Advocates express concern over pesticide levels in air surrounding schools in agriculture communities

On Oct. 14, the California Department of Pesticide Regulation (DPR) released its annual Air Monitoring Report declaring that no air samples taken at monitoring sites — all located on or near a school site — in 2023 detected pesticides at or above health-protective screening levels or regulatory targets.

On Oct. 22, the Environmental Working Group (EWG) released its own interpretation of CDPR’s data: Roughly four out of five air samples collected in the four most agriculture-intensive communities had detectable levels of pesticides.

According to advocates, similar to issues surrounding acceptable amounts of lead in drinking water, there really is no such thing as a “safe amount” of pesticides.

“There’s really no safe level of exposure, and we know that there is a tremendous amount of use,” explained Jane Sellen, co-director for Californians for Pesticide Reform.

Health risks from pesticide exposure are a concern not only for people working in fields where they are applied, but also for those living or working nearby, including children at schools close to agriculture. While pesticide-related health problems vary, Sellen noted that some of the chemicals used are linked to respiratory issues such as shortness of breath and asthma in the short term and can increase the risk of developing certain cancers in the long term.

According to the Centers for Disease Control and Prevention, asthma is linked to higher rates of student absenteeism — a risk factor for lower academic achievement and higher rates of dropping out of school. A 2019 study found that asthma contributed to between 14-18 percent of student absenteeism, even after accounting for other health and social risks.

“The reality is that people that teach in schools in farm working communities and people that live in these communities can attest to the enormous amount of suffering that’s experienced by children and families that honestly are least equipped to handle it,” she continued. “They might not have health insurance. They might lose their job if they don’t show up for work. These are also some of the most impoverished school districts in some cases, and they don’t have resources to meet the need.”

The four monitoring stations are Rio Mesa High School in Ventura County, Bonita Elementary School in Santa Barbara County, Ohlone Elementary School located on the border of Santa Cruz and Monterey counties and adjacent to Sequoia Elementary School in Kern County.

According to the DPR, “the 2023 data found that 95 percent of all samples analyses had no detectable pesticides. Twenty-one pesticides were not detected at all, and 11 were detected at very low, trace levels which indicates unlikely risk to or impact on people’s health.”

The EWG said that, “in total, the air monitoring samples detected 19 pesticides — almost half the total chemicals the CDPR tried to detect.”

The chemicals tested for are chosen based on their potential human health harms and possible high exposures in communities. According to DPR, the fumigants detected by the air monitoring stations — 1,3-dichloropropene, chloropicrin, methyl bromide and methyl isothiocyanate (MITC) — “are all restricted material pesticides, requiring applicator training and licensing, mandatory setbacks from buildings, the use of tarps to cover treated areas or other application methods with comparable levels of emission reduction, and other restrictions on use.”

While the samples taken “show pesticide levels below the state’s health-protective or regulatory targets … these levels might not align with the latest independent scientific research, which often shows health risks from toxic chemicals could occur at lower levels than what California regulators consider legal and safe,” according to EWG.

EWG’s analysis determined that five pesticides were found in more than one in five samples:

  • The herbicide pendimethalin was detected in 31.2 percent of samples
  • 1,3-dichloropropene was found in about a fifth of the samples
  • Chloropicrin was detected in 27.7 percent of samples
  • MITC and methyl bromide were found in about 30 percent of samples

New regulations restricting the use of 1,3-dichloropropene went into effect Jan. 1, 2024. They include requirements for larger setbacks from buildings, new tarp and soil application requirements, and additional restrictions to protect people who live near agricultural fields from potential exposure. Additional regulations to further restrict the use of 1,3-dichloropropene to add specific protections for people who work near an area where the pesticide was applied are also under development.