# Welcome! . . . to theApril 2014 IRIS Bimonthly Public Science Discussion

December 20132 

## Today**’s Attendance Is More Diverse Than Before** 3 

## About IRIS IRIS assessments critically review the publicly available scientific studies on chemicals found in the environment to  Identify adverse health effects  Characterize exposure - response relationships HAZARD IDENTIFICA

TION Wh ich effects are credibly associated with the agent? DOSE - RESPONSE ASSESSMENT Characterize exposure response relationships Account for high -to - low-dose, animal -to- human, route -to route, and other differences EXPOSURE ASSESSMENT How do people come in contact with the agent? How much are they exposed to? RISK CHARACTERIZA

TION Integrate HAZARD, DOSE - RESPONSE, and EXPOSURE RISK MANAGEMENT Develop, analyze, compare options Select appropriate response LEGAL POLITICAL SOCIAL ECONOMIC TECHNICAL4



## IRIS Means Sy**stematic Review** 
Identify Pertinent Studies Evaluate Study Methods and Quality Evaluate W eight of Evidence for Each Effect Select Studies for Deriving Toxicity V

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## IRIS Means Multi **- level**  **Comment and Peer Review**
Identify Pertinent Studies Evaluate Study Methods and Quality Evaluate W eight of Evidence for Each Effect Select Studies for Deriving Toxicity V

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## IRIS Means Public Engagement

Public Discussion on Literature Search, Evidence Ta bles, Key Issues Public Discussion – EP A may revise draft assessment and charge in response to public comments Public Discussion on Problem Formulation Identify Pertinent Studies Evaluate Study Methods and Quality Evaluate W eight of Evidence for Each Effect Select Studies for Deriving Toxicity V

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## • General comments docket ( NEW!)
• Assessment- specific dockets
• Public science discussions during steps 1 and 4
• Public science workshops on specific topics Broadly attended meetings are useful for discussing science issues where there are multiple points of view
• Ad - hoc meetings with external stakeholders **There Are Now M**  **ultiple Way** **s to Engage w**  **ith IRIS** 8 

## Purpose: **to discuss key s**  **cience issues** What are key science issues? . . . They may pertain to  study methods or quality  approaches to reconciling positive and negative results  mode - of

- action hypotheses  alternative interpretations of the evidence  scientific considerations to address in the upcoming draft assessment

**Public Science Discussion**9 

## For each assessment . . .  Introduction by EPA assessment managers  For each science issue . . .

– Opening remarks by registered discussants

– Continued discussion by all meeting attendees  Open Forum on the assessment General Open Forum at the end of the meeting **Agenda for Today ’s**  **Public Science Discussion**10 Scoping • Direct hazards and stressors • Sources • Environmental exposure pathways • Individual intake pathways • At- risk populations • Direct adverse health outcomes Problem formulation • Hazard - identification methods • Stressor- characterization methods • Computational methods • Uncertainty- characterization methods • Intake and internal - dose models • Dose - response models and methods • Health - outcome measurements methods 

## Scoping and Problem Formulation: **Advice from the NRC**

Source: NRC 2009, Science and Decisions , boxes 3 - 1, 3 -211 Studies in laboratory animals • Species and sex • Dose, duration, route of exposure • Health effects considered • Relevance to human health effects of concern Studies in humans • Study population selection, potential for selection bias • Study population characteristics, generalizability • Exposure assessment, potential for information bias • Outcome identification, potential for bias • Appropriateness of analytic methods • Potential for confounding • Precision of effect estimates • Availability of exposure metrics 

### 1. Literature search to identify pertinent studies 2. Evidence tables to summarize study methods and results 3. Evaluate study methods and quality



## Identify **ing and Selecting Studies: Advice from the NRC** 

Source: NRC 201 1, Formaldehyde , pp 158 - 15912 

## 1. Literature search – summarized by PRISMA diagram 2. Evidence tables – summarize study methods and results 3. Evaluation of study methods and quality  Start with all pertinent, publicly available studies  Exclude studies based on problem formulation (beginning with Cr6, just released)  Exclude studies with fundamental flaws  Focus on studies with most robust methods (approaches can be discussed today) **Identify ing and Selecting Studies:**  **Current Thinking in IRIS**13 

## April releases  Literature search, evidence tables for Hexavalent Chromium (animal studies)  Literature search, evidence tables for Inorganic Arsenic  These will be discussed at the June 25 -27 meeting 

## June releases  Additional literature - search/evidence -table materials  Problem formulation materials  These will be discussed at the Sept 3 -4 meeting



## Future Public Science Discussions14 

## The Enhanced IRIS **Improved science**  - S ystematic review

- Toxicity values for all credible health hazards

- Strengthened peer review **Increased transparency**  - Clear, concise, systematic assessments

- Opportunities for public engagement **Increased productivity**  Wem ust make the Enhanced IRIS work by

completing more assessments in less time **IRIS will continue to evolve as we receive public**  **input and peer review advice –**  **Thank you!**