Conventional agrochemicals towards nano-biopesticides: an overview on recent advances

Pesticides are classified into several groups based on their structure, including fungicides, insecticides, herbicides, bactericides, and rodenticides. Pesticides are toxic to both humans and pests. For pest control, a very small amount of pesticides reach their target pests. Therefore, nearly all pesticides move through the environment and exert adverse effects on beneficial biota and public health. These chemicals pollute the water, soil, and atmosphere of the ecosystem. Agricultural workers in greenhouses and open fields, exterminators of house pests, and workers in the pesticide industry are occupationally exposed to pesticides. Pesticide exposure in the general population primarily happens through the consumption of food and water contaminated with pesticide residues; however, substantial exposure can also occur outside or inside the house. Currently, intelligent, responsive, biodegradable, and biocompatible materials have attracted considerable interest for the formulation of green, safe, and efficient pesticides. It was indicated that utilizing nanotechnology to design and prepare targeted pesticides with an environmentally responsive controlled release via chemical modifications and compounds offers great potential for creating new formulations. Furthermore, biopesticides include microbial pesticides, which are naturally happening biochemical pesticides. In addition, pesticidal substances generated by plants with added genetic materials, i.e., plant-incorporated protectants (PIPs), have emerged. Based on the foregoing evidence, various types of pesticides are summarized in this review for the first time. Here, new pesticides including nano-pesticides and biopesticides are discussed while focusing on the most recent findings on targeted and safe nano-formulated biopesticides and nano-pesticides. Graphical Abstract

Factors Associated with Levels of Organophosphate Pesticides in Household Dust in Agricultural Communities

Organophosphate (OP) pesticides are associated with numerous adverse health outcomes. Pesticide use data are available for California from the Pesticide Use Report (PUR), but household- and individual-level exposure factors have not been fully characterized to support its refinement as an exposure assessment tool. Unique exposure pathways, such as proximity to agricultural operations and direct occupational contact, further complicate pesticide exposure assessment among agricultural communities. We sought to identify influencing factors of pesticide exposure to support future exposure assessment and epidemiological studies. Household dust samples were collected from 28 homes in four California agricultural communities during January and June 2019 and were analyzed for the presence of OPs. Factors influencing household OPs were identified by a data-driven model via best subsets regression. Key factors that impacted dust OP levels included household cooling strategies, secondary occupational exposure to pesticides, and geographic location by community. Although PUR data demonstrate seasonal trends in pesticide application, this study did not identify season as an important factor, suggesting OP persistence in the home. These results will help refine pesticide exposure assessment for future studies and highlight important gaps in the literature, such as our understanding of pesticide degradation in an indoor environment.

Pesticide toxicity assessment and geographic information system (GIS) application in small-scale rice farming operations, Thailand

The objectives of the study were to evaluate the impact of pesticide exposure on farmer health during non-active rice farming and active rice farming periods and present the change in the individual cholinesterase activities (%reduction) on the geographic information system (GIS) mapping in Nakhon Ratchasima Province, Thailand. Acetyl- and butyryl-cholinesterase (AChE and BuChE) activities were monitored during both study periods using Test-mate ChE (Model 400). The location of paddy fields was specified using Garmin geographic positioning system MAP 62s. Fifty-eight farmers who participated in this study had an average age of 49.2 ± 6.9 years. Higher prevalence of all health symptoms was observed among farmer participants during the active rice farming period comparing to the non-active rice farming period (p < 0.01). Furthermore, farmers had significantly lower activities of AChE and BuChE during the active rice farming period comparing to the non-active rice farming period (p < 0.01). Our findings indicate that the GIS mapping indicate that the cases with a significant enzyme inhibition have dispersed across the agricultural and the nearby residential areas. This, investigation can be used to promote safer use of pesticides among farmers and mitigate pesticide exposure among residents living in close proximity to a rice field.

Evidence on Human Exposure to Pesticides and the Occurrence of Health Hazards in the Brazilian Population: A Systematic Review

Brazil is among the biggest pesticide consumers in the world, with its population severely exposed to tons of such substances, both because of environmental contamination and occupational use. The health consequences of pesticide exposure are well-documented, but still sparse regarding Brazilian population. This study systematically reviewed the Brazilian studies published that address the relationship between exposure to pesticides and health problems in the Brazilian population. Also, information about pesticide use in Brazil is provided. The included studies showed that exposure to pesticides has a relevant impact on the health of the Brazilian population, regardless of age and gender, and on workers in rural areas or not. Most poisoning events seem to result from the continuous use of pesticides, whether occupationally or environmentally, characterizing a public health problem. The major consequences reported in literature were damage to the central nervous system, cancer, deleterious effects on rural workers' health, intoxications, malformations, and endocrine changes. These findings point out the need to understand the impact of chronic exposure to pesticides on severely exposed people and highlight the importance of creating public policies to protect them and avoid disease occurrence.

