The state Department of Environmental Quality has released 2017 air quality monitoring data showing naphthalene levels emitted by AmeriTies West are almost half of what they’ve been previously, a spokesperson said.
As part of a voluntary odor-reducing effort, AmeriTies changed its creosote formula in December 2016 to cut the amount of naphthalene in half.
Naphthalene is an ingredient in the creosote formula that AmeriTies uses as a preservative to treat railroad ties, making them more weather- and insect-resistant. It has a distinct odor of mothballs.
DEQ, which did a round of testing in 2016 before the formula change, did more testing afterwards. It tested three areas, from mid-July to mid-September last year. The highest measured concentrations were found at the Wasco County Planning office, which is located just outside the boundaries of the 80-acre tie plant at the east end of The Dalles.
The average concentrations of naphthalene found at all three monitoring stations were above the benchmark for cancer risk, but below the acute exposure benchmark, and the benchmark for non-cancer health effects.
The cancer risk benchmark is .03 micrograms per cubic meter. The acute exposure level is 200 micrograms per cubic meter and the non-cancer risk level is 3.7 micrograms per cubic meter.
The findings from the air quality report showed naphthalene concentration levels between .002 and 2.48 micrograms per cubic meter.
That compares to 2016, when naphthalene concentration levels ranged from .006 to 5.78 micrograms per cubic meter.
In the 2017 testing, the average concentration of naphthalene per cubic meter was 1.16 at the Wasco County building, .3 at City Park and .04 at 10th and Cherry Heights.
The results showed that high temperature correlated with higher concentrations of naphthalene.
AmeriTies had less production in 2017 compared to 2016, but more treated products were stored in 2017, according to the DEQ.
John L. McGinley, president of AmeriTies West LLC, said of the air monitoring results, “AmeriTies is pleased to learn of the latest monitoring results showing decreased naphthalene levels in The Dalles. Our company has modified our operations, invested in new equipment and, in December 2016, switched to a new, low-naphthalene treatment formula. AmeriTies continues to conscientiously comply with all state and federal health and safety regulations.”
Naphthalene is found not only in the wood preservative used at AmeriTies, but is also found in cigarette smoke, car exhaust and smoke from forest fires, according to the National Pesticide Information Center.
Kristina Cronkright has said at earlier DEQ public meetings about naphthalene that she moved away because of it. She said that while the latest report focused on reduced levels of the chemical, “The fact of the matter is, the lifetime cancer benchmark is being exceeded, even as far west as Cherry Heights.”
The lifetime cancer benchmark is the level which, with constant exposure over an entire lifetime, represents enough long-term risk to cause one case of cancer per one million people.
Greg Svelund, a spokesman for DEQ, said the naphthalene is coming from the hundreds of thousands of ties in the yard that are off-gassing, or emitting vapors as they cure in the yard.
“The warmer it is, the more off-gassing,” he said.
Svelund said the DEQ is still doing on-going air quality monitoring that will go on for a year.
Meanwhile, another report by the Agency for Toxic Substances and Disease Registry is due in a few weeks, he said.
That report, called a health consultation, will look at the concentrations of naphthalene and determine if there’s any kind of health risk, and what those risks are.
“I think that’s going to answer some health questions that folks have,” Svelund said.
He added that the DEQ has “pretty much exhausted” all the options listed in a 2016 agreement made with AmeriTies to reduce odors.
“I think that’s good and bad,” Svelund said. “I think we have demonstrated a reduction and we’ve pursued all of the options that were identified in that agreement to reduce odors.
He said, “We demonstrated a reduction in emissions but how that translates to a reduction in odors is two different things. It’s complicated.”
“Frankly, there’s limited tools available to us at the state level to further reduce odors. That’s just a reality,” he said.
He said the DEQ still gets a steady stream of odor complaints about AmeriTies, even after it halved the level of naphthalene used in its formula.