Introduction
Pesticides are an inclusive term for rodenticides, fungicides, insecticides, herbicides, and nematicides. They are critical in increasing yield and helping farmers utilize less land while producing large yields. While they help improve food security worldwide, the aftermath of their application is catastrophic for the environment, animals, plants, and human beings.
The chemicals pose serious health issues such as cancer, impaired movement in fish, death of indigenous trees and shrubs, killing beneficial microorganisms in the soil, contaminating soil, ground, and surface water, and polluting the air (Buck et al., 2020; de Solla et al., 2023; Hao et al., 2021). As such, one pressing question is whether the government should ban large-scale use, given research indicating that the problems they cause can be short-term, acute, or chronic (de Souza et al., 2020, p. 23). In this light, the government should ban the large-scale use of pesticides and herbicides because pesticides negatively impact human and animal health and contaminate the surface, groundwater, soil, vegetation, and air, translating to health issues in non-target organisms and the death of beneficial soil microorganisms.
Discussion
Primarily, pesticides harm the health of humans and animals. Analysis of the day-to-day logistics from sourcing raw materials to the application of end products shows how several people are impacted by the use and transportation of the chemicals (Ali et al., 2021). Farmers, production workers, formulators, and sprayers risk health issues without appropriate protective gear. Additionally, the chemical compounds they contain, such as dioxins, cause cancer and can also lead to other health effects, such as heart failure (Hao et al., 2021, p. 401). Other human health effects include disruptions in endocrine function, oxidative stress, impaired cognition, hormonal imbalances, and immune suppression (Ali et al., 2021).
Animals are primarily affected by DDT pesticides, which cause reduced eggshell thickness (Buck et al., 2020, p. 4). Analysis shows that over 60 percent of health issues resulting from pesticide residues in animals can be passed to humans through consumption (Ali et al., 2021). A similar analysis conducted in northern Tenerife showed abundant traces of DDE chemicals, such as polychlorinated biphenyls, in the eggshells of Kestrels (Buck et al., 2020, p. 5). This is alarming, as such chemicals were banned several years ago.
Additionally, pesticides contaminate ground and surface water over time. Since the chemicals in these pesticides do not readily degrade, they end up in water bodies through evaporation, runoff, and precipitation. Analysis of surface water shows that the various types of these chemicals differ in concentration, with insecticides and herbicides being the most common.
Statistically, 70% of rivers in America contain two or more mixtures of pesticides (Stackpoole et al., 2021, p. 2). Further still, more than 221 pesticide compounds have been identified in these drinking sources. Of that number, 21 include transformation products, and 143 are from significant compounds such as organochlorides (Buck et al., 2020, p. 3).
According to Bexfield et al. (2020), approximately 41% of US wells also register traces of these chemicals. The analysis shows that these chemicals ultimately contaminate water sources and reduce their purity (Bexfield et al., 2020, p. 367). Heavy use of these chemicals in agriculture has led to concentrations in some rivers approaching the US government’s unacceptable limit (USGS, 2020). Such extremities lead to the death of aquatic life and even translate to critical conditions such as infertility and malformation.
Moreover, the persistent chemicals found in pesticides pollute the streams and the soil where they are used. They essentially penetrate deeper into the soil through runoff and leaching (Bexfield et al., 2020). In the long run, they alter the soil’s composition by reacting with its natural chemicals, thereby changing the chemical environment. According to Ali et al. (2021), several chemicals with such properties include endrin, heptachlor, DDT, and lindane.
In some cases, pesticides leave traces of heavy metals in the soil, which plants absorb and animals and humans eventually consume (Buck et al., 2020, p. 4). Investigations by Hao et al. (2021) show that the effects typically include reduced soil respiration, averaging 25%, rendering such land unfit for agriculture or highly dependent on nutrient supplementation. However, reversing such conditions is usually challenging, as in most cases the land is left unused for a period, resulting in reduced agricultural production.
Furthermore, chemicals also contaminate the unintended air, vegetation, and water when used indiscriminately. According to Ali et al. (2021), during the application of these chemicals, some quantities (approximately 25%) are lost due to drifting (Ali et al., 2021, p. 324). This is because 70-90% of these chemicals, such as ester-formulated pesticides, are volatile and can easily contaminate other areas (Ali et al., 2021, p. 324). Therefore, on average, 80% of the environment is contaminated (Ali et al., 2021, p. 324).
Areas with intense use of these chemicals have shown traces of pesticides in fog, snow, rainwater, and air. Herbicides are known to reduce vegetation populations. A good example shown by Stackpoole et al. (2021) is the case of phenoxy herbicides, which clear and kill shrubs and trees.
Another good example is glyphosate, which is known to reduce seed quality over time. Consequently, about 75 plant species could go extinct if glyphosate use is continued (Ali et al., 2021). Even clopyralid reduces potato yield, reducing both quantity and quality.
In addition, toxic levels of chemicals affect non-target organisms. Lethal doses are prescribed in such products during formulation, often at levels that make them effective for animals that cannot manage them (Bexfield et al., 2020, p. 366). For example, chlorpyrifos is known to kill fish in water bodies near the application field (Buck et al., 2020, p. 4).
