Fear God (UNDER CONSTRUCTION)

FEAR GOD

Revelation 14: 7 And I saw another angel fly in the midst of heaven, having the everlasting gospel to preach unto them that dwell on the earth, and to every nation, and kindred, and tongue, and people, 7Saying with a loud voice, Fear God, and give glory to him; for the hour of his judgment is come: and worship him that made heaven, and earth, and the sea, and the fountains of waters. 8And there followed another angel, saying, Babylon is fallen, is fallen, that great city, because she made all nations drink of the wine of the wrath of her fornication. 8And there followed another angel, saying, Babylon is fallen, is fallen, that great city, because she made all nations drink of the wine of the wrath of her fornication. 9And the third angel followed them, saying with a loud voice, If any man worship the beast and his image, and receive his mark in his forehead, or in his hand, 10The same shall drink of the wine of the wrath of God, which is poured out without mixture into the cup of his indignation; and he shall be tormented with fire and brimstone in the presence of the holy angels, and in the presence of the Lamb: 11And the smoke of their torment ascendeth up for ever and ever: and they have no rest day nor night, who worship the beast and his image, and whosoever receiveth the mark of his name. 12Here is the patience of the saints: here are they that keep the commandments of God, and the faith of Jesus.

Ecclesiastes 12:13 Let us hear the conclusion of the whole matter: Fear God, and keep his commandments: for this is the whole duty of man.14For God shall bring every work into judgment, with every secret thing, whether it be good, or whether it be evil.

Universality and Cosmology

ANALYZING UNDERLYING IMPETUSES AS REFLECTED IN HISTORY (1840's-present)
Religion Civil Rights Science and Technology Space Forms of government Wars and conflicts
Crimes against humanity Literature Entertainment

Universitarianism reflected in religions, military, and politics. (1800's) III

Showing posts with label Elements. Show all posts
Showing posts with label Elements. Show all posts

Saturday, October 23, 2010

Dmitri Mendeleev (periodic chart)(knowlege of elements)

Dmitri Mendeleev

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Dmitri Mendeleev

Dmitri Mendeleev in 1897
Born 8 February 1834(1834-02-08)
Verhnie Aremzyani, Russian Empire
Died 2 February 1907 (aged 72)
St. Petersburg, Russian Empire
Nationality Russian
Fields Chemistry, physics and adjacent fields
Alma mater Saint Petersburg University
Notable students Dmitri Konovalov, Valery Gemilian, Alexander Baykov
Known for Inventing the Periodic table of chemical elements
Dmitri Ivanovich Mendeleev (also romanized Mendeleyev or Mendeleef; Russian: Дми́трий Ива́нович Менделе́ев About this sound listen ) (8 February [O.S. 27 January] 1834 – 2 February [O.S. 20 January] 1907), was a Russian chemist and inventor. He is credited as being the creator of the first version of the periodic table of elements. Using the table, he predicted the properties of elements yet to be discovered.

