University of Hawaii scientists said Friday that their water sampling data in neighborhoods on the Navy’s water system that show a number of detections of what could potentially be jet fuel should trigger concerns about the drinking water’s safety.

But the methodology employed by the UH researchers has been panned by the state Department of Health and Navy, which spent months doing extensive testing and analysis of the Navy’s water system after it was contaminated in November by jet fuel from the Navy’s nearby Red Hill fuel facility. The methodology, called fluorescence spectroscopy, is not certified by the U.S. Environmental Protection Agency, and DOH says it is prone to false positives. A top official at the Honolulu Board of Water Supply also said the method is very limited in what it can discern about the quality of drinking water.

During the DOH and Navy water testing, thousands of military families were displaced for months, living out of Waikiki hotel rooms. On March 18, DOH finally declared the water in all of the affected neighborhoods around Joint Base Pearl Harbor-Hickam safe to drink, making the newly released UH data, which shows possible fuel detections as late as May, all the more jarring.

DOH and the Navy have continued to sample the water using EPA-certified methods in accordance with a long-term monitoring plan and have said that there have been no signs of contamination. They say the water remains safe to drink.

The UH data, briefly made public Tuesday and covered by the media, caused a stir and prompted attorneys representing military families who were affected by 2021’s Red Hill water contamination to call on the Navy to begin evacuating families, saying that it confirmed the water remained contaminated.

UH posted the data on the university’s website Tuesday in anticipation of a news conference planned for later that day, which was canceled with little explanation. UH spokesman Dan Meisenzahl said that the information had been released prematurely and that university officials hoped to better explain what the data meant during Friday’s news conference, which he opened by apologizing for any anxiety that the “communications mistake” may have caused residents, particularly those affected by the Red Hill water crisis.

“We are not trying to create any kind of extra concern or panic. It is about providing knowledge,” said Meisenzahl.

On Thursday, Meisenzahl told the Honolulu Star- Advertiser that the data did not contradict DOH’s conclusions that the Navy’s water is safe to drink.

But that message got muddled as the UH researchers, who are part of a Red Hill task force at the university, began discussing what they think the data shows.

They stressed that the methodology is a screening tool, and rather than providing conclusive results, it should trigger follow-up testing to obtain EPA- certified results.

“I think it’s incumbent on people who have had a positive detect in their tap water to follow up and get further testing, and in the meantime I think it is probably prudent not to drink the water,” said Thomas Giambelluca, a geography professor and director of the UH Manoa Water Resources Research Center.

Craig Nelson, an associate research professor at UH Manoa Oceanography, said that a positive detection should not create alarm about a specific community. “But it is interesting, and that is why we put the data out there, because if five of your neighbors also have a positive detect, you will have to use your judgment of what to do there,” he said.

However, the public can’t tell whether the “detects” are their neighbors; they can only see whether one is in their neighborhood. UH’s Tap Water Screening Dashboard doesn’t provide exact street locations. Detections are coded by dots — gray meaning no detection, yellow meaning possible detection and red meaning positive detection.

The graphs show positive detections in the neighborhoods of Ford Island, Hickam, Iroquois Point, Ohana Navy Communities, Pearl City Peninsula and Red Hill Mauka. The samples were tested between December and May.

In addition to providing only the neighborhoods, the dashboard doesn’t make clear that the “positive” fuel detections are actually possible fuel detections.

Donn Viviani, a math and natural sciences instructor at Leeward Community College, said that in some cases the data could provide residents with assurances that their water is safe.

“In a way our results could actually allay people’s concerns, to some degree,” he said. “If there are 12 dots in your neighborhood and one or two are positive, that might give somebody a feeling that, OK, there is something going on, but it’s not fully in all of our water all the time.”

Initially, residents were collecting samples themselves and providing them to UH for testing. UH says that since February it has been using trained task force members to collect the samples, using a specific protocol that includes purging the faucet for 10 seconds to remove stagnant water from pipes, using specific, pre-cleaned glass vials and storing the samples in a refrigerator, among other best practices.

The UH testing was initiated after the Red Hill crisis made clear that Hawaii and Navy officials had no way of quickly testing water samples to see whether they were contaminated with fuel. The turnaround time is typically weeks. The UH method allows for low-cost, rapid screening of large numbers of samples, and results can be ready in a few days.

The researchers say the rapid testing method can allow environmental regulators to respond more quickly to a contamination crisis and take safeguards to protect residents’ health and the environment. It took days for DOH and the Navy to confirm that the Navy’s drinking water was indeed contaminated with fuel after residents began complaining that they were getting sick.

The UH researchers also made clear Friday that fluorescence spectroscopy cannot tell for sure whether what they are seeing is actually jet fuel, but that the detections resemble it. They couldn’t give a rate for false positives.

DOH said Friday that the fluorescence screening method used by UH is not specific for petroleum products and that it can detect other organic material, including material that commonly builds up inside of pipes — bacteria, algae or leaves —which can result in false positives.

Still, DOH said that it takes UH’s statements seriously and will do follow- up testing using methods certified by the EPA.

Giambelluca said that it’s possible that the group will expand its research and testing in the Red Hill area, as well as other areas of Oahu that are on the Honolulu Board of Water Supply’s system. However, the UH researchers said they hadn’t consulted BWS about their work.

Erwin Kawata, who oversees water quality for BWS, said Thursday during an interview with the Star- Advertiser that fluorescence spectroscopy is not a method they would use to test their water.

“Every analytical method needs to be thoroughly vetted. It needs to go through an extensive method detection study,” he said. “Certain techniques are best suited for certain applications. Fluorescence, in terms of monitoring for petroleum, is not really the best way to to do it. It is not the best technology to apply. It might be able to give you some very gross macro-indicators, but that’s probably the best it is ever going to give you. It is not going to give you anything quantitative or definitive.

“So really, the use of fluorescence spectroscopy by UH, or in this case using JP-5, we have certain reservations about that, for sure. It’s not a method that we would use.”