Introduction

Due to the rapidly increasing human population, which is anticipated to reach 8.5 billion by 2030, the usage of pesticides in agriculture has expanded even more. For Plant protection and for crop improvement pesticides have emerged as one of the most powerful tools for the expansion of agriculture. Pesticides are substance, either natural or manmade that are intended to eradicate all pests and also used in a variety of industries, including agriculture, forestry, aquaculture, and the food sector. Pesticides are defined by the United Nations Organisation for Food and Agriculture (FAO) as any substance or combination of substances intended for growing, destroying, preventing, or controlling any pest, including vectors of human disease or animal disease, unwanted species of plants or animals, or which otherwise interfere with the production, processing, storage, transport, or marketing of food, agricultural products, wood and wood products, or animal feedstuffs which may be administered to animals for the control of insects, arachnids or other pests in or on their bodies [1].

Depending on their intended application, pesticides are divided into a number of different categories. Pesticides are primarily divided into four groups. Herbicides are weedkillers substances that kill weeds or stop the growth of unwanted plants or weeds in a field for example, parquet, atrazine, etc. Insecticides are used for insect control, fungicides are substances that destroy fungi and mould, such as Captan, Captofol, etc., while rodenticides are substances that kill rodents like rats, mice, and moles examples include anticoagulants, strychnine, etc. However, compared to the other three categories, insecticides are the most hazardous and acute. The toxicity of pesticides can vary depending on their formulation, their concentration, and the environmental factors they are exposed.

Insecticides are the synthetic compounds used to control various types of insects by killing or preventing them from engaging in undesirable behaviours or destructive. The use of insecticides slows growth and contributes to a variety of metabolic and reproductive issues. There are several wide groups of insecticides that are frequently used, including carbamate, organophosphate, pyrethroids, and nicotinoids. At present, about 30% of insecticides used worldwide are synthetic pyrethroids [2]. Due to their high efficacy at low concentrations, enhanced stability to photochemical, ease of microbial degradation, and very low human and animal toxicity, these insecticides were chosen over organochlorine, organophosphorus, and carbamate insecticides [3].

Resmethrin, Tetramethrin, Permethrin, Lambda-cyhalothrin, Deltamethrin and Cypermethrin are examples of synthetic pyrethroid insecticides that can have toxicological effects to aquatic organisms when used [4]. Humans and other terrestrial animals are regularly exposed to various pesticides through a variety of routes, including occupational exposure, residential exposure, and ingestion of pesticide-contaminated food and water. In addition to contaminating blood, pesticides also affect hormone and haematological functions, which induces toxicity. The different routes of administration of pesticides caused different signs and symptoms against the induced toxicity.

Aquatic organism, such as fish, are susceptible to several pesticides and their residues through a variety of pathways, such as rainwater or spray drifting from, gardens, farms and orchards. When the pesticides enter the water bodies they degrade the quality of water and affect the aquatic environment [5, 6]. Numerous fish mortalities have been reported all around the globe as a result of toxicants that are present in excess of the permitted limit [7]. Even at low doses, these chemicals represent a serious risk to people who consume them because they bioaccumulate in the aquatic species’ edible tissues [8].

A fourth generation pyrethroid insecticide Cypermethrin (CYP) is among widely applied insecticide worldwide and is used to control the cotton pests and ecto parasites like ticks and mites, of farm animals [9]. Cypermethrin has been identified as one of the significant pesticide linked with human health risks [10]. World Health Organisation (WHO) has allowed only three natural pesticides derivatives namely, Deltamethrin, Permethrin and alpha-Cypermethrin of pyrethroid group [11,12,13,14,15,16].

The available literature is widely known and confirmed that CYP concentrations in water bodies that are higher than the permitted range and are potentially detrimental to all aquatic life. According to Jaensson et al. high concentrations of CYP were found in the surface water [17]. It has a faster absorption rate as a result of its enhanced lipophilicity property [18]. Numerous disorders in insects, animals, birds, fish, and humans have been observed as a result of the extensive use of cypermethrin. Severe poisoning symptoms include abnormal facial sensations, dizziness, headaches, nausea, anorexia, and exhaustion. They also include vomiting and increased stomach secretions, irritation of the skin and eyes, chronic muscle spasms, coma, and convulsive attacks. Its hydrophobic properties also aid in the pesticide’s storage in an organism’s body fat, skin, liver, kidneys, adrenal glands, ovaries, and brain [19]. Cypermethrin can cross the placenta barrier, that’s why it can affects the neurological growth and physiological health of foetus [20]. The liver acts an important role in the purification and disintegration of dangerous chemicals like pesticides. The kidney has a major impact on the body’s ability to eliminate metabolic wastes. However, studies have revealed that cypermethrin poisoning affects the kidney and liver [21].

