health assessment

Improving IRIS: Please Join the Conversation

By Kacee Deener

IRIS graphic identifier

Over the past few years, EPA has embraced a major new effort to enhance its Integrated Risk Information System (IRIS) Program to improve the scientific foundation of assessments, increase transparency, and improve productivity. IRIS is a human health assessment program that evaluates information on health effects that may result from exposure to environmental contaminants. Information from IRIS is used by EPA and others to support decisions to protect human health.

We think we’ve made terrific progress so far, and we were thrilled that the National Academies’ National Research Council (NRC) agrees. They spent the past two years reviewing IRIS, and in May 2014, they issued a report highlighting our progress and offering recommendations on keeping the progress moving forward (Assistant Administrator Lek Kadeli recently wrote about this on EPA Connect, the Agency’s leadership blog).

In their report, the NRC commended EPA for its substantive new approaches, continuing commitment to improving the process, and successes to date. They noted that the IRIS Program has moved forward steadily in planning for and implementing changes in each element of the assessment process. They also provided several recommendations which they said should be seen as building on the progress we’ve already made.

We are happy to announce that we are taking additional steps to improve the IRIS Program. In October, we will hold a public workshop to discuss specific recommendations from the NRC’s report, which fall under the three broad topics below. We invite you to provide early input by commenting on this blog post, which is the first in a new IRIS blog series geared toward generating online scientific discussion about issues relevant to the IRIS Program. We plan to use blog posts like this more in the future to get your input.

  • Topic 1 – Refining systematic review methodology, including methods to evaluate risk of bias. The NRC stated that EPA should continue to document and standardize its process for evaluating evidence and recommended EPA develop tools for assessing risk of bias in human, animal, and mechanistic studies that are used as primary data sources. The NRC noted the limitations of available approaches for use with observational (nonrandomized) studies, and advocated exploration of differences in applying methods for evaluating epidemiological studies to controlled experimental in vivo and in vitro studies. They noted that these approaches will depend on the complexity and extent of data on a chemical and the resources available to EPA, and that additional methodological work might be needed to develop empirically-supported evaluation criteria for animal or mechanistic studies.
  • Topic 2 – Advancing methodology to systematically evaluate and integrate evidence streams. The NRC stated that EPA should continue to improve its evidence-integration process incrementally, and to enhance its transparency. The committee provided several alternatives for organizing evidence of hazard potential and recommended that the IRIS Program should either continue with the guided-expert-judgment process for evaluating evidence, but make its application more transparent, or adopt a structured approach with rating recommendations. The committee also encouraged the IRIS Program to simultaneously expand its ability to perform quantitative modeling, specifically using Bayesian methods, to inform hazard identification.
  • Topic 3 – Combining quantitative results from multiple studies, presenting appropriate quantitative toxicity information, and advancing analyses and communication of uncertainty. The committee encouraged the IRIS Program to continue its shift towards the use of multiple studies for dose-response assessment, but with increased attention to judging the relative merits of mechanistic, animal and epidemiologic studies, with an ultimate goal of developing formal methods for combining studies and deriving toxicity values in a transparent and replicable manner. The NRC stated that it is critical to consider systematic approaches to synthesizing and integrating the derivation of a range of toxicity values in light of variability and uncertainty. Integral to this latter goal is the NRC recommendation to develop methods to systematically conduct uncertainty analyses and to appropriately communicate uncertainty to the users of IRIS assessments.

We’re interested in hearing your thoughts about the NRC recommendations above. For example, do you have ideas about how we should move forward to address the recommendations in these topic areas? Do you have scientific suggestions for the IRIS Program to consider related to these topics? Do you have suggestions for who we should ask to speak at the workshop? Please add your thoughts, ideas, and suggestions in the comments below and join the conversation!

About the Author: Kacee Deener is the Communications Director in EPA’s National Center for Environmental Assessment.  She joined EPA 13 years ago and has a Masters degree in Public Health.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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100 Days of EPA Science, and Beyond

By Kacee Deener

Numeral 100 with clouds and sky in backgroundEPA recently highlighted some of the Agency’s achievements during Gina McCarthy’s first 100 days as Administrator, noting that we have made significant strides towards improving the health of American families and protecting the environment across the country.

