San Diego, CA
Pollution from the Tijuana river affects air quality in San Diego, finds study
The 120-mile Tijuana River flows from Baja California into the United States and discharges millions of gallons of wastewater—including sewage, industrial waste and runoff—into the Pacific Ocean every day, making it the dominant source of coastal pollution in the region.
Wastewater pollution has been an ongoing problem for decades and is so severe that the nonprofit environmental group American Rivers recently named the Tijuana River America’s second most endangered river.
A new study from the University of California San Diego examines how pollutants in wastewater travel and are transmitted in the atmosphere through coastal aerosols.
In the study, researchers found that a mixture of illicit drugs, drug metabolites, and chemicals from tires and personal care products aerosolize from wastewater and are detectable in both air and water. The results appear in Science Advances.
The paper’s lead author, Adam Cooper, collected samples from the air and water at various points along the coast of San Diego County, including the U.S.-Mexico border, Imperial Beach and the Scripps Institution of Oceanography in La Jolla.
Cooper, who graduated last spring with a doctorate in chemistry, was a member of Assistant Professor of Chemistry and Biochemistry Jonathan Slade’s group, and collected the samples as part of a field study with Distinguished Professor of Atmospheric Chemistry Kimberly Prather’s lab.
Prather, who holds a joint appointment at Scripps Oceanography and the Department of Chemistry and Biochemistry at UC San Diego, had been studying the air pollution impacts of the Tijuana River for several years. Cooper was able to join her team’s comprehensive sampling campaign across multiple sites from January to March of 2020.
Even though the samples were taken in 2020, the findings are still relevant because little has changed in how sewage released from the river is processed. In fact, pollution from the river has been an ongoing problem for more than 50 years.
“The Tijuana River region is a very dynamic environment with implications for public health, environmental policy and international relations between the United States and Mexico,” stated Cooper.
“Ours is one of the most comprehensive studies to date investigating water-to-air transfer of these pollutants.” The study looked at two aspects of wastewater pollution: the source and the concentration of pollutants along the San Diego County coastline.
To determine the origin of the pollutants, Slade’s lab used a compound they knew came from sewage: benzoylecgonine (BZG), a stable metabolite of cocaine, primarily produced when people use cocaine and then excrete it in urine.
They found that after rainfall, BZG levels in Imperial Beach ocean water spiked in correlation with increased Tijuana River flows, while BZG levels in aerosols spiked in correlation with enhanced sea spray aerosol emissions.
Correlating 11 other pollutants to BZG in aerosols allowed the team to determine which ones behaved similarly in the environment and likely originated from the same wastewater source. The results showed a high correlation between BZG; methamphetamine; octinoxate, a UV filter used in sunscreen; and dibenzylamine, a compound used in tire manufacturing.
The second part of the study measured pollutant concentrations along the coastline in the water and air. Overwhelmingly, they found that these pollutants were higher in the Tijuana River water than in the ocean, and higher in the water and aerosols in the Imperial Beach region than in La Jolla.
Although the amounts of some pollutants, like cocaine, were minuscule, others were more prominent, like octinoxate, which can break down into more toxic components.
In some cases, the octinoxate levels were comparable to measurements made directly above wastewater treatment plant vats, meaning that in some ambient conditions at the coast, the concentrations of pollutants that people are inhaling can be comparable to a worker at a wastewater treatment plant.
“It’s been shown that octinoxate can degrade DNA when exposed to light,” stated Slade. “And if it’s in these tiny aerosols we’re breathing in, it can get deep into our lungs and pass into our bloodstream. That’s very concerning, especially considering the high levels at which we found it in the air.”
The study shows that the closer you are to the Tijuana River, the more likely you are to be exposed to the pollutants it carries, even though the amounts are still relatively small—on the scale of tens of nanograms per hour. This may not seem like much if your exposure is limited to a few hours, but residents living close to the border are inhaling these chemicals over years, even decades.
Many residents have complained of respiratory illness, insomnia and headaches, and several San Diego beaches have been closed almost continuously for the last three years because of high levels of bacteria from wastewater runoff.
Although the paper doesn’t draw any conclusions about the detrimental effects on the environment or human health, Slade and Cooper emphasize the need for more research, better infrastructure and cross-border collaboration.