Contents

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Life

Mendeleev was born in Verhnie Aremzyani village, near Tobolsk, to Ivan Pavlovich Mendeleev and Maria Dmitrievna Mendeleeva (née Kornilieva). His grandfather was Pavel Maximovich Sokolov, a priest of the Russian Orthodox Church from the Tver region.[1] Ivan, along with his brothers and sisters, obtained new family names while attending the theological seminary.[2]
Mendeleev is thought to be the youngest of 14 siblings, but the exact number differs among sources.[3] At the age of 13, after the passing of his father and the destruction of his mother's factory by fire, Mendeleev attended the Gymnasium in Tobolsk.
In 1849, the now poor Mendeleev family relocated to Saint Petersburg, where he entered the Main Pedagogical Institute in 1850. After graduation, tuberculosis caused him to move to the Crimean Peninsula on the northern coast of the Black Sea in 1855. While there he became a science master of the Simferopol gymnasium №1. He returned with fully restored health to Saint Petersburg in 1857.
Between 1859 and 1861, he worked on the capillarity of liquids and the workings of the spectroscope in Heidelberg. In late August 1861 he wrote his first book on the spectroscope. On 4 April 1862 he had got engaged to Feozva Nikitichna Leshcheva, and they married on 27 April 1862 at Nikolaev Engineering College's church in Saint Petersburg.[4] Mendeleev became Professor of Chemistry at the Saint Petersburg Technological Institute and Saint Petersburg State University in 1863. In 1865 he became Doctor of Science for his dissertation "On the Combinations of Water with Alcohol". He achieved tenure in 1867, and by 1871 had transformed Saint Petersburg into an internationally recognized center for chemistry research. In 1876, he became obsessed with Anna Ivanova Popova and began courting her; in 1881 he proposed to her and threatened suicide if she refused. His divorce from Leshcheva was finalized one month after he had married Popova (on 2 April[5]) in early 1882. Even after the divorce, Mendeleev was technically a bigamist; the Russian Orthodox Church required at least 7 years before lawful re-marriage. His divorce and the surrounding controversy contributed to his failure to be admitted to the Russian Academy of Sciences (despite his international fame by that time). His daughter from his second marriage, Lyubov, became the wife of the famous Russian poet Alexander Blok. His other children were son Vladimir (a sailor, he took part in the notable Eastern journey of Nicholas II) and daughter Olga, from his first marriage to Feozva, and son Ivan and a pair of twins from Anna.
Though Mendeleev was widely honored by scientific organizations all over Europe, including the Copley Medal from the Royal Society of London, he resigned from Saint Petersburg University on 17 August 1890.
In 1893, he was appointed Director of the Bureau of Weights and Measures. It was in this role that he was directed to formulate new state standards for the production of vodka. As a result of his work, in 1894 new standards for vodka were introduced into Russian law and all vodka had to be produced at 40% alcohol by volume.[6]
Mendeleev also investigated the composition of oil fields, and helped to found the first oil refinery in Russia.
In 1905, Mendeleev was elected a member of the Royal Swedish Academy of Sciences. The following year the Nobel Committee for Chemistry recommended to the Swedish Academy to award the Nobel Prize in Chemistry for 1906 to Mendeleev for his discovery of the periodic system. The Chemistry Section of the Swedish Academy supported this recommendation. The Academy was then supposed to approve the Committee choice as it has done in almost every case. Unexpectedly, at the full meeting of the Academy, a dissenting member of the Nobel Committee, Peter Klason, proposed the candidacy of Henri Moissan whom he favored. Svante Arrhenius, although not a member of the Nobel Committee for Chemistry, had a great deal of influence in the Academy and also pressed for the rejection of Mendeleev, arguing that the periodic system was too old to acknowledge its discovery in 1906. According to the contemporaries, Arrhenius was motivated by the grudge he held against Mendeleev for his critique of Arrhenius's dissociation theory. After heated arguments, the majority of the Academy voted for Moissan. The attempts to nominate Mendeleev in 1907 were again frustrated by the absolute opposition of Arrhenius.[7]
In 1907, Mendeleev died at the age of 72 in Saint Petersburg from influenza. The crater Mendeleev on the Moon, as well as element number 101, the radioactive mendelevium, are named after him.

Periodic Table


Mendeleev's 1869 periodic table

Sculpture in honor of Mendeleev and the periodic table, located in Bratislava, Slovakia

