Mini Review - European Journal of Zoological Research ( 2021) Volume 9, Issue 1
Received: 07-Jan-2021 Published: 22-Jan-2021
Pesticides are chemical compounds that are harmful to creatures that impact the development of plants, such as fungus, insects, and weeds. Pesticides, on the other hand, help farmers grow food more intensively and simply, but they also have numerous negative externalities since they kill many animal species, including mammals, earthworms, and bees. Pesticides have been among the most harmful and long-lasting pollutants discharged into the environment. After decades of usage in agriculture, their toxicity and propensity to accumulate in soils and the food chain were identified, and these pesticides have played a significant part in the deterioration of natural resources, ecosystems, and biodiversity that we see today. Our pesticide-intensive agriculture practice has been highlighted as a significant contributor to biodiversity loss. "Pesticides can last for decades in the environment, posing a global danger to the entire ecological system that relies on food supply. Excessive use and misuse of pesticides causes pollution of nearby soil and water supplies, resulting in biodiversity loss, the extinction of beneficial insect populations that function as natural pest foes, and a reduction in the nutritional content of food.
Pesticides are used to kill pests and insects that cause crop damage. Pesticides of various types have been used to protect crops for millennia. A combination of honey and arsenic was employed to control ants in the 1600s. Farmers in the United States began utilising chemicals such as nicotine sulphate, calcium arsenate, and sulphur for fieldrelated purposes in the late 1800s, but their efforts were fruitless due to the rudimentary methods of administration . Pesticides are beneficial to crops, yet they have a significant detrimental influence on the ecosystem. Excessive pesticide usage has the potential to destroy biodiversity. The existence of many birds, aquatic creatures, and animals is threatened by toxic chemicals. Pesticides pose a threat to the environment’s long-term viability and global stability. Pesticides have a wide range of effects on wildlife, putting animals in urban, suburban, and rural settings in undue danger. Beyond Pesticides classifies “wildlife” as any creature that has not been tamed or utilized in a laboratory. Bees, birds, small animals, fish, other aquatic creatures, and soil biota are all examples of this. Pesticides can have an influence on wildlife by explicit or implicit application, such as pesticide drift, secondary poisoning, runoff into local bodies of water, or groundwater pollution. Some animals may get sprayed directly, while others may eat vegetation or prey that has been subject to pesticides. In a broad variety of species, pesticide exposure has been related to cancer, endocrine disruption, reproductive impacts, neurotoxicity, kidney damage, birth abnormalities, and developmental alterations. Pesticide exposure can change an organism’s behavior, affecting its capacity to live. Certain herbicides, for example, can impair bird singing abilities, making it difficult to lure partners and reproduce. Pesticides can also impair a bird’s capacity to care for offspring, resulting in the death of its young. Systemic insecticides have sublethal effects on bee movement, feeding habits, and navigation, even at “near-infinitesimal” doses. Hormone-mimicking pesticides classed as endocrine disruptors have been linked to a variety of deformations. Hermaphroditic abnormalities in frogs, pseudo-hermaphrodite polar bears with penis-like stumps, panthers with atrophied testicles, and intersex fish in rivers across the United States are all effects of these substances. At exposure levels deemed “safe” by the US Environmental Protection Agency, reproductive abnormalities have been found in reptiles, fish mammals, birds, and mollusks. Plant biodiversity benefits bees and other pollinating insects, while herbicides reduce plant communities. Herbicides’ negative impacts can be seen in birds, mammals, fish, insects, amphibians, reptiles, and people. These toxins decimate the plant kingdom’s biodiversity. Pesticides kill one-fifth of honeybee colonies in Europe, according to the United States Fish and Wildlife Service (USFWS) .
As increasingly complicated and extensive research is released, the projected economic costs of biodiversity losses-including the value of pollinator services, “beneficial” predators, birds, and aquatic life are always shifting. According to previous research, the cost of biodiversity losses may be more than $1.1 billion each year. We now know that biodiversity loss may cost hundreds of billions of dollars each year. Natural pest management, a critical agricultural service, is valued at $100 billion each year. Researchers have also observed a continuous reduction in these insects as a result of pesticide exposure, as well as a general decline in biodiversity. It might be deduced that as beneficial insect populations fall, so would their capacity to provide ecological services, reducing the number of species accessible for hunting, fishing, and observation. The demand for these leisure activities will remain constant but the supply (availability) will decrease, resulting in an increase in the amount of money spent by Americans each year.