It has been investigated that CYP is toxic towards a variety of aquatic organisms, including fish, mussels, Daphnia, and others, as well as to lizards, goats, and human cells [22,23,24,25]. Cypermethrin concentrations in the environment are frequently below those that are fatal to many freshwater teleost [26,27,28,29]. Numerous studies [30,31,32] have been carried out to determine how synthetic pyrethroid and cypermethrin affect fish [33,34,35], however, there is limited information available regarding the comprehensive effects of cypermethrin during exposure and after exposure period. This review is concerned with the toxicological effects of pesticides and a brief overview of sources, classification of pesticides with an emphasis on the effects of CYP on fish as well as the mechanism of action and mode of toxicity of CYP and toxicity signs in several fish species have been illustrated. The primary controls and appropriate preventive measures that must be adopted are also discussed.

Classification of Pesticides

The term “Pesticides” is used to describe several classes that can either kill or prevent pests from entering the house, including insecticides, rodenticides fungicides, herbicides garden chemical wood preservatives and disinfectants. Modern pesticides are typically organic compounds. They include pesticides of both synthetic and plant origin. Synthetic pesticides are manmade chemicals, and do not occur in nature. They are categorized into various classes depending on the needs. Insecticides are significant pesticides that are used to kill or repel insects and related species. The classification of Insecticides depends upon number of factors and their hazardous effects. The pest organisms they kill their function, chemical composition, mode of entry and modes of action. Classification on the chemical composition and nature of their active ingredients is the most effective and common way to categorise the pesticides. It provides information about the chemical properties, physical properties and efficacy of the respective pesticides. The information is very useful in determining the mode of application, rate of application and preventive measures to be taken during application. Pesticides are divided into four major groups according to their chemical composition, as illustrated in Fig. 1. These groups are Organochlorines, Organophosphorus, Carbamates, Pyrethrins and Pyrethroids.

Fig. 1
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Classification of pesticides based on chemical structure

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Based on the differences in their chemical structures toxicity profiles, and, target sites, pyrethroids can be divided into two categories [36]. Type I pyrethroids are (Noncyanopyrethroids). They don’t have cyano group. In very short period they inactivate the sodium channels. Type II pyrethroids have alpha-cyano group. Due to the constant depolarization of the neuronal membrane, this alpha -cyano group keeps the sodium channels open for a long time [10]. Pyrethroids are produced through the synthesis of pyrethrins from Chrysanthemum cinerariifolium [37]. Cypermethrin is a type II man-made pyrethroid and a widely used broad-spectrum insecticide used extensively to eradicate ectoparasites from cotton, fruit, and vegetables, including moth pests, cockroaches, fleas, and termites. Also used as a primary ingredient in cockroach killer products (lal hit, baygon). Reactive oxygen species produced by CYP in the body lead to oxidative stress [38]. Furthermore, cypermethrin is a biodegradable insecticide and a fast acting neurotoxin with good contact and stomach action [39]. According to studies, in the central nervous system, pyrethroids like cypermethrin prolong the opening of sodium channels. It results in hyper excitation and hypo polarization of the neurons [40,41,42].

Consumption Pattern of Pesticides

In Asia, the use of pesticides is more than half of global consumption. India is the third-highest user of pesticides in Asia, after China and Turkey, and ranks 12th globally [43]. According to the FAOSTAT database World Health organization WHO (2019), between 1996 and 2016 pesticides use worldwide has increased by 46% (active ingredients measured in tonnes). Pyrethroids are from commonly used insecticides worldwide [44,45,46,47]. In India, the tropical environment is ideal for breeding of pest. Therefore, pesticides have a significant role in the development of agriculture and protection of public health. Generally, consumption pattern of pesticides in India is different from that of the world (Fig. 2). Insecticides is used on a large scale in India and the consumption of Herbicides is high in the world in general. Cypermethrin is widely used insecticide pesticides (Fig. 3). The consumption of cypermethrin has increased from 176 Metric Tonnes in 2017-18 to 674.75 Metric Tonnes in 2019-20. According to Government of India (GOI), In 2020–2021 its consumption is 343.91 Metric Tonnes and 340.93 Metric Tonnes in 2021–2022 (GOI 2020).

Fig. 2
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(Source: http://www.fao.org/faostat/en/#data) [43]

Pesticides use pattern—worldwide and India.

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Fig. 3
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(Source: http://ppqs.gov.in/statistical database) [48]

Consumption of major pesticide in Indian Agriculture.

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Pesticides Transport Pathway: Source

Pesticides are major source of ecosystem contamination because they can be transported through water, soil, and air as well as accumulate in crops. Figure 4 show the spraying operations from the ground or from the air are the main causes of agrochemical air pollution [49,50,51].

