Developing Documents

The PHA process can result in several types of written documents, depending on the site-specific circumstances and community needs. These documents include a public health assessment (PHA), a health consultation (HC), a letter health consultation (LHC), an exposure investigation-health consultation (EI-HC), a health advisory (HA), or a technical assist (TA). The documents have different audiences, preparation times, and requirements (refer to the Typical Information for Your Documents table below).

Typical Information for Your Documents

The main body of the document should fully address pertinent issues. Use appendices as appropriate to provide more detailed technical discussions and tables, figures, and maps whenever possible to make it easier to understand written text. Of utmost importance is to clearly reference all information sources. The primary document sections are briefly outlined below and all laid out in ATSDR’s document Outline [PDF – 217 KB] [DOC – 39 KB]. Health assessors need to refer to the document Outline [PDF – 217 KB] [DOC – 39 KB] for instructions on compiling and summarizing the different information collected throughout the PHA process and incorporating it into your documents.

Summary

The summary provides a brief introduction of the site, describes why ATSDR evaluated the site and what ATSDR did at the site, and presents conclusions, the basis for each conclusion, and next steps. The summary is the most frequently read section of the document. It needs to use plain language that is as simple, clear, and concise as possible. Be sure to use bottom line statements that provide the basis for the conclusions and highlight key evidence that supports the findings.

The table below shows the information mapping framework. Each conclusion should be listed separately and followed by its Basis for Conclusion and Next Steps. Health assessors have the option to list all of the Next Steps as one section after stating all the conclusions with their respective basis for the conclusions. If this option is chosen, be clear which step relates to which conclusion.

Background

This section includes two subsections.

• The Statement of Issue and Purpose does the following:
  • Describes ATSDR’s involvement at the site, why ATSDR is writing the report (e.g., the site is on the NPL, it was requested by EPA, or an exposure investigation to fill an exposure data gap), and what the site issues are
  • Poses the questions that will be addressed and indicates what the document will and will not discuss
  • Includes how contamination was discovered and the affected media (e.g., soil, water)
  • Excludes any information not directly relevant to the issues discussed in the main body of the document (you can place this information in an appendix if you judge it important to the reader)
• The Site Description and Timeline does the following:
  • Discusses the site location, land use (past, current, and future [if known], site geology/hydrogeology (if warranted), site visit, as well as include site maps. You learned about collecting this type of information in the Getting Familiar with the Site section.
  • Describes how the contamination was released to the environment and background information pertinent to the reader’s understanding of the site
  • Mentions conditions that could increase or decrease exposure such as ground cover, use of unregulated private wells, and high winds
  • Uses a timeline of site activities table, such as the example below to point out important activities related to the site. These can be activities related to contamination, cleanup, exposure, community meetings, and ATSDR involvement.
  • Ensures the information highlights details tied to your conceptual site model such as when contamination was released, contamination was identified, sample collection occurred, cleanup took place, and actions identified, stopped, or reduced exposure.
  • Includes only the key entries that are vital to understanding the activities that took place at your site. Consider date ranges to capture multiple similar events.

Example Timeline of Site Activities

Community Description and Concerns

This overall heading includes three subsections:

• The Community Demographics section includes the location of the potentially exposed populations and available demographic information pertinent to this evaluation (e.g., subsistence use of natural resources, potential increased risk factors, age groups, sex, and race/ethnicity).
• The Health Equity Considerations section (optional until guidance is developed), describes social vulnerability as reflected in the CDC/ATSDR Environmental Justice Index (EJI), and other environmental and social burdens in the community.
• The Community Concerns section introduces the community concerns that have been documented, as discussed in the Engaging the Community section. In this section, you will:
  • Talk about the efforts and steps taken to determine the health concerns, such as how you gathered the community’s concerns.
  • Include a brief overview of the health concerns voiced by the site community and if needed, include and reference a later section in the document that goes into more detail to specifically address and respond to individual health concerns (see Addressing Community Concerns section).
  • Mention that ATSDR has special considerations for child health issues and describe any children’s health considerations applicable to the site population and exposure.

Sampling Data (for Non-EI PHAs/HCs)

For non-EI PHAs and non-EI HCs, you will include the Sampling Data section. This section will do the following:

• Discuss the data sources for the sampling data you used to evaluate exposures and talk about the data representativeness (e.g., why the data are representative of exposures) and quality (e.g., are of high quality).
• Discuss data gaps as needed.
• May examine estimated contaminant concentrations in measured sampling data or modeled data, as noted in the Selecting Sampling Data section.

