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Global distillation or the Grasshopper effect is the geochemical process by which certain chemicals, most notably persistent organic pollutants (POPs), are vaporized and transported from warmer to colder regions of the Earth, particularly the poles and mountain tops, where they condense. Other chemicals include acidifying acids (SOx) and heavy metals. [1] The first documented use of the term was in 1975 by E.D. Goldberg to describe the vaporization of synthetic halogenated hydrocarbons which is enhanced by the presence of water. [2] However, this effect was only believed to occur within a defined “pollution band” in the mid-latitudes of the Northern Hemisphere. Soon after, evidence of this effect was found in arctic food as well as its atmosphere. [3] Since then, relatively high concentrations of POPs have been found in the Arctic soil and water, as well as the bodies of animals and people who live there, even though most of the chemicals have not been used in the region in appreciable amounts. [4] [5]
The global distillation process can be understood using the same principles that explain distillations used to make liquor or purify chemicals in a laboratory. [6] In these processes, a substance is vaporized at a relatively high temperature, and then the vapor travels to an area of lower temperature where it condenses. A similar phenomenon occurs on a global scale for certain chemicals. When these chemicals are released into the environment, some evaporate when ambient temperatures are warm and blow around on winds until temperatures are cooler, when condensation occurs. Drops in temperature large enough to result in deposition can occur when chemicals are blown from warmer to cooler climates, or when seasons change. The net effect is atmospheric transport from low to high latitude and altitude. Since global distillation is a relatively slow process that relies on successive evaporation/condensation cycles, it is only effective for semi-volatile chemicals that break down very slowly in the environment, like DDT, polychlorinated biphenyls, and lindane.
POPs are known for their resistance to degradation and their toxicity to humans and wildlife. [7] Although most are now banned, their long-lasting capabilities have allowed them to remain in the atmosphere, soil, and water, where vaporization can occur. [6] Two of the most common POPs that participate in global distillation are dichlorodiphenyltrichloroethane (DDT) and polychlorinated biphenyls (PCBs). [6] DDT, once used as an insecticide, is now known to contribute to obesity and hypertension, and is a possible carcinogen. PCBs, on the other hand, can cause developmental effects in children and babies. Both chemicals are also endocrine disruptors, which involve bodily hormones. However, in 2004, the Stockholm Convention pledged to reduce or eliminate POP usage due to their negative effects. [8]
Global distillation has a profound impact on the ocean, primarily through the long-range transport of toxic chemicals that accumulate in marine ecosystems. [9] Once in the ocean, these pollutants can be absorbed by marine organisms and enter the food chain, affecting everything from plankton to large marine mammals. [6] Chemicals can accumulate in the fatty tissues of fish and other sea creatures, leading to toxic concentrations that can disrupt the health of marine ecosystems. [1] This contamination jeopardizes marine biodiversity and affects fisheries, which many coastal communities rely on for sustenance and livelihoods.
Animals in polar areas are at high risk because they often rely on fat-rich diets, which increase their exposure to accumulated toxic chemicals. Species like polar bears, seals, and whales, which are top predators, accumulate high levels of POPs due to biomagnification—where these pollutants become more concentrated as they move up the food chain. [9] [6] These chemicals can lead to developmental abnormalities in wildlife, threatening population sustainability. Additionally, migratory species, such as birds and marine mammals, can carry these pollutants over vast distances, spreading contamination far beyond their point of origin. [1] The toxic buildup in these species not only affects their health and survival rates but also disrupts the broader ecological balance of these fragile environments.
Global distillation also has significant consequences for human health, particularly in indigenous and remote communities that rely on traditional diets, such as fatty fish and marine mammals. [10] Global distillation can cause social inequalities, as poleward communities such as the Inuit receive the most direct affects. [1] As these chemicals accumulate in the environment, there is also the risk of them entering water supplies, which further amplifies the potential for human exposure. In this way, global distillation poses a significant threat not only to the environment but also to the long-term health and well-being of vulnerable populations around the world.
