Detection of carcinogens as mutagens in the Salmonella/microsome test: assay of 300 chemicals.

Introduction:
This text presents the results of a study conducted by Joyce McCann, Edmund Choi, Edith Yamaska, and Bruce N. ames, which aimed to detect carcinogens as mutagens using the Salmonella/microsome test. The study tested around 300 carcinogens and non-carcinogens of various chemical types for mutagenicity. The test uses bacteria with sensitive indicators for DNa damage and mammalian liver extracts for metabolic conversion of carcinogens to their active mutagenic forms.

Key Points:

* The study tested about 300 carcinogens and non-carcinogens, and found a high correlation between carcinogenicity and mutagenicity (90% of carcinogens were mutagenic in the test).
* The test uses bacteria with sensitive indicators for DNa damage and mammalian liver extracts for metabolic conversion of carcinogens to their active mutagenic forms.
* The test can detect a wide variety of carcinogens requiring metabolic activation.
* The system has been reviewed and the test method has been described in detail.
* The test has been used in a large number of carcinogens and non-carcinogens of many different classes, and the correlation between mutagenicity and carcinogenicity has been determined.
* The test has been used by several laboratories, including a large contribution from Japan, and is sponsored by the National Cancer Institute and the Environmental Protection agency.
* The study did not test any metal carcinogens, and did not find any mutagenic activity in 46 common biochemicals that are non-carcinogens or presumed non-carcinogens.

Main Message:
The study demonstrates the utility and limitations of the Salmonella/microsome test in detecting environmental carcinogens and mutagens. The test has been sufficiently developed and validated to be considered for widespread use as a screening technique for identifying dangerous chemicals. The study also highlights the strong correlation between carcinogenicity and mutagenicity, supporting the idea that rapid and inexpensive screening methods are needed as complements to expensive, long-term animal tests to pinpoint hazardous chemicals among the thousands to which humans are exposed.

McCann, J, E Choi, E Yamasaki, and B N ames. “Detection of Carcinogens as Mutagens in the Salmonella/Microsome Test: assay of 300 Chemicals.” Proceedings of the National academy of Sciences 72, no. 12 (December 1975): 5135–39. https://doi.org/10.1073/pnas.72.12.5135.