PUBLIC HEALTH ASSESSMENT
SHERWIN WILLIAMS
EMERYVILLE, ALAMEDA COUNTY, CALIFORNIA
The data that CDHS reviewed for this public health assessment show that residents of the 45th Street Artists' Cooperative and the Horton Street Lofts may have been exposed in the past to levels of arsenic and lead that were of potential health concern. The period of potential exposure starts in 1974, when the Coop was created, to 1997, when the contaminated areas were cleaned up. The most likely route of exposure would have been incidental ingestion of dust while playing or gardening in contaminated areas. The contaminated areas include the Garden Area on the Coop property, and the flower beds along Horton Street that are adjacent to the Coop. Those most likely to have been exposed to this contamination include children who might have played in contaminated areas on the Coop property, and adults who may have gardened in these contaminated areas.
CDHS concludes that prior to September 1997, the Garden Area of the Coop Property, the flower beds along Horton Street adjacent to the Coop, and the Patio Area prior to addition of fresh soil constituted a public health hazard. Following cleanup of these areas by September 1997, these areas no longer pose a public health hazard.
This conclusion is based upon the assumption that those at greatest risk for adverse health effects gardened or played in the contaminated areas every day, for a period of one year or longer, and that they were exposed to the maximum concentration of arsenic and lead in the contaminated areas each time they played or gardened in that area. If those at risk played or gardened in the contaminated areas less frequently, or if they were exposed to less than the maximum concentration of arsenic and lead when they played or gardened, then the likelihood of adverse health effects decreases.
PUBLIC HEALTH RECOMMENDATIONS AND ACTIONS
The Public Health Recommendations and Action Plan (PHRAP) for this site contains a description of actions taken, to be taken, or under consideration by ATSDR and CDHS at and near the site. The purpose of the PHRAP is to ensure that this public health assessment not only identifies public health hazards, but also provides a plan of action designed to mitigate and prevent adverse human health effects resulting from exposure to hazardous substances in the environment. CDHS and ATSDR will follow-up on this plan to ensure that actions are carried out.
Actions Completed
Current Activities
Health Assessors
F. Reber Brown, Ph.D.
Research Scientist II
Impact Assessment Inc.
Consultant to Environmental Health Investigations Branch
California Department of Health Services
Marilyn C. Underwood, Ph.D.
Staff Toxicologist
Environmental Health Investigations Branch
California Department of Health Services
Jane Riggan, M.S.W.
Public Health Social Work Consultant
Environmental Health Investigations Branch
California Department of Health Services
ATSDR Regional Representatives
William Q. Nelson
Gwendolyn Eng
Dan Strausbaugh
Regional Representatives, Region IX
Agency for Toxic Substances and Disease Registry
ATSDR Technical Project Officer
William Greim
Environmental Health Scientist
Agency for Toxic Substances and Disease Registry
The Sherwin Williams Public Health Assessment was prepared by the California Department of Health Services under a cooperative agreement with the Agency for Toxic Substances and Disease Registry (ATSDR). It is in accordance with approved methodology and procedures existing at the time the public health assessment was initiated.
Technical Project Officer, SPS, SSAB, DHAC
The Division of Health Assessment and Consultation, ATSDR, has reviewed this public health assessment and concurs with its findings.
Chief, SPS, SSAB, DHAC, ATSDR
Figure 1. Map showing location of Emeryville and Sherwin-Williams site
APPENDIX C: Public Comments and CDHS Response to Public Comments
On October 19, 1998, CDHS mailed copies of the document Public Health Assessment: Evaluation of Lead and Arsenic Levels In and Near the 45th Street Artists' Cooperative and the Horton Street Lofts, Emeryville, California to members of the Sherwin-Willliams Consultative Work Group for review. Copies of this document were later placed in the office of the 45th Street Artists' Cooperative at 1420 45th Street in Emeryville, California, and in the Golden Gate Branch of the Oakland Public Library. The public comment period for this document ended on December 7, 1998.
