摘要:

AbstractEpidemiological and animal toxicological studies have indicated that reactions between SO2(g) and metal containing aerosols result in the formation of respiratory irritants. It had initially been suggested by EPA that sulfate per se was responsible for the observed health effects. That now appears unlikely. These studies point out the importance of understanding in detail the chemical species formed by such interactions. In the present paper procedures which have been used to study the formation of aerosol inorganic S(IV) species are described, together with the results obtained from studies in the flue line, workroom, and plume of smelters.Both atmospheric and laboratory studies indicate that very stable complexes of S(IV) with Fe(III) or Cu(?) can form in aerosols. The data suggest that the concentration of these S(IV) complexes in primary particulate emissions from smelters will be about 10% of the sulfate concentration. In plumes the concentration of inorganic S(IV) varied from 10 to 80% of the sulfate concentration. The most important variable controlling the formation of these S(IV) complexes in a plume aerosol droplet is the aerosol acidity. The formation of aerosol inorganic S(IV) complexes in the plume is not related to the formation of sulfate.There have been no studies previously reported that would allow an unequivocal evaluation of the toxicological implications of the chemistry reviewed in this paper. If these various S(IV) species are responsible at the low concentrations reported here for the “synergistic” effects previously reported between SO2(g) and aerosols, then additional toxicological work would appear warran

ISSN:0271-3586    

DOI:10.1002/ajim.4700010322

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

摘要:

AbstractWe hypothesize that gaseous ammonia (NH3) released into respiratory airways can neutralize inhaled acidic particles and alter or mitigate their toxicity. To test this hypothesis, we have examined the relationship between respiratory NH3and the chemical neutralization of inhaled sulfuric acid (H2SO4) aerosol in the surgically isolated upper airways of anesthetized dogs.With air entering via the mouth, the NH3concentration measured at the larynx, ranged between 30 and 225 parts per billion (ppb). The extent of neutralization at this point ranged from 8%‐70% (n = 16) for the 0.5‐μm particles and 7%‐22% (n = 6) for the 1.0‐μm particles. With air entering via the nose, the laryngeal NH3concentration ranged between 50 and 220 ppb. Neutralization values were between 15%‐65% (n = 8) for 0.5‐μm particles, and between 16%‐18% (n = 3) for 1.0‐μm particles. For both routes of entry, the extent of neutralization was correlated with the laryngeal NH3concentration. We conclude that the chemistry of acidic particles is significantly altered by respiratory NH3during inhalation. The extent of neutralization is related to both the NH3concentration in the airway and the size of the particle entering the airway. The extent of neutralization per ppb of laryngeal NH3is related to the route of entry, being greater for the

ISSN:0271-3586    

DOI:10.1002/ajim.4700010323

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

ISSN:0271-3586    

DOI:10.1002/ajim.4700010324

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

ISSN:0271-3586    

DOI:10.1002/ajim.4700010325

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY

ISSN:0271-3586    

DOI:10.1002/ajim.4700010301

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1980

数据来源: WILEY