Concerns regarding the persistence in the environment and toxicity to various flora and fauna of oil dispersants date back to their early use in the 1960s and 1970s. Both the degradation and the toxicity of dispersants depend on the chemicals chosen within the formulation. Compounds which interact too harshly with oil dispersants should be tested to ensure that they meet three criteria:
* They should be biodegradable.
* In the presence of oil, they must not be preferentially utilized as a carbon source.
* They must be nontoxic to indigenous bacteria.