How Toxic Is Professional Pest Control? 18 Million California Treatments, Classified by Label
Key result: 97.2 percent of California’s 18.3 million structural pest control applications in 2022 used a product labelled CAUTION, the lowest of the three federal toxicity signal words. 0.61 percent used a DANGER product, almost all of it fumigation. 2.35 percent used a restricted-use product. One application in six was a rodenticide bait.
The question homeowners ask, answered from the records
“Is the stuff the exterminator sprays dangerous?” is one of the most common questions about pest control, and it is usually answered with reassurance or alarm rather than numbers. California’s pesticide use reports allow a count. Every monthly report names the exact registered product used and how many applications it covered. The state’s product reference file records each product’s label signal word, formulation and restricted status.
We joined the two for every structural pest control report in 2022 and 2023: 18,272,166 applications of 1,723 products in 2022, and 18,815,415 applications of 1,683 products in 2023.
The signal word is set by the US Environmental Protection Agency from the formulated product’s acute toxicity. DANGER means highly toxic by at least one route of exposure, or corrosive. WARNING means moderately toxic. CAUTION means slightly toxic. Products in the lowest toxicity category by every route need no signal word at all.
Signal words on the label
| Signal word | Applications, 2022 | Share, 2022 | Share, 2023 |
|---|---|---|---|
| CAUTION | 17,758,106 | 97.2% | 93.7% |
| WARNING | 279,690 | 1.5% | 2.9% |
| DANGER, or POISON and DANGER | 110,648 | 0.61% | 0.51% |
| No signal word required | 123,722 | 0.7% | 2.9% |
Source: California Department of Pesticide Regulation, Pesticide Use Reports 2022 and 2023, site code 10, applications by product, joined to the product reference file supplied in the same year’s archive. Author calculation.
What it means. Nineteen in every twenty professional structural treatments in California used a product in the lowest labelled toxicity tier. DANGER products made up 0.61 percent of applications in 2022, and 91,524 of those 110,648 applications, 83 percent, were sulfuryl fluoride fumigations of tented, vacated buildings. Outside fumigation, DANGER-labelled products were about one application in 950.
What limits it. A signal word describes the acute, short-term toxicity of the product as sold. It says nothing about chronic effects, effects on wildlife or water, or how much reaches a person, which depends on how and where it is applied. A CAUTION product can still matter environmentally; our report on insecticides in US streams covers that. The 2022 to 2023 shift from CAUTION towards WARNING and no signal word partly reflects changes in the product reference file between years, which we did not trace product by product.
Restricted-use products
Some pesticides may be bought and used only by, or under the supervision of, certified applicators. A product can be restricted federally, by California, or both. The department’s restricted-products table records each product’s status.
| Restricted status | Share of applications, 2022 | Share, 2023 | Main active ingredients |
|---|---|---|---|
| Not restricted | 97.65% | 98.07% | |
| California restricted only | 1.63% | 1.32% | Difethialone, bromadiolone |
| Federal and California restricted | 0.53% | 0.46% | Sulfuryl fluoride |
| Federal restricted only | 0.19% | 0.15% | Some bifenthrin and diphacinone products |
| Any restriction | 2.35% | 1.93% |
Source: as above, joined to the department’s restricted-products table supplied in the 2023 archive, applied to both years. Author calculation.
What it means. About one application in 43 used a restricted product in 2022. The largest group is California-only restricted rodenticides, chiefly difethialone and bromadiolone, which are second-generation anticoagulants that California law has restricted since 2021 except in exempt settings. The second is the fumigant.
What limits it. The restricted-products table is the 2023 version, applied to 2022 as well; a product whose status changed between the years would be misclassified for 2022. Our explainer on restricted use pesticides sets out what the classifications mean for who may apply them.
What form the treatment takes
What it means. The largest single category is liquid concentrates, mixed with water and applied as sprays, at 28.7 percent. Solid bait forms are close behind: pellets, tablets and cakes at 15.6 percent and granules at 11.6 percent. Gels and pastes, the form used for cockroach and ant baiting, are 5.1 percent. Pressurized gas, which is fumigation, is 0.5 percent.
What limits it. The formulation is the product as sold, not the way it was applied. A granule can be broadcast or placed in a station. The category “Other (liquid)” at 10.6 percent is the department’s own catch-all.
One application in six is a rodenticide
Products containing a rodenticide active ingredient accounted for 3,017,398 applications in 2022, 16.5 percent of all structural applications, and 3,042,550 in 2023, 16.2 percent. Diphacinone appeared in 1,141,517 of them in 2022, bromethalin in 783,370 and cholecalciferol in 690,878.
What it means. Rodent baiting is a far larger part of professional pest control by count than by weight: our analysis of what structural pest control applies found diphacinone ranks fifth by applications and 83rd by pounds. Recurring bait-station servicing, where small amounts are replaced on every visit, is one plausible reason for the gap; the reports do not record visit type.
What limits it. We identified rodenticide products by their active ingredients rather than by the product file’s rodent flag, because that flag is also set on fumigant products labelled for rodents. Our report on rodenticides in California wildlife covers what reaches non-target animals.
