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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So Justin Verlander is calling it quits, effective at the season’s end.
There’s Padres-related history to explore with Verlander, 43.
With it comes many groans.
San Diego passed on Verlander as part of the infamous, franchise-rocking decision to draft Mission Bay High School’s Matt Bush with the first overall pick in 2004.
Had the Padres chosen Verlander and tweaked the Old Dominion alum’s delivery, as the Tigers did soon after selecting him No. 2 overall, the best innings-eater of his generation could’ve headed San Diego’s rotation for many years.
As a National Leaguer, Verlander would’ve pitched against pitchers, rather than designated hitters. His annual ERA would’ve fallen by about a half run, per DH and no-DH data of that time.
The Padres would’ve boasted a generational monster atop their rotation as soon as 2006, when Verlander won the American League rookie of the year award with Detroit, while the San Diego rotation featured next year’s NL Cy Young winner, Jake Peavy.
Recall also that Petco Park, from its opening in 2004 until its remodel in 2012, played as big as Yellowstone National Park.
Not that the DH rule greatly impeded Verlander, a nine-time All-Star.
Many times over, the ace rewarded Tigers general manager Dave Dombrowski and scouting director Greg Smith for drafting him one spot after Kevin Towers and Bill Gayton — their options reduced by Padres owner John Moores’ stated opposition to drafting Scott Boras-assisted prospects Jered Weaver and Stephen Drew — selected Bush, the easy-to-sign but troubled shortstop turned pitcher.
Verlander helped Detroit reach its first two World Series in decades. He led the league in innings three times as part of chewing up 200-plus innings in eight consecutive seasons.
Dombrowski had displayed an unwavering faith in betting big on hard throwers.
Unfazed by power-righty Kyle Sleeth breaking down soon after he took him third overall in 2003, Dombrowski and Smith, a former Padres scout, became dead set on taking Verlander if the Padres didn’t.
Why didn’t Towers and Gayton choose Verlander?
Foremost, the Padres generally didn’t like him as much as the Tigers did.
In fact, they preferred Weaver and Drew.
But Moores all but blocked his scouts there. He was openly critical of their adviser, Boras, saying he didn’t trust him. The two had clashed in the Kevin Brown talks that ended with Brown joining the Dodgers, months after Brown had led the Padres to the 1998 World Series.
Moores was subjected to other kinds of pressure, too. Legal complaints had delayed Petco’s construction. Those complaints all failed in court. But in the interim, the price of steel rose. Padres ownership bore that cost.
Even though Moores’ baseball staffers whiffed on Verlander and failed miserably in choosing Bush, Moores put them in a tough spot. He in effect removed two players who would both pan out as big leaguers.
Someone with the Tigers correctly foresaw that shortening Verlander’s stride would sharpen his control. Untroubled by his 21-18 college record and bursts of subpar accuracy, the Tigers’ duo touted the 6-foot-5, 240-pounder’s “electric” combination of size, velocity and a powerful curveball.
Signing Verlander wasn’t easy.
David Verlander, the pitcher’s father and a union organizer with experience in sticky negotiations, said a contractual impasse led him to negotiate directly with Smith, leading to a deal, per CWA-Union.org.
The sides agreed on a $3.12 million signing bonus, which was less than the $3.15 million bonus the Padres paid to Bush, who was advised by Jeff Moorad.
The Boras-advised Weaver and Drew, who went 12th and 15th to the Angels and Diamondbacks, respectively, got $4 million apiece — but they and Verlander each got major league contracts, increasing the value of all three deals.
It wasn’t until close to the 2005 draft that Weaver was signed. He nonetheless returned great value to the Angels.
Verlander went on to pitch for the Astros after GM Jeff Luhnow obtained him at age 34 from Detroit.
Verlander became a better pitcher with Houston, benefiting from the tech-and-data-driven edges the Astros provided him. Verlander embraced high-speed camera data, eventually dropping his two-seam fastball and limiting his rising fastball to high in the zone. Prodded by high-speed imagery, he adjusted his slider grip.
He won his second and third Cy Youngs with the Astros, and now stands 266-159 with a 3.33 career ERA in nearly 3,600 innings.
For baseball’s hungriest fanbase, he represents a case of what might have been.
RAMONA (CNS) – Four rare western spotted skunks were released back in the wild after weeks of rehabilitation and socialization at the San Diego Humane Society’s Ramona Wildlife Center, officials announced Wednesday.
The successful release marks a major milestone for a species rarely seen in wildlife rehabilitation. The group included one orphaned skunk that was flown more than 400 miles by Flying Tails Animal Rescue from Sierra Wildlife Rescue in Northern California to join an orphaned group in Ramona, according to the SDHS.
The four skunks were returned to a carefully selected, remote habitat in Valley Center after reaching the necessary weight and developmental milestones to thrive on their own.
Western spotted skunks are a rare sight for the Humane Society’s Project Wildlife team. While the wildlife center typically handles hundreds of striped skunks each year, admitting six spotted skunks from different litters in one season is unusual. Spotted skunks are generally found in remote forested areas and are not as common in urban neighborhoods, officials said.
“We have never seen this many western spotted skunks in a single season before,” said Autumn Welch, wildlife operations manager at the Ramona Wildlife Center. “Because they are more reclusive than striped skunks, they require very specific care and even more secluded release sites to ensure they can stay wild.”
Socialization is critical for orphaned spotted skunks. During their stay at the Ramona Wildlife Center, the group became a bonded unit — exploring, digging and sleeping together, according to SDHS officials. Experts say these social cues prevent habituation to humans and teach the orphans natural skunk behaviors.
While four members of the group have returned to the wild, two spotted skunks remain in care at the facility. The smallest skunk was moved to an outside pre-release habitat and introduced to a slightly older skunk in late June.
Wildlife officials said by keeping the pair together, the wildlife team ensures the younger skunk will have a companion to learn from until they are both ready to be released, likely within the next month or two.
Anyone who finds an injured, sick or orphaned wild animal is encouraged to visit sdhumane.org/wildlifehelp or call 619-299-7012.
Copyright 2026, City News Service, Inc.
SAN DIEGO (FOX 5/KUSI) — A 33-year-old man was sentenced Tuesday to 325 years to life in prison for sexually abusing two 6-year-old girls, in addition to a slew of other felony sex abuse charges, according to the San Diego County District Attorney’s Office.
Christopher T. Gardner was convicted of 15 felony sex abuse charges, which included molesting the two girls, who were relatives of his, over a five-year period.
The abuse reportedly first came to light when one of the victims told a friend in confidence during a sleepover that she had been touched inappropriately. The friend then told her mother, who contacted law enforcement.
After Gardner was arrested, a third victim came forward, who was also a relative. Now a young adult, the victim said that when she was 7-8 years old, Gardner sexually assaulted her.
During the nine-day trial, the first two victims reportedly testified to multiple vulgar acts of sexual abuse by Gardner.
“Predators who rob children of their innocence and inflict lifelong trauma do not belong in our communities,” DA Summer Stephan said. “This sentence sends an unmistakable message to abusers: you will be held accountable. I am deeply grateful to our specialized sexual abuse prosecution team for their dedication in bringing a measure of justice to the survivors.”
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