Poet Karl Kempton is familiar with slow-burning change.
From 1986 to 2005, he fought against methyl bromide drift emanating from a commercial strawberry farm in Oceano near the home Karl still shares with his wife, Ruth.
“We started to notice the correlation between spraying and symptoms,” Karl said. “Headaches, dizziness, lethargy. We didn’t realize until later that our daughter had two cases of pneumonia, both of which were caused by drift.”
He and Ruth, both in their 80s, have lived in the same house on Grell Lane for nearly 45 years.
The farm’s changed. With methyl bromide banned in 2005 and ultimately retired from all California strawberry fields by the end of 2016, new owners transformed the 28-acre South County plot into the organic, pesticide-free Halcyon Farms.
But Karl is now elbow-deep in another fight—one that’s laced with classified carcinogens like chloropicrin and 1,3-dichloropropene (1,3-D) used as soil fumigants by farming operations in southern San Luis Obispo County and neighboring northern Santa Barbara County.
Almost colorless, the chemicals are applied to soil before crops are planted to boost soil health and combat pests. These fumigants break down into elements naturally used by plants like carbon, chlorine, nitrogen, and oxygen. Once dissipated, they don’t leave a residue in the soil, subsequently leaving no trace in the plant either.
But chloropicrin and 1,3-D are severe irritants. After application, they don’t necessarily stay where intended and can drift in the air. According to research in the 2017 Journal of Integrative Agriculture, exposure to chloropicrin and 1,3-D can potentially lead to environmental damage and health issues.
Short-term inhalation of 1,3-D after a tank truck spill caused mucous membrane irritation, chest pain, and breathing difficulties, according to a report from the U.S. Environmental Protection Agency. Chronic long-term side effects of exposure include skin-sensitization. Two cases of histiocytic lymphomas and one account of leukemia were reported in emergency response personnel exposed to concentrated 1,3-D vapors during cleanup of the same tank truck spill.
Chloropicrin—once used in concentrated form as tear gas by German forces in World War I—can irritate the nose, throat, mouth, and lungs. It can also cause headaches, nausea, vomiting, and diarrhea, according to the Centers for Disease Control and Prevention.
Last June, the Kemptons were among 33 Oceano neighbors who believe they were exposed to fumigant drift from farms that surround the unincorporated town. Symptoms included migraine headaches, nausea, respiratory issues, and indications of the flu.
“Crows and owls no longer were seen in a resident’s trees,” Karl said. “For nearly a month up to … April 20, eastern Oceano and western Halcyon residents reported no honey bee activity.”
For months, Karl has alerted his neighbors and friends living within a mile of commercial agriculture operations about possible fumigant spraying and pesticide applications.
He saidhe’s newly optimistic thanks to the California Department of Pesticide Regulation’s rollout of a statewide notification system called SprayDays. It provides information online and through email and text message notifications sent 48 hours before the intended use of soil fumigants and 24 hours before the intended applications of other restricted pesticides on farms within a square mile.
County and state officials don’t agree with Karl’s assessment of the issue and are working to assure the community that the current regulations around chloropicrin and 1,3-D are enough to keep health risks at bay.
Cal Poly Strawberry Center Chair Gerald Holmes told New Times that fumigants are expensive to apply, are injected deep into the soil, and are not sprayed above ground using spray rigs. Per state regulations, farmworkers aren’t allowed in fields during and after fumigation for several days.
Holmes also serves on the steering committee that worked on a Department of Pesticide Regulation-commissioned report conducted by the California Council on Science and Technology (CCST).
“According to the CCST study, more than $100 million has been spent on research into fumigation alternatives,” Holmes said. “Strawberry farmers have invested more resources than any other farm group in the world in the search for solutions that address problems related to soil-borne pests and diseases.”
The Strawberry Center also studies chloropicrin and related fumigants as part of integrated disease management research. Researchers like Holmes found that chloropicrin when combined with 1,3-D is highly effective at eliminating charcoal rot and a type of fungal disease in strawberries.
“Our work also looks at how to reduce total fumigant use while maintaining plant health and yield,” Holmes said.
Many farmworkers, social justice and environmental groups like Californians for Pesticide Reform, and people living near ag operations like Karl want the Department of Pesticide Regulation (DPR) to phase out chloropicrin and 1,3-D.
Karl hopes that if he keeps pushing the issue, one day maybe state officials will ban pesticide and fumigant use on farms.
“I know I’m not going to be able to, or even a group of us, stop this chemical strawberry production. This is about alerting people,” he said. “Before March of this year, the Ag Commissioner’s Office was telling everybody everything is safe beyond 50 feet of a field. … There has been enough pressure on the state that they’re admitting drift is possible up to a mile.”
