The California People and Pesticides Explorer is a one-of-a-kind tool that makes it easier to view, map, and download California’s pesticide use data, and serves as a resource for scientists, growers, advocates, and the general public. This interactive tool allows users to view pesticide use data alongside demographic data in a variety of census geographies including townships, zip codes, and counties.
This tool is an important new feature on PAN’s Pesticide Info web tool. You may access the new California People and Pesticides Explorer by taking the option under “Pesticide Maps” on the main menu of the Pesticide Info site or you can go directly to the tool here.
This PAN resource provides a scenario walk-through that can help you to become familiar with the new tool. You may opt to view the webinar recording here and follow the tutorial (beginning at 16:00 on the recording), or you may scroll down and walk through the step-by-step instructions provided below.
Scenario tutorial
Lettuce is an extremely important vegetable product in the United States, accounting for nearly one-fifth of the cash receipts for vegetables and melons. In 2022, 85% of the lettuce produced in the US was consumed in-country and 70% of all lettuce produced in the US came from California.
When you first visit the mapping tool, the page should look similar to what is shown below.
Certain data fields will be set to default values.
- The data range will initially be set to Jan 1, 2022 to Dec 31, 2022
- The Pesticide Application will be set at Agricultural use.
- The Geography divisions will be set to Townships
Each Township represents six square miles and each township is segmented into 36 Sections. Each Section is one square mile (640 acres). Townships are used for surveying purposes throughout the US. The Township Geography maps typically give the most representative maps for showing the intensity of spray applications in the area. However, other Geographical breakdowns might be more useful for other purposes.
- Change Geography to County
- Move the mouse over different counties to view county-specific data
The mouse over function allows you to view general details for every Geography selection.
- Change Geography to Sections
You will see a map that shows no detail as shown below:
Sections and Tracts are smaller land areas and you will need to zoom in to see results. Please note the blue box that says “Zoom in to view data.”
- Zoom in by clicking on the plus sign at top left or using the scroll button on your mouse
- Zoom back out to see the whole map
- Change Geography to Townships
- Go to Crop Type and select both Head Lettuce and Leaf Lettuce
Notice the total pesticides (active ingredient) applied to these crops is included in the pull down as you select them. Total pesticides applied to these crops in California for one year is about 2 million pounds.
- Go to Application Method and select ALL
- Change the Application Method to Aerial and view the map
- Change the Application Method to Fumigant and view the map.
- Change the Application Method to Ground and view the map.
The majority of pesticide use on lettuce in California uses ground application methods. Smaller amounts of pesticide ingredients are applied using fumigation or aerial application. While all applications of pesticides have the potential to drift from the target crop, aerial and fumigant applications are much more susceptible than ground applications.
- Change the Application Method to ALL for the rest of this scenario.
- Go to the Risk and Impact section
- Select Carcinogen
The map will not change significantly. Many pesticides applied to lettuce in California have been identified as known carcinogens.
If you look under the map, you will see several buttons.
The excel and CSV data download options allow you to access the raw data that is used to generate these maps. If we download the data at this point, we can perform our own calculations and learn that 867,504 pounds of the 2 million total are identified as carcinogens.
While the tutorial does not walk you through the process, you should also note that you have the ability to save and reload maps for later access.
- Click on the View Data Table option
We can also view the raw data without downloading an excel or CSV file. We can make columns wider by sliding the bars between the data labels in the top row. The data labels themselves are abbreviations. The excel and CSV files include full descriptions of each. You may also view the information provided when you select the About button just above the map.
The second column show pounds of active ingredient applied and the third column shows total pounds of product (including any adjuvants) applied.
- Click on the X at the top right of the data table to close it
- Go to Risk and Impact Section and select Reproductive Toxin
At this point, all pesticides applied that were identified as either a carcinogen or a reproductive toxin will be included in the map.
- Deselect Carcinogen
Now only data for pesticides that are reproductive toxins will be shown on the map.
- Unselect Reproductive Toxin
- Select Groundwater Contaminant
This is an example that shows us how the tool displays no application of pesticides that meet the criteria entered to create the map. There are currently no reported pesticides used on lettuce in California that have been identified as groundwater contaminants.
- Remove Groundwater Contaminant
- Go to Chemical and Product Information
- Go to Pesticide Class and select Organophosphates
About a fifth of the chemicals used on lettuces are Organophosphates.
Organophosphates are known for the effect on the nervous system. Acute (short term) poisoning symptoms include confusion, seizures and respiratory illness. Chronic (long term) harms include neurological disorders and harm to the development of children.
- Deselect Organophosphates
- Go to Active Ingredient
- Type in “Bensulide” as the Active Ingredient and view the map
About 320,000 lbs of this product was applied to lettuce crops in California in 2022. It is one of the most common herbicides used in lettuce.
- Go to Risk and Impact Section and select Carcinogen
There will be no date showing the use of Bensulide because it has not been identified as a carcinogen.
- Deselect Carcinogen
- Select Cholinesterase Inhibitor (Colon-ester-ase Inhibitor)
Bensulide is an organophosphate and all pesticides in this class are Cholinesterase inhibitors. Nervous system ailments are all possible through exposure to the skin, by breathing it in or swallowing it.
- Choose the Use Over Time button above the map
There were two peak use periods for Bensulide on lettuce crops in California in 2022. There is a primary peak application period in July and August and a secondary peak in October.
- Change the Date Range to start at January 2017 and end December 2022.
The similar curve shape for each year illustrates that this is a common pesticide use pattern for lettuce in California. We can expect the heaviest uses in July, August and October.
- Select the Demographic Comparison button that is located above the map.
The map screen will now be divided to show two maps. The map on the left provides the pesticide application data and the right-most map depicts demographic data.
Data for both pesticide use rates and population are displayed as you place the mouse over each Township. You should notice that there are some larger populations in Townships that also have high application rates of bensulide. Take time to explore the use of these side by side maps. If you would like to see more, please view the webinar to see the tool in action.
