Development of Industry Causes Enviromental pollution
explanatory Essay
1266 words
An increase in industrial, agricultural practices and several anthropogenic activities adds a significant amount of heavy metals in soil and water. Presence of these metals beyond the threshold limit is toxic for the flora and fauna of the surroundings. So, there is a need for removing the harmful heavy metals from the environment. Conventional methods such as precipitation, evaporation, electroplating, ion exchange, membrane processes, etc. have been ineffective because of technical and economic issues. Biosorption is a potential bioremediation technique that can be used for the removal of pollutants from aqueous medium and soil by the help of biosorbents (algae, fungi, bacteria, plants etc.). For increasing the biosorption capacity of biosorbents, they can be modified physically, chemically and genetically. Various factors affect the biosorption activity such as initial pH, temperature, bacterial activities and kinetics. This study describes the bacterial adsorbents, their modification and mechanism for removal of copper. A brief description of Langmuir and Freundlich isotherm modelling is provided in this paper.
Keywords: Bioremediation, biosorption, biosorbent, bacteria, heavy metals, copper.
Introduction
The intensive development of industry, agricultural practices and modern technologies are leading to the release of significant amount of contaminants to the environment (Ayres, 1992). Metals are inorganic form of contaminants whose extensive use has caused significant environmental pollution that mainly affects soil, watercourses, atmosphere and living systems (Kasassi et al., 2008). Mercury, lead, cadmium and chromium (VI) are considered as toxic metals; whereas, copper, nickel, cobalt and zinc are not as toxic, but their e...
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In this essay, the author
- Explains that industrial, agricultural, and anthropogenic activities add heavy metals to soil and water. biosorption is a potential bioremediation technique that can be used for the removal of pollutants by biosorbents.
- Opines that increasing/activating the binding sites on the biomass surface could be an effective approach for enhancing biosorption capacity.
- Explains that biosorbents lack specificity in metal-binding, which may cause difficulties in the recovery and recycling of the desired metals. genetic engineering has the potential to improve or redesign microorganisms, such as escherichia coli.
- Explains immobilization techniques such as entrapment and cross linking have been found to be practical for biosorption. immobilizing microorganisms within a polymeric matrix has demonstrated greater potential, especially in packed or fluidized bed reactors.
- Explains that metals are inorganic contaminants whose extensive use has caused significant environmental pollution. bioremediation through bioreduction and biosorption is an attractive option for removal of metal contaminants.
- Explains that biosorbents are the microbial biomass responsible for inactive metal uptake. bacillus sp. has high metal sequestering properties among the bacteria, and staphylococcus saprophyticus is a beneficial bacterium for biosorption
- Explains that the success of a chemical pretreatment is strongly dependent on the cellular components of the biomass.
- Describes the toxicity, accumulation, and tissue distribution of copper in the blue crab callinectes sapidus acclimated to different salinities.
- Introduces amt-bioclaim, a new wastewater treatment and metal recovery technology, in fundamental and applied biohydrometallurgy.
- Explains the effects of the neurospora crassa gene on the bioaccumulation of heavy metals by bacterial cells.
- Describes the results of studies on chromium(vi) adsorption–desorption using immobilized fungal biomass.
Related
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- Contaminants Of Chromiumexplanatory essayAdsorption reactions are another promising method of removing Cr(VI) from environmental systems. These reactions play an important role in determining the fate of chromium in natural systems. They affect whether the contaminant will enter into the ground or surface water or remain in the soil, thus influencing mobility and transport, as well as the concentration at which the contaminant will be present. Hydrous oxides of Al and Fe are often used as adsorbents in such reactions, as they are common in the natural envi...
In this essay, the author
- Explains that cr(vi) has several common industrial uses, including in manufacturing and electroplating, and is often released into the environment due to spills associated with these industries.
- Explains that the fate of chromium in the environment is controlled by redox conversions, precipitation, dissolution, and adsorption reactions.
- Explains that adsorption reactions are another promising method of removing cr(vi) from environmental systems.
- Explains that iron and aluminum oxides are rarely found in pure forms in the environment; compounds and mineral substitutions often exist. the objective of this research is to determine adsorption trends of chromium on ferrihydrite minerals.
