Around 15 small bags of a pest control substance containing Feratox was found along Waiotahe Beach last night.
Feratox is an encapsulated form of cyanide used for pest control and was found on the high tide line of the beach.
Bay of Plenty Regional Council said they were notified via the Pollution Hotline.
“Regional Council staff were on site last night and located a further two bags to what was reported,” Council said.
Four staff and an iwi representative were on site at first light to search the area between the Waiotahe River mouth and the entrance of Opotiki Harbour.
Additional staff are also searching from Bryan’s Beach to the west of the Waiotahe River and East of the Opotiki River mouth “to ensure a buffer zone is in place while recovery of the capsules takes place.”
Council said at this stage it's not know “how many capsules are on the beach and where they originated from” and advise people to stay away from the area.
Council advise anyone who see a capsule to stay away from it call their Pollution Hotline on 0800 884 883.
Regional Council is working the Environmental Protection Authority (EPA) and Worksafe regarding the safe recovery and disposal of the capsules, as the use of Feratox has licensing requirements for its use, handling and disposal.
“Regional Council appreciates the understanding and support of local residents and beach users while the clean-up is underway.”