One of the seven highlighted examples is “Taking Action on Toxics and Chemical Safety” – which includes strengthening chemical assessments through changes to the Agency’s Integrated Risk Information System (IRIS) Program.  In a recent blog post, I described these changes and why they make sense for the IRIS Program, the Agency, and the American people.  But the IRIS Program hasn’t stopped there.  We’ve been moving forward implementing the changes.  Since August, we have:

  1. Released early materials for several chemical assessments.  These materials highlight our thought process for determining which studies are most important for the assessment, help make sure we didn’t miss any important research, and help identify potential scientific controversies early on.
  2. Scheduled the first IRIS public bimonthly meeting (Dec. 12-13).  At this meeting we will discuss the early materials for three chemicals (ETBE, tert-butanol, and RDX) and the draft assessments and peer review charges for two chemical assessments (ethylene oxide and benzo[a]pyrene).
  3. Held a public scientific workshop to discuss the IRIS assessment of hexavalent chromium.  An important component of determining the cancer causing potential of ingested hexavalent chromium is understanding the rates at which this metal is effectively detoxified in the gastrointestinal tract.  EPA convened an expert panel to discuss this issue in September; more than 200 stakeholders participated!
  4. Scheduled a scientific workshop on mouse lung tumors.  At this workshop, which will be held in early 2014, experts will discuss the available data from studies of mouse lung tumors following exposure to chemicals and discuss the relevance of these tumors in mice to assessing human cancer risk.
  5. Released final IRIS assessments for biphenyl, 1,4-dioxane (inhalation update), and methanol (noncancer). These final assessments provide information on the health effects of these chemicals and toxicity values that risk assessors can use (along with exposure and other information) to make decisions to protect public health.
  6. Announced a workshop on formaldehydeThis workshop, which will be held in spring 2014, will focus on several scientific issues pertinent to assessing the potential health effects of inhaled formaldehyde.  We’re taking input on speakers/panelists and topics for three theme areas – you can send us your suggestions here.

I think you’ll agree we’ve been making tremendous progress!  These activities illustrate our commitment to scientific integrity, public input, and transparency as we work together to produce the highest quality scientific assessments to inform decisions to protect public health.

About the Author: Kacee Deener is the Communications Director in EPA’s National Center for Environmental Assessment, home of the IRIS Program.  She joined EPA 12 years ago and has a Masters degree in Public Health.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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Writing Down IRIS

By Kacee Deener IRIS

As a scientist now working in science communications, I’m constantly surprised by the writing process.  You put something down on paper, revise it a few times, and then make tweaks here and there until you’re satisfied.  Then you look at it again later, and you make a few more changes.

Turns out lots of things in life are like that—including science programs.  In May 2009, EPA announced a new Integrated Risk Information System – or IRIS – assessment development process.

IRIS is an important program because it provides information on the health effects caused by exposure to chemicals in the environment.  People use IRIS, along with other science information, to inform decisions that protect public health across the U.S.

The new 2009 process was good for the IRIS Program.  But – as I’ve learned with writing – a few tweaks can make something even better.  Since 2009, we’ve learned a lot.  We’ve also received recommendations from the National Research Council (NRC) about improving IRIS assessments and about planning and scoping and stakeholder engagement in risk assessment.  So we’re making some common sense changes that will help us produce more high quality assessments in a timely and transparent manner.

In a nutshell, here’s what we are doing

  • Before beginning an assessment, we will meet with EPA’s regulatory programs – the folks who make decisions that help protect public health – to make sure we understand the big picture of why they need an assessment.
  • We will then hold a public meeting to discuss the plan for the assessment (so we better understand who needs it and why) and gather input about some technical aspects of developing the assessment (for example, are we concerned about people being exposed by breathing the chemical, ingesting it, or both?).
  • Next we will release a literature search for the chemical, evidence tables that summarize the critical scientific studies, and exposure-response figures that graphically depict the responses at different levels of exposure for each study in the evidence table. These materials highlight our thought process for determining which studies are most important for the assessment, help make sure we didn’t miss any important research, and help identify any potential scientific controversies early on.
  • We’re also using “stopping rules” so IRIS assessments are not delayed by ongoing research or scientific debate after certain points of the process have passed.
  • Finally, we’ve strengthened our practices for peer review and conflict of interest.