- Explains that at concentrations of aluminum higher than 30%, the aluminum did not combine with the ferrihydrite, but rather precipitated out and formed a separate compound.
- Explains the adsorption samples comprised of 2 g l-1 ferrihydrite mineral, 1 mm chromate, nacl to provide background electrolyte concentration, and hcl or naoh to adjust the ph.
- Explains that positive charge on the solution will affect crystallite size, morphology, surface area, solubility, and surface chemistry. other studies concluded that chromium adsorption on al substitution is not significantly affected.
- Explains that iron and aluminium hydroxides have been extensively studied as adsorbents for cr. little is known about how al substitution impacts on fe.
- Explains that the results of this study provide a spectroscopic characterization of ferrihydrite substituted on al and cr (vi)
858 wordsRead More - Environmental Effects of Cadmiumcomparative essayOne of the well-known disasters in history is Thailand’s cadmium contamination due to zinc mining by humans. It has been a topic talked about due to its significant impact on the land it has affected and its influence on human health. There have been a number of treatment/removal plans introduced for Cadmium contamination such as Phytoremediation (using plants to remove heavy metal contamination from soil). “However, effective treatment depends on using an appropriate cadmium hyperaccumulator plant that is suitable for growth within the local environmental condition” (Phaenark et al., 2009).
In this essay, the author
- Explains that the mae sot district in the tak province is famous for its rice-based crop cultivations. however, due to its neighboring zinc mines, the soils within these areas have resulted in cd contamination.
- Explains that phytoremediation is a form of method used to remove metals from the soil using hyperaccumulator plants.
- Explains that cadmium toxicity is one of the most harmful heavy metal contaminations. it is a by-product during mining, extraction or removing impurities from ores with copper, lead and zinc.
- Compares the cd concentrations found within rice and soybean grains to the safety standards.
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In this essay, the author
- Explains that high concentrations of arsenic are found naturally in groundwater worldwide and pose a potential health hazard to humans from long-term exposure.
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- Explains that ntim, mitra, and peng, z., used iron oxide coated multiwall carbon nanotubes to remove trace arsenic to meet drinking water standards.
- Compares heavy metal ions sorption onto activated carbon, carbon nanotubes, and carbon-encapsulated magnetic nanoparticles.
- Summarizes rao, lu, c., and su, f.'s paper on the sorption of divalent metal ions from aqueous solution by carbon nanotubes.
- Cites tofighy, mohammadi, and upadhyayula for their review of carbon nanotube technology for removal of contaminants in drinking water.
- Describes velickovic, z, vukovic g, marinkovic a, moldovan, m.s., peric-grujic, a.a.
- Cites mohan, d., pittman, c.u. (2007), the journal of hazardous materials, 142(1-2),1-53.
- Explains the use of iron oxide coated multiwall carbon nanotubes for removal of trace arsenic to meet drinking water standards.
1192 wordsRead More - Arsenite Detoxificationexplanatory essay...ic units called plasmids, and this characteristic has made them highly acquiescent to genetic study. For this reason, we know a lot about microbial ArsCbased resistance determinants, including crystal structures of ArsC proteins from numerous bacteria (as reviewed in Mukhopadhyay et al. 2002). This type of resistance determinant is very widespread in the prokaryotic world; more than 100 Ars operons had been sequenced by 2002 (Mukhopadhyay et al. 2002), and this number will be substantially higher now. ArsC is a small (13–16 kilodaltons) protein that is establish in the cytoplasm of the microbial cell and mediates the reduction of arsenate to arsenite, with glutaredoxin, glutathione or thioredoxin supplying the reducing power for this transformation (Silver and Phung 2005). The toxic arsenite is then excreted by an energy-requiring (ATP-dependent) efflux pump, ArsB.
