Acute effects of diesel emission from the urea selective catalytic reduction engine system on male rats.
Short-term inhalation experiments were performed using Fischer 344 rats exposed to emission from the urea selective catalytic reduction (SCR) diesel engine system to identify health effects and compare them to those of the conventional diesel engine system. Rats were exposed to high-, middle-, or low-concentration emission (dilution ratio 1:29, 1:290, or 1:580) or clean air (control) for 1, 3, or 7 days (6 h/day), under driving conditions at a speed of 1320 rpm and a torque of 840 Nm. For the high-concentration group, the major components of the urea SCR emission were 0.04 mg/m(3) particulate matter (PM) and 0.78 ppm nitrogen dioxide (NO(2)); those of the conventional emission were 0.95 mg/m(3) PM and 0.31 ppm NO(2). The authors evaluated the respiratory effects of each emission on rats. Lymphocytes for 3-day exposure of both emissions significantly increased in bronchoalveolar lavage fluid, but there were slight differences. With an increase in potential antioxidant (PAO), 8-hydroxy-2'-deoxyguanosine for the urea SCR emission was significantly decreased, but that of the conventional emission was highest among all groups and did not show a response to PAO. In lungs, heme oxygenase (HO)-1 and tumor necrosis factor (TNF)-alpha mRNA expressions for the urea SCR emission showed a tendency to increase compared to those of the conventional emission. Thus, gene analysis results suggested that NO(2) from the urea SCR emission affected the expressions of mRNAs in lungs. However, as a whole, the results suggested that the health effects of the urea SCR emission might be less than the conventional emission on rats.
Tsukue
Naomi
N
Health Effects Research Group, Japan Automobile Research Institute, Tsukuba-city, Ibaraki, Japan. ntsukue@jari.or.jp
Kato
Atsunaka
A
Ito
Tsuyoshi
T
Sugiyama
Gen
G
Nakajima
Toru
T
D000080242:8-Hydroxy-2'-Deoxyguanosine; D000395:Air Pollutants, Occupational / Q000633:toxicity*; D000397:Air Pollution; D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology; D002384:Catalysis; D003849:Deoxyguanosine / Q000031:analogs & derivatives; D004229:Dithiothreitol / Q000737:chemistry; D008168:Lung / Q000378:metabolism / Q000473:pathology; D008297:Male; D009585:Nitrogen Dioxide / Q000032:analysis / Q000633:toxicity; D020411:Oligonucleotide Array Sequence Analysis; D009929:Organ Size / Q000187:drug effects; D010083:Oxidants, Photochemical / Q000032:analysis / Q000633:toxicity; D018384:Oxidative Stress / Q000187:drug effects; D052638:Particulate Matter / Q000032:analysis / Q000633:toxicity; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D011916:Rats, Inbred F344; D013439:Sulfhydryl Reagents / Q000737:chemistry; D014132:Trachea / Q000473:pathology; D014508:Urea / Q000737:chemistry*; D001335:Vehicle Emissions / Q000633:toxicity*; D015430:Weight Gain / Q000187:drug effects
D000395:Air Pollutants, Occupational; D010083:Oxidants, Photochemical; D052638:Particulate Matter; D012333:RNA, Messenger; D013439:Sulfhydryl Reagents; D001335:Vehicle Emissions; D000080242:8-Hydroxy-2'-Deoxyguanosine; D014508:Urea; D003849:Deoxyguanosine; D009585:Nitrogen Dioxide; D004229:Dithiothreitol