And this isn’t a complete list – you can read about all of the enhancements on our website.

These changes to IRIS are practical, common-sense improvements that emphasize scientific rigor and transparency.  They will also be good for our stakeholders, so like a well written story, it’s a win-win for everyone involved.

Like a committed science writer, we’ll always be revising whenever improvements are needed, but take a minute to check out the latest edition.  I think you’ll like the improvements.

About the Author: Kacee Deener is the Communications Director in EPA’s National Center for Environmental Assessment, home of the IRIS Program.  She joined EPA 12 years ago and has a Masters degree in Public Health.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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HERO: Easier Way to Retrieve Information

By Pawlos Girmay

I recently had an opportunity to speak with Gerry Gurevich, the technical lead for EPA’s Health and Environmental Research Online—or HERO—database, which serves as a central location for the scientific information EPA researchers use to develop environmental and health assessments. Gerry explained some of the benefits of the HERO database and the changes that will occur over the coming months.

For starters, HERO has greatly enhanced transparency by providing links to the references and abstracts of  the scientific literature used in two important types of Agency assessments:  (1) Integrated Risk Information System (IRIS) assessments, which evaluate information on the potential health effects that may result from exposure to environmental contaminants, and (2) Integrated Science Assessments (ISAs), reports that summarize the science related to the health and ecological effects caused by the six criteria air pollutants for which EPA develops National Ambient Air Quality Standards.

With approximately 725,000 references, there is an abundance of information. If you need a scientific reference from an ISA or IRIS assessment, HERO will have it!

While HERO is already a terrific resource, EPA is still committed to making changes to improve the database. New versions of HERO are being pushed out monthly to improve performance. EPA will continue to provide updates as needed to make HERO a beneficial tool for anyone seeking scientific information about EPA’s assessment work.

Obviously, HERO could not function without the hard work and dedication of the staff that have made the database what it is today. Joining Gerry Gurevich, who has been working with HERO for the past four years, is “TeamHERO” – a group of librarians and data specialists.

During my time in the EPA’s National Center for Environmental Assessment, I found HERO to be an extremely valuable tool to search for scientific information. As part of the Open Government Directive to conduct business with transparency, participation, and collaboration, HERO helps the public participate in EPA’s work by providing information about the data behind health assessments that inform decisions to protect public health.

With many new advances in technology taking place, I am sure HERO will continue to expand and enhance stakeholder’s experiences.  You can explore it yourself here: Health and Environmental Research Online.

About the Author: Pawlos Girmay is a student intern in EPA’s National Center for Environmental Assessment. He received his undergraduate degree from Howard University and his Masters of Science in Health Communications degree from Boston University.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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Testing… Testing 1, 2, 3

By Janice Lee        

Arsenic element from periodic tableSo here we are preparing for the upcoming Public Stakeholder Workshop on the Integrated Risk Information System (IRIS) Program’s new health assessment of Inorganic Arsenic (January 8-9, 2013).  The goal of the public workshop is to provide an opportunity for stakeholders to share their views about the assessment.  

An IRIS assessment is important to organizations that make decisions about protecting public health because it provides information about a chemical’s hazard and the relationship between the dose of the chemical and the magnitude of its biological response or health effect.  

We’re interested in hearing from the public about what types of studies exist about inorganic arsenic and what is currently known about the chemical. We’re also interested in hearing why various organizations need a health assessment of inorganic arsenic.  For example, what sort of questions do they have to answer or what decisions do they have to make about the chemical?

The knowledge we gather from this important part of the process will help us better understand what should be included in the final assessment in order to meet the needs of the American public. 

You can participate in the workshop in person or remotely by webinar. The webinar option is great since many people who are interested in attending can’t come in person. Today we did a dry run to try out the webinar system and everything worked just fine. Now that we’re all set, I’m eager to see how many people join us using this technology.

