Scientists studying environmental pollutants tend to divide them into two distinct groups. One includes “legacy” contaminants that drew attention during the early stages of the environmental movement, like mercury, PCBs, and some pesticides. The other is a much larger class of “emerging” contaminants whose production or monitoring began more recently and about whom less is known; think pharmaceuticals, plastic additives, and flame retardants.
Effluent from wastewater treatment plants is often seen as the primary source of emerging contaminants in San Francisco Bay. But a report published in July by the Regional Monitoring Program (RMP) challenges that assumption by highlighting the importance of urban stormwater runoff as another major source of some less-studied chemicals in Bay waters.
These include ethoxylated surfactants, traditionally thought of as detergents more likely to be present in wastewater, and other compounds derived from tires and roadways, says senior scientist Rebecca Sutton with the San Francisco Estuary Institute (SFEI), who led the work.
Tire leachate is an emerging contaminant in stormwater. Photo: Ariel Okamoto
In 2016, SFEI researchers collected water samples at three sites in the Bay, each representing a different contaminant pathway: the middle Napa River (still tidally influenced) for agricultural runoff; the mouth of Coyote Creek for treated wastewater discharge; and San Leandro Bay for urban runoff. The study team also obtained effluent samples from four local wastewater plants.
Instead of searching only for specific contaminants, the researchers wanted to cast a wider net. For this they turned to a relatively new approach known as non-targeted analysis, which uses laboratory techniques called liquid chromatography and mass spectrometry to pick out chemical signatures in samples and then compare them to more than 22,000 signals for known compounds. Matches, or hits, are then further analyzed to confirm their identity with a high degree of confidence.
“Around the beginning of the 2010s, the concept of using advanced analytic chemistry to try to discover new compounds that might be in the Bay that we were not looking for came to be possible,” says Duke University’s Lee Ferguson, a pioneer of non-targeted analysis who has served on the RMP’s Emerging Contaminants Workgroup since 2006 and whose lab analyzed the samples. After a few pilots in the early 2010s, technological advances finally made a full-Bay study possible.
“It’s a very powerful technique,” Sutton says. “It can reveal things we didn’t anticipate.”
Sure enough, water samples in the study contained more than 400 unique, water-soluble chemicals including detergents and surfactants, plastic additives, pesticides, pharmaceuticals, and flame retardants.
Predictably, pesticides were the primary contaminant in water from the Napa River. Samples from the Coyote Creek site and four wastewater treatment plants contained plenty of pharmaceuticals — including antibiotics, antiepileptic drugs, antidepressants, hypertension drugs, anticonvulsants, and cardiac treatment drugs — as well as ingredients from cleaning and personal-care products.
Napa River sampling site. Photo: SFEI
But San Leandro Bay, bordered by highly urbanized and industrial sections of Oakland, Alameda, and San Leandro, harbored some surprises. It contained the greatest number of ethoxylated surfactants, potentially harmful chemicals more widely known for their use in products including shampoo, liquid soap, bubble bath, and hair relaxers.
In fact, these chemicals are also used in asphalt and automotive and industrial products. After they are deposited on parking lots, roadways, and other surfaces, rain can wash them to the Bay through creeks and storm drains.
The San Leandro Bay samples also detected compounds used in the production of rubber vehicle tires. Recent studies in Washington’s Puget Sound have shown that chemicals leaching from tires can be toxic to coho salmon.
“We keep learning about new contaminants, both in the Bay and the water pollution world in general, and the idea is to identify them as early as possible so that they don’t become legacy contaminants of the future,” says RMP lead scientist Jay Davis.
Because the research did not quantify contaminant concentrations, it doesn’t address whether chemicals are present at levels of concern for aquatic life or human health. That task will fall to follow-up studies to further investigate the prevalence and risk profile of ethoxylated surfactants, so-called tire leachate, and other emerging contaminants in urban stormwater runoff. Some of this work is already underway, initiated soon after results from the non-targeted analysis study first became clear. “The RMP spends several hundred thousand dollars per year on emerging contaminant work, and we shifted a large portion of that toward stormwater studies,” Davis says. “It has become a major focus of our work.”