Likewise, animals that consume such water are affected, with river dolphins facing extinction threats due to the application of these compounds (Buck et al., 2020, p. 3). Trifluralin, a commonly used herbicide, has been linked to vertebral deformities observed in some fish (Buck et al., 2020, p. 4). As a result, affected fish find it difficult to swim against the current and to breathe (Buck et al., 2020, p. 5). Insects and birds have become prey to the unintended chemical traps that terminate rodents such as rats and rabbits. Analysis of data from researchers shows a significant reduction in insect biomass of up to 70 percent (Ali et al., 2021).
Similarly, North America, Canada, and Europe are experiencing a 42 percent decline in species (Stackpoole et al., 2021). Pollination in fields has reduced the population of pollinating bees by 30%(Ali et al., 2021). Therefore, if no appropriate measures are taken to minimize or stop the use of pesticides, the population of some species will be significantly reduced.
Pesticides degrade soil fertility on a large scale. Chemicals from pesticides kill the living microorganisms that play an active role in decomposition. In some cases, as in nitrogen-fixing plants, converting nitrogen to nitrates is impossible, as some chemicals, such as organochlorides, disrupt the nitrogen conversion process (de Souza et al., 2020, p. 23). Discriminate use of chemicals, such as glyphosate, reduces the activity and growth of nitrogen-fixing bacteria (de Souza et al., 2020, p. 23).
Another similar case is when herbicides and pesticides kill mycorrhizal fungi (Hao et al., 2021). Mycorrhizal fungus helps uptake nutrients in plants during the process of absorption as they live within the roots of a plant (de Souza et al., 2020, p. 20). Similarly, triclopyr reduces pore size in the fungus, and mycorrhizal growth is inhibited when Trifluralin and oryzalin have been used (Hao et Al., 2021). Heavy soil treatment with pesticides can disrupt the natural microbial community, eliminating many organisms.
Additionally, several studies have shown that metal ion deterioration in soil is a serious problem. This condition results from the depletion of vital soil metals, such as zinc and manganese (de Souza et al., 2020, p. 23). This is a condition resulting from chelation and ligation (de Souza et al., 2020).
Pesticides have chelating effects and interact with other metal ions in the soil. Analysis shows that zinc, copper, nickel, iron, magnesium, and manganese ions can react with thiocyanate methyl, carbofuran, acephate, and carbofuran (de Souza et al., 2020, p. 23). When they react with these chemicals, their composition in the soil is reduced and altered, thereby affecting soil richness.
Despite these, pesticides have improved food security in the United States and worldwide. Worldwide statistics on hunger show that the number of people without access to adequate food is increasing. This has been achieved through crop loss protection and vector disease control.
According to de Souza et al. (2020), the use of pesticides, such as herbicides and insecticides, has contributed to reductions in vector populations that transmit crop diseases from one plant to another. For crops to grow successfully, they face stiff competition from over 30,000 weeds, 10,000 crop-feeding insects, and over 3,000 worms (Bexfield et al., 2020, p. 367). These challenges do not end in the field as they continue after harvesting.
Harvested crops are vulnerable to rodents, molds, and bugs during storage. Since crops cannot survive based on survival of the fittest, killing competitive weeds, worms, insects, and other animals on the farm is the most appropriate measure. However, natural and organic ways can replace pesticides, such as crop rotation, natural predators, homemade organic repellants, companion planting, manure, and physical barriers (Göldel, 2020).
Adopting such organic and natural ways is beneficial in both the long- and short-term. Crop rotation improves soil structure and composition, helps mitigate pests and diseases, preserves moisture, and improves the soil’s water-holding capacity. Manure, an alternative to synthetic fertilizers, can quickly replenish nutrients such as phosphorus and nitrogen without leaving toxic residues (Göldel, 2020). Using herbicides can be replaced with mowing, grazing, fire, tillage, or hand removal.
Similarly, companion planting has been used for some time (Göldel, 2020). This phenomenon requires that beneficial plants, through shade, nutrients, disease, or pest protection, be grown together to protect each other. The same concept applies to natural predators, which help control pest populations. Managing pests requires keeping their natural enemies close, such as using plant-eating insects around farms (Göldel, 2020). These methods are constructive when put into practice effectively.
Conclusion
In conclusion, banning the large-scale use of pesticides will help control most of their negative impacts, both short- and long-term. To summarize, the paper has analyzed the impacts of pesticides on animal and human health, plants, the environment, soil-dwelling microorganisms, and aquatic life, as well as on surface and groundwater contamination. On the one hand, results show that pesticides degrade human and animal health and destroy soil fertility on a large scale. Moreover, excessive concentrations of chemicals harm non-target species and pollute the surrounding air, plants, and water sources when applied without proper control. Lastly, they also contaminate ground and surface water over prolonged periods.
On the other hand, there are benefits to using pesticides, such as providing food security by maximizing the use of small land and killing competing weeds, worms, rodents, and insects. Nevertheless, this does not warrant their use, as they can be replaced with natural and organic pest and disease control methods, such as crop rotation and physical barriers. Harmful pesticides should be banned, as these alternatives have few side effects and can provide both short- and long-term benefits.
References
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