Toxic air contaminants: scientific community


Please note: If you would like to request a Spanish interpretation, please email cdphe_apcd_outreach@state.co.us and include “Air Toxics Scientific Panel Interpretation Request” as the subject line.

Tenga en cuenta: Si desea solicitar interpretación al español, envíe un mensaje por correo electrónico a cdphe_apcd_outreach@state.co.us e indique “Air Toxics Scientific Panel Interpretation Request” como asunto de su mensaje.

Scientific community technical working group



The Colorado Department of Public Health and Environment convened a scientific community technical working group in January 2024. The working group is focused on toxic air contaminants. This working group aligns with requirements in a 2022 state law: Public Protections from Toxic Air Contaminants (HB22-1244).

The working group and associated outreach provides opportunities for scientific experts to participate. The goal is to develop collaborative, science-based solutions that prioritize transparency and inclusivity.

Air Pollution Control Division staff seek scientific community input prior to developing proposed rules on air toxics to strengthen the proposals. 



On June 2, 2022, Public Protections from Toxic Air Contaminants (HB22-1244) was signed into law. This law requires rulemaking actions by the Air Quality Control Commission to:

  1. Identify up to five priority toxics air contaminants. 
  2. Adopt health-based standards for each priority toxic air contaminant. 

The law requires that the health-based standards must be in numerical concentrations in the ambient air that establish chronic exposure limits that protect the public from adverse health effects. The standards must include an ample margin of safety.

The law requires input from the scientific community on these two topics before the division proposes draft rules to the Air Quality Control Commission. 


Purpose of technical working group

The group’s members will work collaboratively to recommend priority toxics air contaminants and associated health-based standards. 


Objectives/responsibilities of technical working group

Participate in meetings and the Air Quality Control Commission public hearing.

Review and evaluate the proposed data sources and prioritization framework used to narrow the list of 477 toxic air contaminants.

Provide feedback on the initial set of no more than five priority toxics air contaminants.

Review and evaluate the numeric concentrations established for chronic exposure limits for priority toxics air contaminants that are protective of human health and include ample margin of safety. 


Working group members

The technical working members provide a diverse mix of expertise in air toxics exposure effects (cancer and non-cancer). The group also includes individuals with expertise in ambient air concentrations and how those relate to assessing human health exposures.

The working group includes representatives from:

  • Academia.
  • Environmentally-focused non-governmental organizations.
  • Local governments.
  • The regulated community.

Technical working group members include:

Sheryl Magzamen headshot

Sheryl Magzamen, PhD (Academia) - Is an Associate Professor at Colorado State University in the Department of Environmental and Radiological Health Sciences as well as the Epidemiology Concentration Lead at the Colorado School of Public Health. Dr. Magzamen specializes in examining how social and environmental factors intersect in chronic diseases, particularly respiratory health. Her work involves creating advanced exposure assessment models for childhood and occupational respiratory diseases in community and agricultural settings. Her current research employs novel methods to analyze environmental pollutant mixtures in community-based studies.

Tami McMullin headshot

Tami McMullin, PhD (Industry) - As a Senior Toxicologist at CTEH, Dr. McMullin brings over 13 years of experience in a range of disciplines, including public health, regulatory toxicology, and environmental risk assessment. Her expertise lies in consulting toxicology with a specialization in the areas of industrial and agricultural chemicals, personal care products, and medical devices. Her work also includes health risk assessments related to chemical exposures and addressing public health concerns in the oil and gas sector.

Annareli Morales headshot

Annareli Morales, PhD (Government) - As an Atmospheric Scientist and Environmental Health Specialist at the Weld County Department of Public Health and Environment, Dr. Morales conducts comprehensive air quality policy analyses, addressing criteria pollutants, hazardous air pollutants, air toxins, and greenhouse gasses. Her areas of expertise include mountain meteorology and cloud microphysics. She also excels in bilingual science communication and education, making complex scientific concepts accessible to diverse audiences.

Meagan Weisner headshot

Meagan Weisner, PhD (Non Profit) - As a Senior Health Scientist for the Global Clean Air program for the Environmental Defense Fund, Dr. Weisner is dedicated to researching the health effects associated with living near unconventional oil and gas sites and areas with air toxic exposure. Her past research efforts have focused on socio-economic disparities related to metal exposure and the impact of climate change on minority communities. She has a strong foundation in GIS, epidemiology, and environmental justice, contributing significantly to these fields.