“Often the sewage crisis is considered a water issue—and it is—but we show that it’s in the air too. Truthfully, we don’t yet know the acute health effects,” stated Slade. “But the numbers we report can be incorporated into models to help us better understand what we’re breathing in and how much we’re exposed to.”
Cooper was so influenced by his work at UC San Diego that he is now a Science and Policy Technology Fellow with the California Council on Science and Technology, working with State Senator Ben Allen.
“The solutions to the cross-border sewage crisis aren’t constrained by technical challenges,” stated Cooper. “They’re constrained by political challenges and policy issues. We have to motivate decision-makers to make the right investments.”
In addition to better infrastructure, more public awareness is crucial to improving the region’s water and air quality, including understanding the downstream effects of the products we use, such as sunscreens and tires.
“Although our study focuses on the Tijuana River, there are other notable sources of wastewater and pollution run-off in Southern California, including wastewater treatment outfalls, the San Diego River and the Los Angeles River,” said Slade, who also noted that “turbulence in rivers and streams may aerosolize wastewater, requiring further study.”
Coastal port environments are extremely dynamic and complex, but these pollution issues are not relegated just to the San Diego-Tijuana region. They pose a global hazard.
An estimated 80% of all global wastewater is untreated. Of the portion that is treated, many plants remove bacteria, but not chemical pollutants. These chemicals remain in the water, which is released into rivers, lakes and oceans, traveling around the world through waterways and in the atmosphere.
“The global surge of untreated wastewater entering lakes, rivers and oceans poses a growing health threat. Aerosolization of this polluted water exposes billions of people through airborne transmission, reaching far beyond those in direct contact and impacting countless others who inhale contaminated air that can travel for many miles,” stated Prather.
“We are continuing our studies in this region to better understand the short and long-term health impacts of inhaling this newly identified source of airborne pollution.”
More information:
Adam Cooper et al, Identifying Wastewater Chemicals in Coastal Aerosols, Science Advances (2025). DOI: 10.1126/sciadv.ads9476. www.science.org/doi/10.1126/sciadv.ads9476
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Pollution from the Tijuana river affects air quality in San Diego, finds study (2025, May 28)
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Sez Me …
We should have known better. I’m an idiot for not guessing that making sense out of the College Football Playoffs would be about as pleasurable as getting a colonoscopy with a rusted rake left out in the snow.
As far back as I can remember — and those of us over 50 know this Unsocial Media’s Generation’s memory goes back a week — I’ve been shouting from the rooftops that we must have a college football playoff.
(Although I will admit to not spending much time on rooftops lately, now that TV antennas have gone the way of the carburetor.)
A four-team tournament was a good start, but obviously not large enough. When it went to 12, it appeared to be the ideal number. Those who bitched over not making the final four now were going to get a chance to prove themselves on the field of play.
The big deal today is Notre Dame being left out of the top 12, with James Madison and Tulane getting in because the system allows conference champions. Notre Dame is independent, thus no conference — in football only.
This is a real shame.
As you know, I’m no fan of the Irish. Up to this minute, they’ve been privileged beyond belief. Both ND and Miami finished with 10-2 records, but the Irish lost to the Hurricanes in the opener, and by the time the selection committee made its final list, it took head-to-head into account. Which is the way it should be, when both teams finish with the same records.
Pouting Notre Dame athletic director Pete Bevacqua, whose school has chosen not to appear in a menial (for them) bowl game, says few schools ever have had a more successful run than ND.
The programs the Irish beat in that 10-game span had an overall record of 55-65. Historic.
Despite all that, ND was one of the few teams that seemed capable of winning the national title. It certainly belonged in over Alabama, but the SEC has special powers.
The Irish will be in it soon enough. I suspect the tournament will balloon to 16 teams. The problem now is that with NIL and rampant portal transferring, we have parity as we’ve never had it before. And that’s not a good thing. It will be much harder for the James Madisons of the world to make it.
But this isn’t basketball. It doesn’t deserve to be in.
The Dukes lost 28-14 to Louisville, their only power conference opponent (and not a good one). And they’re a three-touchdown underdog to Oregon in the tournament. Notre Dame and Oregon would be close.