Speaking up
This year, there was hardly a full month where the Kemptons feel they haven’t been sick in some way from chemical drift.
In frequent emails to the county Ag Commissioner’s Office and South County Supervisor Jimmy Paulding, Karl has repeated similar symptoms.
“Here we are again. After the rains, pesticides applied. We have no idea where. Residents across Oceano complaining of symptoms of exposure,” he wrote in a Nov. 27 email. “My wife and I had onset of near sick headache same time two days ago. I’ve been headachy all week.”
Ruth, a retired wheatgrass grower, told New Times she counts her blessings whenever she’s healthy. The 83-year-old uses an under-the-tongue homeopathic remedy called Nux Vomica to keep the “hangover-like” nausea in check.
“It helps, it levels you, but I can’t drive a car, I can’t go anywhere,” she said. “My days are precious to me. … I just stay home. My constitution is different than his [Karl’s], like my diet is different, but we both have symptoms that are so similar. … It’s not a really pleasant way to live.”
Data from the SLO County Agricultural Commissioner’s Office showed that chloropicrin and 1,3-D have been applied in fields in and beyond Oceano.
From January to September 2025, South County-based Talley Farms and BlazerWilkinsonGee in Nipomo combined applied roughly 3,300 gallons of Telone II—a brand of multipurpose liquid fumigant with the active ingredient 1,3-D—across around 340 acres of farmland. According to data, the farms used Telone II to treat soil that eventually bore carrots and napa cabbage.
Over the same time period, to produce strawberries and summer squash, BlazerWilkinsonGee, Eat Sweet Farms, Wish Farms, Santillan Farms, BuenaVentura Ranch, Berry Valley Farms, Vazquez Farming, Mesa View Produce, Agro-Jal Farms Enterprises, LC Farm Service, and JMC Farming combined applied nearly 125,000 pounds of Tri-Clor EC fumigant with the active ingredient chloropicrin across almost 635 acres of soil in the Oceano and Santa Maria areas.
Some of these farms are near where the Kemptons live, with one of the closest operations being an Eat Sweet Farms operation less than a mile away on Highway 1 and Tierra Nueva Lane that uses chloropicrin.
Some of the Kemptons’ neighbors, like Robert and Melanie Sachs, claimed that while they’d noticed some symptoms themselves, they didn’t chalk them up to being drift-related until they spoke with Karl.
“My eyes would begin to burn outrageously, and then 20 minutes, half an hour later, it would sort of subside,” Robert said. “The only other time I would say I noticed that is, unfortunately, driving through the agricultural fields along the 227 up to San Luis Obispo.”
For his wife, Melanie, the move to their Oceano home roughly a decade ago marked the onset of the worst bout of eczema she said she had ever gone through.
“At first I thought, ‘What am I eating differently?’ or if I’m in a garden, ‘What am I touching differently?’ It was so completely random, I couldn’t really say,” said Melanie, a former educator in the spa and beauty industry. “Then I started to wonder if it was actually sprays. … In Eastern medicine, lungs and skin are very closely connected.”
Contacting the county Ag Commissioner’s Office—the bridge between constituents and the state that’s responsible for protecting the environment and the public’s health and safety—hasn’t gotten them anywhere, according to the Kemptons and the Sachses.
“When I’ve spoken with them, they’re completely cordial and basically say, ‘We can do nothing; this is a state decision,’” Melanie Sachs said.
Former competitive swimmer 41-year-old Holly Hetherington, who lives off 21st Street in Oceano, told New Times that she and her family began experiencing strange health issues almost as soon as they moved to the area four years ago.
A lifelong athlete who also played water polo growing up, Hetherington surfed, kayaked, and hiked multiple days a week. She described herself as the healthiest she had ever been 10 years ago when she was pregnant with her son.
Now, Hetherington dedicates a lot of time to tracking the days she, her son, and her aging parents fall sick. She also monitors a Facebook group called San Luis Obispo Coalition for Pesticide Reform, where locals report potentially drift-related symptoms and post the feedback they receive from the county.
“My son had a swim meet, and he was struggling just to do one lap,” she said. “My son is a very strong swimmer. It was really weird to see him in the pool trying to race, and he could barely get his arms out of the water.”
Hetherington said there were days she also felt lethargic, so much so she couldn’t get out of bed and missed work as a massage therapist. Her mother has had three severe falls since the family moved to Oceano—a result of off-balance walking because of dizzy spells.
“We’ll be dizzy for three or four days, maybe a week at a time, and then we’re fine,” Hetherington said.
In September, she noticed her usually active dog suddenly became sluggish, spending three days lying around the house.
Despite keeping all their doors and windows closed and running multiple air purifiers in their house, Hetherington and her son are still compelled to spend time outdoors because of yard work and just being a boy who likes to play. Their house is directly in the middle of two farms, and about half a mile away from the operations along Highway 1.
