditions at the site. Furthermore, the degree of vegetation at the site is likely to vary seasonally.
The discussion of demographics needs to be more reflective of spatial relationships between sensitive subpopulations (e.g., schools) and the site.
The text has been revised to give a more detailed picture of the community living near the site, including sensitive sub-populations. Additionally, Figures 3 and 7 (Appendix B) show the locations of nearby schools.
The discussion of Health Outcome Data needs to reflect the severe limitations of epidemiological methods for detecting effects produced by small sites surrounded by limited populations.
The discussion of community health concerns should address more current concerns of the local community, particularly concerning the exposure potential of various remedial alternatives.
The purpose of this section of the PHA is to identify and address community health concerns related to the site. Past known community health concerns have been addressed in this PHA. Representatives of the NYS DOH attended a public meeting for the site in October 1993 and no community health concerns were raised. During the public review period for this PHA, 94 copies of the PHA were distributed to citizens within the community near the Rosen Brothers site. We received comments from one party during the public review period and no new community health concerns related to this site were raised. Since the October 1993 public meeting, the US EPA has met with representatives of the citizens action group CURB and other community members on numerous occasions. The purpose of these meetings was to provide the community with updated information about the site, provide the public with a clear explanation of technical issues related to investigations at the site and to maintain open dialogue with the community. No community concerns about the exposure potential of various remedial alternatives have been expressed to representatives of the US EPA, NYS DEC or NYS DOH.
An initial feasibility study presenting the proposed remedial alternatives for the Rosen Brothers site is under review through the US EPA. As part of the feasibility study, each of the proposed remedial alternatives is evaluated in terms of its effectiveness to protect human health and the environment. Each alternative is evaluated to determine how effectively it will reduce the toxicity, mobility and volume of contaminants at a site. The short-term effectiveness of each remedy is evaluated to determine possible effects to human health and the environment during construction and implementation of the remedy. The long-term effectiveness of each proposed remedy is also evaluated to identify possible effects to human health and the environment after the remedial action is complete. Once the feasibility study process is complete, the US EPA will present the proposed remedies and the preferred remedy for the site for public review and comment.
The comparison of sampled concentrations to public health comparison values needs to make explicit reference to exposure assumptions on which these comparison values are based on the extent to which those assumptions reasonably reflect exposure conditions at or near this site.
Exposure parameters that are used to calculate public health assessment comparison values and to determine excess lifetime cancer risk and noncarcinogenic health risks from exposure to contaminants in drinking water and soils/sediments are given in the footnote section of Tables 5 and 6, respectively.
The discussion of off-site samples refers to a number of samples as being upgradient of the site, although the only locational reference is to Figure 5 (Appendix A). All indicated locations on that figure are in such close proximity to the site that the authors incur a significant burden of proof to demonstrate that these samples were in fact upgradient.
In the last paragraph of the general discussion in the "Environmental Contamination and Other Hazards" section, we define the terms "on-site" and "off-site." For the purpose of this PHA, "on-site" refers to the area within the property boundary (i.e., the fenceline) as indicated on Figures 4 and 5 (Appendix A) and "off-site" refers to all areas outside of this property boundary. We agree that some of the sampling locations are very close to the fenceline around the site and were careful not to use the term "upgradient" to describe off-site groundwater sample locations. The text has been revised to reflect that off-site surface water and sediment sample locations are either upstream or downstream of the site.
The discussion of quality assurance and quality control (QA/QC) in the "Environmental Contamination" and Other Hazards section, discusses the details of sample control, but not the equally important issues of appropriate sampling location, particularly for "background" samples. There have been significant concerns regarding the appropriateness and adequacy of "background" sampling such that samples treated as background may in fact have been influenced by the site.
The discussion of Quality Assurance and Quality Control (QA/QC) in this PHA does address the issue of QA/QC measures with regard to sampling locations. As indicated, all sampling methods and sampling point strategies followed approved US EPA or other applicable protocols used in site characterization to ensure that the data gathered were representative of site conditions. The text has been revised to present this statement earlier in the discussion of QA/QC measures that were undertaken during the RI.