This process is closely linked to climate change. As global temperatures continue to rise, chemicals are more readily volatilized, further increasing atmospheric pollution. [11] The Arctic warms at a faster rate, amplifying this effect. Ice is a known storage location for POPs and other chemicals, and when it melts, pollutants risk redistribution through ocean currents. [12] [11] Changes in weather patterns are another effect of climate change, which may also alter the pathways through which chemicals are transported. [11] If they find their way into the water supply, toxic substances can pose a threat to ecosystems and human health. [10] Global distillation and climate change create a positive feedback loop that worsens environmental degradation, making it harder to mitigate the harmful impacts on biodiversity and human well-being.
Mitigation techniques for global distillation focus on reducing the release of POPs and enhancing the detection and removal of these substances from the environment. One major advancement is the development of cleaner industrial processes that minimize the production of hazardous chemicals, particularly through improved manufacturing practices and alternative chemicals. For example, the use of non-toxic alternatives in pesticides, solvents, and industrial chemicals can greatly reduce the risk of these substances entering the atmosphere. Additionally, advancements in air filtration technologies, such as high-efficiency particulate air (HEPA) filters and activated carbon systems, can help capture airborne pollutants before they spread into the atmosphere or settle in colder regions. Reduction of fatty acids in the diet may help to reduce human contamination. [8] Moreover, satellite and remote sensing technologies enable better tracking of the movement and deposition of POPs, providing valuable data to inform mitigation strategies. [7] By investing in innovative clean technologies and improving pollutant tracking systems, it is possible to reduce the long-range transport of harmful chemicals and limit their environmental impact.
There is also the possibility for policy implementation, which primarily focuses on the creation of international agreements and regulatory frameworks aimed at reducing the production and use of POPs. A key example is the Stockholm Convention, a global treaty that seeks to eliminate or restrict the use of the most dangerous chemicals, including many involved in global distillation. [8] By enforcing stricter regulations on the manufacturing and disposal of these substances, countries can collectively work to reduce the chemicals released into the atmosphere and, subsequently, their transport to polar regions. [7] On a regional level, cross-border collaborations between countries in areas like the Arctic are essential to monitor and address the movement of pollutants.
A pollutant or novel entity is a substance or energy introduced into the environment that has undesired effect, or adversely affects the usefulness of a resource. These can be both naturally forming or anthropogenic in origin. Pollutants result in environmental pollution or become of public health concern when they reach a concentration high enough to have significant negative impacts.
Bioaccumulation is the gradual accumulation of substances, such as pesticides or other chemicals, in an organism. Bioaccumulation occurs when an organism absorbs a substance faster than it can be lost or eliminated by catabolism and excretion. Thus, the longer the biological half-life of a toxic substance, the greater the risk of chronic poisoning, even if environmental levels of the toxin are not very high. Bioaccumulation, for example in fish, can be predicted by models. Hypothesis for molecular size cutoff criteria for use as bioaccumulation potential indicators are not supported by data. Biotransformation can strongly modify bioaccumulation of chemicals in an organism.
Water pollution is the contamination of water bodies, with a negative impact on their uses. It is usually a result of human activities. Water bodies include lakes, rivers, oceans, aquifers, reservoirs and groundwater. Water pollution results when contaminants mix with these water bodies. Contaminants can come from one of four main sources. These are sewage discharges, industrial activities, agricultural activities, and urban runoff including stormwater. Water pollution may affect either surface water or groundwater. This form of pollution can lead to many problems. One is the degradation of aquatic ecosystems. Another is spreading water-borne diseases when people use polluted water for drinking or irrigation. Water pollution also reduces the ecosystem services such as drinking water provided by the water resource.
Aquatic toxicology is the study of the effects of manufactured chemicals and other anthropogenic and natural materials and activities on aquatic organisms at various levels of organization, from subcellular through individual organisms to communities and ecosystems. Aquatic toxicology is a multidisciplinary field which integrates toxicology, aquatic ecology and aquatic chemistry.