But that’s just too damn bad. …
Indiana’s Curt Cignetti is the most dour head football coach at any level I’ve seen. You can sit this guy down in front of “Blazing Saddles” and he’s watching “Camille.” …
Curt isn’t winning the national title, but he’s done a helluva job at Bob Knight’s school. Come to think of it, he’s Bob without the chair. …
The Eagles’ Nick Sirianni, who is leaning at the tape as the worst head coach to win a Super Bowl, worked all week with the Philly offense. Jalen Hurts had a 31.2 passer rating vs. the NFL Team That Used To Be Here on Monday night. Smokey Gaines, where are you? That’s 31.2 more than a dead man. …
Daiyan Henley tackling Tony Jefferson after his overtime pick vs. the Eagles was wise. But because it was OT, even if Jefferson had fumbled it away and Philly recovered, the game would have been over. No extra possessions allowed in OT. …
Philip Rivers, 44, who last played football in 2020, should stay as far away from the NFL as humanly possible, perhaps have another child. Alas, he can’t help himself. …
Philip has been signed by the Colts, moving his Hall of Fame eligibility up five more years — which could mean a few more kids. …
But he’s going to play. Probably Sunday. You know that. …
In fact, I’m certain Philip eventually will become the first great-grandfather to play in The League. …
Philip has to be in better shape than Justin Herbert, no? …
Jim Harbaugh is right. Herbert is a superhero. …
Patrick Mahomes is a great quarterback. But he is a lousy quarterback under pressure. Always has been. Except there’s more pressure now. Still, if the Judases give him time to throw Sunday, adios J’s. …
With that offensive line protecting Herbert the way Sarajevo cops guarded Archduke Franz Ferdinand, it remains a wonder the Judases can win a game. But it’s December, when defense matters. …
Told you. Joe Burrow is Andrew Luck waiting to happen. …
The only games the NFL should play on Christmas Day are the ones the athletes and coaches bought for the kids to open. …
Todd Bowles, we know you can cuss. Try coaching better before driving the bus over your players. …
Bill Johnston, for 39 years publicist for the NFL Team That Used To Be Here, and serving for the last nine with the Padres, is retiring. He learned from the best, Rick Smith, a bulldog, and Bill had that attitude as he battled relentlessly beside wife Ramona through her two-decade battle with Huntington’s Disease. One of the finest men I’ve known. …
Sherrone Moore has been fired as Michigan’s football coach because of an inappropriate relationship with a staff member. Sherrone then lost it and got thrown in stir for stalking and home invasion. Lane Kiffin still has time to change his mind and go to Ann Arbor. …
The Michigan job is near the top. Great history. Unlimited resources. …
USC’s Makai Lemon was the best receiver I saw all year. So he won the Biletnikoff Award. Amazing. Others agreed with me. …
The Padres have signed reliever Daison Acosta. Now there’s one with some teeth. …
The Padres and Diamondbacks will meet in Mexico City April 25 and 26? Why? Plenty of Mexican food here, and Richardson’s in Phoenix is the best Mexican in America. OK, international games are stupid. …
Now in his second year in the Fox booth, Tom Brady is getting better as he tries to earn all of that 10-year, $375 million salary. It’s what happens when Bill Belichick tells him what to say. …
Happens every week. During Steelers-Ravens, the officials screwed the Ravens into Fort McHenry. …
Officials finally got something right. They called 19 accepted penalties on the pathetic Falcons Thursday night vs. the Bucs. Atlanta still won. …
Hey, Bicycle Mayor and His Ham & Eggers: Have you taken a ride south on Kettner toward the I-5 South onramp, featuring the Rick Schloss bump? Hope you have four-wheel drive. What a disgrace. Welcome to San Diego, rental car users. …
Jeff Kent was a good baseball player. I never considered him a Hall of Famer. Still don’t. …
Army-Navy. Fastest game. As though Randy Jones were pitching. …
I was at the 1990 World Cup in Italy, which, I believe, makes me eligible for the FIFA Peace Prize. …
How can whistles be that clean?