Hetherington has spent thousands of dollars on private doctors for consultations and blood work trying to find the reason for the health issues. She’s always hit dead ends.
“There’s a special doctor in Santa Maria who deals with environmental chemical exposure, specifically for field workers, where if they’re experiencing symptoms, you can go there and get panels, but you have to be a field worker,” she said.
College freshman Christian Guerrero avoided doctors altogether when he was a Grell Lane resident in Oceano, but he said he experienced sore throats, runny noses, and unusual headaches. He started paying more attention to health issues a year ago.
“For me, someone who doesn’t get headaches a lot, it was weird, and then we found out that they had been spraying. So it’s easy to make the connection between the two,” he said of the soil fumigant application. “They spray at night, and at night I sleep with my window open most of the time in my room.”
Once, a headache hit Guerrero so severely, he missed his morning classes at Arroyo Grande High School but managed to make it in time for an important AP test later that day.
He opted not to go to the doctor because he never did in the past when he got similar symptoms. Since he moved out of Oceano for college, Guerrero’s health has changed.
“I am not having headaches, I am not having random, long-lasting symptoms of a runny nose or a slightly sore throat,” he said. “Generally all of those symptoms have disappeared.”
Those who still live on Grell Lane, like the Kemptons, must grapple with other challenges. Karl’s insurance, for instance, doesn’t pay for the $150 blood tests he’d like to take when symptoms flare up.
“When calling in a complaint with symptoms from long-distant drift exposure to [the] county Agriculture Office, their questions asked remain restricted to decades-old questions, ‘Did you smell or see anything? Did you get a blood test? Did you see your doctor?’” he said. “One cannot see nor smell long-distant drift unless epic. And everyone has a different response or responses. Many symptoms don’t appear until days after exposure.”
Clearing the air?
A peer-reviewed study from 2019 determined that the U.S. lags behind other agricultural nations in banning pesticides. Chloropicrin is banned in 43 countries, while 40 countries have banned the use of 1,3-D, according to the consolidated list of banned pesticides compiled by Pesticide Action Network.
In California, the DPR partnered with the Office of Environmental Health Hazard Assessment to install mandatory buffer zones between 1,3-D application areas and workers laboring in adjacent fields. The new regulations also include ongoing evaluation of exposure risks and build upon restrictions that went into effect in 2024 to protect residential bystanders.
If approved by the Office of Administrative Law, the DPR’s new rules will go into effect in January 2026. The regulation is still under review.
DPR spokesperson Amy MacPherson told New Times that 1,3-D is still in use based on results from the multi-phase independent study commissioned by the department and conducted by the California Council on Science and Technology.
“The study found that there is no drop-in replacement for 1,3-D,” she said. “Additionally, the study looked at 1,3-D use in the European Union and found many countries that restrict these fumigants still allow their use under permit systems. California employs a comparable system to require review applications before they can occur.”
Pest management, MacPherson added, is critical to maintain food supply and to protect public health in California. The department works on mitigating risks from pesticide use and streamlining the availability and adoption of safe, effective, and sustainable alternatives.
“We take public input seriously and are committed to protecting the health of all Californians, including farmworkers,” MacPherson said. “DPR evaluates all pesticides for human health risks before they can be used in California, with a focus on protecting the most sensitive populations, including children. Our air monitoring network is located in areas with the highest pesticide use to collect information on real-world exposure conditions.”
But air monitoring doesn’t take place in SLO County. The DPR picks counties and communities for air monitoring depending on where pesticides and fumigants are most used, how many vulnerable people live nearby, how wind affects pesticide drift, and whether they already have effective equipment in place.
Two SLO County communities, Oceano and Callender, are included in the department’s analysis but fall low on its priority list compared to areas in Kern, Tulare, Monterey, and Fresno counties and the Santa Maria Valley.
Oceano and Callender ranked 28 and 30, respectively, for organophosphates (primarily used as pesticides). Callender also placed the lowest on the list of the 30 communities picked by the state department for highest fumigant use.
Neighboring Santa Maria showed greater agricultural pressure and environmental justice concerns, and more detections, prompting air monitoring in the area.
Local officials find Karl’s complaints difficult to respond to.
Fourth District Supervisor Paulding said there’s little that can be done to help them because of the limited authority awarded to the ag commissioner under state law. Chloropicrin in its gaseous state is more difficult to sample using conventional pesticide drift testing methods, he added.
“Had there been any tarp failures or off-gassing at a measurable level, staff believe these events would have resulted in multiple complaints from residents who live closer to the field in question, which has not occurred to my knowledge,” Paulding said. “At one point, DPR assessed that the symptoms Karl reported do not align with typical chloropicrin exposure, which tends to cause acute, not lingering, health issues.”