Natural insecticides are quite safe to use. Although they are made from plants, they are just as dangerous as their synthetic equivalents. Pheromones and microbial pesticides, for example, are biologically based insecticides that are typically safer than standard chemical pesticides. The efficacy and toxicity of pesticides should always be assessed on an individual basis. An insecticidal soap is a popular organic insecticide. In conjunction with fatty acids, insecticide soap consists of potassium or sodium salt. While one of the safest insecticides, its efficacy is limited. The insecticide soap must contact the bug directly when it is moist in order to be efficient. It is effective after it’s dried. Insects exoskeletons can enter and cause the cells inside of the insecticide soap to collapse. They are found in fatty acids. This pesticide has been popular since it is one of the most safe, which makes it easy to use on garden plants and vegetables for people or pets. Neem Oil is a new, fast growing form of natural insecticide. The tropical neem tree generates oilseeds that have been identified as detrimental for the growth and feeding of insects. Neem’s minimal toxicity to people and pets, including certain moths, beetles and caterpillars, is highly effective against a number of insects. As a pesticide, extract from the chrysanthemum flower of pyrethrum may be utilised. This natural insecticide is not particularly mammalian toxic but is efficient against certain species of kidneys, caterpillars and leafhoppers. Pyrethrum is not long-lasting and must often be administered.
Pesticide effect on wildlife
Pesticides are administered to forests, rangeland aquatic habitats, farming, rights-of-way, urban turf, and gardens in a variety of ways using various delivery systems. For certain species, their extensive usage inevitably creates contact with pesticide residues. Acute or prolonged exposure can lead to pesticide toxicity to animals. In addition, the pesticides can influence wildlife through subsequent exposure or indirect animal or habitat consequences. Pesticide application effect on wild life is based on different types of poisoning. They are as follows:
(a) Acute poisoning
Some insecticides may be killed or poisoned by short exposure. Examples include acute wild animal poisoning by birds induced by the foraging of pesticide-treated plants or insects or the intake of pesticide-treating granules, sprayed or seeds by surfacing or sprays, and by pesticide residues transported to pools, streams or rivers. In general, a relatively brief period of acute wildlife poisoning has an influence on a highly restricted geographical region and is associated with a single insecticide
(b) Chronic poisoning
Exposure of wildlife to non-lethal pesticide doses can lead to chronic toxicity over a lengthy period of time. The most famous example is organochlorine pesticide DDT (through metabolic DDE), which is chronic in animals, when it is reproduced by specific birds of prey. The animal death caused by prolonged exposure was associated with DDT and other organochorinous agents including dieldrin, endrin and chlordane. Organochlorine insecticides in various places may represent a risk to over-wintering migratory birds.
(c) Secondary poisoning
When an animal feeds prey species with pesticide residue, pesticides can have an effect on the wild through secondary poisoning. Secondary poisoning examples include prey animals growing sick after feeding on a dead animal (the accumulation and movements of persistent chemicals in food chains for wildlife) or dying due to acute exposure to a pesticide (Health and Environment 1995) .
(d) Indirect effects
A pesticide might have an effect on wildlife other than direct or indirect toxicity. When a component of their environment or food source is changed, pesticides can have an influence on animals indirectly. Insect pollinator can be decreased to impact plant pollination, for example, herbicides can limit food, cover and vested areas needed for pesticides, birds and mammals; insecticides can reduce insects supplied to birds or fish species. An emergent topic that is challenging to explore is the study of indirect impacts.
Pesticides can be effective in managing weeds, insects, and other pests when applied correctly. On the other side, if the user does not follow the label instructions, they may harm animals. Non-target birds, animals, fish, aquatic invertebrates, insect pollinators, and plants are examples of non-target wildlife. Implementing organic techniques for your crop production or animal rearing, as well as supporting organic agriculture rather than conventional agriculture, which relies on pesticide use, are two strategies to prevent the detrimental effects of pesticides not only on wildlife but we the humans can also stay safe. Transcend Pesticides promote organic agriculture as a means of improving land husbandry and decreasing harmful chemical exposures to animals. The pesticide reform movement, citing pesticide issues such as groundwater pollution and runoff, as well as drift, sees organic as the answer to these major environmental challenges.
People are historically assumed that the only genuine method to clear gardens and crop fields of pests was to use hazardous chemical pesticides. Pesticide usage has resulted in soil contamination and air pollution, and some of these chemicals take years, if not decades, to break down. These insecticides are hazardous to both animal plants and human health. Fortunately, many organic compounds are equally effective. When organic pesticides are applied, the effects of pesticides on soil microorganisms are less intrusive.
People must abandon the use of hazardous pesticides in favour of increasing organic pesticides that decompose fast in the sun and in the soil. The quicker a chemical degrades, the faster the soil may revert to its natural form. The majority of organic insecticides are likewise non-toxic to humans and pets. They are readily removed from fruits and vegetables, making them healthier to consume for ourselves and our family.