Sculpture in Saint Petersburg
Other scientists had suggested in the 1860s that the elements display periodicity. John Newlands published his Law of Octaves in 1865. The lack of spaces for undiscovered elements and the placing of two elements in one box were criticized and his ideas were not accepted. Another was Lothar Meyer, who published a paper in 1864 describing 28 elements. Neither attempted to predict new elements. In 1863 there were 56 known elements with a new element being discovered at a rate of approximately one per year.
After becoming a teacher, Mendeleev wrote the definitive two-volume textbook at that time: Principles of Chemistry (1868–1870). As he attempted to classify the elements according to their chemical properties, he noticed patterns that led him to postulate his Periodic Table. Mendeleev was unaware of the other work on periodic tables going on in the 1860s. He made the following table, and by adding additional elements following this pattern, developed his extended version of the periodic table.[8][9]
Cl 35.5 K 39 Ca 40
Br 80 Rb 85 Sr 88
I 127 Cs 133 Ba 137
On 6 March 1869, Mendeleev made a formal presentation to the Russian Chemical Society, entitled The Dependence between the Properties of the Atomic Weights of the Elements, which described elements according to both atomic weight and valence. This presentation stated that
  1. The elements, if arranged according to their atomic weight, exhibit an apparent periodicity of properties.
  2. Elements which are similar in regards to their chemical properties have atomic weights which are either of nearly the same value (e.g., Pt, Ir, Os) or which increase regularly (e.g., K, Rb, Cs).
  3. The arrangement of the elements in groups of elements in the order of their atomic weights corresponds to their so-called valencies, as well as, to some extent, to their distinctive chemical properties; as is apparent among other series in that of Li, Be, B, C, N, O, and F.
  4. The elements which are the most widely diffused have small atomic weights.
  5. The magnitude of the atomic weight determines the character of the element, just as the magnitude of the molecule determines the character of a compound body.
  6. We must expect the discovery of many yet unknown elements–for example, two elements, analogous to aluminium and silicon, whose atomic weights would be between 65 and 75.
  7. The atomic weight of an element may sometimes be amended by a knowledge of those of its contiguous elements. Thus the atomic weight of tellurium must lie between 123 and 126, and cannot be 128. Here Mendeleev seems to be wrong as the "atomic mass" of tellurium (127.6) remains higher than that of iodine (126.9) as displayed on modern periodic tables, but this is due to the way atomic masses are calculated, based on a weighted average of all of an element's common isotopes, not just the one-to-one proton/neutron-ratio version of the element to which Mendeleev was referring.
  8. Certain characteristic properties of elements can be foretold from their atomic weights.
Mendeleev published his periodic table of all known elements and predicted several new elements to complete the table. Only a few months after, Meyer published a virtually identical table. Some consider Meyer and Mendeleev the co-creators of the periodic table, but virtually everybody agrees that Mendeleev's accurate prediction of the qualities of what he called ekasilicon, ekaaluminium and ekaboron (germanium, gallium and scandium, respectively) qualifies him for the majority of the credit for the table.
For his predicted eight elements, he used the prefixes of eka, dvi, and tri (Sanskrit one, two, three) in their naming. Mendeleev questioned some of the currently accepted atomic weights (they could be measured only with a relatively low accuracy at that time), pointing out that they did not correspond to those suggested by his Periodic Law. He noted that tellurium has a higher atomic weight than iodine, but he placed them in the right order, incorrectly predicting that the accepted atomic weights at the time were at fault. He was puzzled about where to put the known lanthanides, and predicted the existence of another row to the table which were the actinides which were some of the heaviest in atomic mass. Some people dismissed Mendeleev for predicting that there would be more elements, but he was proven to be correct when Ga (gallium) and Ge (germanium) were found in 1875 and 1886 respectively, fitting perfectly into the two missing spaces.[10]
By giving Sanskrit names to his "missing" elements, Mendeleev showed his appreciation and debt to the Sanskrit grammarians of ancient India, who had created sophisticated theories of language based on their discovery of the two-dimensional patterns in basic sounds. According to Professor Paul Kiparsky of Stanford University, Mendeleev was a friend and colleague of the Sanskritist Böhtlingk, who was preparing the second edition of his book on Pāṇini[11] at about this time, and Mendeleev wished to honor Pāṇini with his nomenclature.[12] Noting that there are striking similarities between the Periodic Table and the introductory Śiva Sūtras in Pāṇini's grammar, Prof. Kiparsky says:
[T]he analogies between the two systems are striking. Just as Panini found that the phonological patterning of sounds in the language is a function of their articulatory properties, so Mendeleev found that the chemical properties of elements are a function of their atomic weights. Like Panini, Mendeleev arrived at his discovery through a search for the "grammar" of the elements...[13]

Other achievements

Mendeleev made other important contributions to chemistry. The Russian chemist and science historian L.A. Tchugayev has characterized him as "a chemist of genius, first-class physicist, a fruitful researcher in the fields of hydrodynamics, meteorology, geology, certain branches of chemical technology (explosives, petroleum, and fuels, for example) and other disciplines adjacent to chemistry and physics, a thorough expert of chemical industry and industry in general, and an original thinker in the field of economy." Mendeleev was one of the founders, in 1869, of the Russian Chemical Society. He worked on the theory and practice of protectionist trade and on agriculture.
In an attempt at a chemical conception of the Aether, he put forward a hypothesis that there existed two inert chemical elements of lesser atomic weight than hydrogen. Of these two proposed elements, he thought the lighter to be an all-penetrating, all-pervasive gas, and the slightly heavier one to be a proposed element, coronium.
Mendeleev devoted much study and made important contributions to the determination of the nature of such indefinite compounds as solutions.