It can be challenging to summarize your evaluation of a site’s data, especially for sites with large volumes of data available. Be sure to do the following:

• Consider the information needs of the audience.
• Describe the sampling data for each medium examined, providing an overview of only the data you evaluated that were relevant to the exposure pathways.
• Communicate the information that would be most important to the readers without overwhelming them with unnecessary details — do not list every data point for every contaminant in every medium.
• Provide additional details in appendices of your document, if appropriate.

Methods and Sampling Data (for EI-HCs specific section)

If you are writing an EI-HC, you will include a Methods and Sampling Data section. In this section, you will have these three subsections:

• A Recruitment subsection that describes how participants were selected for the investigation (properties for an air investigation, human subjects for a biomonitoring EI).
• A Data Collection subsection that goes into detail about how and what types of data ATSDR collected throughout the program.
• A Laboratory and Data Analysis subsection that speaks to the laboratory methods to measure the contaminants and how the data were analyzed

Scientific Evaluations

As outlined in this e-manual, there are four scientific evaluations in the PHA process:

• Exposure Pathway Analysis,
• Screening Analysis,
• EPCs and Exposure Calculations, and
• In-Depth Toxicological Effects Analysis.

You will refer readers to these main PHAGM sections, as well as to the Explanation of ATSDR’s PHA Process Evaluation [PDF – 292 KB] [DOC – 50 KB], for more details on each of these evaluations rather than putting a lot of information about the process in your documents. This section summarizes scientific evaluations based on media-specific (e.g., household water, soil or sediment, outdoor or indoor air) exposures examined at your site, as shown in ATSDR’s document outline [PDF – 217 KB] [DOC – 39 KB].

For the Exposure Pathway Analysis subsection, you will do the following:

• Highlight the most important exposure pathway evaluation information to clearly describe how and to what extent people are believed to come in contact with site contaminants and what populations you have evaluated.
• Summarize your information in an Exposure Pathways table, as shown in the Exposure Pathways section.
• Provide information for each media-specific (e.g., household water, soil or sediment, outdoor or indoor air) exposure examined at your site.

In the Screening Analysis subsection, you will follow these steps:

• Include a table with the site contaminants that met or exceeded CVs and/or ATSDR screening levels, or that screened in because of a community concern. All of these contaminants will require further evaluation. At some sites, however, no contaminants will be identified as needing further evaluation, and you will need to explain why.
• State all assumptions that you used in your evaluation to select the contaminant concentrations, and to choose ATSDR CVs and non-ATSDR screening levels.
• Include a full list of contaminants in your screening analysis in an appendix if you choose (optional).

In the EPCs and Exposure Calculations subsection, you will do the following:

• Include a table showing the contaminants examined in the EPCs and Exposure Calculations evaluation (with their EPCs, doses/adjusted air concentrations, HQs, and CRs).
• Summarize the identified potential contaminants of concern needing further evaluation based on being above HQs and/or CRs.
• Show all contaminants included in this evaluation within this section of the main body of the document (ATSDR’s preferred method). However, you do have the option of showing only those contaminants identified as needing further evaluation in this section and putting a table with all evaluated contaminants in an appendix. At some sites, however, no contaminants will be identified as needing further evaluation, and you will need to explain why.
• State all assumptions that you used in your evaluation.

In the Health Evaluations subsection, you will do the following:

• Explain how site-specific exposure doses and adjusted air concentrations (and exposure conditions) compared with levels shown to cause harm in relevant scientific studies.
• Describe how the integration of pertinent site-specific data leads you to your overall decisions about whether site-specific conditions are likely to result in harmful health effects.
• State any assumptions used in your estimates (e.g., ingestion rates, exposure duration).
• Tie in exposure condition information that might provide additional perspective (e.g., how exposure levels compare to background and the likelihood of exposures).
• Identify the overall availability of pertinent health effects data for the contaminants and pathways of concern.
• Be sure your discussion supports and helps justify the conclusions.
• Highlight any strengths and weaknesses of contributing evidence that support your public health conclusions.
• State those instances when, because of weak or missing exposure or health effects data, an answer is not possible.
• Present only the decision point information for the highest doses and concentrations that form the reason for your conclusions. For instance, present the exposure groups with the highest level of exposures that drive the conclusions.
• Include information that will help the reader understand the public health conclusions, being sure to focus on the possible health concerns of the potentially exposed populations.
• Summarize information for particular groups on or near the site who, based on your review of contaminant-specific information, might be especially sensitive to toxic effects and were identified as suspected high-risk groups.
• Be as explicit as possible about why exposure levels are or are not expected to be a potential problem.
• Highlight any factors identified during your scientific evaluations that might make a particular exposure more or less likely. For example, explain why the presence of a particular metal in soil is not expected to be bioavailable and therefore unlikely to cause harm. On the other hand, explain why long-term exposures to detected levels of polychlorinated biphenyls (PCBs) in fish, for example, might under site-specific conditions, warrant more concern.
• Give perspective when using qualifying terms such as “low” or “high” to provide a comparison.
• Put additional information in an appendix.
• Decide if you will perform and summarize a mixtures evaluation (optional), as outlined in the Multiple Chemical Exposures section.