Nate Seltenrich is a freelance science and environmental journalist who covers infrastructure, restoration, and related topics for Estuary. He also contributes to the San Francisco Chronicle, Sonoma and Marin magazines, the journal Environmental Health Perspectives, and other local and national publications, on subjects ranging from public lands and renewable energy to the human health impacts of climate change. He lives in Petaluma with his wife, two boys, and four ducks. www.nate-reports.com
Our magazine’s media motto for many years has been “Where there’s an estuary, there’s a crowd.” The San Francisco Estuary is a place where people, wildlife, and commerce congregate, and where watersheds, rivers and the ocean meet and mix, creating a place of unusual diversity. In choosing to tell the...
Ever since the state and federal water projects were built in the 1930s and 1940s, California has captured snowmelt in foothill reservoirs, and moved the fresh water from dam releases and river outflows to parched parts of the state via aqueducts hundreds of miles long. A convoluted system of ancient...
Though the Clean Water Act did an amazing job of reducing wastewater and stormwater pollution of the San Francisco Estuary, some contaminants remain thorny problems. Legacy pollutants like mercury washed into the watershed from upstream gold mining, PCBs from old industrial sites, and selenium from agricultural drainage in the San...
Hothouse Earth
By Ariel Rubissow Okamoto
Photo by Megan Nguyen
Nothing could be stranger than sitting in the dark with thousands of suits and heels, watching a parade of promises to decarbonize from companies and countries large and small, reeling from the beauties of big screen rainforests and indigenous necklaces, and getting all choked up.
It was day two of the September 2018 Global Climate Action Summit in San Francisco when I felt it.
At first I wondered if I was simply starstruck. Most of us labor away trying to fix one small corner of the planet or another without seeing the likes of Harrison Ford, Al Gore, Michael Bloomberg, Van Jones, Jerry Brown – or the ministers or mayors of dozens of cities and countries – in person, on stage and at times angry enough to spit. And between these luminaries a steady stream of CEOs, corporate sustainability officers, and pension fund managers promising percentages of renewables and profits in their portfolios dedicated to the climate cause by 2020-2050.
I tried to give every speaker my full attention: the young man of Vuntut Gwichin heritage from the edge of the Yukon’s Arctic National Wildlife Refuge who pleaded with us not to enter his sacred lands with our drills and dependencies; all the women – swathed in bright patterns and head-scarfs – who kept punching their hearts. “My uncle in Uganda would take 129 years to emit the same amount of carbon as an American would in one year,” said Oxfam’s Winnie Byanyima.
“Our janitors are shutting off the lights you leave on,” said Aida Cardenas, speaking about the frontline workers she trains, mostly immigrants, who are excited to be part of climate change solutions in their new country.
The men on the stage, strutting about in feathers and pinstripes, spoke of hopes and dreams, money and power. “The notion that you can either do good or do well is a myth we have to collectively bust,” said New Jersey Governor Phil Murphy whose state is investing heavily in offshore wind farms.
“Climate change isn’t just about risks, it’s about opportunities,” said Blackrock sustainable investment manager Brian Deese.
But it wasn’t all these fine speeches that started the butterflies. Halfway through the second day of testimonials, it was a slight white-haired woman wrapped in an azure pashmina that pricked my tears. One minute she was on the silver screen with Alec Baldwin and the next she taking a seat on stage. She talked about trees. How trees can solve 30% of our carbon reduction problem. How we have to stop whacking them back in the Amazon and start planting them everywhere else. I couldn’t help thinking of Dr. Seuss and his truffala trees. Jane Goodall, over 80, is as fierce as my Lorax. Or my daughter’s Avatar.
Analyzing my take home feeling from the event I realized it wasn’t the usual fear – killer storms, tidal waves, no food for my kids to eat on a half-baked planet – nor a newfound sense of hope – I’ve always thought nature will get along just fine without us. What I felt was relief. People were actually doing something. Doing a lot. And there was so much more we could do.
