Saturday, March 17, 2018
Massive pesticide testing confirms: Hawai`i Surface Waters "Meet State & Federal Water Quality Standards"
Ground zero has somehow slipped away. There is no evidence of widespread pesticide contamination in Hawai`i’s surface waters, according to a thorough federal study of water resources on two islands.
That confirms similar results in separate tests from 2014 and 2016.
It would seem that HAPA, SHAKA, the Center or Food Safety can fold up their tents and go home. Their work is done. If the claims of rampant agricultural pesticide misuse were ever true, they are not true now.
The U.S. Geological Survey conducted 7,200 water tests in 2016 and 2017—one of the broadest scientific investigations ever into allegations of pesticide misuse in the Hawaiian Islands. There were 12 surface water test sites on Kaua`i and 19 on O`ahu.
Here is the state Department of Agriculture public release on USGS testing of water samples at 31 sites on Oahu and Kaua`i, for 225 different pesticides.
“The sites included streams, ditches, canals, and a wetland– and were near or downstream of agricultural areas, developed areas, or both,” the study said. Here is the study itself.
The short version: The laboratory tests were able to detect pesticides, but all at levels below federally and state levels of concern.
Bizarrely, while the last decade of allegations of pesticide misuse have gained widespread publicity across the state, the proof that those claims were unfounded has slipped almost entirely under the radar.
The state’s news media allocated pages upon pages of newsprint and web content to pesticide contamination allegations, but almost nothing to the actual scientific proof that these claims were were overblown.
The Garden Island newspaper on Kaua`i, dismissed the study in a brief (9 paragraph) story. Honolulu-based media have had nothing to date.
The new USGS study is now being repeated on O`ahu and Kaua`i, and is also being expanded to Maui and Hawai`i counties.
“This multi-year surface water study goes a long way towards assuring the citizenry of Hawaii that pesticides are continuing to be used properly,” said Scott Enright, chair of the Hawaii State Department of Agriculture.
The surface water study is not an outlier. It confirms the conclusions of several previous studies.
It supports information by a groundwater study by an independent California laboratory for the Kaua`i Department of Water Supply in 2016, which found no pesticide levels of concern in groundwater from several Kaua`i agricultural sites. Here is the RaisingIslands coverage of that study.
That study confirms annual testing by the island’s Water Department of all its drinking water sources. Those tests can be seen here.
A statewide surface water testing effort in 2014 had results along the same lines. Here is Honolulu Civil Beat’s piece on that statewide program, which found that most pesticide concerns were in urban streams, and not in agricultural areas.
As noted above, the new USGS study did not fail to find pesticides, but where it found them they were at exceedingly low levels. Here are some of the notable findings, from the state Department of Agriculture release, including what is being done about those pesticides:
“Chlorpyrifos was detected in two Honouliuli stream samples collected during the same high-flow storm event. The highest concentration of 23.3 ng/l is below the state water quality standard of 83 ng/l and the strictest acute benchmark of 50 ng/l for the protection of freshwater invertebrates. HDOA is currently in the process of restricting the use of chlorpyrifos by reclassifying it to a restricted-use pesticide (RUP) which will allow its use by only state-certified applicators. The proposed restrictions will mirror what California has done and includes required buffer zone. These rules are anticipated to be finalized by this summer.
“Concentrations of flubendiamide in high-flow samples collected at two sites on Oahu exceeded the lowest Federal aquatic-life benchmark. Flubendiamide is an insecticide that the U.S. Environmental Protection Agency (EPA) is currently in the process of cancelling its use due to the risk to aquatic invertebrates and aquatic environments.
“Atrazine, an herbicide and established groundwater contaminant, and an RUP was detected in low-flow samples at three sites, at concentrations more than 100 times lower than the EPA maximum contaminant level for drinking water and the strictest aquatic life benchmarks. This represents a significant drop compared to the 75 percent detection rate in a 2013-14 study. The decline likely reflects the decrease in current atrazine applications and sales statewide after 2015, during the time that saw the closure of a large sugarcane plantation.
“Bromacil is an herbicide and established groundwater contaminant used almost exclusively on pineapple in Hawaii. Bromocil was detected in two areas, one of which is known to have grown pineapple.”
All but one of the samples identified at least one pesticide compound. A total of 61 different pesticides were identified across the two islands. The most commonly identified pesticide was Atrazine—either directly or from a compound that Atrazine degrades into.
Atrazine is a long-lived herbicide that was commonly used in the sugar industry, but is still used to control broadleaf weeds in agriculture today. It is the agricultural chemical most widely detected in water samples across the nation.
© Jan TenBruggencate 2018