This appendix contains the comments received from a Coop resident, a governmental regulator, and an engineering firm representing a previous owner of the 45th Street Building.
1. Comment from Coop Resident
Reber Brown gave a report, on November 9, on lead and arsenic content at various locations at the artist' coop. The study failed to take into consideration that the soil in most of the back of the 45th Street Building was substantially new, having been brought in the previous year to make a new garden. So naturally the readings were very low in these areas.
How do we assess the original soil quality in these areas and its potential deleterious effects over 20 years?
CDHS Response to comments from Coop resident
When the soils in the back of the 45th Street Building were sampled in early April 1997, they were sampled at both three inches and at two or 2.5 feet. According Levine, Fricke, and Recon, the samples collected from three inches would have been from the fresh soil, whereas the other samples were collected from two or 2.5 feet so as to be sure that original soil, and not the new soil, was evaluated. CDHS has reevaluated the potential adverse health effects for both children and adults in the Patio Area, using arsenic and lead concentrations from two or 2.5 feet. The text of this document has been updated to reflect this results of this reevaluation.
2. Comment from engineering firm representing a previous owner of 45th Street Building
These comments make suggestions regarding wording changes. Suggested changes are shown in italics.
1. Page 2, Paragraph 5: Shell Oil Company owned the property currently occupied by the 45th Street Artists' Cooperative (the Coop) until about 1969. We request that Paragraph 3 be modified so that a direct conversion in 1974 from Shell's operations to live/work studios is not implied in this report. Suggested language for your consideration (changes in italics): "The Coop facility was converted from a former industrial facility to live/work artist studios in 1974. For a period of time until about 1969, the Coop building was part Of a petrochemical research and development facility."
2. Page 13, Paragraph 2: Since, as the report states, that the "source(s) of contamination ... is not clearly understood" and the property in question has been owned and occupied by others in the past, we request that Paragraph 2 be modified to remove the reference to "Shell" by deleting the entire fourth sentence (starting with "It is not known . . . "). Alternatively, we suggest the following language for your consideration (changes in italics): "It is not known what effect, if any, that previous activities at the 45th Street Building when it was owned and/or operated by others in the past might have on contamination . . . "
CDHS Response to Comments from engineering firm representing a previous owner of 45th Street Building
These changes have been incorporated into the document.
3. Comments from governmental regulator
Comments from governmental regulator are in plain type. CDHS response to comments from governmental regulator are in italics
BACKGROUND
The Department of Toxic Substances Control (DTSC) Site Mitigation Program (SMP) has requested that Human and Ecological Risk Division provide review and written discussion of the document Evaluation of Lead and Arsenic Levels In and Near the 45th Street Artists' Cooperative and the Horton Street Lofts, Emeryville. This document was produced by the California Department of Health Services under a cooperative agreement with the United States Agency for Toxic Substances and Disease Registry (ATSDR).
In conducting this review, we will discuss the technical merits of the analysis, and do so in the context of how the DTSC evaluates similar situations. This should not be taken of a critique of ATSDR, it's mission, and the guidance issued by that agency. It is done purely for the sake of consistency of approach, where DTSC and other state and local agencies share responsibility with ATSDR on a joint project. Our comments are written below.
GENERAL COMMENTS
1. Exposure Assessment
We have a difficult time understanding the process by which exposure was assessed for carcinogens. This is for two reasons: First, the exposure pathway does not seem to fit the conceptual picture inherent in its assessment, and second, the criteria utilized was developed to be used under circumstances not matched by the situation being evaluated. As an example, the assessment of an increased lifetime cancer risk due to exposure to arsenic in flower beds (Page 19) assumes that a lifetime average daily dose can be calculated for exposures to the maximum detected concentration of arsenic (920 ppm, at a depth of 0.5 feet) in a flower bed. This is puzzling for many reasons. First, it assumes no other exposures to flower bed soils other than the one location and depth, and it is difficult to imagine how this could occur either conceptually on a single day or each day of a person's life. Second, the cancer slope factor developed for arsenic is intended to be applied to a significant fraction of a lifetime. As stated above, calculating a "risk" of 6.8 x 10-4 and interpreting it to the public as "low" risk appears to lend credibility to the scenario that an adult will go to, say, a flower box every day for 24 years and come into contact with soil at depth, and no other soils, ingesting a little bit each day. The DTSC would have a difficult time presenting such a scenario to anyone and stating that it represented useful health-related information for the public.
