Pesticide incidents in the San Joaquin Valley

A pesticide helicopter, similar to the ones used by the Alpine Helicopter Service Inc. which were involved in the pesticide drift incidents

From 1975 to 1996 McFarland California reported 21 of its children as being diagnosed with cancer which is “3 times” higher than normal considering the fact that McFarland had a population of around 8000 at the beginning of the Cancer Cluster.[10] As the reports of cancer cases began to increase locals pointed fingers at the pesticides which were commonly being used on farms in the area and soon after new outlets such as the LA Times began to take notice and started reporting on the incident.[11] Because of the severity of the cluster and the amount of attention the cancer cluster was receiving, the U.S. Department of Health and Human Services (USDHHS) launched an investigation on the incident. The USDHHS performed a multitude of tests on households, surroundings areas, the air, and waterways but found nothing conclusive that could point at pesticides as being the cause of all the cancer incidents.[12] Pesticide companies were quick to defend themselves after the report came out because as the report stated there was no indication that pesticides were at fault. This event remains controversial and many are still divided on whether or not pesticides played a bigger role that may have gone unnoticed despite the investigation by the USDHHS.

Alpine Helicopter Service is a Lodi CA based company that sprays pesticides over large farm areas. From 2013 to 2020 Alpine had been directly involved in causing a multitude of pesticide drift incidents that ended up endangering the health of people in the area and created crop loss for nearby farms that the pesticides ended up damaging.[13] In an especially controversial incident, a pesticide drift occurred while children were playing soccer at the Stockton Sports Complex (September 7, 2019) which put the health of the children and their families in danger.[14] Many news outlets such as Capitol Weekly and The Record began reporting and identifying at least 11 separate pesticide drift incidents that Alpine was involved in.[15] From a woman begin sprayed as the pesticide sprayer passed overhead to pesticide drift occurring over a schoolyard.[14] As a result, in 2020 the California Department of Pesticide Regulation (DPR) and California's attorney general Xavier Becerra filed a lawsuit against the company which is still currently being investigated and processed.[13] This incident is one of many pesticide drift incidents that has been recorded which are all being investigated by the DPR and reported on by various outlets.[15]

During the early 1960's and late 1970's, doctors and medical professionals from across the country conducted research in the Central Valley to better understand the effects of pesticides on the human body as well attempt to combat further incidents.[16][17] A majority of this research was conducted on field workers who sought out medical attention for poisonings, since they had the most exposure to such pesticides than any other group of people.[18]

Many doctors conducted their research on organophosphate pesticides, one of many forms of pesticide that specifically targets the Acetylcholinesterase enzyme. The intention of this research was to differentiate pesticide poisonings from other common diagnoses at the time, as well as further understand how what specific chemicals were harming the human body. Some of the most common insecticides that were causing poisonings were found to be Parathion, Phosdrin, Thimet, and Systox. A large factor in this reason this research was conducted was due to the fact that it was difficult for doctors to diagnose a pesticide poisoning during this time. The symptoms of pesticide poisoning were to difficult to distinguish from other much more common diagnoses at the time. Due to the work and dedication of these doctors, pesticide incidents have been well documented and are distinguishable when diagnosed.

Research published in Environmental Toxicology and Chemistry has shown that pesticides enter the atmosphere through various methods. There were pesticide residues from the Central Valley found as far away as the Arctic.[19] Pesticide residues spread through water surfaces, wet deposition, and through the air mass. Although individual pesticide levels are below acute toxicity levels in the Central Valley, there are synergestic and additive effects of many pesticides that harm many sensitive species.[19]

A more detailed study has been done in 2004 regarding the toxicity of pyrethroid in specific environments. Data collection showed that cumulative effects of various pyrethroids were responsible for 17 out of 23 samples used to measure toxicity.[20] The most extreme cases were found in Tailwater ponds. There were 77 sedimentary samples used for data collection, and 42% of the samples had toxic levels of pesticides that caused the mortality of species of several Amphipods.[20] Furthermore, data suggested that pyrethroid concentrations in the Central Valley were greater after their usage in agriculture compared to concentrations after heavy rains.[20] This suggests that pesticide levels during irrigation season in places with greatest pesticide usage - Fresno, Madera, Stainslaus, Sutter - would be particularly detrimental to residents and various species in the environment.

Studies show that pesticide usage is not only limited to agricultural settings.

Recently, the California Department of Pesticide Regulation proposed rules to restrict neonicotinoid chemicals, insecticides that harm bees that pollinate crops.[21] Also, in 2024, all neonicotinoid in non-agricultural settings would be banned. This chemical is used throughout all the states for agriculture, but it is especially concentrated in the Central Valley. Fresno, Kern, Tulare, Monterey and San Joaquin are among the top counties of neonicotinoid usage.[21] Now, the next step for environmentalists is to advocate for politicians to address crop seeds that are coated with neonicotinoids. Environmentalists have proved that these coated seeds still contribute significantly to the neonicotinoid mass, and that it is detrimental to honeybees.

The United Farm Workers have fought to improve farmworkers' working conditions,[22] and have added pressure to politicians through their union marches. President Biden supported this by releasing Assembly Bill 2183, affirming that farmworkers have the fundamental right to gather and advocate for themselves regarding their workplace. Gavin Newsom followed up and enacted the law in California.[23] Both Gavin Newsom and President Biden agreed that farmworkers should have an easy way to form a union. With support from politicians, the Union worked to push through bills that regulate whether or not the farmworkers can work in the heat.[23]

Following the McFarland Cancer Cluster in 1975, the small city in California never fully recovered from the effects of the pesticides. This is a city inhabited mostly by farmworkers, and 94% of the population is Latino.[24] City leaders believed that the poor economy of the city was to blame for the Cancer Cluster. The majority of the residents wanted federal officials to leave the town. Even a decade or so after the incident, there were about 1 in 100 cases of cancer concentrated in this small community. Investigators started collecting data but nothing conclusive was found. This inability to find a clear conclusion enraged the civilians.[24] For instance, some people in the McFarland community complained that the investigations were incomplete. One resident reported that there were no investigations of the deep soil or the air. A few others did not believe that the clusters even existed.[24]

A more recent experience came from the Madera community.[25] One problem was that the orchards were planted just outside of residential neighborhoods, and the chemical spray often missed the leaves and ended up on people's homes. One resident in the community reported that the noises of the machines and the dirt from the pesticide spray created a huge disturbance in the daily life in the neighborhood.[25] In the town of La Vina, over 300 residents tried to leverage a new state policy to decrease the pesticide drift from the fields into the community. They reported to the state officials that the orchards were too close to the residential area, and that the pesticides resulted increased the chance of premature death.[25] These residents have partnered up with local land and water agencies to allocate state funds to shut down farmlands. The La Vina residents also pointed out the effects of the carcinogenic compounds near their elementary schools. They have requested the United States Environmental Protection Agency to give them a $500,000 grant to perform chemical tests for safety measures.