Mendeleev Medal
In another department of physical chemistry, he investigated the expansion of liquids with heat, and devised a formula similar to Gay-Lussac's law of the uniformity of the expansion of gases, while in 1861 he anticipated Thomas Andrews' conception of the critical temperature of gases by defining the absolute boiling-point of a substance as the temperature at which cohesion and heat of vaporization become equal to zero and the liquid changes to vapor, irrespective of the pressure and volume.
Mendeleev is given credit for the introduction of the metric system to the Russian Empire.
He invented pyrocollodion, a kind of smokeless powder based on nitrocellulose. This work had been commissioned by the Russian Navy, which however did not adopt its use. In 1892 Mendeleev organized its manufacture.
Mendeleev studied petroleum origin and concluded hydrocarbons are abiogenic and form deep within the earth - see Abiogenic petroleum origin. He wrote: "The capital fact to note is that petroleum was born in the depths of the earth, and it is only there that we must seek its origin." (Dmitri Mendeleev, 1877)[14]

See also

Mendeleev's predicted element

Friday, October 15, 2010

Arsenic poisoning [can cause arsenic skin lesions]

Arsenic poisoning

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Arsenic Poisoning
Classification and external resources
ICD-10 T57.0
ICD-9 985.1
eMedicine emerg/42
MeSH D020261
Arsenic Poisoning interferes with cellular longevity by allosteric inhibition of an essential metabolic enzyme pyruvate dehydrogenase (PDH) complex which catalyzes the oxidation of pyruvate to acetyl-CoA by NAD+. With the enzyme inhibited, the energy system of the cell is disrupted resulting in a cellular apoptosis episode. Biochemically, arsenic prevents use of thiamine resulting in a clinical picture resembling thiamine deficiency. Poisoning with arsenic can raise lactate levels and lead to lactic acidosis. Low potassium levels in the blood increase the risk of experiencing a life-threatening heart rhythm problem from arsenic trioxide. Arsenic in cells clearly stimulates the production of hydrogen peroxide (H2O2). When the H2O2 reacts with certain metals such as iron or manganese it produces a highly reactive hydroxyl radical. Inorganic Arsenic trioxide found in ground water particularly affects voltage-gated potassium channels,[1] disrupting cellular electrolytic function resulting in neurological disturbances, cardiovascular episodes such as prolonged qt interval, neutropenia, high blood pressure,[2] central nervous system dysfunction, anemia, Leukemia,[3] and death. Arsenic trioxide is a ubiquitous molecule present in American drinking water.[4]
“ Arsenic exposure plays a key role in the pathogenesis of vascular endothelial dysfunction as it inactivates endothelial nitric oxide synthase, leading to reduction in the generation and bioavailability of nitric oxide. In addition, the chronic arsenic exposure induces high oxidative stress, which may affect the structure and function of cardiovascular system. Further, the arsenic exposure has been noted to induce atherosclerosis by increasing the platelet aggregation and reducing fibrinolysis. Moreover, arsenic exposure may cause arrhythmia by increasing the QT interval and accelerating the cellular calcium overload. The chronic exposure to arsenic upregulates the expression of tumor necrosis factor-α, interleukin-1, vascular cell adhesion molecule and vascular endothelial growth factor to induce cardiovascular pathogenesis. ”
—Pitchai Balakumar1 and Jagdeep Kaur, "Arsenic Exposure and Cardiovascular Disorders: An Overview", Cardiovascular Toxicology, December 2009[5]

Contents

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[edit] Toxicity

Research has shown that the inorganic arsenites (trivalent forms) in drinking water have a much higher acute toxicity than organic arsenates (pentavalent forms).[6] The acute minimal lethal dose of arsenic in adults is estimated to be 70 to 200 mg or 1 mg/kg/day.[7] Most reported arsenic poisonings are caused by one of arsenic's compounds, also found in drinking water, arsenic trioxide which is 500 times more toxic than pure arsenic.
Arsenic is related to the first five leading causes of non-accidental death in the United States, bringing the total to 1,525,675 related mortalities. EPA efforts are underway to reduce drinking water exposure to zero.[8][9] heart disease[10] (hypertension related cardiovascular), cancer,[11] stroke[12] (cerebrovascular diseases), chronic lower respiratory diseases,[13] and diabetes. These diseases are all related to the alteration of voltage dependent potassium channels. Researchers, led by Ana Navas-Acien, MD, PhD, of the Johns Hopkins Bloomberg School of Health, studied 788 adults who had their urine tested for arsenic exposure in the 2003-2004 National Health and Nutrition Examination Survey. Participants with type 2 diabetes had a 26% higher level of total arsenic in their urine than those without the disease.[citation needed] Diabetes is also related to alteration of voltage dependent potassium channels due in part to the function of insulin and potassium in the cellular metabolism of glucose. Due to the regular appearance of arsenic in public drinking water supplies, it is likely that arsenic plays a part in about thirty percent of total all cause mortality in the United States.[citation needed] Arsenic prevalence in the water has been related to the occurrence of hypertension, erectile dysfunction and related conditions. Leading causes of mortality in the world are all related to arsenic. These are
Chronic exposure to inorganic arsenic may lead to hypertension, involuntary muscular dysfunction (including incontinence), diabetes, neuropathy, depression, obesity and any other condition related to the altered role of intercellular voltage-dependent potassium channels, including cutaneous hyperpigmentation.[14]:859