Stockholm Convention on Persistent Organic Pollutants is an international environmental treaty, signed on 22 May 2001 in Stockholm and effective from 17 May 2004, that aims to eliminate or restrict the production and use of persistent organic pollutants (POPs).
Phytoremediation technologies use living plants to clean up soil, air and water contaminated with hazardous contaminants. It is defined as "the use of green plants and the associated microorganisms, along with proper soil amendments and agronomic techniques to either contain, remove or render toxic environmental contaminants harmless". The term is an amalgam of the Greek phyto (plant) and Latin remedium. Although attractive for its cost, phytoremediation has not been demonstrated to redress any significant environmental challenge to the extent that contaminated space has been reclaimed.
Persistent organic pollutants (POPs) are organic compounds that are resistant to degradation through chemical, biological, and photolytic processes. They are toxic and adversely affect human health and the environment around the world. Because they can be transported by wind and water, most POPs generated in one country can and do affect people and wildlife far from where they are used and released.
Dieldrin is an organochlorine compound originally produced in 1948 by J. Hyman & Co, Denver, as an insecticide. Dieldrin is closely related to aldrin, which reacts further to form dieldrin. Aldrin is not toxic to insects; it is oxidized in the insect to form dieldrin which is the active compound. Both dieldrin and aldrin are named after the Diels-Alder reaction which is used to form aldrin from a mixture of norbornadiene and hexachlorocyclopentadiene.
Marine pollution occurs when substances used or spread by humans, such as industrial, agricultural and residential waste, particles, noise, excess carbon dioxide or invasive organisms enter the ocean and cause harmful effects there. The majority of this waste (80%) comes from land-based activity, although marine transportation significantly contributes as well. It is a combination of chemicals and trash, most of which comes from land sources and is washed or blown into the ocean. This pollution results in damage to the environment, to the health of all organisms, and to economic structures worldwide. Since most inputs come from land, either via the rivers, sewage or the atmosphere, it means that continental shelves are more vulnerable to pollution. Air pollution is also a contributing factor by carrying off iron, carbonic acid, nitrogen, silicon, sulfur, pesticides or dust particles into the ocean. The pollution often comes from nonpoint sources such as agricultural runoff, wind-blown debris, and dust. These nonpoint sources are largely due to runoff that enters the ocean through rivers, but wind-blown debris and dust can also play a role, as these pollutants can settle into waterways and oceans. Pathways of pollution include direct discharge, land runoff, ship pollution, bilge pollution, atmospheric pollution and, potentially, deep sea mining.
Toxaphene was an insecticide used primarily for cotton in the southern United States during the late 1960s and the 1970s. Toxaphene is a mixture of over 670 different chemicals and is produced by reacting chlorine gas with camphene. It can be most commonly found as a yellow to amber waxy solid.
Endrin is an organochlorine compound with the chemical formula C12H8Cl6O that was first produced in 1950 by Shell and Velsicol Chemical Corporation. It was primarily used as an insecticide, as well as a rodenticide and piscicide. It is a colourless, odorless solid, although commercial samples are often off-white. Endrin was manufactured as an emulsifiable solution known commercially as Endrex. The compound became infamous as a persistent organic pollutant and for this reason it is banned in many countries.
Soil contamination, soil pollution, or land pollution as a part of land degradation is caused by the presence of xenobiotic (human-made) chemicals or other alteration in the natural soil environment. It is typically caused by industrial activity, agricultural chemicals or improper disposal of waste. The most common chemicals involved are petroleum hydrocarbons, polynuclear aromatic hydrocarbons, solvents, pesticides, lead, and other heavy metals. Contamination is correlated with the degree of industrialization and intensity of chemical substance. The concern over soil contamination stems primarily from health risks, from direct contact with the contaminated soil, vapour from the contaminants, or from secondary contamination of water supplies within and underlying the soil. Mapping of contaminated soil sites and the resulting clean ups are time-consuming and expensive tasks, and require expertise in geology, hydrology, chemistry, computer modelling, and GIS in Environmental Contamination, as well as an appreciation of the history of industrial chemistry.
