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Early Life Stage (ELS) Test

By Environmental Health Program
A gloved hand holds a small bird egg resting on a yellow sponge while a needle is placed through the shell.
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Detailed Description

Early Life Stage (ELS) tests are used as an alternative to traditional whole-animal testing methods for evaluating toxicity of chemicals. ELS for birds involve injection into the air cell of fertile eggs early in development and artificial incubation for several days at which point tissues are sampled for analysis. This biologically realistic alternative to currently available cell-based in vitro testing methods, allows the study of metabolic and multi-organ effects of the exposure.

Sources/Usage

Public Domain.