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795 wordsRead More - The Recycling Of Recyclingcomparative essayThe heavy metal that leaks from the landfill will accumulate in the soil, causing erosion (Raymond 2011). The lead, mercury, arsenic and chromium blocks the air from entering the soil and decrease the plant roots ‘ability of absorb water and nutrients (Raymond 2011). Zinc has negative effect on microorganisms in the soil and therefore it interrupts the decomposition of organic matters. Moreover, various heavy metals accumulate differently in plantations (Raymond 2011). For example, lead accumulates more in the leaves of the plants and arsenic is found mostly in the fruits of the plants (Raymond 2011). These metals all have direct and indirect effects on human health. For example, lead poisons interference with brain development and causes irreversible neuro-damages. Arsenic is usually associated with skin erosion and circulatory issues. Cadmium has the ability to disrupt or disable certain essential enzymes in living organisms and causes renal damages. The heavy metals, leaking out from the landfill will pollute the soil and eventually harm all living organism on the land, including
In this essay, the author
- Explains that the paper envelope is recyclable and putting it to the recycling trash bin. however, downstream cycling results in dioxins and other toxic gases that pollute the air.
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- Explains that the paper envelope contains inorganic compounds that are not combustible and remain in the ashes after incineration.
- Explains that landfills have negative effects on surrounding areas including ground water contamination, air pollution, and human health problems.
- Explains that landfills damage soil and organisms. lead, mercury, arsenic and chromium block the air from entering the soil, and zinc interrupts the decomposition of organic matter.
- Concludes that the paper envelope would travel to an incinerator, being burned into ashes, and then the remains would be buried in a landfill. people should stop consuming unnecessary staff and live more environmentally friendly.
802 wordsRead More - Arsenicanalytical essaySchroeder, Henry A., M.D., 1974, The Poisons Around Us; Toxic Metals in Food, Air, and Water: Indiana University Press
In this essay, the author
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- Opines that mrs. maybrick should have been acquitted of murdering her husband with arsenic based on circumstantial evidence.
- Analyzes how the "unhappily married man" was treated for guillain-barré, but had hyperkeratosis, weak muscles, and white transverse lines upon his nails. his wife confessed to putting the deadly element in the form of an ant-killer.
- Recommends that dimercaprol be given intramuscularly every four hours for 48 hours, followed by 3 mg/kg twice daily for eight days. these injections are painful and locally irritant.
- Analyzes bagla, pallava, and kaiser, jocelyn, india's spreading health crisis draws global arsenic experts: science.
- Reviews debra lynn dadd's book the nontoxic home & office; protecting yourself and your family from everyday toxics and health hazards.
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- Cites navarro, blanca, sayas, mara-josé, atienza, angel, and león, pilar, in an unhappily married man with thick soles.
- Cites schroeder, henry a., m.d. (the poisons around us); toxic metals in food, air, and water.
- Explains that stone, richard, 1994, trail of toxins leads through conference rooms in dallas: science.
- Explains that arsenic has been known since the 4th century bc, though it wasn't described as an element until 1649.
- Explains that arsenic is a potent poison that works quickly, especially when ingested in large doses. symptoms include inflammation of the gastric and intestinal areas along with severe vomiting and diarrhea spotted with blood.
- Explains that if arsenic does not kill you outright, it causes cancer. in córdoba, argentina, the cancer causes 23 percent of the deaths.
- Explains that arsenic poses a serious threat to the lives of nearly all humans because of its toxicity and amount in the world.
3034 wordsRead More - Essay On Zeolitesexplanatory essayNatural zeolites have shown good ion-exchange capacities for cations, such as ammonium and heavy metal ions. In order to have high adsorption capacity for organic matter and anions, modification of natural zeolites can be performed by several methods, such as acid treatment, ion exchange, and surfactant functionalization. Besides the removal of heavy metals, natural zeolites are used to to remove ammonia and humic acid from the suface waters. The removal of the contaminants depends on pH value, initial concentration of humic acid and ammonia, temperature and contact time. Zeolite shows best performance of ammonia and humic acid removal at the pH close to natural water. Furthermore, natural and modified zeolites are used t...
In this essay, the author
- Explains that natural or synthetic zeolites are microporous crystalline aluminosilicates. they have unique ion exchange and sorption properties.
- Explains that the removal of ammonium is done by zeolite cation exchange from the recirculating hatchery waters.
- Explains that natural zeolite-containing consumer products can be obtained in the us, japan, and germany. they act as deodorizing agents and to remove odors caused by nh3 in water.
