Posts Tagged: pesticides
Last month, a California grape farmer was fined $10,000 for using a pesticide in violation of the label, then packing and attempting to sell the tainted fruit. DPR detected the residues of a pesticide on the produced that was not registered for use on grapes.
Cases like this are rare in California but remind growers how important it is to apply pesticides correctly by following all pesticide label directions. The California Department of Pesticide Regulation (DPR) runs the most extensive Pesticide Residue Monitoring Program in the nation and is hard at work ensuring that the fruit and vegetables we purchase and consume are free from illegal pesticide residues.
Understanding and following label instructions is the focus of a new online course developed by the University of California Agriculture and Natural Resources Statewide Integrated Pest Management Program (UC IPM).
The program, Proper Pesticide Use to Avoid Illegal Residues, is targeted to those who apply pesticides or make pesticide recommendations. It explains what pesticide residues are, how they are monitored, and highlights important residue-related information from several sections of pesticide labels. In addition, the course identifies the following as the most important factors leading to illegal residues:
- Using a pesticide on a crop for which it is not registered
- Applying pesticides at an incorrect rate
- Ignoring preharvest intervals, re-treatment intervals, or plantback restrictions
Course participants are presented with several real-life scenarios. They must search through actual pesticide labels to determine if the scenario illustrates proper use of pesticides or if the described situation could potentially lead to illegal residues.
The overall goal of this course is to have participants follow pesticide label instructions when they return to the field. Following the label can eliminate incidences of illegal pesticide use.
Proper Pesticide Use to Avoid Illegal Residues is published just in time for pest control advisers and pesticide applicators who are still a few units short to renew their licenses or certificates with DPR. The course has been approved for two hours of Pesticide Laws and Regulations continuing education units (CEUs) from DPR and costs $40. If you don't need CEUs, but are still interested in viewing the course content, check it out for free on YouTube.
DPR recommends that renewal packets be submitted before Nov. 1 in order to receive your renewed license or certificate by Dec. 31, as the processing time can take up to 60 days. For additional online courses that UC IPM offers, visit the online training page.
As consumers, we put a lot of care into the food we buy. We tend to trust that the produce we purchase at the local grocery store is free of pesticides and safe to eat.
Traces of pesticide residue are normal and even expected after pesticides are applied to food crops, but by the time produce is ready to be sold, purchased, and consumed, residues are usually far below the legal limit.
In its latest report from 2013, the California Department of Pesticide Regulation (DPR) reported that there was little or no detectable pesticide residue in 97.8 percent of all California-grown produce. This demonstrates a strong pesticide regulation program and pesticide applicators that apply pesticides safely and legally. However, there have been instances in California where a pesticide not registered for a specific crop has been used unintentionally, resulting in illegal residues and eventually crop loss and destruction.
The Environmental Protection Agency sets tolerances for the maximum amount of pesticide residue that can legally be allowed to remain on or in food.
DPR regularly monitors domestic and imported produce for pesticide residues and is considered the most extensive state residue-monitoring program in the nation.
The primary way pesticide applicators can assure that they make proper applications and avoid illegal pesticide residues is to follow the pesticide label. The UC Agriculture and Natural Resources Statewide Integrated Pest Management Program (UC IPM) put together a 26-page card set in English and Spanish on understanding pesticide labels. Although intended primarily for pesticide handlers, applicators, safety trainers, and pest control advisers, these cards can be useful for anyone who applies pesticides in urban or agricultural settings. The cards explain when to read the label, describe what kind of information can be found in each section of a pesticide label, and point out specific instruction areas that will help applicators apply pesticides safely and avoid illegal pesticide residues.
To download copies of the card set in English or in Spanish, see the UC IPM web site.
Author: Cheryl Reynolds
Pesticides that have not been sold at the retail level for years are still regularly found in residential runoff water, according to research in Sacramento and Orange counties by UC scientists. So called “legacy pesticides” are probably old products that homeowners still have on their garage shelves and are still using to control pests.
