Health, human respiratory system

No significant harmful health effects to humans or animals are expected from exposure to this pathogen unless the individual has a compromised respiratory system or suppressed immune system. Direct contact with large quantities of B. subtilis spores may cause redness or irritation of the skin. 

Intermediate-Duration Exposure.No studies are available on the adverse health effects from intermediate-duration exposure in humans by any route. Studies in animals indicate that exposure to endrin via inhalation can be lethal and causes effects on the nervous and respiratory systems, the liver, the brain, adrenals, and kidneys (Treon et al. 1955). Since systemic effects were observed at levels which caused death, data are not sufficient to derive an intermediate-duration inhalation MRL. Animal studies also demonstrate that oral intermediate-duration exposure can lead to death in several species (rat, mouse, hamster, rabbit, monkeys, cat) (Treon et al. 1955). Endrin was lethal in rabbits following dermal exposure (Treon et al. 1955). No other treatment-related disorders are known. Additional studies for oral and dermal routes using a range of exposure levels would be useful in identifying potential target tissues. 

Genetic alterations or abnormalities of germ cells, some of which can be caused by toxicant exposure, can be manifested by adverse effects on progeny. The important health effects of these kinds of alterations may be appreciated by considering the kinds of human maladies that are caused by inherited recessive mutations. One such disease is cystic fibrosis, in which the clinical phenotype has thick, dry mucus in the tubes of the respiratory system such that inhaled bacterial and fungal spores cannot be cleared from the system. This results in frequent, severe infections. It is the consequence of a faulty chloride transporter membrane protein that does not properly transport Cl ion from inside cells to the outside, where they normally retain water characteristic of healthy mucus. The faulty transporter protein is the result of a change of a single amino acid in the protein. 

Tungsten has no essential role in the health of plants, humans, or animals. In moderate amounts, it also presents virmally no health danger. Exposure to tungsten dust or fumes may cause mild irritation of the skin, eyes, and respiratory system. 

Furfural can cause skin sensitization and has been shown to cause irritant dermatitis which may become eczematous. It can be absorbed through the skin or by inhalation and it is an irritant to the eyes, skin, and respiratory system. No throat or eye irritation was noted in humans exposed to 10 ppm for 8h or 20 ppm for 4h. No data are available relative to reproductive or developmental effects in humans exposed to furfural. When air concentrations reach from 2 to 14 ppm, headaches, itching of the throat, and red/weeping eyes occurred in exposed humans. If exposures are severe, respiratory tract irritation can progress to acute respiratory distress syndrome, which may be delayed in its onset by up to 72 h. The National Institute for Occupational Safety and Flealth has indicated that 100 ppm in air is a concentration immediately dangerous to life or health. 

Acute NP exposure, such as may occur in occupational settings, can produce severe irritation to the eye, skin, and respiratory system. Symptoms of such acute toxicity include a burning sensation, cough, labored breathing, sore throat, unconsciousness, abdominal pain, diarrhea, nausea, skin irritation, and burns. Other than these acute effects, there is no conclusive evidence that typical exposure to NP causes adverse health effects in humans. 

The dominant route of human exposure to wood dusts is inhalation. In fact, most significant health effects seem to result from direct contact of the inhaled wood dusts with tissues of the respiratory tract. Because of the wide distribution of wood dust particle sizes, there is potential for deposition throughout the respiratory system. However, the majority deposit in the upper airways, primarily in the nose. This correlates well with observations that the most important health effects, such as upper respiratory symptoms and sino-nasal cancer, occur in the upper airways. While ingestion also is common, no adverse health effects were reported. Dermal contact also occurs routinely, occasionally causing dermatitis. 

As we have seen the morbidity cases of respiratory and alimentary systems highlight the inter-correlation between biogeochemical food web, pollution loading and human health. However, the physiological response of central nervous and cardiovascular systems to heavy metals and pesticides is also known and the relevant analysis of morbidity of cardiovascular system and psychological distresses was carried out in 1991-1997 in the industrial area of Crimea—Armyansk city, Ukraine (Evstafieva et al, 1999). The correlation between morbidity of a respiratory system and pollutants emissions was found (Figure 6). 

No MRLs were derived for inhalation exposure to selenium because of insufficient quantitative data concerning both human and animal exposures. Data on the health effects of inhaled selenium in humans are derived from studies of occupationally exposed workers. These studies suggest that the respiratory system is the most sensitive end point for inhaled selenium dust, but they do not provide quantitative measurements of exposure and are frequently confounded by concurrent exposure to other chemicals. Animal studies support the respiratory system as the target of selenium toxicity, but these are acute studies of exposure to high concentrations of selenium that also produced serious health effects and death. 

The adverse effects on human health due to smog include shortness of breath in those with compromised pulmonary function, and may include increased asthma frequencies in young children. Long-term exposure often permanently impairs human respiratory and immune system function, and can lead to death historical records indicate that 4000 Londoners died in December 1952 due to exposure to unsafe smog levels. 

The process of combustion of materials enriched with yttrium seems to be a risk factor as a source of flammable dusts. Yttrium oxide, yttrium chloride, yttrium citrate, and certain other yttrium compounds may cause chronic pathological effects in different parts of the mammalian respiratory system, according to the results of experimental studies carried out in rats, mice, guinea pigs, and rabbits. Therefore, a higher risk for human health may be... 

Dilute acetic acid in the form of vinegar is harmless and has been consumed by humans for centuries. Prolonged contact with the skin or eyes may, however, produce irritation of tissues and should be avoided. Concentrated forms of acetic acid pose more serious health risks, such as irritation of the gastrointestinal system, respiratory system, and eyes. Most people do not come into contact with the concentrated acid, and safety precautions are of importance only to individuals who handle the material in their work. 

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