Evaluation of Health Outcome Data (HOD)

Include this section in your document if there are available HOD that you evaluated using ATSDR’s HOD criteria framework, as outlined in the Health Outcome Data (HOD) section. If conducted, you will do the following:

• Present a brief description of the requirement to consider health outcome (mortality and morbidity) data and the reasons why a health outcome data analysis was conducted.
• Have a concise description of the methodology used and the results of the analysis.
• Present a discussion of the inherent limitations in some types of Health Outcome Data review.

Addressing Community Concerns

Include this section if there are specific health concerns to address from community members, as noted in the Engaging the Community section. If added, you will do the following:

• Organize the concerns in an easy-to-read manner. For instance, presenting the concerns in a question-and-answer format is often most appropriate, as is organizing similar concerns together and using general categories to consolidate concerns by heading (e.g., health effects, personal and community safety, sampling).
• Be sure to follow the principles of effective communication described in Engaging the Community, which include presenting the information with clarity, accuracy, respect, and sensitivity.
• Protect privacy by not naming persons who expressed concerns, although you can name community groups that have raised concerns.

Summary of Limitations and Uncertainties

Summarize the major limitations from throughout the PHA process at the site that could affect your conclusions and recommended next steps. For example, limited data collected at the point of exposure, statistical limitations, limitations of scientific studies, and indoor air variability.

Conclusions

In this section, briefly present the conclusions (see Example Conclusions). You will do the following:

• List your conclusions in order of public health priority or importance if you have reached more than one conclusion.
• Assign a hazard conclusion category to the site, time period (e.g., past, current, or future), or exposure pathway, as appropriate. Conclusion categories are required in PHAs, HCs, LHCs, and HAs; when appropriate, they are included in EI-HCs. Be sure to clearly describe the basis for any selected conclusion category. Your conclusions will include the contaminant and pathway, length of exposure, and specific place (location of hazard). The conclusions should answer the following questions:
  • Who is the exposed population?
  • How did exposure occur (e.g., doing what activity)?
  • When and where did exposure occur?
  • What contaminants and physical hazards were people exposed to?
  • Will people be harmed from exposures?
  • What symptoms or health endpoints are associated with potential exposures?

• Use plain language to describe the essential messages of the document and make the conclusions clear and concise. Be sure that your information and explanatory text can be understood by general audiences.
• Include in the basis for the conclusions whether or not the levels are harmful and present evidence about what is known and not known to support the conclusions. When applicable, in your basis for conclusions, include the following types of information related to site-specific exposures:
  • Potential health effects that could occur from short-term and/or long-term exposures
  • Agency cancer classifications (e.g., EPA) for contaminants and whether cancer is known to occur in people exposed to those contaminants
  • Health effects that would likely go away after exposure stops
  • Important exposure factors, such as how often and for how long people would need to be exposed to have the listed health effects
  • Who could be more sensitive to potential health effects from exposure (e.g., children, elderly, people with high blood pressure)
  • Risk factors that could increase the susceptibility for health effects from exposures (e.g., smoking, taking certain medications, drinking alcohol)
  • Other activities or common sources that could also contribute to exposures (e.g., certain jobs, using particular cleaning products)

• Support each conclusion with a brief but adequate discussion of available data and information, without reiterating large portions of previous sections.
• Present a definitive statement (see Definitive Statement Example) about the health threat, if any, posed by a site, and highlight key issues.
• Present evidence about what is known and not known regarding the likelihood of harmful health effects under site-specific conditions.
• Make sure your health decision is supported by a clear story and follows other important writing guidance.
• Check that your conclusion statements are fully consistent with information presented in the Summary section and do not introduce new information (though, you will not use information mapping for this section). (See more conclusion examples in this Summary of Conclusion Categories table.)

Recommendations and Public Health Action Plan

This overall heading includes two subsections.

