The Chemical Mixture Methodology using Health Code Numbers
The Chemical Mixture Methodology (CMM) provides recommended default emergency exposure guidelines for mixtures of chemicals. The CMM makes extensive use of Health Code Numbers (HCNs) to examine the additive impact that each chemical component in a chemical mixture may have on specific target organs. The CMM is a more realistic predictor of potential human health impacts than can be obtained using the (1) non-conservative method of separately analyzing the consequences of each chemical component or the (2) overly-conservative method of adding the exposures from each chemical together regardless of the human organ targeted by the chemical. The CMM is recommended by SCAPA for potential use in emergency planning hazards assessments (EPHAs), safety analyses, and in emergency response situations. To use the CMM, download the CMM workbook and carefully review the CMM user’s guide.
The latest version of the Chemical Mixture Methodology Workbook (Revision date: 11/20/07) is available for use. A User's Guide for the Chemical Mixture Methodology (Revision Date: 11/26/07) explains how to use this Excel workbook.
Additional information on the CMM and HCNs are provided in the CMM and HCN background information webpage.
The CMM Development Team
Rocky Petrocchi is the leader of the CMM development team. Dr's. Xiao-Ying Yu and Jayne-Anne Bond provide technical support. Donna Trott is the team’s graduate student intern and has developed Health Code Numbers (HCNs) for many hundreds of chemicals. Doug Craig is the original developer of the CMM and remains a creative force on the development team.
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Rocky Petrocchi |
Xiao-Ying Yu |
Jayne-Anne Bond |
The CMM team's activities are guided by the TEEL Advisory Group (TAG). The TAG is chaired by Tom Tuccinardi. Members include Jim Fairobent and Dave Freshwater from DOE/NA-41, Cliff Glantz (SCAPA Chair), Doug Craig, Rocky Petrocchi, Po-Yung Lu, Xiao-Ying Yu, Jayne-Anne Bond, and Richard Thomas.
Updates to the CMM Data Set
A major revision of the CMM data set will generally be released every year or two to accommodate the addition of new chemicals to the CMM data set and updates to health impact information.
Need HCN's for a New Chemical?
Please complete and submit this form: Word format | PDF format
If a chemical of interest is not in the PAC/TEEL or CMM data sets, please complete this form and e-mail it to the contacts listed at the bottom of the form. Requested chemicals will be added to a list that is prioritized for PAC/Teel and HCN development. Chemicals of critical importance can be given immediate attention.
Questioning an Existing HCN Value?
Please complete and submit this form: Word format | PDF format
If you have a problem with an existing HCN value (e.g., a HCN number is not given for a target organ you believe is impacted by the chemical), please document your concerns in this form and e-mail it to the contacts listed at the bottom of the form.
For Further Information...
For further inquiries about the CMM, please send an e-mail the PAC/TEEL Development Team. If you need to speak directly with a member of the team, your first point of contact should be either Rocky Pertrocchi or Xiao-Ying Yu.