Occupational exposure to pesticides has been linked to adverse cognitive and behavioral outcomes in agricultural workers (Ismail et al., 2012; Munoz-Quezada et al., 2016). Most of the literature to date has focused on organophosphate (OP) pesticides (Antonangeli et al., 2023; Fuhrimann et al., 2021b; Zuniga-Venegas et al., 2022) and has linked exposure to these insecticides to increased attention problems and impaired memory and motor function (Antonangeli et al., 2023; Cancino et al., 2023; Munoz-Quezada et al., 2016). Chronic OP pesticide exposure has also been associated with psychological distress symptoms such as irritability, anxiety, and depression (Beard et al., 2014; Farnham et al., 2021; Wesseling et al., 2010) even at low levels of exposure (Mackenzie Ross et al., 2010). A recent review of the literature on pyrethroid exposure and neurobehavioral outcomes among farmworkers found that exposure to these insecticides was associated with several adverse outcomes, including attention and motor coordination problems (Lucero and Munoz-Quezada, 2021). Additional research has also linked pyrethroid exposure to depression and anxiety symptoms in both occupationally and non-occupationally exposed populations (Furlong et al., 2020; Kori et al., 2018; Li et al., 2023). Nevertheless, little is known about how exposure to widely used fungicides and herbicides may impact neurobehavioral outcomes among workers (Fuhrimann et al., 2021a, 2022b; Weisskopf et al., 2013). Recently, our group found an association between exposure to the herbicide glyphosate, but not to insecticides or fungicides, and impaired visual memory among smallholder farmers in Uganda (Fuhrimann et al., 2022b). Weisskopf et al. (2013) found an increased hazard ratio for depression among agricultural users of herbicides but not among workers exposed to insecticides or fungicides.

Pesticide exposure is of particular importance in low- and middle-income countries (LMICs), where increased agricultural production and climate change has led to more frequent use of toxic pesticide ingredients (Zuniga-Venegas et al., 2022). Elevated exposure to pesticides in agricultural workers in LMICs is of concern due to lack or inadequate use of personal protection equipment (PPE), inappropriate hygienic practices during/after pesticide handling (Blanco-Munoz and Lacasana, 2011), and lack of pesticide regulations which has led to continued use of pesticides already banned in the United States (U.S.), Europe, and Canada (Bravo et al., 2011; Kesavachandran et al., 2009).

Mexico is the world's largest producer of avocados, accounting for approximately 45% of global production (Gordean, 2021). About 72% of Mexican avocados are grown in the state of Michoacán (Servicio de Información Agroalimentaria y Pesquera, 2023). In 2020, avocado production in Michoacán directly generated 310,000 jobs, with additional 78,000 being generated indirectly (Servicio de Información Agroalimentaria y Pesquera, S., 2022). It is estimated that every 1000 tons of harvested avocado generate approximately 160 jobs (Avocado Institute of Mexico, 2020).

However, to our knowledge, the health effects of pesticide exposure among avocado farmworkers have not been previously assessed. In this study, we aimed to assess exposure to multiple pesticides among avocado farmworkers in Michoacán and examine the association of exposure to these chemicals with cognitive outcomes and measures of psychological distress both individually and as a mixture.