San Diego, CA
San Diego State Edge Plans to Enter Transfer Portal After Rob Aurich Takes Nebraska Job
Nebraska’s defensive line overhaul under new defensive coordinator Rob Aurich is already appearing to create potential landing spots for veteran defenders across the country.
Less than a week after news broke that Aurich would be Nebraska’s next defensive coordinator, San Diego State junior and former three-star edge August Salvati announced his intentions to enter the transfer portal when it opens in January.
While it instantly creates a potential connection between the soon-to-be senior and his former coach, Salvati becomes a name to watch for a Nebraska program that is believed to be taking an aggressive approach to shoring up both lines of scrimmage over the offseason.
For the veteran defender, the move comes after his most productive collegiate season to date. With that in mind, here’s everything you need to know about the Clearwater, FL native
In 2025, Salvati totaled six tackles, 3.5 sacks, and one interception during the regular season while helping Aurich boast the nation’s No. 7 total defense for the year. His snap count was modest, but the production still stands, as Salvati’s sack total would instantly become a team-high on Nebraska’s squad during the same timeframe.
To put in the context the stark contrast between the Husker’s and Aztec’s ability to affect the passer, Salvati’s 3.5 sacks raked fifth highest on his team this fall. Three other San Diego State defenders totaled more than 6.5 sacks alone.
With that in mind, Salvati’s role under Aurich in the Golden State was situational, and he appears to be looking to parlay his success this year into a more impactful one in 2026. For a Nebraska program that needs all the help they can get, the veteran defender likely becomes attractive to Matt Rhule’s staff.
Salvati’s career mirrors that of many players in the modern era of college football. Out of high school, the 6-foot-3, 245-pound defender took his talents to Kilgore College in Texas. There, his first season of collegiate ball became a resounding success. Salvati totaled 29 tackles, 7.0 sacks, and a fumble recovery on his way to earning SWJCFC honors.
He then transferred to Florida Atlantic in 2024. In his lone season in Boca Raton, Salvati appeared in one game without recording any stats. After the season, that is where his timeline connects him to Aurich. Entering the transfer portal around this time last year, the, at the time, junior moved across the country to join Aurich’s Aztec squad, and the rest is history.
Under Aurich, San Diego State took a tremendous jump. In a season that saw the Aztecs go 9-3, Aurich oversaw a defense that allowed just 266.7 yards per game while holding opponents to 12.6 points on average.
His group slashed its yardage allowed by more than 154 yards per game en route to shutting out three different opponents on the year. The Aztecs also excelled in the area that Nebraska’s defense struggled in this fall. The Huskers totaled 19 sacks in 12 regular-season games, compared to the Aztecs’ 32. San Diego State also recorded the best red zone defense in all of college football, whereas Nebraska was slotted second-to-last.
On paper, the hire appears to be one in which Rhule struck gold. Every stop that Aurich has been, his teams have improved, and players have developed into all-conference level athletes. That’s yet another area the Huskers have struggled at in recent years. But from Aurich’s addition and impending announcements regarding Nebraska’s defensive line coaching position, the Huskers seem to be attempting to turn the page in that regard.
Whether Salvati does indeed end up in Lincoln next fall, or is just another name potentially linked to the Huskers’ program, Nebraska’s defense seems to be in good hands moving forward. Aurich has repeatedly proved himself to be resourceful and now has the resources needed to make an even bigger jump. Believe it or not, the Huskers are significantly more aligned in the NIL and revenue-sharing era of college football than any of their new defensive coordinator’s previous stops.
While that doesn’t mean the Huskers now have an unlimited budget, it does mean Aurich will not be limited while making additions over the coming months. He’s shown he can turn role players into NFL Draft picks, and now he’ll be asked to do the same at Nebraska.
For now, Aurich gets himself adjusted to Lincoln, but before you know it, he’ll be adding his first wave of reinforcements to his squad. The transfer portal opening date is just under three weeks away; expect more news to be had as soon as it hits.
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San Diego, CA
Let the Signature Gathering Begin: Coalition Pitches Sales Tax for Border Sewage, Child Care
Two labor unions and a child care advocacy group on Friday filed a proposed countywide sales-tax hike they’ve dubbed the Protect San Diego County’s Health & Safety Act with the county Registrar of Voters in hopes of making the November 2026 ballot.
