Assessing Risks to Human Health
With the exception of certain workers, no harm is expected from use of indole-3-butyric acid. The active ingredient is not toxic to humans or other mammals. Furthermore, indole-3-butyric acid is effective at very low concentrations--often several orders of magnitude below 1%. It is applied at very low rates compared with most other pesticides. In animals, indole-3-butyric acid is rapidly broken down to a closely related, harmless chemical that occurs naturally in living organisms.
Eye irritation to certain workers is EPA' s only health concern for products containing indole-3-butyric acid. For products that may cause eye irritation, workers (such as mixers and applicators) are required to use protective eyewear, such as goggles, face shield, or safety glasses.
Assessing Risks to the Environment
No risks to the environment are expected from use of this active ingredient because 1) it does not harm animals or plants in the tiny amounts used, 2) it acts as a plant growth enhancer, 3) it does not persist in the environment, 4) it is closely related to naturally occurring substances.
