Negative Effects of Silver on The Environment

Silver with a symbol Ag, an element that has been positioned as the 47th in the periodic table is a rare though naturally occurring precious metal found deposited in a mineral ore with other elements. Its atomic weight is 107.8, together with the two natural isotopes of 108.90% and 106.90% with the abundance of 48 and 52% respectively. It is widely spread metal in the environment the can also be found in some other forms apart from metal such as salt and nanoparticles. Due to its special properties for instance; thermal conductivity and high electoral, it has had wide range of applications. In ancient civilization, it was used in the making of the jewelry, utensils, coins, building materials and even making clothes. Since it has the bacteriostatic properties, silver compounds have been one major component that has acquire its usage in not only in filters but also in the important apparatus used in the purification of the drugs, beverages, drinking water and also water in the swimming pool.

Silver has low mobility and low crustal in water and therefore is usually found in the extremely low concentrations in the natural water. An example of the highest concentration of the silver in the fresh water was recorded in Colorado River in USA with 38 ug/litre. The movement in the global biochemical of the silver particles are considered to be characterized with its release in the water, atmosphere, and to the land through the anthropogenic and natural sources. The atmospheric forms of the silver that are emitted may include: silver sulfate (Ag2SO4). Silver halides, silver carbonate (Ag2CO3), metallic silver and silver sulfide.

Almost 50% of the silver that are released in the environment comes from the industries are therefore are transported at about 100- 200km and lastly are deposited in the precipitation form. Silver that are emitted from the coal-fired plants can end up accumulating in the soil, and in such a case, the silver emitted is therefore greatly immobilized through precipitation giving out the insoluble salts and through the complexation by the organic matter, manganese, iron oxides and clays. In USA, silver lost to the environment in 1978 was at around 2.5 million kilograms, and most of it was to the aquatic and to the terrestrial ecosystem. The photographic industries had the record of almost 47% of the silver that was emitted to the atmosphere, land and water from the anthropogenic sources.

The terrestrial and aquatic ecosystem tends to receive most of the silver that are lost in the environment and hence they are immobilized in different types such as metals, alloys and mineral. These silver which may mostly be in the form of nanoparticles (AgNPs), which negatively affect the environment which obviously contain both the biotic and the abiotic organism. The aquatic ecosystem receives like an estimate of 150000kg in a year, with which this may be from the mine tailing, electroplating and photographic industry. The agricultural lands on the other hand receives an emission of that ranges from 75000 to 80000kg of silver in a year and this is through the photoprocessing of the wastes in the sewage sledges.

The terrestrial animals that are negatively affected includes the mammals, more specifically the human being who are exposed to the nanoparticles which are the forms of the silver. Even though the medical industry has greatly invested in the nanoparticles to find the prescription drugs that aims at the reducing of the cancer cell, these forms of silver have been linked to genetic and lung damages. These nanoparticles get into or penetrates in the body through inhalations, and also in a transcutaneous manner; hence affecting the health of many people especially those working in the industries.

These nanoparticle size allows the endocytosis to enter the cell and transcytosis to penetrate to many cells of the body, probably one after another. In the result, when inhaled, they spread to the nervous ends of the olfactive epithelium to the upstream of the axons and lastly to the olfactive bulbs which are in the brain and this is the place where they affect the neurons. Apart from that, they also reach the lung through blood. In addition to that, they get in the spleen, lymph nodes, heart and therefore tend to trigger oxidative stress, both pro-oxidant and antioxidant activities, inflammation and can cause the modification of distribution of the mitochondria. These effects though might be felt depending on the dose exerted on the person.

The aquatic life also suffers the negative effects of the silver emissions. This is simply because the large amount of the nanoparticles is found in both the fresh water and marine aquatic ecosystem. The Nano silver are the new pollutant to the aquatic life and they are highly dangerous to the aquatic life. It is toxic to many organisms like the phytoplankton, which are at the top of the food chain, the marine invertebrates like snail, oysters and different fish types that are not fully matured.

Silver can also be transferred from the mother fish to the embryos. The passing of contaminants from the mother fish to the next generation makes the embryos be exposed while in the early stages of life, which will later in life affects them in terms of their health and reproduction hence decreased population of the fish. Nanosilver is quite dangerous than the lumps of silver to the many species of the shellfish and fish simply because the tiny particles cover the huge surface area hence giving the relatively great chance to increasingly get into the interaction with the ecosystem.

To add, the nanoparticles has negative impacts on the soil, killing the soil microbes that sustains plant life. The Nanoparticles get into the land through wastewater which are in turn get accumulated in sewage sludge. The sewage sludge is then disposed through land application since it tends to be as important as a fertilizer. The Nanoparticles have been used in different commodities such as the sunscreens and sim cards of phones. Because they are consumed in such commodities, they are emitted in the ecosystem; that is in the air, water and soil.

References

Colman, Ben, N., & Canada. (2010). Effects of ice cover on dissolved oxygen in Silver Lake, Ontario. Ottawa: Environment Canada.

Kunisch, S., Boehm, S. A., & Boppel, M. (2011). From grey to silver: Managing the Demograhic change successfully. Heidlberg: Spring-Verlag Berlin Heid

References

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