Arsenic chronic exposure

Chronic exposure to arsenicals by way of the air, diet, and other routes has been associated with liver, kidney, and heart damage, hearing loss, brain-wave abnormalities, and impaired resistance to viral infections. 

Ng, J.C., A.A. Seawright, L. Qi, C.M. Garnett, M.R. Moore, and B. Chiswell. 1998. Tumours in mice induced by chronic exposure of high arsenic concentrations in drinking water. SEGH 3rd Inter. Conf. Arsenic Expos. Health Effects 28. 

Ingested arsenic localizes to the skin [2, 7], where it may alter cutaneous immune responses. The delayed type hypersensitivity (DTH) response to 2,4-dinitrochlorobenzene (DNCB) was suppressed in Bowen s disease patients [8], Langerhans cells (LC) in skin lesions and perilesioned skin from arsenic-induced Bowen s disease and carcinomas were reduced in number and were morphologically altered, having a notable loss of dendrites [9], These data suggest that chronic exposure to arsenic in drinking water may... 

Chronic Exposure Lewisite can cause sensitization and chronic lung impairment. Also, by comparison to agent mustard and arsenical compounds, it can be considered as a suspected human carcinogen. 

Inhaled arsine is oxidized to form elemental trivalent arsenic (As ) and arsenous oxide (AS2O3), two human carcinogens. Excess cancers from trivalent arsenic and arsenic trioxide have been associated with cumulative lifetime arsenic exposure. Exposure to arsine above 0.004ppm is associated with increased urinary arsenic excretion, indicating exposure to arsenic. Current exposure limits may not prevent potential chronic toxicity. ... 

Lung damage after chronic exposure to fumes in industry has not been described. The higher incidence of respiratory cancer reported in copper smelters is due to the presence of arsenic in the ore. ... 

The toxicity of chronic exposure to arsenic is well established and the best recommendation is to avoid arsenic exposure. The most common home exposure is from contaminated drinking water and arsenic-treated lumber. Certain areas of the country have higher levels of arsenic in water. The EPA has lowered arsenic drinking water standards, but water providers have until 2006 to meet the new standards. Avoid inhalation of sawdust from arsenic-treated lumber or inhalation of smoke from burning arsenic-treated wood. And of course always wash your hands. This is particularly important if a young child is playing on arsenic-treated wood. 

Chemically, arsenic is complex in that it can exist in a variety of forms including trivalent and pentavalent or as arsenic trioxide (computer chip manufacture) and arsenic acid. Arsenic is excreted in skin cells, sweat, hair, and fingernails, which can be seen as white transverse bands. Acute exposure to arsenic results in gastrointestinal pain, sensory loss, cardiovascular failure, and death. Chronic exposure or survival of acute exposure can cause loss of peripheral sensory function and loss of central nervous system function. Chronic arsenic exposure can also cause cancer of the lung and skin (see the chapter on arsenic). 

Conducting studies under controlled conditions with appropriate aquatic and terrestrial indicator organisms to determine the effects of chronic exposure to low doses of inorganic and organic arsenicals on reproduction, genetic makeup, adaptation, disease resistance, growth, and other variables... 

Many organ systems in the human body can be affected by chronic exposure to arsenic (Agency for Toxic Substances and Disease Registry (ATSDR), 2007 World Health Organization (WHO), 2001 National Research Council (NRC), 1999, 2001). These include the skin, developing fetus, liver and the cardiovascular, pulmonary, nervous, and endocrine systems. These effects are dose-related and primarily arise from oral exposure to arsenic, although inhalation of arsenic may also result in adverse health effects. The chronic effects from dermal exposure to arsenic are not known. 

Arsenic Toxicosis. Urine arsenic is the best indicator of current or recent exposure. Atomic absorption spectrophotometry is preferred as the detection method. Hair or fingernail sampling may also be helpful. Use of blood is useful if analyzed soon after exposure or in cases of continuous chronic exposure. After acute exposure, chelation therapy is instituted utilizing either (1) Dimercaprol BAL (British Anti-Lewisite) and analogues ... 