- Explains that natural phillipsite and specific synthetic zeolites are used as filter media to remove ammonium during hemodialysis of a kidney patient.
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- Explains that zeolites are used in various ways in the construction industry and to produce construction materials.
879 wordsRead More - Speciation and Origin of Particulate Copper in Runoff Water from a Mediterranean Vineyard Catchmentexplanatory essayal., 1994; Dawson and Macklin, 1998), and thereby its toxicity. It is therefore of interest to characterise the speciation o copper transported by runoff water leaving areas with highly contaminated soils. This is especially the case in south France which presents the largest vineyard area in the world and a Mediterranean rain all regime leading to intense sur ace runoff and erosion processes (Gomer, 1994; Albaladejo et al., 1995). Besides, it must be pointed out that copper seems to be predominantly transported by suspended matter in runoff water (e.g. Gilbin et al., 2000; Xue et al., 2000), which can be related to the affinity of copper or sorption on some components o suspended sediments like organic matter, clay minerals and hydrous metal oxides (Flemming and Trevors, 1989).
In this essay, the author
- Explains the soluble exchangeable fraction, of ten low (emmerichetal, 1982; shuman, 1986; sahaetal., 1991; keller and vedy, 1994).
- Explains the acid-soluble fraction, usually high in carbonated soils (misra and tiwari, 1966; cavallaro and mcbride, 1984).
- Explains that the reducible fraction, associated with iron and manganese oxides and oxyhydroxides in the organic matter content is low.
- Explains the oxidizable raction, preponderant in soils with a high organic matter content.
- Explains how they used a mixing model to estimate the specific contribution of the plateau, terraced slopes, and footslope-depression system, to the suspended matter flux at the catchment outlet.
- Explains that the total copper content of suspended matter was two to four times higher than in the 15–25 cm soil layer. the residual copper fraction was dominant over the whole catchment.
- Describes the study event that took place on 4 november 1994 after the autumn resumption of rain.
- Explains cu, zn, cd, fe, and mn in soils near a copper smelter.
- Cites xue, sigg, and ga chter, 2000. transport o cu, zn and cd in a.
- Explains that fungicide treatments have led to large copper contents of the topsoils of most vineyards. this paper examines the contamination of surface waters by copper in a mediterranean wine-growing catchment.
- Explains that copper has been used to protect vines against fungus disease since the end of the eighteenth century.
- Explains that total copper content is an inadequate variable to characterise the behavioural differences of copper in soil, suspended matter or sediment.
- Describes the chemical extractions proposed by tessieretal, which are used to identify the major water pathways and contributing areas to runoff in catchments.
- Describes the study area in the he rault river basin, which has been occupied almost exclusively by vineyards.
- Describes the hydro-meteorological equipment of the roujan catchment described in detail by voltzetal.
- Explains that the suspended matter was collected using water samples taken manually at the catchment outlet and in the surface runoff during the storm flow event of 4 and 5 november 1994.
- Explains that all water samples were microfiltered using a 0.45-mm filter. the suspended matter content was determined by weighing after oven-drying the microfiltrates (48 h at 105 0c).
- Explains that there are a large number of protocols or sequential chemical extractions, with different domains of validity. they opted for the frequently used protocol of tessieretal.
- Analyzes the physicochemical analyses and measurements of total copper contents in soil using samples taken from pedological profiles representative of the different morphological situations.
- Explains that the morphopedological units of the catchment had some mineralogical characteristics in common and a few specific characteristics.
- Explains that copper content profiles showed an accumulation in the topsoil or all morphopedological units. the surface accumulation can be explained by the nature of the soil, the majority of which was calcareous with a ph of over 8.
- Explains the phenomenon of hysteresis in suspended matter content as a function of flow rate at the outlet.
- Analyzes the impact of the plateau, terraces, and footslope-depression system on the flow rate suspended matter concentration relationship.
- Demonstrates the small spatial variability of these two fractions and confirms their secondary role in copper fixation and transport.
- Explains that the reducible copper content increased progressively during the storm flow, correlated to that of iron bound to oxides.
