ANCHORAGE (AP) -- Further testing of wastewater from three cruise ships operating in southeast Alaska has found no evidence of heptachlor, a toxic pesticide banned in the United States in the 1980s.
Testing in September found very small amounts of the pesticide, used in some other countries to kill termites and other insects. Further testing of the samples done the following month found no evidence of the pesticide, said David Wetzel, laboratory manager for Analytica Environmental Laboratories' Juneau office.
''There aren't any detectable pesticide residue in these cruise ship samples,'' Wetzel said.
Princess Cruises spokesman Tom Dow said the results are good news.
''My main reaction is that I'm relieved that the test results showed this pesticide isn't present,'' he said.
The tests were paid for by the cruise ship industry with the understanding that the results would be provided to the state Department of Environmental Conservation and the Coast Guard.
After initial tests indicated the presence of heptachlor, DEC officials speculated that the pesticide may have been used on wooden crates that store fruits and vegetables grown overseas. The cruise ship industry wondered if the pesticide, used in some countries to eradicate bugs from cotton fields, could be leaching from sheets and towels.
Given the results of the new tests, Wetzel said another compound likely mimicked heptachlor in the initial testing. What that compound is, remains a mystery, he said.
''There is no way to say,'' Wetzel said.
The three wastewater samples were tested for over 125 pollutants, including most pesticides, using Environmental Protection Agency standards.
''This method is extremely responsive to certain types of compounds, such as organochlorine pesticides... Unfortunately, it also responds to many other compounds commonly found in household and other typical environments, and can give rise to ''false positives,'' Analytica's news release said.
Further testing involved concentrating the samples and passing them through a column to screen certain substances while allowing heptachlor through, Wetzel said.
Mike Conway, DEC's coordinator for the Alaska Cruise Ship Initiative, a task force of cruise ship industry representatives, state and federal regulators and representatives of the public, said DEC is reasonably comfortable that heptachlor is not in cruise ship wastewater.
Heptachlor now is being given a low priority, but won't be forgotten, he said.
''We should revisit it when we do any sampling in the future,'' Conway said.
Peninsula Clarion ©2014. All Rights Reserved.