[edit] Symptoms of Arsenic Poisoning

Symptoms of arsenic poisoning begin with headaches, confusion and drowsiness. As the poisoning develops, convulsions and changes in fingernail pigmentation may occur. When the poisoning becomes acute, symptoms may include diarrhea, vomiting, blood in the urine, cramping muscles, hair loss, stomach pain, and more convulsions. The organs of the body that are usually affected by arsenic poisoning are the lungs, skin, kidneys, and liver. The final result of arsenic poisoning is coma or death.

[edit] Pathophysiology

Tissue culture studies have shown that arsenic blocks both IKr and Iks channels and, at the same time, activates IK-ATP channels. Arsenic also disrupts ATP production through several mechanisms. At the level of the citric acid cycle, arsenic inhibits pyruvate dehydrogenase and by competing with phosphate it uncouples oxidative phosphorylation, thus inhibiting energy-linked reduction of NAD+, mitochondrial respiration, and ATP synthesis. Hydrogen peroxide production is also increased, which might form reactive oxygen species and oxidative stress. These metabolic interferences lead to death from multi-system organ failure, probably from necrotic cell death, not apoptosis. A post mortem reveals brick red colored mucosa, due to severe hemorrhage. Although arsenic causes toxicity, it can also play a protective role.[15]

[edit] Diagnosis

There are tests available to diagnose poisoning by measuring arsenic in blood, urine, hair, and fingernails. The urine test is the most reliable test for arsenic exposure within the last few days. Urine testing needs to be done within 24–48 hours for an accurate analysis of an acute exposure. Tests on hair and fingernails can measure exposure to high levels of arsenic over the past 6–12 months. These tests can determine if one has been exposed to above-average levels of arsenic. They cannot predict, however, whether the arsenic levels in the body will affect health.[16]
Hair is a potential bioindicator for arsenic exposure due to its ability to store trace elements from blood. Incorporated elements maintain their position during growth of hair. Thus for a temporal estimation of exposure, an assay of hair composition needs to be carried out with a single hair which is not possible with older techniques requiring homogenization and dissolution of several strands of hair. This type of biomonitoring has been achieved with newer microanalytical techniques like Synchroton radiation based X ray fluorescence (SXRF) spectroscopy and Microparticle induced X ray emission (PIXE).The highly focused and intense beams study small spots on biological samples allowing analysis to micro level along with the chemical speciation. In a study, this method has been used to follow arsenic level before, during and after treatment with Arsenious oxide in patients with Acute Promyelocytic Leukemia.[17]

[edit] Treatment

Chemical and synthetic methods are now used to treat arsenic poisoning. Dimercaprol and dimercaptosuccinic acid are chelating agents which sequester the arsenic away from blood proteins and are used in treating acute arsenic poisoning. The most important side effect is hypertension. Dimercaprol is considerably more toxic than succimer.[18]
In the journal Food and Chemical Toxicology, Keya Chaudhuri of the Indian Institute of Chemical Biology in Kolkata, and her colleagues reported giving rats daily doses of arsenic in their water, in levels equivalent to those found in groundwater in Bangladesh and West Bengal. Those rats which were also fed garlic extracts had 40 percent less arsenic in their blood and liver, and passed 45 percent more arsenic in their urine. The conclusion is that sulfur-containing substances in garlic scavenge arsenic from tissues and blood. The presentation concludes that people in areas at risk of arsenic contamination in the water supply should eat one to three cloves of garlic per day as a preventative.[19][20][21]