CDHS response to comments form governmental regulator
General Comments: Exposure Assessment
The approach that CDHS used in preparing this document was to look at two exposure scenarios per receptor population in each area; exposure to only the maximum concentration in an area (Patio Area, Garden Area, flower beds adjacent to 45th Street Building, flower beds adjacent to Coop Annex), and exposure to the average concentration of contamination in one each of these areas. Admittedly, exposure to only the maximum concentration of a contaminant in a given area for an extended period of time is unrealistic. However, this was included as an absolute worst case scenario. Exposure to the average concentration of a contaminant in an area more closely approximates a person's exposure to all of the soils in an area, not just at the location of maximum contamination, and is a more realistic exposure scenario. However, even this scenario is conservative, in that it assumes daily exposure for a period of greater than one year.
This comment also raises the question of calculating an increased lifetime cancer risk, using a qualitative descriptor for this value (very low, low, etc.), and the idea that a cancer slope factor is "intended to be applied to a significant fraction of a lifetime." The average lifetime used in calculating the increased lifetime cancer risk is 70 years. It is CDHS's understanding that there are several residents of the Coop who have lived at the Coop for approximately 20 years or longer, which CDHS considers to be a significant faction of a 70 year lifetime. CDHS believes that it is not unreasonable to calculate an increased lifetime cancer risk for a period of 24 years, which is the length of time the Coop has been in existence. It should be noted that the increased lifetime cancer risk that CDHS calculated is "pro rated" to account for an exposure of 24 years out of a 70 year lifetime. CDHS does not understand how the use of a qualitative description for a quantitative value lends or denies credibility to an exposure scenario.
2. Background Concentrations
It has been the experience of this Division, working in conjunction with your Program, that many inorganic soil constituents exist at detectable concentrations throughout the San Francisco Bay Area. Such is the case for arsenic, which the document under review states exists at a background concentration of 4 ppm (Page 16).
Our experience has shown that arsenic "background" is a range of concentrations, from 1 to 97 ppm nationally, and conservatively estimated to be 0.59 to 11 ppm in California. In the Bay Area, soils not impacted by any human activity often exceed this, with "background" levels near 19 ppm at some locations(Protocol for Determining Background Concentrations of Metals in Soil at Lawrence Berkeley Laboratory (LBNL) dated August 1995).
If this exercise is part to present health information to persons working or near the Sherwin-Williams facility, it is difficult to see the utility of calculating lifetime excess cancer risk to children from concentration of arsenic averaging 7.7 ppm in the Garden Area (Page 21). We do not recommend evaluating site-related risk for purposes of remedy selection by evaluating background. Background levels of other carcinogens (e.g. hexavalent chromium, beryllium) also present hypothetical risks and singling out background arsenic is misleading.
CDHS response to comment from governmental regulator
General Comments: Background Concentrations
The comments regarding the background concentration of arsenic in the San Francisco Bay Area are well taken, and identifying the reference (Protocol for Determining Background Concentrations of Metals in Soil at Lawrence Berkeley Laboratory (LBNL), dated August 1995) is also very helpful. Others have also brought this reference to our attention as being a useful reference for estimating background concentrations of metals in Bay Area soils. CDHS was not aware of this document when this Public Health Assessment was prepared.