As a graduate student, my doctoral work was on arsenic chemistry and health effects. One of the projects I worked on evaluated arsenic removal at a water treatment facility in Holly, MI. When I graduated, I thought I was done with arsenic. I just had to finish my manuscript and thought I would probably never work on arsenic again. Well, that was 10 years ago and here I am, the co-chemical manager for the inorganic arsenic assessment! 

I’m excited to be working on arsenic again, and in a different capacity this time around. Instead of doing research, I’m applying the research that has already been done to inform the development of an assessment that will be used as part of the science to inform future public health decisions about inorganic arsenic.

For more information on the workshop, check out the website: http://www.epa.gov/iris/publicmeeting/arsenic.htm

Please join us. We’re looking forward to hearing from you next week!

About the author:  Janice Lee is a health scientist in EPA’s IRIS Program. She has been with EPA for the past seven years and has a Ph.D. in Environmental Health Sciences.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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Your Voice Matters to EPA’s IRIS Program

By Kacee Deener

Last month, I attended an internal EPA meeting to discuss plans for developing an Integrated Risk Information System (IRIS) assessment for inorganic arsenic. The purpose of the meeting was to talk with EPA’s regulatory programs about the scope of the assessment.

An IRIS assessment is only part of the information EPA uses to make decisions—it provides information about the chemical’s hazard and the relationship between the dose of the chemical and the magnitude of the biological response or health effect. I know from my days as a public health student that IRIS is really important to environmental and public health practitioners in EPA and across the country—they use the database every day to help inform decisions to protect public health. So it’s important that we understand what questions people may have to answer about a chemical before beginning an assessment. This helps us appreciate the big picture of the work we’re doing; it also helps us focus the assessment so it’s most useful to the people who use IRIS. For example:

  • Are there upcoming rules where inorganic arsenic will be a risk driver?
  • Are EPA regions facing decisions about cleaning up sites contaminated with inorganic arsenic?
  • What types of toxicity values does the Agency and other stakeholders need to do its work?

These are just some of the questions that were asked during this internal meeting.

This type of meeting will become more common in the IRIS Program. However, we won’t just meet internally about these questions. We want to expand the conversation about IRIS with all stakeholders, including state and local health agencies, industry, environmental and public health organizations, the general public, and any individual or group that has an impact on, an interest in, or could be affected by an IRIS assessment.

We understand that IRIS assessments inform the decisions that EPA makes every day to protect public health and the environment. We know these decisions can have a big impact on human health, the environment, and the economy. Because of this, stakeholder engagement is critical to promote transparency and understand the views and input of those impacted by IRIS.

On November 13, we will hold a public stakeholder meeting about IRIS, and we are inviting anyone who’s interested to participate. But this is only the beginning—we plan to have an ongoing dialogue with stakeholders about the IRIS Program and specific IRIS assessments. We are interested in hearing what you think, so come join us on November 13. We would love to hear from you!

About the author: Kacee Deener is the Communications Director in EPA’s National Center for Environmental Assessment, home of the IRIS Program. She joined EPA 12 years ago and has a Masters degree in Public Health.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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Teaching Risk Assessment in Cairo, Egypt

by Abdel Kadry, John Vandenberg, and Ila Cote

My colleagues and I were delighted to respond to an invitation from Professor Dr. Osama El-Tawil, the Chairman of Toxicology & Forensic Medicine Department, Faculty of Veterinary Medicine, Cairo University, to provide an international training course on risk assessment. We arrived in Cairo on May 16, 2012.

Over the next three days, we offered comprehensive training on current, state-of-the-art risk assessment practices as used and implemented by EPA and various international organizations. The course is titled “Risk Assessment as a Critical Tool for Everyday Challenges.”

More than 300 men and women from throughout the Middle East attended the training. The course offered hands on training in the primary areas of risk assessment (i.e., hazard identification, dose-response assessment, exposure assessment, risk characterization). Additionally, we covered risk communication, because outreach to the public and other stakeholders is essential to the successful implementation of risk assessment.

Throughout the course, there were discussions of real environmental and public health problems experienced in the country. Students had the opportunity to apply skills learned in class to these problems in several small breakout sessions. In addition to learning about risk assessment, the participants formed new friendships and extended their professional networks.