Lead poisoning

Lead poisoning

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Jump to: navigation, search
Lead poisoning
Classification and external resources

An X ray demonstrating the characteristic finding of lead poisoning, dense metaphyseal lines.
ICD-10 T56.0
ICD-9 984.9
DiseasesDB 7307
MedlinePlus 002473
eMedicine article/815399
MeSH D007855
Lead poisoning (also known as plumbism, colica Pictonum, saturnism, Devon colic, or painter's colic) is a medical condition caused by increased levels of the heavy metal lead in the body. Lead interferes with a variety of body processes and is toxic to many organs and tissues including the heart, bones, intestines, kidneys, and reproductive and nervous systems. It interferes with the development of the nervous system and is therefore particularly toxic to children, causing potentially permanent learning and behavior disorders. Symptoms include abdominal pain, headache, anemia, irritability, and in severe cases seizures, coma, and death.
Routes of exposure to lead include contaminated air, water, soil, food, and consumer products. Occupational exposure is a common cause of lead poisoning in adults. One of the largest threats to children is lead paint that exists in many homes, especially older ones; thus children in older housing with chipping paint are at greater risk. Prevention of lead exposure can range from individual efforts (e.g. removing lead-containing items such as piping or blinds from the home) to nationwide policies (e.g. laws that ban lead in products or reduce allowable levels in water or soil).
Elevated lead in the body can be detected by the presence of changes in blood cells visible with a microscope and dense lines in the bones of children seen on X-ray. However, the main tool for diagnosis is measurement of the blood lead level; different treatments are used depending on this level. The major treatments are removal of the source of lead and chelation therapy (administration of agents that bind lead so it can be excreted).
Humans have been mining and using this heavy metal for thousands of years, poisoning themselves in the process. Although lead poisoning is one of the oldest known work and environmental hazards, the modern understanding of the small amount of lead necessary to cause harm did not come about until the latter half of the 20th century. No safe threshold for lead exposure has been discovered—that is, there is no known amount of lead that is too small to cause the body harm.

Contents

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[edit] Classification

Classically, "lead poisoning" or "lead intoxication" has been defined as exposure to high levels of lead typically associated with severe health effects.[1] Poisoning is a pattern of symptoms that occur with toxic effects from mid to high levels of exposure; toxicity is a wider spectrum of effects, including subclinical ones (those that do not cause symptoms).[2] However, professionals often use "lead poisoning" and "lead toxicity" interchangeably, and official sources do not always restrict the use of "lead poisoning" to refer only to symptomatic effects of lead.[2]
The amount of lead in the blood and tissues, as well as the time course of exposure, determine toxicity.[3][4] Diagnosis and treatment of lead exposure are based on blood lead level (the amount of lead in the blood), measured in micrograms of lead per deciliter of blood (μg/dL). The US Centers for Disease Control and Prevention and the World Health Organization state that a blood lead level of 10 μg/dL or above is a cause for concern; however, lead may impair development and have harmful health effects even at lower levels, and there is no known safe exposure level.[5][6] Authorities such as the American Academy of Pediatrics define lead poisoning as blood lead levels higher than 10 μg/dL.[7] Lead poisoning may be acute (from intense exposure of short duration) or chronic (from repeat low-level exposure over a prolonged period), but the latter is much more common.
Lead forms a variety of compounds and exists in the environment in various forms.[8] Features of poisoning differ depending on whether the agent is an organic compound (one that contains carbon), or an inorganic[9] Organic lead poisoning is now very rare, because countries across the world have phased out the use of organic lead compounds as gasoline additives, but such compounds are still used in industrial settings.[9]central nervous system[9] one. Organic lead compounds, which cross the skin and respiratory tract easily, affect the predominantly.