Revising the background concentration of arsenic from 4 ppm to 14 does not affect CDHS's calculations regarding potential adverse health effects for residents of the Coop. However, it does change CDHS's general discussion of the situation. Appropriate changes have been incorporated into the text of this document.
Concerning the evaluation of contaminants that are present at concentrations comparable to normal background concentrations of that contaminant: the presence of a chemical at background concentrations does not necessarily imply that there is no risk of adverse health effects due to exposure to that chemical. The term "background" does not mean "without risk." Nor does CDHS mean to imply that arsenic and lead are the only chemicals that may be of potential health concern to the Coop residents. The reviewer is correct in that other species may be present that could potentially be of concern. However, as was discussed in the Summary Section, this document is not designed to be an exhaustive investigation of all risks, but rather only of arsenic and lead.
3. Lead
The document under review refers to a "California Preliminary Remediation Goal" (PRG) of 130 ppm for lead (page 10). Please note that this numerical standard was removed from our own Preliminary Endangerment Assessment Guidance Manual by an errata sheet developed in you own office and distributed statewide.
We have attempted to duplicate some of the predicted blood lead levels depicted in the report using the DTSC Lead Risk Assessment Spreadsheet the report references. Again, conceptual difficulties arise. Take for example the following statement on Page 18 of the report under review:
At an average concentration of 23.9 ppm, the predicted blood lead for a child exposed to lead through incidental ingestion of contaminated soil in the Patio Area would have been 4.3 µg/dL.
This statement contains two errors, one factual, and one conceptual. The DTSC Lead Risk Assessment Spreadsheet does not circulating concentrations for "a child" but for a percentage of the population, this is why the outputs are expressed as percentiles. In any case we cannot duplicate the reported model outputs, leaving on all the standard default assumptions for lead in air and water a concentration of 23.9 ppm lead in soil predicts a circulating lead level of 4.3 µg/dL in the 99th percentile of adults, not children.
Conceptually, the model used was intended to be applied in a residential setting. Is it plausible that a young child would be playing every day in the patio area as if it were a backyard?
CDHS response to comment from governmental regulator
General Discussion: Lead
Regarding the use of 130 mg/kg as the standard value for the California Preliminary Remediation Goal (PRG), the errata sheet that the reviewer mentions was not developed in our office, and CDHS was unaware of this document, which is dated June 10, 1998. However, we have received a copy of this errata sheet, and have updated the text of this document to reflect the changes indicated.
Concerning the factual error (example on page 18 of the document), the output of the DTSC Lead Risk Assessment Spreadsheet, BLOODPB.XLS, includes adults, children, pica children, and industrial workers. However, the comment that the calculated blood lead level reflects that of a percentage of the population is well taken, and the text of this document has been corrected to reflect this. Concerning the inability to reproduce the model's output, CDHS considered only lead ingestion from soil, not from any other sources. CDHS also used ATSDR default values for soil ingestion rate and water ingestion rate rather than the default values used by DTSC.
With these concerns in mind, CDHS reran the BLOODPB.XLS model using DTSC default values, with the exception of soil and water ingestion rates, where ATSDR default values were used, and the concentration of lead in air. The concentration of lead in PM10 at the San Leandro sampling station, obtained from California Air Resources Board, was used for this value. The text of this document has been changed to reflect the recalculated blood lead levels, and a sample of the output of the model has been included (Table 9).
Regarding the conceptual plausibility of this scenario: this is not a residential setting, and the children in the Coop do not have backyards in which to play. It seems to CDHS to be completely reasonable to assume that children without backyards would play in the Patio Area as if it were a backyard.
Comment from governmental regulator
CONCLUSIONS
Bearing in mind that the ATSDR has a different mission than the, DTSC, the conceptual framework under which we operate should be similar. This Division would not predict lifetime excess cancer risks or noncancer health hazard in a manner similar to the report under review. We would question the benefit to the public audience of assessing essentially background conditions for the chemical of concern, as we understand the concern to be the proximity of the Sherwin-Williams facility, and past waste disposal practices.