As we all pumped fists in the dark, as the presentations went on and on and on because so many people and businesses and countries wanted to STEP UP, I realized how swayed I had let myself be by the doomsday news mill.
“We must be like the river, “ said a boy from Bangladesh named Risalat Khan, who had noticed our Sierra watersheds from the plane. “We must cut through the mountain of obstacles. Let’s be the river!”
Or as Harrison Ford less poetically put it: “Let’s turn off our phones and roll up our sleeves and kick this monster’s ass.”
4th California Climate Change Assessment Blues
by Isaac Pearlman
Since California’s last state-led climate change assessment in 2012, the Golden State has experienced a litany of natural disasters. This includes four years of severe drought from 2012 to 2016, an almost non-existent Sierra Nevada snowpack in 2014-2015 costing $2.1 billion in economic losses, widespread Bay Area flooding from winter 2017 storms, and extremely large and damaging wildfires culminating with this year’s Mendocino Complex fire achieving the dubious distinction of the largest in state history. California’s most recent climate assessment, released August 27th, predicts that for the state and the Bay Area, we can expect even more in the future.
The California state government first began assessing climate impacts formally in 2006, due to an executive order by Governor Schwarzenegger. California’s latest iteration and its fourth overall, includes a dizzying array of 44 technical reports; three topical studies on climate justice, tribal and indigenous communities, and the coast and ocean; as well as nine region-specific analyses.
The results are alarming for our state’s future: an estimated four to five feet of sea level rise and loss of one to two-thirds of Southern California beaches by 2100, a 50 percent increase in wildfires over 25,000 acres, stronger and longer heat waves, and infrastructure like airports, wastewater treatment plants, rail and roadways increasingly likely to suffer flooding.
For the first time, California’s latest assessment dives into climate consequences on a regional level. Academics representing nine California regions spearheaded research and summarized the best available science on the variable heat, rain, flooding and extreme event consequences for their areas. For example, the highest local rate of sea level rise in the state is at the rapidly subsiding Humboldt Bay. In San Diego county, the most biodiverse in all of California, preserving its many fragile and endangered species is an urgent priority. Francesca Hopkins from UC Riverside found that the highest rate of childhood asthma in the state isn’t an urban smog-filled city but in the Imperial Valley, where toxic dust from Salton Sea disaster chokes communities – and will only become worse as higher temperatures and less water due to climate change dry and brittle the area.
According to the Bay Area Regional Report, since 1950 the Bay Area has already increased in temperature by 1.7 degrees Fahrenheit and local sea level is eight inches higher than it was one hundred years ago. Future climate will render the Bay Area less suitable for our evergreen redwood and fir forests, and more favorable for tolerant chaparral shrub land. The region’s seven million people and $750 billion economy (almost one-third of California’s total) is predicted to be increasingly beset by more “boom and bust” irregular wet and very dry years, punctuated by increasingly intense and damaging storms.
Unsurprisingly, according to the report the Bay Area’s intensifying housing and equity problems have a multiplier affect with climate change. As Bay Area housing spreads further north, south, and inland the result is higher transportation and energy needs for those with the fewest resources available to afford them; and acute disparity in climate vulnerability across Bay Area communities and populations.
“All Californians will likely endure more illness and be at greater risk of early death because of climate change,” bluntly states the statewide summary brochure for California’s climate assessment. “[However] vulnerable populations that already experience the greatest adverse health impacts will be disproportionately affected.”
“We’re much better at being reactive to a disaster than planning ahead,” said UC Berkeley professor and contributing author David Ackerly at a California Adaptation Forum panel in Sacramento on August 27th. “And it is vulnerable communities that suffer from those disasters. How much human suffering has to happen before it triggers the next round of activity?”
The assessment’s data is publicly available online at “Cal-adapt,” where Californians can explore projected impacts for their neighborhoods, towns, and regions.
The results are alarming for our state’s future: an estimated four to five feet of sea level rise and loss of one to two-thirds of Southern California beaches by 2100, a 50 percent increase in wildfires over 25,000 acres, stronger and longer heat waves, and infrastructure like airports, wastewater treatment plants, rail and roadways increasingly likely to suffer flooding.