About 30 students at St. Joseph School in Waipahu became ill yesterday after pesticide fumes spread through part of the campus, officials said.

Students reported symptoms including eye and throat irritation and headaches because of the fumes, which were first noticed about 1:30 p.m. No one required hospitalization.

Investigators believe the fumes were caused by a school employee using a common pesticide, Malathion, on the campus grounds.

"For some reason, the fumes were stronger than usual and spread into the classroom," Fire Department spokesman Terry Seelig said.

Fire Department and Emergency Medical Services personnel responded to the school and treated students at the scene until their parents were able to come, Seelig said.

City Emergency Services spokesman Bryan Cheplic said 29 students and two adults were treated at the scene. No one was acutely affected or directly contaminated by the pesticide, Seelig said.

Fire Department and rescue personnel arriving at the school at 94-651 Farrington Highway said school officials had already begun to put an emergency reaction plan into place, separating the students who were reporting symptoms and moving them into air-conditioned spaces.

"They did a good job of calming everyone down," he said.

About 400 students from pre-kindergarten to the sixth grade normally are on campus during the day, Seelig said.