Pulmonary and cardiovascular effects of traffic-related particulate matter: 4-week exposure of rats to roadside and diesel engine exhaust particles.
Traffic-related particulate matter (PM) may play an important role in the development of adverse health effects, as documented extensively in acute toxicity studies. However, rather little is known about the impacts of prolonged exposure to PM. We hypothesized that long-term exposure to PM from traffic adversely affects the pulmonary and cardiovascular system through exacerbation of an inflammatory response. To examine this hypothesis, Fisher F344 rats, with a mild pulmonary inflammation at the onset of exposure, were exposed for 4 weeks, 5 days/week for 6 h a day to: (a) diluted diesel engine exhaust (PM(DEE)), or: (b) near roadside PM (PM(2.5)). Ultrafine particulates, which are largely present in diesel soot, may enter the systemic circulation and directly or indirectly trigger cardiovascular effects. Hence, we assessed the effects of traffic-related PM on pulmonary inflammation and activity of procoagulants, vascular function in arteries, and cytokine levels in the heart 24 h after termination of the exposures. No major adverse health effects of prolonged exposure to traffic-related PM were detected. However, some systemic effects due to PM(DEE) exposure occurred including decreased numbers of white blood cells and reduced von Willebrand factor protein in the circulation. In addition, lung tissue factor activity is reduced in conjunction with reduced lung tissue thrombin generation. To what extent these alterations contribute to thrombotic effects and vascular diseases remains to be established. In conclusion, prolonged exposure to traffic-related PM in healthy animals may not be detrimental due to various biological adaptive response mechanisms.
Environment and Safety Division, Centre for Environmental Health, National Institute for Public Health and the Environment, Bilthoven, The Netherlands. miriam.gerlofs@rivm.nl
Miriam E
ME
Gerlofs-Nijland
Annike I
AI
Totlandsdal
Evren
E
Kilinç
A John F
AJ
Boere
Paul H B
PH
Fokkens
Daan L A C
DL
Leseman
Constantinos
C
Sioutas
Per E
PE
Schwarze
Henri M
HM
Spronk
Patrick W F
PW
Hadoke
Mark R
MR
Miller
Flemming R
FR
Cassee
D000393:Air Pollutants / Q000633:toxicity; D000818:Animals; D002319:Cardiovascular System / Q000187:drug effects* / Q000378:metabolism; D018836:Inflammation Mediators / Q000633:toxicity; D019570:Inhalation Exposure / Q000009:adverse effects*; D008168:Lung / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D008297:Male; D010316:Particle Size; D052638:Particulate Matter / Q000633:toxicity*; D051381:Rats; D011916:Rats, Inbred F344; D013997:Time Factors; D001335:Vehicle Emissions / Q000633:toxicity*
D000393:Air Pollutants; D018836:Inflammation Mediators; D052638:Particulate Matter; D001335:Vehicle Emissions