The proposed half-cent sales tax measure – which would raise a projected $360 million annually – aims to fund health care, child care, solutions to the Tijuana River sewage crisis and public safety.
The Service Employees International Union Local 221, child care advocacy group Children First San Diego and Cal Fire Local 2881 expect to start collecting signatures next month.
“We’re taking urgent action on the biggest health and safety threats San Diego County is facing – Tijuana River toxic sewage, strained 911 response, working families losing healthcare, childcare, and even the basic food they need to survive,” SEIU 221 President Crystal Irving wrote in a statement. “Our coalition is determined to give voters the power to choose a safer, healthier future and starting soon we’ll be out in every community gathering signatures and working with neighbors to protect San Diego County families.”
Proposed ballot language submitted to the Registrar of Voters Friday describes a slew of causes that proponents aim to support with a half-cent sales-tax increase. Up to 60 percent of funding – the equivalent of $261 million annually – could back child care and health services for children, health care for uninsured or underinsured people, food aid including staffing for CalFresh eligibility workers in the county, in-home health services and affordable health care.
Nearly 23 percent – or roughly $81 million annually – would go toward combating the Tijuana sewage crisis, with at least 20 percent of this share of funds directed toward infrastructure projects to “stop sewage flows from Tijuana into the United States or through the Tijuana River Valley.” The measure says the funding could also address related health issues and protect local waters from pollution.
Nearly 18 percent – or almost $63 million annually – could back public safety services, wildfire prevention and crisis response.
Proponents also capped administrative costs at 1.5 percent, or about $5 million annually.
The proposed measure also calls for an 11-member citizens oversight committee to conduct annual audits and bars spending on politicians’ salaries, lobbyist contracts or government office renovations.
The citizen-backed effort is separate from the subcommittee work that county Board Chair Terra Lawson-Remer and Vice Chair Monica Montgomery Steppe are queuing up to hash out ways the county might bring in. The county faces an estimated $300 million annual budget hit tied to federal cuts. The county is set to hire and pay consultants up to $500,000 as part of that effort to conduct polling and research on potential measures to raise taxes and other possible ways to increase revenues that may require changes to other policies.
In a Friday statement, Lawson-Remer lauded the proposed citizen measure.
“This San Diego County Health & Safety citizens initiative offers a key tool that voters could choose to support in order to defend our community and our values: to keep our water clean, to keep our hospitals open, and to make sure firefighters and first responders have the resources they need when the next wildfire hits,” Lawson-Remer wrote. “When Washington walks away, our community refuses to look the other way.”
The decision to proceed with a citizens’ measure doesn’t rule out a potential future measure pushed by county supervisors. Yet Lawson-Remer’s quick endorsement shows she’s eager to see a citizens’ group push a measure forward that only requires a simple majority for a ballot victory.
The coalition behind it will face an uphill battle to persuade skeptical voters already facing an avalanche of rising costs – and to get on the ballot in the first place.
Courtney Baltiyskyy of Children First San Diego said the coalition expects to hit the streets in January to try to collect at least 140,000 signatures. They’ll need to deliver at least 102,923 valid signatures to get on next November’s ballot.
The county coalition also expects to have some competition next November.
The coalition that includes Laborers Local Union 89, Carpenters Union Local 619, and Rebuild SoCal are rallying behind a one-cent sales tax hike for city of San Diego for infrastructure repairs, wildfire prevention, pipe repairs for clean water and more.
Both coalitions have recently circulated polls testing voters’ appetite for separate city and county measures and shared some intel.
Their intel-sharing follows the November 2024 demise of Measures E and G, separate city and countywide sales-tax proposals. San Diego politicos are skeptical voters would support two sales-tax hikes.
The results of an initial poll of city voters conducted around Labor Day on the city measure suggested both city and county measures suggested a challenging climate for proposed tax increases.
Results obtained by Voice of San Diego show 57 percent of the 776 voters polled said they thought the county was on the wrong track and 60 percent said the same of the city.
Baltiyskyy said Friday the countywide coalition believes it has a path to victory – and that support for it will grow as voters and local organizations learn more.
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