In the Recommendations part of this section, use the findings and conclusions to determine which of the following apply to your site:

• Describe recommended next steps needed to stop, prevent, or reduce exposures (see Examples of Recommendations) based on the conclusions reached about the site. Generally, it is most effective to organize them as a list and to begin each recommended next step with an action word (e.g., provide, monitor, restrict, obtain, inform).
• Be specific about data and information that need to be collected to help ATSDR make a health conclusion.
  • Ideally, communication among ATSDR and parties responsible for implementing the recommended next steps will have been ongoing throughout the PHA process.
  • Remember, ATSDR uses specific language about reducing and eliminating exposures when making recommendations, but always does so without suggestions related to risk management actions and decisions. For example, ATSDR will state a desired end goal (e.g., hook up homes with contaminated groundwater to the municipal drinking water supply), but does not specify how or what actions a responsible entity needs to take to meet that goal.
  • Such communication will help identify actions needed to implement the recommendations.
  • If applicable, include general recommendations for community members, such as to wash fruits and vegetables before eating them, or talk with their doctors if they have concerns.

• Be sure your recommended next steps are active, concise, parallel, and consistent with the Summary and Conclusions. You might have conclusions that do not result in recommended next steps, but you cannot have a recommended next step without a conclusion.
• State the urgency with which or the time frame in which the recommended next step needs to be addressed — if it is important.

• • This measure of urgency will indicate the gravity of the conclusion and establish priorities for responding to the recommendation.
  • Recommended next steps that do not have a completion time frame might be interpreted as a low priority
• State, if appropriate, that people do not need to take any action steps.
• Include action steps that ATSDR will do or did do to stop, prevent, or reduce exposures (include time frames, if needed).

In the Public Health Action Plan part of this section, you will do the following:

• Delineate completed, ongoing, and/or planned actions (see Examples of Recommendations) designed to mitigate or prevent harmful human health effects resulting from exposure to hazardous contaminants that might be associated with a particular site.
  • Parallel the actions with the recommendations.
  • State actions already taken to eliminate or prevent public health hazards.
  • Explain the specific plan in place to further investigate or eliminate remaining public health concerns, as detailed below.
• Indicate the entity (federal, state, local, or tribal agency; community or private party) that has agreed to or should have the responsibility of applying the recommendation.
• Include past public health efforts and activities in the site community for sites at which ATSDR has been previously involved.

Who Prepared the Document

This section will list the authors, site team, and others who contributed to the report.

References

This section will list the sources cited in the document.

Appendices

In your PHAs and HCs, and other documents, if desired, include as an appendix ATSDR’s standard one-page summary that describes the PHA process [PDF – 107 KB] [DOC – 26 KB]. In addition, the Appendices can include the following as appropriate and as needed:

• More details of your evaluation, and supplemental materials for any parts of the scientific evaluations, such as Screening Analysis, EPCs and Exposure Calculations, and In-Depth Toxicological Effects Analysis, and PHAST output tables. The purpose is to only provide essential information related to your evaluation and conclusions — you do not need to include step-by-step details of all your work.
• Other information needed to support your message, such as maps, models, and educational materials.
• Public comments and an explanation of how you addressed them in your document.

Information Mapping

Use information mapping to help narrow down the key messages you should share with your audience regarding your site-specific conclusions. You will have numbered conclusions (e.g., Conclusion 1, Conclusion 2), and present the basis for the conclusion and recommended next steps for each. See this table that presents an information mapping example. You can also refer to more information related to message mapping in ATSDR’s Message Mapping Template, Worksheet, and Checklist.

Follow these tips when framing your conclusions using information mapping:

• Organize conclusions from most hazardous to least hazardous, if appropriate (or use a different order if more suitable for your site conclusions).
• Be sure conclusions are pathway-driven but you can mention individual chemicals people are exposed to in each pathway.
• Reserve the 1) Summary and 2) Conclusions and Recommendations sections of your document for public health conclusions. During the PHA process, you will make conclusions about many things (e.g., sampling locations, data quality) that might provide supporting evidence for a public health conclusion but should not appear as a separate numbered conclusion in these sections.
• Determine conclusions that you can combine based on the same media, population, exposure scenario, or issue.
• Narrow your messages to three conclusions whenever possible; include no more than five.

Information Mapping Example

Accessibility

Health assessors producing materials for the public must meet the requirements in Section 508 of the Rehabilitation Act (29 U.S.C. 794d), also referred to as “Section 508” standards. This federal law requires agencies to provide equal access to electronic information and data to persons with disabilities as provided to persons who do not have disabilities, unless an undue burden would be imposed on the agency. Email any questions about 508 requirements to the CDC Section 508 Help Desk at 508helpdesk@cdc.gov.