Most materials containing inert ingredients do not specify which list these ingredients are on. Organic production allows only EPA List 4 synthetic inerts in pesticides. Verification from the manufacturer that synthetic inert ingredients, contained in pesticides, are on List 4 is needed to demonstrate compliance. Often times manufacturers are unwilling to disclose the identity of inerts, but may be willing to confirm whether they are all on EPA List 4 or not. Approval by OMRI or an accredited certifier can also be used to demonstrate that the inerts are acceptable.