The course also attracted a large number of newspapers and TV stations. This training represents a culmination of knowledge sharing among science experts in the field of risk assessment. (For more information about the course go to: EPA Risk Assessment Class at Cairo University.)

It was such great opportunity to meet the leadership team of Cairo University, especially: Professor Dr. Prof Hossam Kamel, President of Cairo University; Professor Dr. Azz Eldin Abostat, Vice President of Students Affairs, Cairo University and Professor of Agriculture Science; Professor Dr. Gamal El-Din Essmat, Vice President for higher studies, Cairo University; Professor Dr. Heba Nassar, Vice President for Environmental and Society Services, Cairo University; and Professor Dr. Fathy Farouk, the Dean of  the Faculty of Veterinary Medicine, Cairo University.

On Sunday, we were invited by the Dean of the Veterinary School to tour Cairo University (home to 250,000 students), meet the faculty and discuss their research. We visited the famous library of Cairo University, the veterinary clinic, microbiology laboratories, and the latest incineration facility in Cairo University, which is charged with sanitary disposal of infectious biologic materials.

About the Authors:  John Vandenberg, Division Director; Ila Cote, Senior Science Advisor; and Abdel Kadry, Senior Advisor for Scientific Organizational Development and International Activities in EPA’s National Center for Environmental Assessment.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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Sharing EPA Knowledge 7,000 Miles Away

By Abdel Kadry and Ila Cote

With an invitation from the U.S. embassy in Riyadh, two of my colleagues and I traveled to Saudi Arabia last month to provide risk assessment training to Saudi and other scientists in Riyadh and to participate in a scientific dialogue with Saudi government officials and others on the Global Methane Initiative.

Dr. John Vandenberg

For three days, we represented the United States in the Saudi International Environmental Technology Conference 2012, which was organized under the patronage of King Abdullah Bin Abdulaziz, the King of the Saudi Arabia. The conference was at King Abdulaziz City for Science and Technology (KACST), an independent scientific organization that encompasses both the Saudi Arabian National Science Agency and its National Laboratories.

KACST plays a pivotal role in the development of the National Science, Technology and Innovation policy and leads 62 government agencies and over 190 national programs and related projects for the development of the Kingdom’s strategic technologies. KACST also funds more than 400 independent research projects annually and acts as the Kingdom’s patent office.

The conference we attended hosted a large gathering of researchers, investors, decision makers and those interested in developing environmental technology. One goal was to facilitate achieving the priorities of the Saudi National Strategy for Environmental Technology.

The conference was organized around three main tracks:

  1. Air pollution and air quality.
  2. Waste & soil contamination & remediation.
  3. Climate change impacts and solutions.

My colleague, John Vandenberg, provided the plenary talk, and our team of three EPA scientists offered risk assessment training for the entire third day of the three day conference. Our training focused on the principles and application of risk assessment.

Dr. Ila Coate

We structured the training to include lectures combined with case studies, with a lot of time allotted to discussing the case studies.

We had excellent attendance and the participants were very engaged in the course material.  We also had the pleasure of meeting Saudi officials such as His Highness Dr. Turki AL Saud, the KACST vice president, who expressed considerable appreciation for the important international role that EPA plays in protecting human health and the environment. The team was also very proud that Dr. Ila Cote, who, as the only female speaker in the conference, provided much inspiration for the Saudi female scientists.

About the Authors:

Abdel Kadry is the Senior Advisor for Scientific Organizational Development and International Activities in EPA’s National Center for Environmental Assessment (NCEA).  Abdel has organized a series of international risk assessment training activities for NCEA, with a focus on developing countries.  Ila Cote, Senior Science Advisor in NCEA, and John Vandenberg, Director of the Research Triangle Park Division of NCEA, accompanied Abdel to Saudi Arabia to provide risk assessment training last month.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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Protecting Human Health: That Explains It!

By Elizabeth Erwin

Child plays with water.

EPA's IRIS Program provides health effects information to help protect public health and the environment.

This past December, I had the opportunity to attend the annual Society for Risk Analysis (SRA) meeting in Charleston, SC. One of my responsibilities was to cover a symposium on EPA’s Integrated Risk Information System (IRIS) chaired by Becki Clark, Acting Director of my EPA office, the National Center for Environmental Assessment (NCEA).