Parenting, Pesticides and Adolescent Psychological Adjustment: A Brief Report

Pesticides used to control insects, such as pyrethroids, are neurotoxicants, yet adolescent researchers often overlook their potential role in adolescent psychological adjustment. This brief report is guided by bioecological theory and considers the possible independent and interactive effects of environmental pyrethroid pesticide exposure for adolescent depressive symptoms. Self-reported adolescent appraisals of the parent–child relationship and depressive symptoms were obtained from a convenience sample of impoverished, predominantly Latino urban youth (n = 44). Exposure to environmental pyrethroids was obtained from wipe samples using a standardized protocol. Parent–adolescent conflict was higher in households with bifenthrin than those without, and adolescent depressive symptoms were elevated in homes where cypermethrin was detected. In addition, the presence of bifenthrin in the home attenuated the protective effects of parental involvement on adolescent depressive symptoms. The current results suggest that adolescent mental health researchers must consider the synergistic combinations of adolescents’ environments’ physical and social features. Given the endemic presence of pesticides and their neurotoxic function, pesticide exposure may demand specific attention.

Pesticide Exposure Risks to Chiropteran Species and the Impacts on Emerging Zoonotic Diseases

Neonicotinoids have been in the spotlight in the pollinator community as they persist in the soil, have high water solubility, and have been associated with negative health implications on insect pollinators. The risk of new novel pesticides, including neonicotinoids, to bats are largely unknown. Bats have unique physiology as they are the only mammals capable of true and sustained flight, and have physiological adaptations including echolocation and torpor which under current protocols for acute and chronic toxicity studies in birds and terrestrial animals are not assessed. Due to these characteristics, some have argued that bats may serve as important bioindicators for ecosystem health and pesticide use. This chapter will focus on pesticides, and discuss the increased risk of exposure, morbidity, and mortality of bats species due to their unique physiology and natural life history. Special emphasis will be on potential increased risk of zoonotic disease transmission in bats exposed to emerging contaminants that suppress their immune system or cause increased biological stress.

Pesticides as an Occupational Hazard Facts and Figures

The chapter gives insight into the harmful use of pesticides in different professional environments. It portrays the use of pesticides as the potential risks to the health of users and third parties and a danger to the environment. The use of pesticides has increased at a phenomenal rate. Pesticides and their threat to the biological world have reached almost hysterical proportions. Their residues are found everywhere, particularly those of the so-called “hard pesticides” or organochlorine compounds, DDT. Herein, an attempt has been made to reflect pesticide exposure in different occupational settings and their harmful effects on humans. Excess use of pesticide in agriculture has placed workers in this industry at risk of lethal exposure. Personnel working in domestic pest control service is also from continuous exposure to the pesticide. Further, the chapter highlights various corrective measures to be taken by the people working in different occupational settings to combat the dangerous effects of pesticides in everyday life.

Environmental exposures contribute to respiratory and allergic symptoms among women living in the banana growing regions of Costa Rica

ObjectivesThis research evaluates whether environmental exposures (pesticides and smoke) influence respiratory and allergic outcomes in women living in a tropical, agricultural environment.MethodsWe used data from 266 mothers from the Infants’ Environmental Health cohort study in Costa Rica. We evaluated environmental exposures in women by measuring seven pesticide and two polycyclic aromatic hydrocarbons metabolites in urine samples. We defined ‘high exposure’ as having a metabolite value in the top 75th percentile. We collected survey data on respiratory and allergic outcomes in mothers as well as on pesticides and other environmental exposures. Using logistic regression models adjusted for obesity, we assessed the associations of pesticide exposure with multiple outcomes (wheeze, doctor-diagnosed asthma, high (≥2) asthma score based on symptoms, rhinitis, eczema and itchy rash).ResultsCurrent pesticide use in the home was positively associated with diagnosed asthma (OR=1.99 (95% CI=1.05 to 3.87)). High urinary levels of 5-hydroxythiabendazole (thiabendazole metabolite) and living in a neighbourhood with frequent smoke from waste burning were associated with a high asthma score (OR=1.84 (95%CI=1.05 to 3.25) and OR=2.31 (95%CI=1.11 to 5.16), respectively). Women who worked in agriculture had a significantly lower prevalence of rhinitis (0.19 (0.01 to 0.93)), but were more likely to report eczema (OR=2.54 (95%CI=1.33 to 4.89)) and an itchy rash (OR=3.17 (95%CI=1.24 to 7.73)).ConclusionsWhile limited by sample size, these findings suggest that environmental exposure to both pesticides and smoke may impact respiratory and skin-related allergic outcomes in women.