Checks on the classification
1. Every application matched a product
Method. Joined each report’s product number to the same year’s product reference file.
Result. No unmatched applications in either year.
Limitations. A product’s label can change during its registration; the reference file holds one signal word per product.
2. Replication
Result. CAUTION products were 97.2 percent of applications in 2022 and 93.7 percent in 2023; DANGER products 0.61 and 0.51 percent; restricted products 2.35 and 1.93 percent. The direction of every finding repeats.
3. Fumigation accounted for separately
Method. Identified sulfuryl fluoride applications from its chemical code and compared them with the DANGER total.
Result. 91,524 of 110,648 DANGER applications in 2022 were sulfuryl fluoride.
Download the data
The tables in this report are published as CSV files under a Creative Commons Attribution 4.0 licence. You may republish, remix and build on them, including commercially, with attribution to The Pest Control Brief and a link to this page.
- Structural applications by signal word, restricted status, formulation and fumigant flag, 2022 and 2023 (CSV, 64 rows)
How to cite this report
The Pest Control Brief, “How Toxic Is Professional Pest Control? 18 Million California Treatments, Classified by Label”, 2 October 2026. https://thepestcontrolbrief.com/pest-control-pesticide-toxicity-labels/
References
- California Department of Pesticide Regulation. Pesticide Use Report annual archives for 2022 and 2023, including the product, formulation, product-chemical and restricted-products reference files. files.cdpr.ca.gov/pub/outgoing/pur_archives/. Accessed 2 October 2026.
- National Pesticide Information Center, Oregon State University. Signal Words fact sheet. npic.orst.edu/factsheets/signalwords.html. Accessed 2 October 2026. Source of the signal word definitions.
- California Legislature. AB 1788, California Ecosystems Protection Act of 2020, chaptered 29 September 2020. leginfo.legislature.ca.gov AB 1788. Accessed 2 October 2026.
How the classification was done
Scope. All 2022 and 2023 Pesticide Use Report records with site code 10, Structural Pest Control.
Unit. Applications from the application count field, counted once per report and attributed to the report’s product.
Joins. Product number to the product reference file for signal word, formulation, fumigant flag and rodent flag; to the restricted-products table for restricted status; to the product-chemical table for active ingredients.
Limitations. California only. Labels describe acute toxicity of the product as sold. Application counts are as reported by businesses; a fumigation and a bait-station check each count as one.
Last reviewed: 2 October 2026.
For reporters and consumer editors
Most quotable statistics
- 97.2 percent of 18.3 million professional structural pest control applications in California in 2022 used products labelled CAUTION, the lowest-toxicity signal word.
- 0.61 percent used DANGER-labelled products, and 83 percent of those were whole-building fumigations.
- 2.35 percent used a restricted-use product.
- One application in six, 16.5 percent, used a rodenticide.
- Liquid concentrates were the most common formulation, at 28.7 percent of applications.
Caveats that travel with them
Signal words measure acute toxicity of the product as sold, not chronic or environmental effects. California only.
Press summary
Nearly all professional pest control treatments in California use products in the lowest federal toxicity category, according to an analysis of state pesticide use reports by The Pest Control Brief. Of 18.3 million structural pest control applications in 2022, 97.2 percent used products labelled CAUTION. DANGER-labelled products accounted for 0.61 percent, mostly whole-building fumigation, and restricted-use products for 2.35 percent, led by rodenticides California has restricted since 2021. One application in six was a rodenticide. The analysis notes that label signal words describe short-term toxicity only and do not address environmental effects.
Headlines editors could use
- 97 percent of professional pest treatments use the lowest-toxicity label
- How toxic is your exterminator’s spray? 18 million treatments, classified
- One pest control visit in six is a rodent bait
- Restricted pesticides make up 2 percent of pest control in California
Common questions
Are professional pest control chemicals toxic?
Most are in the lowest labelled tier. 97.2 percent of California structural applications in 2022 used products labelled CAUTION, meaning slightly toxic by EPA’s acute toxicity categories.
What does the CAUTION signal word mean?
That the product as sold is slightly toxic if eaten, absorbed through the skin or inhaled, or causes slight eye or skin irritation. WARNING means moderately toxic and DANGER highly toxic or corrosive.
Which pest control treatments carry a DANGER label?
Mostly whole-building fumigation with sulfuryl fluoride, which was 83 percent of DANGER-labelled applications in 2022. Buildings are vacated and tented for fumigation.
Do exterminators use restricted pesticides?
Rarely by count. 2.35 percent of California structural applications in 2022 used a restricted product, mainly certain rodenticides and the fumigant.
Does a CAUTION label mean a product is safe for the environment?
No. The signal word covers short-term human toxicity only. Environmental effects are assessed separately.
How much professional pest control is rodent control?
About one application in six. Rodenticide products accounted for 16.5 percent of structural applications in 2022.
Is this the same outside California?
No other state publishes product-level structural use, so it cannot be measured elsewhere.
Where can I see the full breakdown?
Every category for both years is in the CSV above.