The NYS DOH is not aware of any technical concerns regarding the appropriateness of the background sampling locations. During the RI, off-site surface soil samples were collected from both industrial and non-industrial settings. These off-site sampling locations are shown in Figure 7 (Appendix A). The samples collected from an "industrial" setting were taken from properties north and east of the Rosen site. Figure 3 (Appendix A) presents a brief summary of recent and past site owners and operations at the industrial properties near the sampling locations for off-site "industrial" setting. A more detailed discussion of these properties is included in Appendix A (Volume 2 of 3) of the revised remedial investigation report (May 1994). The surface soil samples collected from a "non-industrial" setting were collected from an area southwest of the site and south of residential properties on Scammel Street. As discussed in the Exposure Pathways Analysis section, the potential for contaminants to migrate from the site to adjacent properties through surface water runoff is minimal because the Rosen site is surrounded by two creeks. Therefore, any surface water runoff from the site will likely drain into the creeks.
The discussion of completed exposure pathways does not adequately reflect the variety of exposure routes for wastes, surface soils and air. In addition to inhalation of volatiles, inhalation of particulates was highly likely.
The text has been revised (see Pathways Analyses, subsection A, Completed Exposure Pathways) to reflect that past completed exposures to site contaminants may have also occurred via inhalation of contaminated soil particulates and particulates in air.
The discussion of groundwater exposure as a potential pathway assumes that direct use of water as a potable water supply represents the only pathway of exposure. Clarification is needed as to whether the Cortland County Health Department (CCHD) permits irrigation wells in areas served by the public water supply, a common practice in other areas that can be associated with significant exposure potential. It must be firmly established that the CCHD restrictions are over all wells and not merely domestic wells before reliance is placed on these restrictions as precluding significant exposure.
The Cortland County Health Department (CCHD) only issues permits for potable water supply wells that are used for drinking, culinary and/or sanitary purposes. Irrigation wells that may be installed in areas served by the public water supply are not permitted by the CCHD. However, the CCHD has indicated that well points likely exist in residential areas near the site. These well points are believed to be used primarily for gardening. Groundwater contamination exists at the site and has been identified off-site in non-residential areas. The text has been revised to reflect that people who use irrigation wells for gardening and other non-potable purposes could be potentially exposed to site contaminants in off-site groundwater in the future. (See Pathways Analyses, subsection B, Potential Exposure Pathways). A recommendation has been included to reflect that groundwater sampling should occur, as appropriate, to evaluate the extent of contaminant migration to off-site areas, including possible impacts to existing private wells that are used for non-potable purposes in areas downgradient of the site.
The discussion of contaminated particulates in the Potential Exposure Pathways section needs to be more reflective of the fact that there can be significant dust generation from non-vegetated areas in the absence of any intrusive activity. Given the unvegetated areas observed in 1993, this pathway was almost certainly complete at some point in the past.
This portion of the text specifically discusses the potential for contaminated dusts to become airborne from uncovered (i.e., unvegetated) areas by winds blowing across the site. However, as discussed in the Background section (subsection C - Site Visit) of the PHA, the site was densely vegetated during the October 25, 1995 site visit and also during the October 6, 1996 site visit. During the October 1993 site visit, we noted that several areas, which can be described as "patches" at the ground surface, showed no vegetation or grass cover. Due to the limited size of these unvegetated areas, it is unlikely that they are sources of "significant" dust generation. However, we agree that exposure(s) to contaminated soil particulates was likely a completed exposure pathway in the past and we discuss this completed exposure in the Pathways Analyses section (subsection A - Completed Exposure Pathways) of the PHA.
The discussion of off-site soil in the Eliminated Exposure Pathways section fails to address the potential for deposition of wind-borne particulates.
The discussion of biota in the Eliminated Exposure Pathways section fails to address vegetables. Given the potential for off-site dust migration and the confirmed existence of a shallow groundwater contaminant plume off-site, local gardeners may be exposed to contamination via fruits and vegetables.
The Pathways Analysis Section (Subsection B - Potential Exposure Pathways) has been revised to include the potential for contaminants in dust and groundwater to migrate off-site and contaminate homegrown vegetables and fruits.
The discussion of off-site soil gas migration does not address exposure to contaminants in the confirmed off-site groundwater plume which subsequently volatilize into soil gas. The description of soil volatization is not supported by the analysis that precedes it.