Michelle Mabson headshot

Michelle Mabson, MPH (Non Profit) - As a Staff Scientist at Earthjustice's Healthy Communities Program, Ms. Mabson has a robust professional history that includes working at the EPA's Office of Children’s Health Protection and significant research in environmental health. She serves as a member of the NAACP’s Climate and Environmental Justice Committee which works to reduce harmful emissions and advocate for increased air monitoring in Black and Brown communities. Ms. Mabson is also pursuing her DrPH at John Hopkins Bloomberg School of Public Health through the Health Initiatives Fellowship.

Alison Bauer headshot

Alison Bauer, PhD (Academia) - An accomplished Environmental and Occupational Toxicologist and Cancer Biologist, Dr. Bauer serves as an Associate Professor at the Colorado School of Public Health, University of Colorado Anschutz Medical Campus. She is interested in how environmental and occupational exposures to toxicants contribute to human lung diseases, particularly asthma, chronic obstructive pulmonary disease, and cancer. The focus of her research is on determining the molecular mechanisms driving these diseases, and use these mechanistic insights to predict disease incidence, provide data for improved policies and risk assessment, and develop preventive and interventive strategies for improving outcomes in human health.

Uni Blake headshot

Uni Blake, DrPH (Industry) - As the Director for Environmental Health and Community Engagement at the American Petroleum Institute, Dr. Blake brings a wealth of knowledge from her 15 years in Toxicology prior to joining API. She is a seasoned professional in environmental health and sustainability, with extensive experience in addressing environmental exposures in the energy sector. Her responsibilities include leading strategic policy analyses and pioneering sustainable initiatives, emphasizing energy justice and active stakeholder engagement.

Brendan Lawlor headshot

Brendan Lawlor, BS (Government) - Serving as the Senior Air Quality Specialist for the Love My Air Program with the Denver Department of Public Health and Environment (DDPHE). Brendan oversees the air quality sensor network that monitors and reports the levels of air pollution in different areas of Denver. He combines his experience in environmental health and data analysis to find effective ways to improve the air quality and raise awareness among the public. He is motivated by his passion for tackling environmental issues and improving health outcomes.


Technical working group meeting schedule

You can listen to each technical working group meeting live. The division will provide links below to access each meeting. Meeting materials will be published below after each meeting. 

The working group will convene from Jan. 2024 and through Feb. 2025. Specific meeting dates will be published below once finalized.

  • January 31st 2024. at 10 a.m.
  • April 24th 2024. at 10 a.m.
  • June 26th 2024. at 1 p.m.
    • Agenda: Discussion on the revised prioritization framework and resulting options for priority TAC.
    • Link to register for the June 26 webinar.
  • September 2024. 
  • November 2024.
  • December 2024 or January 2025.

Public meeting opportunities

The Air Pollution Control Division is providing opportunities for public meetings on these priority air toxics and associated regulatory requirements. Registration is required. The next meetings are:

During the meetings, staff from the Air Pollution Control Division will present to the public about the upcoming priority air toxics and health-based standard rulemakings including an overview of how these air toxics were prioritized.

Air Quality Control Commission rulemaking and informational hearing schedules


Priority toxic air contaminants

  • Request for rulemaking: Oct. 16 –18, 2024.
    • Topic: The division will request that the Air Quality Control Commission set a hearing to consider establishing a new Regulation Number 30 to identify up to five priority air toxic contaminants, as required by HB22-1244.

Health-based standards

  • Informational hearing: February 2025.
    • Topic: The Air Quality Control Commission will hold a public hearing to receive feedback from the scientific community participating in the technical working group.
  • Request for rulemaking: May 15 - 16, 2025.
    • Topic: The division will request that the Air Quality Control Commission set a hearing to consider revisions to Regulation Number 30. The revisions would address the health-based standards for the adopted priority air toxic contaminants, as required by HB22-1244.

Contact us


Email: cdphe_apcd_airtoxics@state.co.us

Use subject line: "Air Toxics Scientific Panel"

Future opportunities


The scope of the initial 2024-2025 scientific community technical working group is prioritizing and establishing an initial set of health-based standards.  The division anticipates future opportunities to evaluate:

  • Whether to incorporate acute exposure limits into the health-based standards. 
  • Input on more priority toxics air contaminants beyond those selected by April 2025.

The division will publish next steps and future public participation opportunities on this website.