Students are back in class at Honokaa schools, where some 1,000 people were evacuated Thursday after fumes from a mixture of pesticides sent more than two dozen people to area health centers.
None of the more than 20 students who were transported to North Hawaii Community Hospital required medical care. Students were examined in a decontamination tent and discharged in hospital gowns so their clothes could be decontaminated, said Wayne Higaki, emergency management coordinator and chief development officer for the hospital.
A Department of Agriculture inspector took swab samples at the schools and at the nearby home where the mixture of diazinon and Volck oil were sprayed on a hedge. The Department of Agriculture is also testing for the insecticide malathion, which was found at the residence, said Dean Yoshizu, environmental health specialist with the DOA Pesticides Branch.
“The inspector thought he smelled malathion so that’s one of the things we’re testing for,” said Yoshizu, who expected results by the end of next week.
Police are still investigating the incident and will follow up with Department of Agriculture on whether the substance sprayed was a banned pesticide, said Hawaii Police Capt. Andrew Burian.
Honokaa High and Intermediate and Honokaa Elementary schools were affected by the odor.
“There is no trace of the foul smell or dangerous fumes,” said West Hawaii Complex Area Superintendent Art Souza on Friday. “The fumes themselves were not dangerous in the sense that they could have caused neurological damage.”
Yoshizu confirmed that there was no lingering odor during an inspection of the site, located about 100 feet from the school buildings.
Forty students and 10 adults reported nausea, dizziness and respiratory problems following the early morning spraying. The Environmental Protection Agency banned the sale of diazinon in 2004 and implemented a buy-back as part of an effort to phase out the spray, formerly one of the most widely used pesticides in the United States under trade names including Spectracide and Basudin. Volck oil is a petroleum-based insecticide in common use.
Malathion is an organophosphate that works by affecting the nervous system, and has wide uses in agricultural and yard settings and has been used in public health mosquito control, according to the National Pesticide Information Center.
The diazinon ban was part of a larger effort by the EPA to get rid of a group of organophosphates that can affect the human nervous system, but the ban doesn’t apply to commercial and agricultural uses of the product.
“It is legal for consumers to use diazinon products, provided that they follow all label directions and precautions,” according to an EPA fact sheet. “Use of these products according to label directions does not pose an immediate hazard. However, consumers should know that EPA took this action to protect children and the environment.”
Because there was no recall of diazinon stocks, the product in many cases has sat around on consumers’ shelves for years. Yoshizu said consumers should carefully follow the labels on pesticide containers and properly dispose of unwanted and defunct sprays through a hazardous waste collection program.
Higaki said the NHCH erected an incident command center, added staff to the emergency room and called additional nurses in to work when it became clear that a large number of students were on the way to the Waimea hospital.
“It’s a wake-up call,” Higaki said. “We hold exercises each year for man-made and natural disasters. Although this was a real event, there were no major injuries or illnesses, and it created a process where we had a real exercise in addressing that kind of need.”