Despite the city’s commitment to lower its use of pesticides, Seattle continues to apply thousands of gallons of pesticides to its parks and golf courses each year. And some parks the city branded “pesticide-free” have been treated with pesticides as recently as this spring.

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Almost 20 years ago, the city of Seattle — under pressure from environmental groups and children’s advocates — vowed to reduce the amount of pesticides sprayed on public lands.

Promising to phase out the most hazardous products, the city developed strategies and guidelines that prioritized eco-friendly methods of removing and preventing weeds. The measures showed early signs of success, with a 30 percent reduction in overall pesticide use over three years.

But the lofty plan of a phaseout soon faltered.

Pesticides the city considers among the most hazardous are still a regular part of its anti-weed arsenal, according to a city database obtained by The Seattle Times. Seattle Parks and Recreation sprayed more than 76,000 gallons of products containing those chemicals between 2012 and 2016, mostly to keep Seattle’s four golf courses well-groomed. That’s up from about 64,000 gallons in the five years prior.

And some parks that the city has branded as “pesticide-free” have been treated with pesticides as recently as this spring.

Meanwhile, new research has emerged showing that pesticides commonly sprayed at developed parks and playgrounds across the city may be more dangerous than initially thought. Glyphosate, the active ingredient in the popular product Roundup, was flagged as a possible human carcinogen by an international agency in 2015.

Despite policies that encourage the city to consider the developing science, Seattle has done little to use that new research to alter its spraying habits.

In 2016, Parks and Recreation conducted 732 pesticide treatments in parks that were either developed or in active restoration. More than 60 percent of these applications included glyphosate.

A Parks and Recreation official acknowledged that the agency’s pesticide-reduction efforts have not been up to its standards.

“It’s true, we need to get our act back together with this stuff,” said Barbara DeCaro, a senior environmental analyst in the department and the coordinator of Seattle’s integrated pest-management team. “Our committee wants to take another look and make sure the program ends up back on the radar for everybody.”

Slow to update

In 1999, Seattle contracted with the Washington Toxics Coalition — a nonprofit that advocates for the use of safer products, chemicals and practices — to help evaluate and target pesticides for elimination and reduction.

Philip Dickey, then a staff scientist for the coalition, created a tiered system based on a series of assessments from both federal and international regulatory agencies. The city focused on eliminating or phasing out products in the top two tiers.

The most harmful pesticides are in Tier 1, and include those determined to be likely carcinogens, endocrine disrupters or a hazard to birds, fish or bees.

A Tier 1 rating, Dickey said in an interview, means “the agency needs to look harder at why it’s using the chemical, and perhaps needs to think about limiting it or finding alternatives. It’s about putting it on a front burner and making it a top priority.”

Tier 2 pesticides are considered to be “of moderate concern.” Among those are Monsanto’s popular series of Roundup products, most of which include glyphosate.

Glyphosate was labeled “probably carcinogenic” after undergoing a hazard assessment by the World Health Organization’s International Agency for Research on Cancer [IARC] in 2015. Relying primarily on earlier studies involving mice, the IARC linked glyphosate to potential increased risk of Non-Hodgkin lymphoma, a cancer that develops in blood cells.

The finding should have triggered a process that would bump it to Tier 1, ultimately leading the city to reduce or discontinue the chemical’s use.

Yet records show Parks and Recreation has continued to use Roundup and label it a Tier 2 product. According to the database maintained by the department, the use of mixes containing glyphosate actually increased from about 570 gallons in 2015 to almost 1,500 gallons in 2016 — the highest level in the past nine years.

The IARC’s decision has prompted actions elsewhere — California is adding glyphosate this month to the state’s list of known carcinogenic chemicals — but also has been received skeptically by others in the scientific community. The federal Environmental Protection Agency and the European Chemical Agency have since said that available evidence does not point to glyphosate as a carcinogen.

Despite the city’s protocols, DeCaro, of the parks department, said she was hesitant to react to the IARC decision given that disagreement.

“I don’t know it’s good science to take one study and say we know this is true,” she said, pointing out that many anti-Monsanto scientists were quick to embrace the IARC ruling. “I want to make sure it’s not about [the] company and is truly about the science.”

Seattle’s Interdepartmental Team on Integrated Pest Management (IPM) — the group charged with implementing more environmentally sensitive strategies that prioritize pest control, rather than eradication — looked at the IARC report in 2015 but decided to wait for the EPA’s review to make a decision, DeCaro said.

But Dickey, who developed Seattle’s policies and retired from the Washington Toxics Coalition (now called Toxic Free Future) in 2008, had a different take. He said reviews of chemicals are not annual, so the most recent result ought to be given appropriate weight.

“When something like the IARC changes its mind, you should take into account the fact that it’s the current finding,” he said. “Think of it as a shelf-life thing — evaluations don’t happen at once.”