[edit] Signs and symptoms

Lead poisoning can cause a variety of symptoms and signs which vary depending on the individual and the duration of lead exposure.[10][11] Symptoms are nonspecific and may be subtle, and someone with elevated lead levels may have no symptoms.[12] Symptoms usually develop over weeks to months as lead builds up in the body during a chronic exposure, but acute symptoms from brief, intense exposures also occur.[13][14] Poisoning by organic lead compounds has symptoms predominantly in the central nervous system, such as insomnia, delirium, cognitive deficits, tremor, hallucinations, and convulsions.[9] Symptoms from exposure to organic lead, which is probably more toxic than inorganic lead due to its lipid solubility, occur rapidly.
Symptoms may be different in adults and children; the main symptoms in adults are headache, abdominal pain, memory loss, kidney failure, male reproductive problems, and weakness, pain, or tingling in the extremities.[15] The classic signs and symptoms in children are loss of appetite, abdominal pain, vomiting, weight loss, constipation, anemia, kidney failure, irritability, lethargy, learning disabilities, and behavior problems.[15] Children may also experience hearing loss, delayed growth, drowsiness, clumsiness, or loss of new abilities, especially speech skills.[12] Symptoms may appear in children at lower blood lead levels than in adults.[16]
Early symptoms of lead poisoning in adults are commonly nonspecific and include depression, loss of appetite, intermittent abdominal pain, nausea, diarrhea, constipation, and muscle pain.[17] Other early signs in adults include malaise, fatigue, decreased libido, and problems with sleep.[10] An unusual taste in the mouth and personality changes are also early signs.[18] In adults, symptoms can occur at levels above 40 μg/dL, but are more likely to occur only above 50–60 μg/dL.[10] Symptoms begin to appear in children generally at around 60 μg/dL.[19] However, the lead levels at which symptoms appear vary widely depending on unknown characteristics of each individual.[20] At blood lead levels between 25 and 60 μg/dL, neuropsychiatric effects such as delayed reaction times, irritability, and difficulty concentrating, as well as slowed motor nerve[21] Anemia may appear at blood lead levels higher than 50 μg/dL.[17] In adults, Abdominal colic, involving paroxysms of pain, may appear at blood lead levels greater than 80 μg/dL.[11] Signs that occur in adults at blood lead levels exceeding 100 μg/dL include wrist drop and foot drop, and signs of encephalopathy (a condition characterized by brain swelling), such as those that accompany increased pressure within the skull, delirium, coma, seizures, and headache.[22] In children, signs of encephalopathy such as bizarre behavior, discoordination, and apathy occur at lead levels exceeding 70 μg/dL.[22] For both adults and children, it is rare to be asymptomatic if blood lead levels exceed 100 μg/dL.[11] conduction and headache can occur.

[edit] Acute poisoning

In acute poisoning, typical neurological signs are pain, muscle weakness, paraesthesia, and, rarely, symptoms associated with encephalitis.[15] Abdominal pain, nausea, vomiting, diarrhea, and constipation are other acute symptoms.[23] Lead's effects on the mouth include astringency and a metallic taste.[23] Gastrointestinalconstipation, diarrhea, poor appetite, or weight loss, are common in acute poisoning. Absorption of large amounts of lead over a short time can cause shock (insufficient fluid in the circulatory system) due to loss of water from the gastrointestinal tract.[23] Hemolysis (the rupture of red blood cells) due to acute poisoning can cause anemia and hemoglobin in the urine.[23] Damage to kidneys can cause changes in urination such as decreased urine output.[23] People who survive acute poisoning often go on to display symptoms of chronic poisoning.[23] problems, such as

[edit] Chronic poisoning

Chronic poisoning usually presents with symptoms affecting multiple systems,[9] but is associated with three main types of symptoms: gastrointestinal, neuromuscular, and neurological.[15] Central nervous system and neuromuscular symptoms usually result from intense exposure, while gastrointestinal symptoms usually result from exposure over longer periods.[23] Signs of chronic exposure include loss of short-term memory or concentration, depression, nausea, abdominal pain, loss of coordination, and numbness and tingling in the extremities.[18] Fatigue, problems with sleep, headaches, stupor, slurred speech, and anemia are also found in chronic lead poisoning.[15] A "lead hue" of the skin with pallor is another feature.[24] A blue line along the gum, with bluish black edging to the teeth is another indication of chronic lead poisoning.[25] Children with chronic poisoning may refuse to play or may have hyperkinetic or aggressive behavior disorders.[15]

[edit] Exposure routes

Lead is a common environmental pollutant.[7] Causes of environmental contamination include industrial use of lead, such as is found in plants that process lead-acid batteries or produce lead wire or pipes, and metal recycling and foundries.[26] Children living near facilities that process lead, such as smelters, have been found to have unusually high blood lead levels.[27] In August 2009, parents rioted in China after lead poisoning was found in nearly 2000 children living near zinc and manganese smelters.[28] Lead exposure can occur from contact with lead in air, household dust, soil, water, and commercial products.[5]

By Years

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