Appendix H: Public Health Conclusion Categories

CATEGORY 1 : URGENT PUBLIC HEALTH HAZARD

This category is used for sites where short-term exposures (< 1 yr) to hazardous substances or conditions could result in adverse health effects that require rapid intervention.

This determination represents a professional judgement based on critical data which ATSDR has judged sufficient to support a decision. The assignment of this category 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.

Criteria

Evaluation of available relevant information* indicates that site-specific conditions or likely exposures have had, are having, or are likely to have in the future, an adverse impact on human health that requires immediate action or intervention. Such site-specific conditions or exposures may include the presence of serious physical or safety hazards, such as open mine shafts, poorly stored or maintained flammable/explosive substances, or medical devices which, upon rupture, could release radioactive materials.

* Such as environmental and demographic data; health outcome data; exposure data; community health concerns information; toxicologic, medical, and epidemiologic data.

ATSDR Actions

ATSDR will expeditiously issue a health advisory that includes strong recommendations to immediately stop or reduce exposure to mitigate the health risks posed by the site. The recommendations issued in the health advisory and/or public health assessment should be consistent with the degree of hazard and temporal concerns posed by exposures to hazardous substances at the site.

Based on the degree of hazard posed by the site and the presence of sufficiently defined current, past, or future completed exposure pathways, one or more of the following public health actions also may be recommended:

• biologic monitoring
• biomedical testing
• case study
• epidemiologic study
• community health investigations
• registries
• public health surveillance
• cluster investigation
• health statistics review
• health professional education
• community health/stress education
• substance-specific applied research

CATEGORY 2: PUBLIC HEALTH HAZARD

This category is used for sites that pose a public health hazard due to the existence of long-term exposures

(> 1 yr) to hazardous substances or conditions that could result in adverse health effects.

This determination represents a professional judgement based on critical data that ATSDR has judged sufficient to support a decision. The assignment of this category 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.

Criteria

Evaluation of available relevant information* suggests that, under site-specific conditions of exposure, long-term exposures to site-specific contaminants have had, are having, or are likely to have in the future, an adverse impact on human health that requires one or more public health interventions. Such site-specific exposures may include the presence of serious physical hazards, such as open mine shafts, poorly stored or maintained flammable/explosive substances, or medical devices which, upon rupture, could release radioactive materials.

*Such as environmental and demographic data; health outcome data; exposure data; community health concerns information; toxicologic, medical, and epidemiologic data.

ATSDR Actions

ATSDR will make recommendations to stop or reduce exposure in a timely manner to mitigate the health risks posed by the site. The recommendations issued in the public health assessment should be consistent with the degree of hazard and temporal concerns posed by exposures to hazardous substances at the site. Actions related to the recommendations may have occurred before the actual completion of the public health assessment.

Based on the degree of hazard posed by the site and the presence of sufficiently defined current, past, or future completed exposure pathways, one or more of the following public health actions also may be recommended:

• biologic monitoring
• biomedical testing
• case study
• epidemiologic study
• community health investigations
• registries
• public health surveillance
• cluster investigation
• health statistics review
• health professional education
• community health/stress education
• substance-specific applied research

CATEGORY 3: INDETERMINATE PUBLIC HEALTH HAZARD

This category is used for sites when a professional judgement on the level of health hazard cannot be made because information critical to such a decision is lacking.

Criteria

This category is used for sites in which "critical" data are insufficient with regard to extent of exposure and/or toxicologic properties at estimated exposure levels. The health assessor must determine, using professional judgement, the "criticality" of such data and the likelihood that the data can be obtained and will be obtained in a timely manner. Where some data are available, even limited data, the health assessor is encouraged to the extent possible to select other hazard categories and to support their decision with clear narrative that explains the limits of the data and the rationale for the decision.

ATSDR Actions

ATSDR will make recommendations in the public health assessment to identify the data or information needed to adequately assess the public health risks posed by the site.

Public health actions recommended in this category will depend on the hazard potential of the site, specifically as it relates to the potential for human exposure of public health concern. Actions related to the recommendations may have occurred before the actual completion of the public health assessment.

If the potential for exposure is high, initial public health actions aimed at determining the population with the greatest risk of exposure can be recommended. Such public health actions may include:

• community health investigation
• health statistics review
• biologic monitoring
• environmental sampling
• cluster investigation
• epidemiologic study

If the population of concern can be determined through these or other actions, any of the remaining follow-up health actions listed under categories 1 and 2 may be recommended.

In addition, if data become available suggesting that human exposure to hazardous substances at levels of public health concern is occurring or has occurred in the past, ATSDR will reevaluate the need for any follow-up actions or activities.

CATEGORY 4: NO APPARENT PUBLIC HEALTH HAZARD

This category is used for sites where human exposure to contaminated media may be occurring, may have occurred in the past, and/or may occur in the future, but the exposure is not expected to cause adverse health effects.

This determination represents a professional judgement based on critical data that ATSDR considers sufficient to support a decision. The assignment of this category 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.

Criteria

Evaluation of available relevant information* indicates that, under site-specific conditions of exposure, exposures to site-specific contaminants in the past, present, or future are not likely to result in adverse impact to human health.

*Such as environmental and demographic data; health outcome data; exposure data; community health concerns information; toxicologic, medical, and epidemiologic data; monitoring and management plans.

ATSDR Actions

The following public health actions may be recommended for sites in this category:

• cease or further reduce exposure*
• community health/stress education
• health professional education
• community health investigation

*This conclusion category is based on information indicating that no human exposure is occurring or has occurred in the past to hazardous substances at levels of public health concern. Therefore, recommendations to reduce exposure are not needed to reduce risk, but may be considered prudent public health practice centered on prevention or may be deemed appropriate to minimize potential future impacts.

If additional data become available suggesting that human exposure to hazardous substances at levels of public health concern is occurring, or has occurred in the past, ATSDR will reevaluate the need for any follow-up actions or activities.

CATEGORY 5: NO PUBLIC HEALTH HAZARD

This category is used for sites that, because of the absence of exposure, do NOT pose a public health hazard.

Criteria

Sufficient evidence indicates that no human exposures to contaminated media have occurred, no exposures are currently occurring, and exposures are not likely to occur in the future.

ATSDR Actions

The following public health actions may be recommended for sites in this category:

• community health education
• no recommendation at this time