COEUR D'ALENE RIVER BASIN
PANHANDLE REGION OF IDAHO
INCLUDING BENEWAH, KOOTENAI, & SHOSHONE COUNTIES
Based on the three methodologies utilized in this health consultation and currently available data, a public heath hazard* may exist for children living at more than half of the residences sampled through FSPA06. Of particular concern are residences 12, 13, 15, 32, 39, 40, 43, 44, 46, 50, 51, 58, 62, 64, 67, 74, 76, & 77. Most of these residences have high soil and/or dust lead levels and should be considered Ahotspots@ in the basin. Approximately 50 homes had estimated doses twice the IOC and/or estimated blood leads in excess of the CDC action level of 10 µg/dl. While residences 18 and 37 do not rank high due to estimated blood lead levels, both of these residences had high concentrations of lead in drinking water samples and merit increased concern.
Use of the IOC and IEUBK model in this health consultation resulted in a higher estimate of children with elevated blood lead levels than have been seen in the State's Exposure Assessment and annual blood lead screening in the Basin (1999 Basin screening showed 16% of children age 1 - 6 to have blood lead levels greater than 10 µg/dl). This suggests the need to: 1) focus on children one to two years old, 2) match environmental lead levels with actual blood lead levels for children living at these residences, and 3) implement primary and secondary prevention activities in the Basin.
Overt health effects may not be apparent in individuals at these estimated blood lead levels, but concern is based upon findings of population based studies. Increased hazard is likely if other routes of exposure unaccounted for in these calculations, such as lead based paint, consumption of biota and recreational activities in the basin are a significant route of exposure to lead. Data suggest that children in some of these residences may be at risk for neurobehavioral and developmental effects.
Based on a combination of the methodologies used in this study no apparent public health hazard* exists for children who had estimated exposure doses less than twice the IOC and/or estimated blood leads less than the CDC action level of 10 mg/dl. Increased hazard is likely, however, if significant non-residential sources of lead or deteriorating lead based paint are present.
Significant lead levels in locations other than the residence may lead to increased blood lead levels in children that are not included by examining only residential lead levels. Places such as daycare centers and common use areas should be evaluated along with residences, and other potential exposure pathways such as ingestion of fish and home produce should be evaluated.
For those residences posing a public health hazard, the following is recommended:
1) action should be undertaken to reduce or cease exposure to contaminated soil and indoor dust (primary intervetion). Actions at some residences with the highest lead levels (e.g. Location ID's specified in the Conclusions Section) should be taken as soon as possible.
2) medical surveillance such as blood lead monitoring of all young children should be performed at these residences and continued basin-wide (see Appendix E for CDC recommended follow-up services according to blood lead level).
3) intervention programs (secondary intervention) should be continued in order to minimize lead exposure in children identified as having elevated blood lead levels.
4) where possible, a more detailed assessment of health hazard due to combined exposure to residential and other sources of lead should be conducted.
For those residences posing no apparent public health hazard, the following is recommended:
1) due to the presence of other potential sources of lead exposure, medical surveillance such as blood lead monitoring of children should be considered.
2) intervention programs should be continued in order to minimize lead exposures by children identified as having elevated blood lead levels.
3) if blood lead testing indicates a health hazard, other sources of lead should be assessed.
Environmental lead levels should be compared with actual blood lead testing for children living at these residences to identify children needing follow-up and to confirm method results.
Basin blood lead screening data should be evaluated by age.
For all homes constructed prior to 1978, care should be taken to properly maintain the paint in those homes and regular physical examination of painted surfaces should be performed to identify early signs of deterioration. Care should be taken during remodeling of these homes to limit exposure to lead based paint.
Perform a health risk evaluation of other metals present at these residences.
Perform an evaluation of all available data and multiple exposure pathways within the Coeur d'Alene Basin, which includes not only residential exposures such as in this document, but also recreational activities, ingestion of fish, schools, daycare centers, common use areas, and lead based paint.
Richard R. Kauffman,
Senior Regional Representative
ATSDR Region 10
M.S. Eva Y. Wong, M.S
ATSDR Region 10
Environmental Protection Agency (EPA), AAir Quality Criteria for Lead@, Research Triangle Park NC, 1986, Office of Research and Development, Office of Health and Environmental Assessment, Environmental Criteria and Assessment Office, EPA 600/8-83-028F
MOEE (Ontario Ministry of the Environment and Energy) ASoil, Drinking Water, and Air Quality Criteria for Lead: Recommendations to the Minister of the Environment and Energy,@ Advisory Committee on Environment Standards (ACES), Toronto, Ontario. ACES Report No. 94-02, ISBN: 0-7778-3114-7, June 1994.
MOEE, AGuidance on Site Specific Risk Assessment for Use at Contaminated Sites in Ontario. Appendix B: MOEE Human Health Based Toxicity Values,@ Ontario Ministry of the Environment and Energy (MOEE), Standards Development Branch. May, 1996.
Panhandle District Health Department (PDHD), Idaho Department of Health and Welfare, Centers for Disease Control, Environmental Protection Agency, AKellogg Revisited-1983 Childhood Blood Lead and Environmental Status Report,@ May, 1986.
Terragraphics Environmental Engineering, Inc., ASummary of Site-Specific Lead Health Data and Proposed Methods for the Coeur d'Alene Basin Human Health Risk Assessment(HHRA) for Lead@, April 12, 2000.
URS Greiner and CH2M Hill, AField Sampling Plan and Quality Assurance Project Plan for the Bunker Hill Basin-wide RI/FS Addendum No. 6 Residential Sampling to Support the Human Health Risk Assessment,@ September, 1998.
URS Greiner, ACandidates for Early Removal Action and/or Intervention Strategies Among Residential Homes in the Coeur d'Alene River Basin East of Harrison,@ Memorandum from Sharon Quiring to Sean Sheldrake and Mary Jane Nearman, May 14, 1999.
* The public health hazard category is used for sites that pose a public health hazard due to the existence of long-term exposures (>1 year) to hazardous substances or conditions that could result in adverse health effects. This determination represents a professional judgement based on critical data which ATSDR has judged sufficient to support a decision. This does not necessarily imply that the available data are complete; in some cases additional data may be required to confirm further support the decision made.
* The No Apparent Public Health Hazard category is used for sites where human exposure to contaminated media may be occuring, may have occurred in the past, and/or may occur in the future, but the exposure is not expected to cause any adverse health effects. This determination represents a professional judgement based on critical data which ATSDR considers sufficient to support a decision. This does not necessarily imply that the available data are complete; in some cases additional data may be required to confirm or further support the decision made.