- Explains that the residual copper content evolved in several stages, including a decline and an increase in the downstream system.
- Explains that fungicide treatments in vineyards can lead to a large contamination of surface waters by particulate copper during storm events.
4356 wordsRead More - Banana Peel Lead Adsorption and the Removal of Heavy Metalsanalytical essayResults showed that the adsorption efficiency is highly dependent on quanttity of adsorbent added. This was expectedas with increasing conc...
In this essay, the author
- Analyzes the effects of initial dosage on lead adsorption by using banana peel as an absorbent for heavy metal removal.
- Explains that the dosage of adsorbent on 0.8g and 2.8g, its have the negative on the conentration of lead.
- Explains that the adsorption efficiency is highly dependent on quanttity of absorbent added. with increasing concentration, more surfaces become available for metal uptake.
- Analyzes the effect of contact time on lead adsorption by using icp analysis. the result shows that the trend of the percentage removal of lead was not stable.
- Explains that the amount of metal adsorption increases with contact time, which is typical of banana peel. at 20 minutes, the percentage of removal of lead was the minimum one.
- Explains that the driving force of mass transfer between liquid and solid phase decreases with time elapse, and the metal ions have to pass through the deeper surface of the pores for binding.
- Explains that the adsorption efficiency factor can affect from the evaluate of contact time. adsorption rate of lead on banana peel was found to be relatively much faster than those reported for some others.
- Explains that higher speed lowered the metal removal, not allowing enough time to metal ions to adsorb.
565 wordsRead More - Inorganic Compounds in Seafoodexplanatory essayAll over the world one of the most consumed foods that all most every culture eats is seafood. There are even full societies that rely fully on the nourishment that they receive from the seafood that they catch and eat. Because of this there is a very large problem with the pollution of the water around the world that these fish are caught from. This pollution can cause serious harm to the people that consume these fish and can even kill out entire villages and towns. One of these many pollutants that are found in many fish around the world are inorganic metals and metal compounds that are not normally found in the human body. These inorganic compounds can cause harm to the human body because of this there has been a plethora of research that has been done and is still going on to fix this. This research involves ways to get rid of the pollution in the fish before they are consumed as well as finding why these fish are being polluted and stop the source of this. There has also been many things that have been done by the EPA and many government groups around the world to make sure that this problem does not get worse as well as being able to rid the seafood that already has the inorganic materials in them from these compounds.
In this essay, the author
- Explains that inorganic metals and metal compounds are found in many fish around the world. this pollution can cause serious harm to the people that consume them and can even kill out entire villages and towns.
- Explains that the most common heavy metals found in fish are arsenic (as), copper (cu), lead (pb), mercury (hg) and cadmium (cd).
- Explains the different ways in which chemicals make it into the environment, such as hg, pb, as, and cd.
- Explains that bioaccumulation is the process by which a larger animal receives more of the toxic metal by eating more and more smaller animals that have the toxin. the world health organization attributes 143,000 deaths to lead poisoning.
- Explains how exposure to methyl-mercury through fish intake has caused sever problems around the world. one of the most famous examples is in the 1950's in minamata, japan.
- Explains that the minamata, japan outbreak is the most famous example of inorganic poisoning.
- Explains that research is being done around the world to find out which fish and bodies of water have the most inorganic materials in them and if they are harmful to the people that eat them.
- Explains heavy metal concentrations (ug metal g"' wet wt) in fish from the black sea coasts.
- Explains that the amount of inorganic material in fish in puerto rico is on the rise due to industrial advancement, and the lack of regulation in that part of the world.
- Explains the avg. as conc., est. inorg, and the hazard quotient.
- Explains the cancer risk in fish if eaten multiple times a week. the government advised people not to eat fish more than once every week and pregnant women and children should avoid it all together.
- Explains the amount of lead and cadmium found in some species of fish that are located in different rivers around egypt. each study shows the research that is going on around the world to test the fish for these chemicals.
- Explains that all studies have the same extraction method in which each of these fish is tested by using an aa or atomic absorption spectrometer.
- Explains that the presence of inorganic metals in fish is a common thing around the world due to the heavy pollution that is involved in every country.
1928 wordsRead More