Inhalative intake

The inhalation RfD is derived from the NOAEL by applying uncertainty factors similar to those listed above for oral RfDs. A UF of 10 is used when e.Ktrapolating from animals to humans in addition to the calculation of the human equivalent dose, to account for interspecific variability in sensitivity to the to. icant. The resulting RfD value for inhalation c. posure is generally reported as a concentration in air in mg/m for continuous, 24 hour/day c. posurc, although it may be reported as a corresponding inhaled intake (in mg/kg-day). A human body weight of 70 kg and an inhalation rate of 20 nv /day are used to convert between an inhaled intake e.xprcsscd in units of mg/kg-day and a concentration in air e. pressed in mg/m. ... 

The model, as described in Durbin and Schmidt (1985), does not have an intake component, but it could be linked to either an oral or inhalation intake model to simulate the biokinetics of americium associated with such exposures. 

An annual inhalation intake by a 60-kg individual — in Bq/kg BW — that exceeds 0.67 232Th,... 

Contact area for oral and dermal pollutant intake, additional 0-2 cm in cases in which the inhalational intake is relevant... 

Two epidemiology studies have examined mortality among thorium workers neither found significant excess mortality. The standard mortality ratio (SMR) for all causes of death in a cohort of 3039 male workers in a thorium processing plant was 1.05 in comparison to United States white males (Polednak et al. 1983). The estimated radiation levels to the workers for inhalation intake ranged from 0.003-0.192 nCi/m (0.001-0.007 Bq/m ) for a period of 1-33 years. No evidence of overt industrial disease was found in a cohort of 84 workers at a thorium refinery exposed to <0.045-450 nCi/m (<0.002-0.02 Bq/m ) for <1-20 years (Albert et al. 1955). In both studies, the workers were exposed to other toxic compounds (uranium dust) as well as other radioactive materials (thoron, uranium daughters, thorium daughters, cerium). 

Because of their physiological property of concentrating primarily in bone and the low penetrating power of the a particle, internal deposition from ingestion and inhalation intakes are the most important exposure modes to man. Most of the actinides show low water solubilities and consequently drinking water typically will not dominate over diet with respect to ingestion. 

The human health risk assessment was conducted based on exposure estimates from two most relevant exposure pathways, namely dietary intake of POPs from food consumption and inhalation intake of airborne POPs contaminants. The potential intake of POPs from drinking water (considered to be a relatively minor exposure pathway) was not taken into account due to lack of relevant local data necessary for their estimation. 

When calculating the inhalation intake, dose coefficients and respiration intensity data (8100 m /year) for adults given in RSS-99 [6] were used. For lack of detailed data on relative concentrations of components in the inhaled air for specific NS and RC storage and basing meas, the appropriate recommendations of IAEA [7] were applied. 

Radionuclide Inhalation intake caused by marine aerosols External exposure ... 

Professiona 1 group Inhalation intake from marine aerosols External exposme Slun... 

An analysis of the calculation results shows that, if using the conservative approach (time of NS waterborne storage prior to dismantlement 5 years, that of storage after dismantlement 0 years), imder the taken assmnptions effective exposure doses would be approximately the same for all professional groups equaling 20 pSv/year. The main contribution to the exposure dose would be due to inhalation intake of radionuclides with marine aerosols. 

Such a transformation process will affect its mobility and increase its toxicity. This we can see in the corresponding data, reported in Table 1.2 [i.e., the carcinogenic potential or slope factor, the reference dose for oral and inhaled intake (RfD), its solubility, and its vapor pressure]. If these pollutants reach a certain exposure level for a community who breathes contaminated air or consumes polluted water, its members will be at risk. 

Illig, L., Paul, E.L., Eyer, R, Weger, H., and Bom, W., The treatment of psoriasis vulgaris with S-mustard-vaseline externally, taking especially into consideration the possible carcinogenic risk Ill-Communication. Clinical and experimental studies on the extent of percutaneous and inhalative intake of S-mustard-vasehne, Z. Hautkrankh., 54, 941, 1979. 

The body burden of bismuth is very low the daily oral intake of Bi, combined with inhalational intake, is estimated at 5-20 jg (Tsalev and Zaprianov 1983). Bismuth is one of the trace elements present in tissues, with relatively high levels being found in the nucleus ruber (Leonov 1956). Following its absorption, bismuth is found in all tissues, though no relationship between tissue concentration and therapeutic effect has yet been established. It is... 

Comparison of Daily Dietary and Inhalation Intake of Benzo [a] pyrene ... 

The following table lists, for workers, the annual limits on oral and inhalation intakes (ALl) for selected radionuclides based on the occupational radiation protection guidance of the International Commission on Radiological Protection (References 1 and 2). An intake of one ALI corresponds to an annual whole body dose of... 

Iodine is known to be extracted and concentrated in the thyroid gland for the purpose of hormone production. Inhalation intakes of iodine can occur through various mechanisms, leading to potential health risks, especially in the case of radioactive iodine, which when absorbed into the bloodstream may result in significant radiation dose to the respiratory tract and other organs. The major concern is the development of a thyroid carcinoma. 

Inhalation is a prominent pathway for radiation dose contributions from environmental or occupational intake of radioactive iodine. The ability to model and predict the kinetics of iodine in the body can be used for internal dosimetric assessments that predict the radiation dose delivered to various tissues. These assessments may be used to assess risk to the individual from inhalation intakes of radioactive iodine, which may occur through two distinct processes depending on its physical form. Iodine bound to particulates may be deposited in the respiratory tract, and iodine gas may be taken up by various tissues in the respiratory system during the breathing cycle. Inhalation models are necessary for estimates of iodine uptake and deposition that may result in radiation dose to workers or members of the public. 

Edible tissues from terrestrial animals, aquatic animals, and fowl are measured for radionuclide content to estimate the radiation dose to humans from food consumption. Organs and tissue that concentrate radionuclides, such as radioiodine in thyroids or radiostrontium in bones and teeth, are analyzed as indicators of such radionuclides in the environment. Domestic animals are sampled at the normal time of slaughter. Wildlife samples can be obtained from hunters or by special collections. Because radionuclide concentrations in animal tissues vary widely, depending on species, feed or inhalation intake, location, and individual metabolism, multiple animals must be sampled to establish a normal range of radionuclide concentrations. Radionuclides that emit gamma rays can be measured in live animals by a technique similar to whole-body counting in humans. 

Kawamura (1987) estimated the plutonium-239, -240 inhalation intake of visitors to Kiev after the Chernobyl accident to be 0.8 pCi/day (0.03 Bq/day) during peak fallout exposure. 

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