Other ingredients are not named on product labels for EPA-registered pesticides. That is because their identity is considered "confidential business information." Until 1997, other ingredients were always called "inert" ingredients, in contrast to "active ingredients." Both terms are found on product labels today.
While many of the chemicals that are used as other ingredients are not known to pose health or environmental risks, some of them can be toxic. In some cases, the other ingredients can pose greater risks than the active ingredient itself. Although the other ingredients are not required on the label, the signal word on the label indicates the toxicity of the formulated product (active and other ingredients combined).
If you have questions about this, or any pesticide-related topic, please call NPIC at 1-800-858-7378 (8:00am - 12:00pm PST), or email us at firstname.lastname@example.org.