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CHARRED: Computerized Heterocyclic Amines Resource for Research in Epidemiology of Disease

Assorted red meats on a grill, with flames come up through the grate.

CHARRED is a software application to estimate intake of the mutagenic compounds in cooked meats.

Diets containing substantial amounts of red meat may increase the risk of various types of cancer. The association with red meat intake may be due to a combination of factors, such as content of fat, protein, and iron, and/or meat preparation (e.g. cooking or preserving methods). Experimental studies have shown that meats cooked at high temperatures contain heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs), which are mutagenic and carcinogenic in animals. To estimate intake of these meat-cooking mutagens, a detailed meat cooking module within a Food Frequency Questionnaire in conjunction with a mutagen database was developed.

Request Software

CHARRED Version 1.7 was released October 27, 2006. A revision history describing changes made for this release is provided in the CHARRED software Read-me page.

Access the Heme Iron Database

Macro SAS code for use with the heme iron database - This macro code can be pasted into a SAS program or included with an "include" statement and then called from the SAS program in order to generate the three variables below from food frequency data that corresponds to meats in the database file:

  • heme_iron = 'heme iron from meat (bhnrc) (mcg/day)'
  • rheme_iron = 'heme iron from red meat (bhnrc) (mcg/day)'
  • wheme_iron = 'heme iron from white meat (bhnrc) (mcg/day)'

SAS code for calculating nitrate and nitrite values for processed meats - This file contains SAS code for calculating nitrate and nitrite values based on grams of certain processed meats. There are two sets of calculations that were done for the AARP study, one based on previously published values and the other based on a database of measured levels in processed meats purchased in 2004.

Contact Us

If you have problems accessing CHARRED, please send an e-mail to