Methoxychlor is a synthetic organochloride insecticide, now obsolete. Tradenames for methoxychlor include Chemform, Maralate, Methoxo, Methoxcide, Metox, and Moxie.
The Aarhus Protocol on Persistent Organic Pollutants, a 1998 protocol on persistent organic pollutants (POPs), is an addition to the 1979 Geneva Convention on Long-Range Transboundary Air Pollution (LRTAP). The Protocol seeks "to control, reduce or eliminate discharge, emissions and losses of persistent organic pollutants" in Europe, some former Soviet Union countries, and the United States, in order to reduce their transboundary fluxes so as to protect human health and the environment from adverse effects.
Persistent, bioaccumulative and toxic substances (PBTs) are a class of compounds that have high resistance to degradation from abiotic and biotic factors, high mobility in the environment and high toxicity. Because of these factors PBTs have been observed to have a high order of bioaccumulation and biomagnification, very long retention times in various media, and widespread distribution across the globe. Most PBTs in the environment are either created through industry or are unintentional byproducts.
Pollution in the Arctic Ocean is primarily the result of economic activities carried out on land, which is sources from locally, regionally, and globally origins. There is also the inclusion of industrial development in the Arctic region, northern rivers, and the effects of military activities, particularly nuclear activity – as well as the influx of pollutants from other regions of the world.However, the Arctic Ocean remains relatively clean compared to other marine regions of the world.
A glacier stream is a channelized area that is formed by a glacier in which liquid water accumulates and flows. Glacial streams are also commonly referred to as "glacier stream" or/and "glacial meltwater stream". The movement of the water is influenced and directed by gravity and the melting of ice. The melting of ice forms different types of glacial streams such as supraglacial, englacial, subglacial and proglacial streams. Water enters supraglacial streams that sit at the top of the glacier via filtering through snow in the accumulation zone and forming slush pools at the FIRN zone. The water accumulates on top of the glacier in supraglacial lakes and into supraglacial stream channels. The meltwater then flows through various different streams either entering inside the glacier into englacial channels or under the glacier into subglacial channels. Finally, the water leaves the glacier through proglacial streams or lakes. Proglacial streams do not only act as the terminus point but can also receive meltwater. Glacial streams can play a significant role in energy exchange and in the transport of meltwater and sediment.
Bioremediation of petroleum contaminated environments is a process in which the biological pathways within microorganisms or plants are used to degrade or sequester toxic hydrocarbons, heavy metals, and other volatile organic compounds found within fossil fuels. Oil spills happen frequently at varying degrees along with all aspects of the petroleum supply chain, presenting a complex array of issues for both environmental and public health. While traditional cleanup methods such as chemical or manual containment and removal often result in rapid results, bioremediation is less labor-intensive, expensive, and averts chemical or mechanical damage. The efficiency and effectiveness of bioremediation efforts are based on maintaining ideal conditions, such as pH, RED-OX potential, temperature, moisture, oxygen abundance, nutrient availability, soil composition, and pollutant structure, for the desired organism or biological pathway to facilitate reactions. Three main types of bioremediation used for petroleum spills include microbial remediation, phytoremediation, and mycoremediation. Bioremediation has been implemented in various notable oil spills including the 1989 Exxon Valdez incident where the application of fertilizer on affected shoreline increased rates of biodegradation.
Contaminants of emerging concern (CECs) is a term used by water quality professionals to describe pollutants that have been detected in environmental monitoring samples, that may cause ecological or human health impacts, and typically are not regulated under current environmental laws. Sources of these pollutants include agriculture, urban runoff and ordinary household products and pharmaceuticals that are disposed to sewage treatment plants and subsequently discharged to surface waters.
Brynjulf Ottar (1918–1988) was a Norwegian atmospheric chemist who served as the first director of the Norwegian Institute for Air Research. In the 1970s, his work on the long-range transport of air pollution helped to alert the world to the problem of acid rain; later, he was one of the first scientists to describe the mechanism of global distillation, by which pollutants travel from mid-latitude parts of Earth to the Arctic.