The Department of Pesticide Regulation (DPR) released today a draft regulation of cancer-causing 1,3-dichloropropene (aka 1,3-D, brand name Telone) that addresses only “occupational bystanders” and relies on completely different assumptions of lifetime cancer risk exposure than the law regulating the same pesticide towards children and residents near agricultural fields. The draft has already been received with anger and frustration in farmworker communities, as DPR has not justified the use of cancer risk targets that allow children and residents to be exposed to fourteen times more 1,3-D than adult workers in neighboring fields.
DPR’s draft is grounded in assumptions that “occupational bystanders” — farmworkers in fields near but not in the application site – can be exposed to air with 1,3-D concentrations of an average of 0.21 parts per billion (ppb), while at work for 8 hours a day and 5 days a week for 40 years. This cancer risk exposure level also assumes the farmworkers will not be exposed to 1,3-D outside of work, which DPR maintains will keep the occupational bystander exposure level below an average of 0.04 ppb per 24-hour day.
The 0.04 ppb per day 1,3-D exposure level is what pesticide reform advocates say should be the one standard for all California residents, as that is the legal lifetime cancer risk level determined by the Office of Environmental Health Hazard Assessment (See below). But DPR currently sets – and has announced no plans to change – the daily exposure target for children and residents at a fourteen times higher level of 0.56 ppb.
“It’s good that DPR is finally using the OEHHA findings for some. But why not all? It is not scientific to say that children – and we’re talking about mostly Latino children here – have a different lifetime cancer risk tolerance than adults. It is outrageous to say that children can be exposed to fourteen times more cancer causing 1,3-D than adults. Everybody should get the same health protective regulation that keeps 1,3-D levels below the 0.04 parts per billion per day standard set by OEHHA,” commented Jacob Sandoval, State Director of California League of United Latin American Citizens (LULAC).
Lifetime cancer risk exposure levels: “Separate and unequal”
In June of 2022, the California Office of Environmental Health Hazard Assessment (OEHHA) issued a lifetime cancer warning level or “no significant risk level” (NSRL) for the cancer-causing pesticide 1,3-dichloropropene (aka 1,3-D, brand name Telone) of 3.7 micrograms per day.[1]
Breathing air contaminated with 0.04 parts per billion (ppb) of 1,3-D exposes one to 3.7 micrograms per day.[2]
Dow Chemical, the manufacturer of 1,3-D, argued with OEHHA that the NSRL for 1,3-D should be 50 micrograms per day, the equivalent of breathing air concentrated with 0.56 ppb of 1,3-D.[3]
On January 1, 2024, DPR implemented its new regulation for 1,3-D use regarding residential bystanders, setting the target exposure level at 0.56 ppb – allowing for 14 times more 1,3-D in the air than the State’s official lifetime cancer risk warning level, and aligning perfectly with Dow Chemical’s stated desires.[4]
Today, DPR has adopted OEHHA’s lifetime cancer risk level as the target exposure limit for occupational bystanders, given assumptions that these workers are exposed to 1,3-D only during work hours. The new draft 0.21 ppb target for partial days and 40-year work-life is based upon the assumption that work-limited exposure would be equivalent to full day exposure for 70 years at 0.04 ppb.
“I’m 18 and I’ve worked in the fields for years, and I don’t understand how our State – which is supposed to be a leader in environmental justice – has created separate and unequal regulations for the same pesticide, 1,3-D,” said Rocio Ortiz, co-founder of Future Leaders of Change. “My community in Watsonville is protected 14 times less than our state scientists say is safe. We are sacrificed for Dow Chemical’s profits.”
The six pesticide air monitors the State has employed have all registered average air concentrations of 1,3-D above OEHHA’s lifetime cancer risk warning level of 0.04 parts per billion.[5]
“Working in Ventura County over the years as a substitute teacher, you hear of so many students and staff at schools near the fields who have cancer,” said Ventura area education worker Kari Aist. “Most of those kids are people of color. Rio Mesa High, for instance, surrounded by fields, is 94% people of color. Those are the kids who will continue to be exposed to 1,3-D. DPR’s regulation is a policy of environmental racism.”
According to the most recent US and California government data, an average person in the eleven California counties with a majority Latino population as compared to the twenty-five counties with the smallest Latino proportions (less than 24% — those who live in the 11 most Latino counties are 3 times as likely to be Latino)[6] lives where there is ten times more carcinogenic 1,3-dichloropropene applied per person. The two groups of counties are similar in combined total area.[7]
“Dow got what they wanted. Farmworker communities like mine got the promise of more cancer,” said Raul Garcia, organizer of the local pesticide reform group, the Tulare County Coalition Advocating for Pesticide Safety (TC CAPS). “This is another case of putting corporate profits over Latino and Indigenous health. It’s a racist regulation.”
What is 1,3-dichloropropene?
The pesticide 1,3-dichloropropene or 1,3-D was first registered in the US in 1954 (California, 1970) as a soil fumigant used to control nematodes. It has been manufactured by Dow Chemical under the brand Telone II.[8] 1,3-D is a colorless to straw-colored liquid with a sharp, sweet, irritating odor. It is a drift-prone fumigant pesticide used to kill organisms in the soil prior to planting, applied mostly on strawberry and grape fields in the Central Coast and almonds and walnuts in the San Joaquin Valley.
The fumigant is Injected into the ground or applied by drip lines and typically—but not always–covered with tarps. 1,3-D drifts initially from wind and later from volatilization for many miles at health-harming concentrations. The pesticide may also get into our water supply, as did a previous version of Telone discontinued in the late 1980s, which contained the carcinogen 1,2,3-TCP that persists in some California water systems to this day.[9]
What are the health risks associated with 1,3-D?
Acute harms include immediate exposure symptoms from high air levels due to drift: irritation of skin and nose, as well as possible slow weight gain in infants. Very high exposure to 1,3-D, such as a spill, can cause nausea, vomiting, headache, depression and damage to liver, intestines, and bladder, and difficulty breathing.[10]
The long-term health threats from chronic exposure to even tiny amounts of 1,3-D over time can cause cancer, damage to the lining of the nose, and may pollute groundwater. 1,3-D is listed as a Prop 65 carcinogen and a Toxic Air Contaminant by the State of California.[11]
1,3-D is banned in 34 countries,[12] but not in the US. The pesticide was prohibited in California between 1990 and 1995 after high air concentration levels were recorded in the Central Valley.[13]
Angel Garcia, Co-Director of Californians for Pesticide Reform said, “Our regulations should be driven by health-protective science. If DPR can get away with manipulating their regulations so they avoid the conclusions of our State’s own toxicologists at OEHHA, well, they’ll do it again and again. This is Trump’s approach to regulation – profits before people. We must resist that and insist that science drives policy in California and right now on 1,3-D.”