Pesticides and Chronic Diseases
William J. Rea, Kalpana D. Patel in Reversibility of Chronic Disease and Hypersensitivity, Volume 4, 2017
Pyrethroids are a widely used class of insecticides used for mosquito control and various insects in residential and agricultural settings. However, pyrethroids are highly neurotoxic and have been linked to cancer, endocrine disruption, suppression of the immune system, and various reproductive effects chemical sensitivity. This class of chemicals includes permethrin, bifenthrin, resmethrin, cyfluthrin, and scores of others. (Reference Read Beyond Pesticides factsheet Synthetic Pyrethroids.) Once the agency completes and approves the pyrethroid chemical assessment, it is likely that new uses of these pesticides will be added. The agency claims that more pyrethroid registrations may help combat recent pervasive pest problems, such as stink bugs and bed bugs, even though this class of chemicals is already known to be ineffective against these pests due to growing resistance issues compounded with continued pesticide use. However, serious issues such as the carcinogenic and endocrine-disrupting potential of several pyrethroids were not mentioned in the risk assessment even though a recent study published in Environmental Health Perspectives finds that low-dose, short-term exposure to esfenvalerate, a synthetic pyrethroid pesticide, delays the onset of puberty in at doses two times lower than EPAs stated no observable effect level.
Malaria
Roger Cooter, John Pickstone in Medicine in the Twentieth Century, 2020
The mosquito net has a long cultural and social history little explored by scholars. First used to reduce the nuisance of mosquitoes at night rather than to prevent malaria, bednets initially replaced ‘turtling,’ as it is called in Jamaica where today it is still practiced — sleeping with one’s head under the covers to avoid bites. Now associated with tropical elegance, they appear in films about Africa or India, wafting in the breeze of punkahs and suffused with colonial nostalgia. Since the 1980s, however, bednets have been increasingly suffused with insecticides. Ordinary nets, for all their elegance, do little to prevent malaria unless used under the strictest regime of tucking, folding and mending. Indeed, mosquitoes have often found them convenient perches from which to probe for an exposed hand or foot touching the net. Pyrethroids, which have low mammalian toxicity but are deadly to insects, prevent them from perching and sometimes drive them from the room altogether.
Agrochemicals: A Brief Overview
Dongyou Liu in Handbook of Foodborne Diseases, 2018
Natural pyrethrins from extracts of the flower Chrisanthenum cinerariaefolium have been used as insecticides for several centuries. Since pyrethrins decompose rapidly in the light, synthetic analogs, the pyrethroids, were developed (77). Pyrethroids have high insecticidal potency, moderately low mammalian toxicity, and lack of environmental persistence: these characteristics have assured their success, and these compounds now account for about 20% of the global insecticide market (78). Pyrethroids are used in agriculture and in the home setting, in medicine (e.g., for the topical treatment of head lice), and in soaked bed nets to prevent mosquito bites. Pyrethroids exert their insecticidal action by modifying the kinetics of voltage-sensitive sodium channels in the insect's CNS (78).
Metabolism of deltamethrin and cis- and trans-permethrin by rat and human liver microsomes, liver cytosol and plasma preparations
Published in Xenobiotica, 2019
Laura Hedges, Susan Brown, Audrey Vardy, Edward Doyle, Miyoung Yoon, Thomas G. Osimitz, Brian G. Lake
Pyrethroids are a class of synthetic insecticides that are derived from the structures of the six active insecticide components (Pyrethrins I and II) of Pyrethrum extract, which is obtained from the dried and ground flowers of Chrysanthemum cinerariaefolium (Bhat, 1995; Elliott, 1995). Like natural pyrethrins, synthetic pyrethroids modulate nerve axon sodium channels in insects, resulting in neurotoxic effects (Gammon et al., 2012; Soderlund et al., 2002; Soderlund, 2012). Although synthetic pyrethroids exhibit a low oral toxicity to mammals, they have been shown to produce neurotoxic effects, with toxicity being considered to be due to the parent pyrethroid and not to any subsequent metabolites (Lawrence & Casida, 1982; Rickard & Brodie, 1985; Soderlund et al., 2002; Tsuji et al., 2012). Potency for producing acute neurotoxicity varies between different pyrethroids, with deltamethrin (DLM) being more potent than permethrin (Tsuji et al., 2012).
Hemoptysis after exposure to a household insecticide spray: A case report and review of the literature
Published in Canadian Journal of Respiratory, Critical Care, and Sleep Medicine, 2019
A. J. Ruberto, H. D. Morakis, C. L. D’Arsigny
Pyrethroids, insecticides derived from chrysanthemum flowers and pyrethrins, a synthetic insecticide, share a similar chemical structure and mechanism of action.2 This case demonstrates findings that are characteristic of respiratory distress secondary to chemical pneumonitis after exposure to an aerosolized pyrethroid or pyrethrin.3–10 Although such case reports are infrequent and usually result in isolated respiratory irritation, the patient’s underlying COPD and active anticoagulation likely increased her risk of more serious adverse respiratory events.1,11 The lack of ventilation in the apartment after the windows were closed may also have contributed to the increased risk of developing respiratory symptoms.3
The progressive alteration of urine metabolomic profiles of rats following long-term and low-dose exposure to permethrin
Published in Biomarkers, 2020
Yu-Jie Liang, Pan Wang, Ding-Xin Long, Hui-Ping Wang, Ying-Jian Sun, Yi-Jun Wu
Pyrethroid insecticides are extensively used in agriculture and public health to control pest insects because of their selective toxicity for insects and relatively low acute toxicity to mammals (Casida and Quistad 1998, Prasanthi and Rajini 2005). However, recent studies show that the insecticides are not completely harmless to human health (Nicolopoulou-Stamati et al. 2016, Chrustek et al. 2018). Permethrin, one of the pyrethroid insecticides, is mainly used for household pest control and malaria eradication (Lawrence and Casida 1983, Soderlund et al. 2002, Bradberry et al. 2005). It can cause a distinct, albeit temporary decrease in the activity of voltage-gated sodium channels in nervous system (Lawrence and Casida 1982, Michelangeli 1990, Vais et al. 2001, DeMicco et al. 2010). Its wide application makes it an increasing risk for human health (Morgan et al. 2007).