No abstract

No abstract

No abstract

Employees who had experienced work related symptoms from the skin or airways during the most recent five year period were identified through interviews with the company physicians and nurses, the management representatives, and the trade union occupational safety officers. We visited all the dying, weighing, and laboratory departments and interviewed all staff on duty that day. Symptomatic subjects not present at the day of the visit (for

An estimated 500 million vehicles worldwide are equipped with an exhaust catalyst that uses platinum group elements (PGE) as the main active components and thus contribute to global PGE emissions. Although PGE emitted from automobile exhaust catalysts were first believed to remain in the roadside environment, we propose here that fine PGE-containing particles in automobile exhaust have resulted in a widespread distribution of emitted PGE. Regional and long-range transport of PGE from automobile exhaust catalysts is supported by elevated PGE deposition in both a peat bog located 250 m from traffic and in central Greenland, respectively. Russian smelters were also found to contribute to PGE contamination in central Greenland. Deposition rates estimated for the roadside environment, the peat bog, and central Greenland were used to provide a first estimate of PGE deposition in the northern hemisphere. The results show that deposition of regionally or long-range transported PGE accounts for a large fraction of total PGE deposition, and PGE deposition in the roadside environment represents less than 5% of the total deposition. Transport at the regional and global scales represents an important component in the environmental cycle of emitted PGE and needs to be further studied to fully assess the environmental fate of PGE from automobile exhaust catalysts.

No abstract

Objectives-To evaluate the eYciency of diVerent automotive cabin air filters to prevent penetration of components of diesel exhaust and thereby reduce biomedical eVects in human subjects. Filtered air and unfiltered diluted diesel exhaust (DDE) were used as negative and positive controls, respectively, and were compared with exposure to DDE filtered with four diVerent filter systems. Methods-32 Healthy non-smoking subjects (age 21-53) participated in the study. Each subject was exposed six times for 1 hour in a specially designed exposure chamber: once to air, once to unfiltered DDE, and once to DDE filtered with the four diVerent cabin air filters. Particle concentrations during exposure to unfiltered DDE were kept at 300 µg/m 3 . Two of the filters were particle filters. The other two were particle filters combined with active charcoal filters that might reduce certain gaseous components. Subjective symptoms were recorded and nasal airway lavage (NAL), acoustic rhinometry, and lung function measurements were performed. Results-The two particle filters decreased the concentrations of diesel exhaust particles by about half, but did not reduce the intensity of symptoms induced by exhaust. The combination of active charcoal filters and a particle filter significantly reduced the symptoms and discomfort caused by the diesel exhaust. The most noticable diVerences in eYcacy between the filters were found in the reduction of detection of an unpleasant smell from the diesel exhaust. In this respect even the two charcoal filter combinations diVered significantly. The eYcacy to reduce symptoms may depend on the abilities of the filters investigated to reduce certain hydrocarbons. No acute eVects on NAL, rhinometry, and lung function variables were found. Conclusions-This study has shown that the use of active charcoal filters, and a particle filter, clearly reduced the intensity of symptoms induced by diesel exhaust. Complementary studies on vehicle cabin air filters may result in further diminishing the biomedical eVects of diesel exhaust in subjects exposed in traYc and workplaces. (Occup Environ Med 1999;56:222-231)

No abstract