Established in 1992

as ERT Associates, Tohn Environmental Strategies is an environmental and health policy consulting firm dedicated to providing clients the technical and strategic help they need to advance their goals. For fifteen years, Tohn Environmental Strategies has been led by founder and Principal Ellen Tohn, a nationally recognized expert in environmental health, healthy housing, green building, indoor air quality and lead poisoning prevention.


We pride ourselves on our responsiveness to client needs and long term client relationships. We help developers, architects, designers, and multi family housing owners/managers create and maintain green and healthy buildings. Federal and state agencies seek our assistance when developing and evaluating health, environmental and housing programs. Non profit organizations come to us for strategic assistance in designing initiatives, managing advocacy campaigns, and structuring innovative collaborations across public and private sectors.

Ellen R. Tohn (Principal)

Ms. Tohn is an environmental and health consultant with over 20 years of experience. She is the founder and principal of Tohn Environmental Strategies and a nationally recognized expert in housing based environmental health threats, healthy housing and indoor air quality, and lead poisoning prevention. Ms. Tohn also has extensive sector experience working on clean air, solid and hazardous waste, toxic substances, and comparative risk. Ms. Tohn works with housing developers, property owners, managers and architects to create green and healthy housing. She has assisted national/regional and local health advocates catalyze effective and lasting policy solutions; contributed to numerous Federal and state guidance documents; developed Federal and local healthy housing and lead training courses; and designed and managed environmental health research studies resulting in peer-reviewed publications and influencing Federal regulatory actions. She recently directed a project to develop Guidance for EPA’s Energy Star Indoor Air Quality Specifications and serves as an advisor on indoor air quality issues to the US Green Building Council’s LEED for Homes standards setting process and numerous other green building programs.

Frequent Partners

Tohn Environmental Strategies collaborates with a range of firms and organizations when our clients require a more comprehensive set of services. Our partners include firms providing engineering and architectural services, statistical analysis, data base design, building science and research, and public relations. Frequent partners include:


Camroden Associates, Inc.
Nationally recognized indoor air quality and building science experts.


Independence Energy Homes
Independence Energy Homes offers architectural design for homeowners and design & energy consulting for developers. We specialize in energy efficiency, zero energy, and green design for residential new construction projects.


The Asthma Regional Council of New England
Regional coalition dedicated to reducing the burden of asthma on children and families through collaborations of health, housing, education, and environmental organizations.


The National Center for Healthy Housing
The leading national non profit organization dedicated to creating healthy affordable housing through research, training, and program evaluation.

Selected Clients

Property Owners, Developers & Designers 
•  Enterprise Foundation
•  The Green Company
•  Urban Edge
•  Winn Residential
•  ZeroEnergy Design  

Federal Government 
•  U.S. Agency for Healthcare Research and Quality
•  U.S. Centers for Disease Control
•  U.S. Environmental Protection Agency
•  U.S. Department of Housing and Urban Development 


State & Local Government 
•  Maine Dept. of Environmental Protection
•  New Hampshire Dept. of Health & Dept. of Environmental Services
•  North Carolina Dept. of Environment and Natural Resources
•  Rhode Island Dept. of Environmental Management
•  Vermont Dept. of Environmental Conservation


•  Alliance for Healthy Homes

•  American Lung Association of Rhode Island
•  Asthma Regional Council of New England
•  Boston University School of Public Health
•  Conservation Services Group
•  Greater Boston Breathes Better
•  Greater Minnesota Housing Fund
•  National Center for Healthy Housing
•  Southern Rhode Island Health Education Center 


“We know we’re going to have an informative, motivational, and fun seminar whenever Ellen is scheduled to speak to health and housing issues for health and housing agency staff and housing developers. She delivers an energetic and dynamic presentation, and Ellen’s warm and engaging personality is perfect for communicating even the most technical content. We try to have her as part of our speaker roster whenever possible.”

Marian L. Heyman, MPH
Coordinator, Indoor Environment Quality Unit
Environmental & Occupational Health Assessment Program
Connecticut Department of Public Health

“Ellen`s energetic and dynamic presentation style, combined with her warm and engaging personality results in seminars that are informative, motivational, and fun. I like having her as part of our speaker roster whenever possible.”

Marian L. Heyman, Coordinator
Connecticut Department of Public Health

“We were committed to reducing the asthma rates among our residents, but did not have a plan. Tohn Environmental Strategies played a pivotal role helping our local task force define a strategic plan, attract resources, and develop our core materials. They helped us pull all the pieces together to create a pioneering model program where property owners, maintenance staff, and health professionals all commit to improve indoor air quality and health care services. We simply could not have achieved our goal without Ellen Tohn and her team.”

Jim Reed
Executive Director
Newport Rhode Island Housing Authority

“As Executive Director of a national nonprofit policy and advocacy organization, I benefited greatly from Tohn Environmental Strategies advice and assistance for more than 10 years. Ellens rare mix of strengths and skills give her strong command of technical issues, creativity to think outside the box, ability to find common ground with potential allies, foresight to anticipate opportunities, and a determination to find solutions that are practical. Ms. Tohn was worth her weight in gold as a strategic thinker, sounding board, and creative partner.”

Don Ryan
Founder and Former Executive Director
The Alliance for Healthy Homes

“Ellen’s technical understanding of housing and health issues has been instrumental in helping our organization develop healthy housing building guidelines and training as well as develop and evaluate programs to improve indoor air quality. The firm has been a long time strategic advisor helping us navigate key strategic decisions. Ms. Tohn is simply a delight to work with!”

Rebecca Morley
Executive Director
The National Center for Healthy Housing