Neither the public health implications section or Appendix C present an adequate discussion of the exposure parameters employed in generating risk estimates or hazard quotients that underlie qualitative descriptions of risk. It is therefore impossible to assess whether an adequate degree of conservationism is incorporated.
The discussion of lead in the public health implications section needs to be modified. A major research effort by US EPA has led to the conclusion that at any non-zero soil concentration for lead there is a non-zero probability that some members of the population will experience toxicity. An uptake biokinetic model is available to address this issue and is far preferable to any direct comparison of soil concentration to some reference concentration.
We agree that a biokinetic model for lead uptake is available. This model generates a probability distribution of blood lead levels for a group of children exposed to varying soil lead levels with concurrent exposure to lead from other sources (i.e., air, drinking water, diet). It is designed to estimate blood lead levels resulting from continuous daily exposure to lead rather than from trespasser or other intermittent exposures and has not yet been fully validated by the US EPA. The model predicts that at a soil lead level of 1,000 parts per million (ppm), which is approximately the 95% upper bound concentration in the surface soil on the Rosen site, children (5-7 year olds) continuously exposed would have less than a 1% probability of exceeding a blood lead level of 10 micrograms per deciliter (mcg/dL) which is the Centers for Disease Control level of concern. This prediction coupled with the relatively low potential for continuous daily exposure of children to on-site surface soils at the Rosen site indicates that the risk of adverse health effects is minimal.
In general, the discussion of inorganics in the public health implications section fails to consider the extremely long biological half-lives of these chemicals (estimates for cadmium range as high as 40 years). Given the strong evidence for prior exposures, it would only be reasonable to treat some members of the local population as a sensitive sub-population, reflecting the likelihood of an existing body burden of these contaminants.
To estimate noncarcinogenic health risks, the intake of each contaminant (i.e., inorganic contaminants) was compared to a reference dose. A reference dose is an estimate (with an uncertainty spanning perhaps an order of magnitude or greater) of a daily exposure level for the human population that is likely to be without any appreciable risk of adverse health effects. The reference dose for cadmium takes into accoount sensitive subpopulations, and is based on renal (kidney) toxicity in humans caused by accumulation of cadmium in the kidney after long-term exposure. The toxicokinetic models used to calculate this reference dose assume that cadmium has a half-life in humans of approximately 20 years.
The discussion of health outcome data needs to discuss the statistical power of the methods used. The study of leukemia and cancer may have lacked the statistical power to discover an actual effect. What is the minimal level of increased risk that the study was capable of detecting?
The power of the significance tests to detect true differences in the observed incidence of cancer and the expected incidence of cancer will depend on the number of cases expected. For example, the probability of detecting a true doubling of cancer incidence over the expected number will be 90 percent or higher when the expected number is at least 16. In the first review of leukemia incidence in Cortland City (1970-1979), the number of expected cases were 11.2 for males and 10.1 for females. The data suggest that the observed incidence of leukemia is as expected, since the number of expected leukemia cases in males and females together was 21.3, while the observed number of cases was 22. As discussed in the NYS DOH's 1991 report of the cancer incidence study for the years 1978-1987, the power of detecting a doubling was high for the total number of cancer cases for each sex and for several common cancer sites. Because the expected number of cases was low for some types of cancer, including leukemia, in the City of Cortland, moderate increases in cancer rates for these types of cancer may not have been detected.
Data presented in this report are not adequate to support the conclusion that "the site poses no apparent public health hazard".
A description of the criteria and actions for levels of the ATSDR public health hazard categories is presented in Appendix D of this PHA. The public health hazard category for a site is determined primarily by existing conditions at the site. For the Rosen Brothers site, two public health hazard categories were assigned to characterize past and existing conditions. The conclusions section of the PHA indicates that the Rosen Brothers site posed a public health hazard in the past and the basis for selecting this public health hazard category. Based on existing site conditions and the information reviewed, we determined that the site currently poses no apparent public health hazard. The basis for this conclusion is that there are no known ongoing exposures to site contaminants. However, we also recommend that additional remedial measures are needed to eliminate possible future exposures to site contaminants in on-site soils and groundwater.
The discussion of remediation of soil contaminants needs to include explicit language about measures to preclude additional off-site contaminant migration during and after remedial activities.
Consistent with the ATSDR guidelines, recommendations are given, when appropriate, to reduce exposures but not the specific actions and measures that should be implemented.