Over the past year, I have become very familiar with IRIS, as a large part of my job is to communicate to the public, other federal agencies, and stakeholders what IRIS is, what it isn’t, and what it does to protect human health and the environment.

When I mention IRIS to friends and family, I’m often met with quizzical expressions. After several failed attempts at an explanation that included chemical names like “hexabromocyclododecane” and other scientific mouthfuls, I began giving them the bottom line: while IRIS assessments are not regulations or by themselves full risk assessments, the information they contain is an important basis for decisions that protect the health of all Americans.

Obviously, each of us has at some point taken a drink of tap water, inhaled deeply while enjoying an afternoon outside, or tracked soil into our homes. We perform these and dozens of other mundane daily activities without giving a second thought to potential harmful consequences, thanks in large part to EPA’s actions, many of which are based on IRIS human health assessments of more than 550 chemical substances.

Earlier this year, EPA finalized the long-awaited non-cancer assessment for dioxin, a major milestone for the Agency. Dioxins are toxic chemicals that exist in the environment naturally and can be released in greater quantities through forest fires, backyard burning of trash, certain industrial activities, and residue from past commercial burning of waste.

This final IRIS assessment is the latest effort in a successful, coordinated strategy by the Federal government that has reduced known and measurable air emissions of dioxins in the United States by about 90 percent since 1987.

Risk assessors, health professionals, and state, local, and international governments can now use these latest findings to guide future efforts to identify any residual sources of dioxin and protect public health.

Achievements such as this are what make me proud to be associated with EPA’s IRIS Program, especially when I get that oh-so-common question, “So, what do you do?” Attending the IRIS presentation reminded me that to answer that question, all I have to say is simply, “I help support the science that protects human health” – because that’s exactly what the IRIS Program does.

About the Author:  Elizabeth Erwin is a member of EPA’s science communication team where she helps make IRIS and other EPA science programs and assessments available and accessible.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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EPA’s Path Forward for the Integrated Risk Information System Program

By Becki Clark

EPA has a lot to be proud of.  Today, we all enjoy cleaner air, water and land because of actions taken by EPA over the past 40 years.  One thing that I’m personally proud of is EPA’s Integrated Risk Information System Program, or IRIS, and the changes we are making in the Program.

IRIS assessments are not regulations or full risk assessments, but the information they contain about the potential human health effects from long-term exposure to chemicals provides an important part of the foundation for decisions made to protect the health of all Americans.

In April 2011, the National Research Council (NRC) gave EPA some recommendations for improving the development of IRIS assessments, and we are working hard to implement them.  At first, we focused on editing and streamlining documents.  We are now in the next phase of our work, and we will soon release two draft assessments that represent a major advancement for the Program in implementing the recommendations.

For anyone who is familiar with IRIS assessments, the changes we’ve made will be immediately apparent.  Assessments will look different because we are using a new document structure that is more streamlined, concise and clear. However, the changes are far from just cosmetic.  In fact, the IRIS Program is fundamentally changing the way we develop assessments – from the way we select and evaluate the quality of studies, weigh the overall evidence of each effect, and select studies for deriving toxicity values.

EPA recently announced that the National Academy of Sciences would conduct a review of the IRIS assessment development process and the changes being made in the Program.  They will also convene a workshop on weight of evidence and recommend approaches to EPA.  The NAS’ feedback will help guide us as we continue to improve IRIS assessments.  Additionally, the results of the weight of evidence workshop will help us develop or adopt a formal weight of evidence framework for health effects other than cancer.

I’m proud to be a part of IRIS, because it plays a significant role in protecting the health of our country’s citizens.  I believe that a strong, scientifically rigorous IRIS Program is of critical importance. That’s why I am committed to making the changes recommended by the NRC.  I am excited about these changes, and I think you will be pleased when you see the results.  My staff and I will continue to pursue excellence in the IRIS Program, using the most up-to-date science in support of EPA’s mission to protect the health of the American public.

About the Author:  Becki Clark is the Acting Director of EPA’s National Center for Environmental Assessment.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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