SLO County Deputy Ag Commissioner CeRae Speidel told New Times that the office has received 51 calls so far in the calendar year complaining about drift or to ask questions about what chemicals were being used.
Once a complaint is lodged, the Ag Commissioner’s Office starts an investigation that involves interviews with the person complaining, the grower, and the pesticide or fumigant applicator. Subject to all the laws and regulations, growers can use the concerned chemical if it’s legally registered and labeled appropriately as a pesticide or a fumigant.
Calls have been increasing in general as more housing developments crop up near ag operations, according to Speidel.
If a medical doctor examines someone who they believe has been exposed to pesticides or fumigants, they’re required by law to report that to the DPR within 24 hours. The department then flags the county where the exposure incident allegedly took place, requiring an investigation.
“I can tell you right now that probably 95 percent of them are from people who are using cleaners in their home and they mix bleach and Lysol or something like that. Depending on how they’re using those products since they have an EPA registration number, they could be considered a pesticide if they’re using them for disinfecting versus cleaning,” Speidel said. “We’ve conducted four investigations in relation to Karl and one other person concerned, and we didn’t find any violation to pesticide laws or regulations in our investigation.”
Grower-Shipper Association of Santa Barbara and SLO Counties President Claire Wineman told New Times that she feels confident and reassured by the regulations in place for chloropicrin and 1,3-D.
“I just want to re-emphasize that there’s a robust regulatory process,” Wineman said, “and that with the best available technologies, these materials are still very important to commercial agriculture production.”
Regulation response
Wineman’s response is one that Californians for Pesticide Reform Campaign Director Mark Weller is accustomed to, even though the nonprofit isn’t in touch with the Central Coast chapter of the Grower-Shipper Association.
“We have heard the same line from other Grower-Shipper groups, and just about every other Big Ag group. They say things like: ‘California has the most restrictive regulations on pesticides in the world, so there is no need to worry,’” he said. “Of course, to be registered in the European Union, the pesticide companies have to submit evidence that their products are safe. They have not been able to do that with 1,3-D and chloropicrin.”
Unlike following what’s called a precautionary principle, Weller said, the standards are completely reversed in California and the broader United States—people must first prove pesticides and fumigants are dangerous before they’re banned.
“As with tobacco companies a generation ago, pesticide companies do their own science and they present that,” Weller said. “Those are usually the studies the government uses to decide whether or not to register or approve the use of these pesticides.”
Californians for Pesticide Reform—which pushed for the nation’s first pesticide alert system, SprayDays—criticized the DPR’s new proposed rules at a Nov. 18 statewide farmworker community press conference.
Instead of banning 1,3-D, the group said, the department is creating weak regulations.
“That’s one of our biggest concerns, because the regulation is supposed to keep our exposure to 1,3-D to a level that is actually 14 times higher than what our own state toxicologists say is safe,” Weller said.
The Office of Environmental Health Hazard Assessment (OEHHA) toxicologists calculated a safe exposure level based on the most recent health protective science: 3.7 micrograms per day, or 0.04 parts per billion (ppb) in the air. But the department went with 50 micrograms or 0.56 ppb as the “target” concentration—also supported by Dow Chemical, which makes 1,3-D-based fumigants.
Weller thinks it’s a realistic long-term goal to achieve bans on carcinogens like 1,3-D and chloropicrin, and in the meantime, he said that ag commissioners can expand buffer zones for fumigants that currently exist around schools from a quarter mile to a mile. The nonprofit also thinks that the state can provide incentives to growers who have fields near schools to start farming organically, at least in those areas.
“They just choose not to [grow organically] because it’s cheaper,” Weller said. “They can make more money because you can sometimes get three fields’ worth of strawberries in a year rather than just two, for instance.”
Current regulations don’t allow fumigants to be used within a quarter mile of a school site Monday through Friday, from 6 a.m. to 6 p.m. Fumigants also can’t be used when school classes are scheduled or when day care facilities are open within 36 hours following fumigation. Implemented in 2018, these regulations also require annual notification from the grower to nearby schools.
To Californians for Pesticide Reform, the regulations assume farmworkers only work from 8 a.m. to 4 p.m., that people aren’t exposed to 1,3-D before or after work, or that it could affect kids living near fumigated fields and retired adults in homes where the chemicals drift.
“DPR has failed miserably, and we believe—by ignoring OEHHA’s finding—purposely, to protect farmworker communities from cancer,” Weller said. “It not only ignores OEHHA’s scientific findings, by allowing such harm to children who are overwhelmingly Latino and Indigenous, it is racist.” ∆
Reach Staff Writer Bulbul Rajagopal at brajagopal@newtimesslo.com.
This article appears in Dec 4-14, 2025.