During its use and disposal, numerous routes allow cypermethrin to reach the aquatic environment. The atmospheric precipitation transport pesticides to water bodies. Many processes such as chemical process and micro-organism transforms pesticides into products that can be brought to surface water by water channel. There are numerous ways for cypermethrin-containing plant protection products can get into the aquatic environment. One of these is spray drift when applying it to crops, as well as surface runoff after rainfall [48].

Cypermethrin reaches watercourses following rainfall and surface run-off from the farms areas where spray tanker filling and emptying, and washing of spray equipment are done [52]. Besides commercial purposes Cypermethrin is also used as an insecticide in animal housing, industrial buildings, public spaces and homes. It can be used on textiles, floors and walls. Due to the disposal of items like timber, leachate from landfills has the potential to release cypermethrin into the environment. As a result of pesticide containers being disposed of in.

household waste, sometimes with unused product cypermethrin may also be present [53].

Fig. 4
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 A schematic illustration of the pesticides application routes. Pesticides can migrate across different ecosystems after being applied to soil or used to treat the crops, eventually accumulating in food chains or remaining as breakdown products

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Mechanism of Action

Numerous investigations have been made to explain the toxicity of cypermethrin, particularly in light of its effects on the neurological structure. The outcomes strongly recommend that the prime target location of pyrethroid insecticide and cypermethrin is the sodium channel in the nerve membrane in vertebrate nervous system. Cypermethrin, have same course of action as of organochlorines. They work by interacting with the nerve cell membrane and preventing the sodium channel’s ion gates from closing during repolarization. As a result, the nervous system’s ability to transmit signals is severely disrupted, causing spontaneous depolarization of the membranes or repetitive discharges. Figure 5 illustrates a schematic mechanism of action of CYP [54]. CYP leads the formation of cyanohydrin, which is then broken down into aldehydes and cyanides which later produce reactive oxygen species(ROS) [55]. ROS increase Ca++ levels and induce lipid peroxidation (LPO), which causes genotoxicity and cytotoxicity in organisms exposed to them. The neurotoxic activities of CYP, which are connected to the inhibition of AChE, are the main cause of their negative consequences. As a result, AChE is retained in synaptic gaps abnormally [56]. Cypermethrin interacts with Na + channels to causes neurotoxic effects via mediating hyperexcitability [38]. CYP intervene mitochondrial dysfunction by fluctuating mitochondrial proteome, causing apoptosis and induces oxidative stress, consequently lead to nigrostriatal dopaminergic neurodegeneration [57].

Fig. 5
figure 5

The mechanism of action of Cypermethrin. 1—CYP interrupts Na+ channel gate closing leading to multiple nerve impulses instead of the single one, which in turn leads to the release of the acetylcholine neurotransmitters and stimulation of other nerves. 2—Ca2+ concentration in the cytosol increases as a direct result of CYP’s action on calcium channels. 3—CYP leading to genotoxicity and cytotoxicity. 4—Inhibits the GABA receptor, resulting in excitability and convulsions. 5—ACh is retained pathologically in synaptic gaps as a result of CYP’s inhibition of AChE. 6—CYP is broken down into cyanohydrins, which are then converted into aldehydes and cyanides. 7—Aldehydes and cyanides produced by CYP cause ROS. 8—CYP affects adenosine triphosphatase [54]

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Cypermethrin-Mediated Toxicity in Fish

Sub-lethal amounts of pesticides cause various harmful effects on fish. Figure 6 systematically depicts cypermethrin (CYP) as a model pesticide that has hazardous effects on fish. In H. fossilis, CYP has disrupted the reproductive cycle [58] and in Odontesthes bonariensis, it has affected growth [59]. The effects of oxidative stress caused by CYP exposure in D. rerio were manifested as elevated levels of malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD) and LPO as well as altered concentrations of CAT, peroxidase (POD) and glutathione reductase (GR) in several tissues of T. putiora [60, 61]. The gills of C. striatus (CSG), C. catla (ICG), and L. rohita (LRG) had elevated levels of LPO and decreased levels of CAT, SOD and glutathione [62]. whereas the early life stages of L. rohita had increased levels of cortisol and GR [23]. However, due to unsystematic, careless, and reckless misuse, has a serious negative impact on the ecosystem in general and aquatic organism specifically. Among aquatic organisms, fish is regarded as an ideal sentry for assessing the hazardous impacts of contaminants. Studies have revealed that exposure to CYP has immunotoxic effects on Cyprinus carpio (common caro), apoptosis and DNA damage, histopathological alterations in C. carpio [63], hepatotoxicity in the Catla catla (Catla) [64], apoptotic changes and neurotoxicity in the brain of C. catla [65]. Additionally, exposure to CYP causes malformations in rohu (Labeo rohita) during the early developmental stages [12], causes oxidative stress and genotoxicity in exposed zebrafish (Danio rerio). Table 1 lists some of the harmful consequences that CYP-induced in different fish species.

