Inhalatory Exposure

Most of the Al absorbed from the respiratory tract accumulates in the lungs. Pulmonary lesions have been described in employees of Al processing or manufacturing industries and encephalopathy after Al inhalation has been reported. Al is widely distributed and has many industrial uses, and toxicity from occupational exposure is assumed to be extremely rare [2, 177]. Nevertheless, a recent study investigating adverse effects on the central nervous system of Al welders found an Al-exposure-related increase in blood and urine Al concentrations, deficits in neuropsychological test performance and mild diffuse EEG abnormalities. Therefore, the potential for Al-induced neurotoxicity in those occupationally exposed to Al fumes may be greater than previously suspected [177]. 

Aerosol antiperspirants can be absorbed systematically via the lungs and airways and through the nasal-olfactory route. There is as yet insufficient information available to determine the possibility of Al accumulation in the brain [178]. 

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Rydzinski, K., Korsak, Z., JedlinSca, U. Sokal, J.A. (1992) The toxic effects of combined exposure to toluene and m-xylene in animals. IV. Liver ultrastructure after subchronic inhalatory exposure. Pol. J. occup. Med. environ. Health, 5, 35-42... 

Some agrichemicals may cause toxic pneumonitis after non-inhalatory exposure. The best known of these agents is the herbicide paraquat, which exerts a selective toxicity for the pulmonary epithelium... 

SCAN concluded on user safety that the main risk from semduramycin was from inhalatory exposure. Acute inhalation toxicity was high (rat LC50 67mgm ), but dusting was minimised by an antidust formulation for the additive. It was nevertheless recommended that workers should use a dust mask. 

In a review. Arts and Kuper (2007) have summarized the animal test methods, which have been used to detect immune-mediated respiratory disease. The tests for respiratory sensitization include dermal as well as inhalatory or topical exposure of mice, rats, or guinea pigs for induction and challenge, and may measure various endpoints to evaluate respiratory sensitization. The review concludes that standardized and validated dose-response test methods are urgently required in order to allow identification of respiratory allergens and to make it possible to recommend safe exposure levels for consumers and workers. 

A concentration-time correction is needed if the duration of exposure used to determine the inhalatory dose descriptor differs from that of the inhalatory DNEL to be established. For example, the dose descriptor of a prenatal developmental toxicity study by inhalation applies to a daily exposure time of 6 h. However, inhalatory DNELs for workers and consumers usually refer to 8 h and up to 24 h per day, respectively. Therefore, the inhalatory dose descriptor needs to be modified in terms of a timescaling. 

It may occur that the exposure route of the dose descriptor does not correspond to the exposure route of the DNEL. Therefore, the dose descriptor needs to be corrected in terms of a route-to-route-extrapolation. For example, if an inhalatory dose descriptor (expressed in mg/m ) serves as starting point for the derivation of an oral DNEL (expressed in mg/kg body weight), the basal respiratory volume for the relevant species (e.g., in rats 1.15 mVkg body weight/24 h) is used to correct the dose descriptor in terms of the estimated total daily... 

Levels of di(2-ethylhexyl) phthalate ranging from < 1 to 4100 tg/mL [mg/L] in the condensate from water traps of six respirators have been reported. Estimation of the inhalatory di(2-ethylhexyl) phthalate exposure to five artificially ventilated preterm infants over a 24-h period yielded values ranging between 1 ig/h and 4200 tg/h. Di(2-... 

Small dusty interiors Exposure to food and inhalatory allergens... 

Feron VJ, Woutersen RA, Appelman LM. 1984. Epithelial damage and tumors of the nose after exposure to four different aldehydes by inhalation. BGA Schr 5(Probl Inhalatory Toxic Stud) 587-610. 

There is much dissimilarity between the fields of human and ecological risk assessment, but many of the differences are not typical for mixtures. Examples are differences in assessment endpoints (individuals vs. species or communities), in exposure routes and media (oral, inhalatory, and dermal for humans vs. aquatic or terrestrial for ecosystems), and in the level of mechanistic understanding (generally larger in human than in ecological studies). 

Pavanello et al. (1999) used the HPLC/fluorescence method to detect the anti -BPDE-DNA adduct in mononuclear leukocytes exposed to PAHs. The authors concluded that this methodology can be used for the evaluation of the chronic exposure to PAHs and that the inhalatory via contributed, substantially, for the adducts formation in the lymphoi de plus monocyte fraetion in eoal factories workers and chimney cleaners. 

For estimating the lung cancer risk assoeiated with inhalatory PAH exposures, the World Health Organization (WHO) has suggested a unit risk of 8.7x10 (pg/m ) for the lifetime (70 years) PAH exposure, assuming one was exposed to BaP concentration of 1 pg/m ... 

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