An earlier study by the California Department of Pesticide Regulation and the UC Integrated Pest Management Program found that 60 percent of pesticides sold to consumers are for ant control. For that reason, UC Cooperative Extension specialist in landscape horticulture Loren Oki of UC Davis and UC Cooperative Extension water resources/water quality advisor Darren Haver focused on ant control pesticides in their residential runoff research project. The scientists collected 830 water samples from the storm drains in four Sacramento County neighborhoods and four Orange County neighborhoods between 2006 and 2010.
“In Sacramento County, we trained a team of about 25 volunteer UC Master Gardeners to collect the samples,” Oki said. Orange County samples were collected by Haver and his staff. All the samples were sent to UC Riverside for analysis.
“Pesticides that have been off the market since 2004 are still found in the water,” Oki said. “We found organophosphates – diazinon and chlorpyrifos – in differing amounts, typically more in Orange County than Sacramento County. We also found a fairly new pesticide, fipronil, in most of our water samples.”
The scientists also noted random spikes in the amount pesticides in runoff water, unconnected with storms or other conditions, which suggested that they were directly associated with particular pesticide applications in the neighborhoods.
There are several ways homeowners can help prevent contamination of the California water supply. For one, dispose of old pesticides properly. Most cities and counties have programs for disposal of household hazardous waste.
When using pesticides, Oki suggests residents carefully read the label and use common sense.
“Don’t put pesticides on impervious surfaces, like concrete walkways and driveways,” he said. “Don’t put pesticides in garden areas where runoff might be generated. That runoff will carry the pesticides with it.”
Residents can also minimize the amount of water runoff from the property. Oki suggests reducing irrigation and targeting the water application properly. In addition, promote soil infiltration by promoting soil health.
“If you don’t generate runoff, you won’t have pesticides running off too,” Oki said.
Residential runoff can convey pesticides into water supplies.
Technology that allows orchard sprayers to skip the space between trees can protect the environment while saving growers money.
The idea is simple: when orchards receive dormant and in-season sprays of agricultural chemicals, the spray should only fall on the trees where it is needed, rather than on the ground, where it is not.
Orchard sprayers can be retrofit with target sensors that activate spray nozzles only when a tree is present.
“By reducing the application rate of the pesticide mix, each tank load of material covers a greater land area, effectively reducing the number or refills, ferry trips and time spent spraying each orchard,” wrote author Durham Giles, UC Davis professor of biological and agricultural engineering, in California Agriculture. “This provides additional economic return to growers by reducing labor and fuel costs.”
Based on field tests, the authors estimated that reductions in pesticide and operating costs with smart-sprayer technology ranged from $58 per acre for peaches grown in the San Joaquin Valley to $31 per acre for prunes grown in the Sacramento Valley.
At the same time, reductions in the total amounts of pesticide sprayed ranged from 15 percent for a mature prune orchard near Chico, to 22 percent for a mature almond orchard near Modesto, to 40 percent for a younger (more open) prune orchard near Oroville.
The trees themselves received the same amount of pesticide in the smart-sprayed orchards, but a lot less pesticide ended up on the ground than in the control. “For the almond and more open prune orchards, the reductions were 79 percent and 59 percent, respectively,” Giles and colleagues wrote.
Likewise, when the amount of pesticide in water running off from the younger prune orchard was measured, the reduction was 54% in the smart-sprayed orchard compared to the control.
Despite its obvious benefits, the study authors noted that “use of the smart-spray technology is growing but remains a small part of the spraying equipment market.” The retrofit spray sensor and control equipment cost about $15,000, with an estimated payback period of 2 years or less, given documented cost reductions.
Furthermore, the U.S. Department of Agriculture’s Environmental Quality Incentives Program (EQIP) can provide up to $30 per acre for a total of $15,000 per contract when the new equipment provides a 20% reduction in spray, which as been documented in peer-reviewed research such as the California Agriculture article.
“The amount is sufficient to adequately cover the cost of purchasing a typical target-sensing system for an orchard sprayer,” the authors note in California Agriculture journal.