Table 1 Provides a summary of the toxic effects of Cypermethrin in various fish species
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Fig. 6
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Shows the adverse effects of cypermethrin in fish

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Preventive Approach

Monitoring the use chemical pesticides is becoming more rigorous and conscious. There are numerous initiatives that are intended to promote best practises and safe use of cypermethrin and other biocides as well as veterinary medications. These include national codes of best practice European Union (EU) and national legislations and guidelines drawn up by many of organisations, such as the Forestry Commission. The development of novel agrochemicals with appropriate crop security has been done in combination with appropriate safety measures to boost pesticides effectiveness. By using natural (bio-control) agents including beneficial nematodes, insects, bacteria, and viruses, crop protection should be improved [90]. Therefore, the development of innovative biotechnology solutions has emerged as a crucial aspect of modern farming. Additionally, using well-maintained and suitable spraying equipment and practicing all necessary caution while handling pesticides can help to minimize exposure. Taking into account the peoples’ concern about pesticides residues in drinking water and food as well as optimization of pesticides handling in accordance with the laws and regulations could help to mitigate the overall adverse effects of pesticides on environment and human health.

The currently constructed wetlands (CWs) should be adapted because they have proven to be effective at removing pesticides from a variety of nonpoint sources, drainage, and agricultural runoffs in many different nations throughout the world [91]. Integrated pest control seeks to apply approaches that are (1) user-friendly, (2) environmentally friendly (low toxicity), (3) compatible with soil fertility, and (4) biologically effective for the elimination of chemicals tainted in the soil for commercial purposes [92].

Future research should emphasize on environmental and occupational exposure as well as their associated health risk for better understanding of pesticides use and management in the future. New technology, scientific methodology, and practical measures, such as a national implementation plan (NIP), laws that forbid the use of high risk pesticides and integrated pest management (IPM) should be implemented to minimise the detrimental effects of chemical pesticides contamination on the non-target organisms and the environment. There is a major concern regarding cypermethrin assessment under the safest limits due to its extensive use globally. In addition to being beneficial to the environment, animal and human health, managing pesticides use within permissible limits would also help aquaculture and wild fisheries provide livelihoods for people. Information regarding the permissible limits of commonly used pesticides should be collected and experiments for determining the safer levels or concentrations of the pesticides should be conducted.

It is also essential to disseminate the knowledge and scientific findings of exposure and environmental and occupational health risk assessments in order to provide scientific training for chemical pesticides application, to prevent the negative health effects from pesticide use, and promote safety for applicators and communities to support sustainable development. It is important to organise mass awareness and public education through seminars, symposiums, workshops, other teaching programmes. Development of bio-pesticides in addition to chemical pesticide, should be encouraged to reduce the pesticides contamination. In order to sustain a predefined pesticides concentration for an adequate period of time, Controlled release systems (CRS) of pesticides are advised. It allow decrease in unwanted pesticides losses caused by various reasons, relocation of an dynamic element to a targeted surface from the entrapped compartments and generate the desired effect on the target pests [93].

Evaluating the Protection of various formulants for non-target species which is based on complete and reliable data on their effect, improving the ability to predict, in silico approaches in toxicology and understanding a required assessment of chronic effect of adjustments are included in the preventive strategies.

The core preventive approach, however, is the proper and justifiable application of chemicals during crop cultivation: in light of growing environmental consciousness and a need to minimise the impact of agriculture on ecosystems and the planet, wise pesticides usage is a modern-day necessity.

Conclusion

A-cyano pyrethroid insecticide Cypermethrin, is extremely efficient and active against a variety of pests in numerous food and non-food commodities. Pesticides have increased agricultural productivity and offered countless benefits to society, making them a boon for farmers and industrial employees. There is a significant works which demonstrate toxic effect in different organisms, including fish, induced by cypermethrin still the evaluation of molecular mechanism of cypermethrin induced toxicity at genome and proteome level is required. This literature addressed the biological mechanisms of action on various fish species as well as the underlying biological impact of fish by pyrethroids contaminated water. Additionally, research on toxicology has shown that individuals respond differently to the lethality of pyrethroids. The toxicological information currently available might be used to have a clear understanding of the potential for these insecticides in causing risks to environmental health. However, more study and research are needed on the various biochemical toxicological molecular and environmental aspects of these chemicals so that their toxicological potential in environment can be validated and possibly help to design some potential insecticides which could be environment friendly and beneficial for human health. This current review sheds light on the mechanisms underlying CYP toxicity in fish and toxicity signs in several fish species have been illustrated and provides insight for further research evaluating the toxic effects of pyrethroid insecticides.