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Occupational Neurotoxic Diseases in Developing Countries
Published in Lucio G. Costa, Luigi Manzo, Occupatinal Neurotoxicology, 2020
With good work practice and safety precautions, pyrethroids are unlikely to present acute toxicity for those occupationally exposed. However, cases of acute occupational pyrethroid poisoning were first reported in China in 1982, due to inappropriate handling, spraying with higher concentration than that recommended on the label, longer exposure duration, spraying against the wind, clearing blocked nozzles by mouth and hands, poor personal hygiene and lack of personal protection. During 1983–1988, there were 573 cases of acute pyrethroids poisoning reported in the Chinese medical literature.26 Occupational pyrethroid poisoning accounted for one third of the total patients, and two third were of oral poisoning. The majority of cases resulted from exposure to deltamethrin, followed by fenvalerate, cyper-methrin and other pyrethroids (cyfluthrin, fenpropathrin).26 In an epidemiological survey of occupational poisoning in China, the prevalence of mild acute pyrethroid intoxication in 3113 spraymen was 0.38%.27
Pesticides
Published in José L. Tadeo, Analysis of Pesticides in Food and Environmental Samples, 2019
José L. Tadeo, Beatriz Albero, Rosa Ana Pérez
Pyrethrins are natural insecticides obtained from pyrethrum, extracted from the flowers of certain species of chrysanthemum. The insecticide properties are due to five esters that are present mostly in the flowers. These esters have asymmetric carbon atoms and double bonds in both alcohol and acid moieties. The naturally occurring forms are esters from (+)-trans acids and (+)-cis alcohols. Synthetic pyrethrins, called pyrethroids, present better activity for a larger spectrum of pests than natural ones. They show selective activity against insects and present low toxicity to mammals and birds. Pyrethroids are considered as contact poisons, affecting the insect nervous system and depolarizing the neuronal membranes. These compounds are degraded in soil and have no detectable effects on soil microflora. They have also been used in the household to control flies and mosquitoes. Piperonyl butoxide (C19H30O5) is used as a synergist for pyrethrins and related insecticides (Table 1.19).
The Chemical Technology of Wool Finishing
Published in Menachem Lewin, Stephen B. Sello, Handbook of Fiber Science and Technology: Chemical Processing of Fibers and Fabrics, 2018
Trevor Shaw, Max A. White, L. Benisek, M. A. Rushforth, J. R. Christoe, I. M. Russell
The synthetic pyrethroids are a series of insecticides whose molecular structure is related to the pyrethrins, natural insecticides found in the flower-heads of the daisylike pyrethrum plant, Chrysanthemum cinerariaefolium. This plant is cultivated in certain areas of the world, notably Kenya, and the pyrethrins extracted for commercial use. Pyrethrin I, the most important of the six recognized insecticidal components of pyrethrum extracts, is shown in Fig. 5.36, formula X. The natural pyrethrins are characterized by their low mammalian toxicity, relatively high insecticidal activity, and photochemical and hydrolytic instability. They are rapidly photo-oxidized when exposed to light and air, and although this is an advantage in certain insecticidal uses, it obviously renders them unsuitable for mothproofing applications.
Influence of bifentrin, a pyrethriod pesticide, on human colorectal HCT-116 cells attributed to alterations in oxidative stress involving mitochondrial apoptotic processes
Published in Journal of Toxicology and Environmental Health, Part A, 2020
Chayma Bouaziz, Imen Graiet, Amal Salah, Intidhar Ben Salem, Salwa Abid
Pyrethroids (PYR) are pesticides with high insecticidal activity that may disrupt neuronal excitability in target and non-target species. The accumulated evidence consistently showed that this neurophysiologic action is followed by alterations in motor, sensorimotor, neuromuscular, and thermoregulatory responses (Wolansky and Tornero-Velez 2013). According to the chemical structure, particularly the presence or absence of an α-cyano group at the carboxyl α position, pyrethroids are classified into two groups: type I and type II (Casida and Durkin 2013; Soderlund 2012). Type I pyrethroids lack an α-cyano group and produce repetitive nerve discharges leading mainly to body tremors. Exposure to Type II pyrethroids which contain α-cyano group produces salivation and seizures due to the stimulus-dependent nerve depolarization (Soderlund and Bloomquist 1989; Wolansky and Tornero-Velez 2013). Although pyrethroids predominant mechanism of action involves disturbances in central nervous system (CNS) functions and behavior (Wolansky and Tornero-Velez 2013), these pesticides also produce adverse effects in fish and mammals attributed to endocrine disruption associated with oxidative stress and apoptosis (Guo et al. 2017; Han et al. 2017; Hong et al. 2019).
Residues levels of pesticides in walnuts of Iran and associated health risks
Published in Human and Ecological Risk Assessment: An International Journal, 2021
Seyedeh Faezeh Taghizadeh, Hasan Badibostan, A. Wallace Hayes, John P. Giesy, Gholamreza Karimi
Organophosphorus pesticides (OPs) constitute a class of pesticides that act by inhibition of acetyl cholinesterase (AChE), which results in accumulation of the neurotransmitter acetylcholine, which can cause lethality by blocking transmission of impulses along nerves and in the brain. Therefore, quantifying OPs in foods and assessing risk is necessary (Songa and Okonkwo 2016). Carbamates (CBs), which are widely used in agricultural crops, also inhibit AChE. They are considered potential cytotoxic, genotoxic and immunotoxic agents that can affect several immune functions. Moreover, CBs have been associated with negative effects on cellular metabolic mechanisms, mitochondrial function, endocrine-disrupting activity, dementia, non-Hodgkin's lymphoma, and reproductive disorders (Della Pelle et al. 2018). Pyrethroids (PYs) are the most well-known and widely used representative pesticides. Due to their lipophilicity, PYs tend to accumulate into organisms and food items, and then separating PYs from matrices is difficult. Long-term exposure to pyrethroids, even at small doses, can cause chronic diseases including cardio-toxicity, immune-toxicity, and mutagenicity. Pyrethroids also have chronic effects on the male reproductive system, due to sperm aneuploidy, which is related to concentrations of metabolites of pyrethroids in urine. Another distinct mechanism of toxicity of PYs is allergenicity (Amjad et al. 2019). Nicotinoid (NC) pesticides with new modes of action and suitable selectivity are structurally distinct from the other classes of synthetic pesticides. They can cause serious effects on health and safety of consumers via developmental neurotoxicity (Sheets et al. 2016).
Effective preparation of magnetic molecularly imprinted polymer nanoparticle for the rapid and selective extraction of cyfluthrin from honeysuckle
Published in Journal of Biomaterials Science, Polymer Edition, 2020
Yanli Chen, Zenghui Xie, Lanyun Zhang, Xujia Hu
The pyrethroid insecticide is synthesized based on natural pyrethrines extracted from chrysanthemum[7,8]. Among the pyrethroid pesticides, cyfluthrin is a type II pyrethroid. It was registered in the USA in 1987 for the first time and is commonly used for pests such as aphids, cutworms, grain beetles, ants, silverfish, cockroaches, mosquitoes, termites, weevils, fleas, flies, and many others [9, 10], so cyfluthrin is one of the most used pyrethroid insecticides worldwide [11]. But after oral administration, cyfluthrin can be absorbed into blood circulation system, cross the blood-brain barrier, and poison the brain[7]. Therefore, cyfluthrin can affect the central nervous system function of non-target organisms.