Chronic Exposure (Arsenic). Primarily symptomatic treatment is chosen. Chelation therapy is practiced, but its usefulness in cases of chronic exposure is still questionable. 

Both acute and chronic exposure to lead became more common with the advent of the Industrial Revolution and there were as many as a thousand cases per year of lead poisoning in the UK at the end of the nineteenth century. During the nineteenth century there were also many cases of lead poisoning due to contamination of domestic drinking water in areas such as the north of England where slightly acidic water was delivered to houses in lead pipes. Lead was also used in fungicides in the form of lead arsenate. 

Kojima, C., Qu, W., Waalkes, M.P., Himeno, S., Sakurai, T. (2006). Chronic exposure to methylated arsenicals stimulates arsenic excretion pathways and induces arsenic tolerance in rat liver cells. Toxicol. Sci. 91 70-81. 

Arsenic in aquatic environments is usually more concentrated in sediments and pore water than in the overlying water column (Ahmann et al., 1997 Smedley and Kinniburgh, 2002 Williams, 2001). The most abundant forms of arsenic are arsenate [As(V)] and arsenite [As(III)], but methylated forms can occur in mine-impacted environments (i.e., methylarsenic acid and dimethylarsenic acid) (Smedley and Kinniburgh, 2002) see Chapter 9.02. The principal pathway of arsenic toxicity is through dietary exposure to sediment and suspended particulates by fish, followed by human consumption. Environmental exposure to arsenic is a causal factor in human carcinogenous and other related health issues. Chronic exposure symptoms in humans include hyperkeratosis, hyperpigmentation, skin malignancies, and peripheral arteriosclerosis. Water provides the dominant pathway for arsenic exposure in humans (Williams, 2001). 

Antimony, which is considered a nonessential element, is comparable in its toxicological behavior to arsenic and bismuth. In analogy to arsenic, trivalent antimony compounds generally are more toxic than the pentavalent compounds. Poisoning with antimony and its compounds can result from acute and chronic exposure, especially from exposure to... 

Chronic exposure to silver produces a bluish skin discoloration known as argyria. Gold poisoning has resulted from the use of gold salts for treatment of arthritis. Poisoning from antimony, arsenic, bismuth, mercury, and thallium is well known. 

Acute inhalation exposure to elemental selenium dust, possibly including some selenium dioxide, in occupational settings has been shown to irritate mucous membranes in the nose and throat and produce coughing, nosebleed, loss of olfaction, and in heavily exposed workers, dyspnea, bronchial spasms, bronchitis, and chemical pneumonia (Clinton 1947 Hamilton 1949). Chronic exposure of 40 workers at a copper refinery produced increased nose irritation and sputum (Holness et al. 1989). The exact concentration of selenium was not given, but the concentration was reported to exceed 0.2 mg selenium/m3. Confounding variables in this study include concurrent exposure to several other metals including copper, nickel, silver, lead, arsenic, and tellurium. 

Liquid, bp 105°C. Said to be produced by the mould Penicillium brevicaule growing on wallpaper coloured green with arsenical green pigments. Causes chronic exposure to arsenic. 

Induction of cancer appears to be the most striking long-term effect of chronic exposure to inorganic arsenic. Epidemiological studies have demonstrated an evident causal relationship between environmental, occupational, and medicinal exposure of man to inorganic arsenic and cancer of the skin and lungs (NAS 1977, Fowler 1977, Leonard 1984, lARC 1987, Cantor 1997, Hayes 1997). 

Lung cancer is probably the most lethal manifestation of toxic effect from chronic exposure to certain chemicals. Asbestos fibers, coke oven emissions, arsenic, chromates, nickel and the radioactive gas, radon, are some of the substances known to cause lung cancer. For a detailed discussion of carcinogenesis, see Part A, Section VI, while specific compounds are discussed in Part B of this text. Acute and chronic effects of some common pulmonary toxicants are presented in Table V.3. 

Arsenic is absorbed into the body through a G1 route and inhalation. The acute symptoms include fever, G1 disturbances, irritation of the respiratory tract, ulceration of the nasal septum, and dermatitis. Chronic exposure can produce pigmentation of the skin, peripheral neuropathy, and degeneration of liver and kidneys. 

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