Another suite of products the city has continued to use, but to a lesser degree, is Tier 2 herbicides like Garlon 4, Element 4 and Surflan AS. Their active ingredient, oryzalin, has since 2008 been listed as a carcinogen by the California EPA, another one of the four agencies whose findings should trigger a reevaluation in Seattle.

But products that already have been assigned a tier are rarely reevaluated by the IPM team, DeCaro said. In response to a request for the most recently updated tier table, the Parks Department provided a document dated March 2009.

“None of us have really gone back through the entire list for a long time,” DeCaro said. “We are planning to do that, in the next couple years. It costs money for us to have that done by a third party.”

Pesticide-free parks?

Around the time the city got serious about phasing out Tier 1 chemicals, it also rolled out a new initiative: pesticide-free parks. There are now 22 scattered throughout the city.

But, The Times found, the label does not mean the parks are actually pesticide free.

In recent years, city data show, seven of those “pesticide-free” parks were treated with pesticides, including five sprayed with Roundup. They include Benefit Playground in southeast Seattle; Fairmount Playfield in West Seattle; and Regrade Park, a downtown off-leash area for dogs.

The city’s IPM team will occasionally allow an exception. That was the case over a period of three days in February 2016, when “pesticide-free” Lake Union Park’s shrub beds were treated with 28 gallons of a solution containing Surflan and Roundup, according to city data. That was one of three exceptions granted between 2007 and 2016, though only two were used.

When read the list of pesticide-free parks that had been sprayed in the past 10 years, DeCaro misidentified three of the five parks as not pesticide-free.

“That’s probably why [the parks were sprayed], nobody called me to ask,” DeCaro said. “As things roll over, sometimes people don’t know. Most should have ‘pesticide-free park’ on their sign, though.”

“I’m glad you spotted those,” she said to a Seattle Times reporter. “I usually don’t have time.”

Parks isn’t the only department that uses Roundup and other pesticides on city lands. Other land managers include the city’s transportation department and Seattle City Light.

In the past five years, Seattle Center has sprayed an average of 130 gallons per year of herbicides on its shrub beds, tree pits and hardscape, according to city data. In April and May 2017, the Center sprayed 36 gallons of diluted mixtures containing RangerPro or Roundup Pro to combat weeds around the International Fountain, the sidewalks adjacent to the Neototems Children’s Garden and the trees surrounding the Seattle Children’s Theatre, among others.

People gather around the International Fountain at Seattle Center, which treats its hardscapes and other areas with an average of 130 gallons of solutions containing pesticides each year. (Steve Ringman/The Seattle Times)
People gather around the International Fountain at Seattle Center, which treats its hardscapes and other areas with an average of 130 gallons of solutions containing pesticides each year. (Steve Ringman/The Seattle Times)

What San Francisco does

Since retiring from the toxics coalition about 10 years ago, Dickey has continued to work with San Francisco, which has adopted many of the same basic procedures and protocols he recommended for Seattle.

While initially based on Dickey’s protocol, San Francisco’s guidelines for evaluating pesticides were updated in 2013, according to Chris Geiger, a manager of the Integrated Pest Management Program in the city Department of the Environment. And each year, San Francisco conducts a review of its pesticide classification list and publishes an updated version.

Its 2017 Reduced Risk Pesticide List, updated March 21, gives use limitations and alternative chemicals. Roundup Custom and Roundup ProMax, whose active ingredients are glyphosate, are both listed as Most Hazardous (Tier I).

“We take IARC decisions seriously,” Geiger said. “It’s hard-wired into our screening system for pesticides. As soon as that determination was made, it bumps up the hazard rating for glyphosate products, so that means we look more carefully at potential replacements.”

Both Geiger and DeCaro noted it is difficult to find glyphosate alternatives that are less dangerous. If Seattle decided to bump glyphosate up to Tier 1, the city likely would have to weed by hand or turn to alternative systemic herbicides — a challenge, given the appealingly short time Roundup remains in soil, DeCaro added.

Though San Francisco’s Parks Department has reduced its use of glyphosate-based products by about 80 percent since the IARC ruling on glyphosate, Geiger acknowledged the controversy surrounding IARC’s decision has somewhat complicated the topic.

Allan Felsot, a professor of entomology and environmental toxicology at Washington State University, said San Francisco’s policy is “closer to some lofty ideal of the precautionary principle,” while Seattle’s policy rested on a narrative standard: “We want to use as little pesticides as possible.”

But it’s unclear to what extent Seattle has continued to push toward this standard.

“The fact that they haven’t moved or updated their hazard list tells me that they don’t want to put funding into it, or it’s not that important or they think the original hazard list should be the driver,” Felsot said. “If they want to be transparent to the public, they should update their website and show they’ve made progress.”