Economically and Environmentally Sustainable Enhanced Oil Recovery. M. R. Islam
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When arsenic is heated, it oxidizes and releases an odor similar to that of garlic. Striking various arsenic-containing minerals with a hammer might also release the characteristic odor. At ordinary pressure, arsenic, like carbon dioxide, does not melt but sublimes directly into vapor. Liquid arsenic only forms under high pressure.
Curiously, alchemists gave emphasis on characterizing material in terms of mercury and arsenic. Mercury, lead and arsenic are effective mitotic poisons (turbagens) at particular concentrations, due to their known affinity for thiol groups and induce various types of spindle disturbances. New Science classifies these clastogenic effects to be S-dependent. The availability of cations affect the number of aberrations produced quantitatively. Plants, following lower exposure, regain normalcy on being allowed to recover (Patra et al., 2004). However, as usual New Science does not distinguish between natural arsenic and processed arsenic, thereby obscuring any usefulness of the research findings.
Historically, New Scientists5 have focused on medicinal effects of arsenic when it comes to finding any positive aspect of arsenic. Citations of medicinal applications range from Ancient China to Ancient Greece through Ancient India (Doyle, 2009). Hippocrates (469–377 BC) recommended arseniko as a tonic whilst Dioscorides (c. 54–68AD) recommended it for asthma. A Greek surgeon‐herbalist working in Nero’s army, he made extensive observations on asthma, including the use of realgar mixed with resin, inhaled as a smoke for the relief of cough or taken as a potion for asthma. Reportedly, it was used to kill Britanicus in 55 AD during the reign of Emperor Nero (37–68AD).
Egyptologists claim that ancient Egyptians used arsenic to harden copper at least 3000 years ago. This was confirmed by Islam et al. (2010), who reviewed ancient technologies and found them to be totally sustainable because they used no artificial mass or energy source. They also discussed the fact that such chemicals were added in the embalming fluid during processing of mummies. Of course, the Medieval Islamic golden era saw numerous applications through alchemy. However, the role of arsenic in material processing has drawn little attention from New Scientists. In Europe, during the New Science era, the use of arsenic is synonymous with processed derivatives of arsenic, rather than naturally occurring version. Graeme and Pollack (1998) described how artificial processing of arsenic can render both mercury and arsenic into toxic agents. They pointed out that Greeks and Romans continued to use natural arsenic throughout the Medieval era for various medical purposes. Even during the 1800s, arsenic remained in use for medical purposes in treating leukemia, psoriasis, and asthma. Of interest is the fact that the Fowler’s solution was not withdrawn from the US market until the 1950s. Meanwhile, Erlich and Bertheim produced nearly 1000 compounds of arsenic to be used in the treatment of syphilis; the use of such compounds was not curtailed until after the advent of penicillin in 1943. The arsenic-containing drug melarsoprol (Mel B) is still the drug of choice for treating African trypanosomiasis at the meningoencephalitic stage 1, 2, 3, 4. Note that commercial use of electricity began in 1870s. Although it is unknown among New scientists, the use of electricity for thermal alteration renders a process unsustainable. In the meantime, while natural penicillin was discovered in 1928 by Alexander Fleming, Professor of Bacteriology at St. Mary’s Hospital in London, mass production was possible only after synthetic version of penicillin was created. This transformation from natural penicillin to Benzylpenicillin (C16H18N2O4S) first took place in 1942 (Fischer and Ganellin, 2006). This transition from natural to artificial is symbolic of what has happened in sustainability considerations, natural being sustainable while artificial (or synthetic) being unsustainable.
Arsenic may occur in an inorganic or an organic form. The inorganic arsenic compounds include the arsenites, the arsenates, and elemental arsenic. The organic arsenic compounds include arsine and its organic derivatives. In modern era, synthetic or inorganic arsenic has been the only one used for commercial applications. In all these applications, arsenic is never in its natural form and all the byproducts are inherently toxic to the environment. For instance, arsenic is a byproduct of the smelting process for many metal ores such as, cobalt, gold, lead, nickel, and zinc. The natural form of arsenic was used in ancient and medieval era for similar applications. It seems even in modern Europe as late as 19th century arsenic was used in paints and dyes for clothes, paper, and wallpaper (Meharg 2003). Even then, arsenic for the production of green pigments following the synthesis in the late eighteenth century of copper arsenite was in its toxic form. These pigments were widely used in wallpapers. In damp rooms, fungi living on the wallpaper paste turned the arsenic salts into highly toxic trimethylarsine. Arsenic pigments were responsible for untold numbers of cases of chronic illness and many deaths (Meharg, 2003).
The source of both organic and inorganic arsenicals are naturally occurring minerals, such as, arsenopyrite (FeAsS), realgar (As4S4) and orpiment (As2S3). As these erode, they react with moisture and oxygen to form arsenites and arsenates that are water soluble and consequently end up in both surface and groundwater. Some of these chemical forms and oxidation states cause acute and chronic adverse health effects, including cancer (Hughes, 2002). The metabolism involves reduction to a trivalent state and oxidative methylation to a pentavalent state. The trivalent arsenicals, including those methylated, have more potent toxic properties than the pentavalent arsenicals. The exact mechanism of the action of arsenic is not known, but several hypotheses have been proposed. What is missing in this analysis is the role of artificial chemicals. At a biochemical level, inorganic arsenic in the pentavalent state may replace phosphate in several reactions. In the trivalent state, inorganic and organic (methylated) arsenic may react with critical thiols in proteins and inhibit their activity. However, this ‘organic’ in New Science doesn’t mean that an artificial state has been avoided. As such, potential mechanisms include genotoxicity, altered DNA methylation, oxidative stress, altered cell proliferation, co-carcinogenesis, and tumor promotion cannot be tracked to artificial chemicals. A better understanding of the mechanism(s) of action of arsenic will make a more confident determination of the risks associated with exposure to this chemical.
In surface waters, these chemicals can be absorbed by algae that then convert them to arsenosugars, arsinolipids and arsenobetaine. In surface waters, these can be absorbed by algae that then convert them to arsenosugars, arsinolipids and arsenobetaine. Fish and other forms of marine life feed on these algae and concentrate the arsenic compounds. When the same arsenic compounds are absorbed by plants, similar but less complex reactions take place and further dilution occurs when they are passed on to grains.
Figure 2.5 Shows the pathway followed by the original naturally occurring ore, containing arsenic. Most arsenic in the terrestrial environment is found in rocks and soils. Arsenic in surface and ground water is mostly a mixture of arsenite and arsenate. Although New Science designates various components in molecular form, in reality molecules are fictitious and never exist in isolation. During the pre-New Science era chemical equations were not written in molecular or atomic form, hence the words, such as ‘air’ (instead of Oxygen), ‘moisture’ (instead of H2O) and chosen.
Figure 2.5 Pathway followed by arsenic chemicals.
This figure shows that in order for arsenic to travel natural pathway, the entire chain of air and moisture has to be free of synthetic chemicals. In the post industrial revolution, major sources of arsenic include the combustion of coal, nonferrous metal smelting, and the burning of agricultural wastes. These are inherently toxic to the environment. Similarly, each chemical