Particulate Air Pollution and Cardiovascular Risk: Short-term and Long-term Effects

The effect of acute and long-term exposures to outdoor particulate air pollution on lung function in healthy adults is not well established. The objective of this study was to conduct a systematic literature review and meta-analysis of studies that assessed the relationship of outdoor particulate air pollution and lung function in healthy adults. Studies that contained data on outdoor air particulate matter levels (PM10 or PM2.5) and forced expiratory volume in 1 s (FEV1) in healthy adults were eligible for inclusion. Effect estimates, in relation to long-term and acute exposures, were quantified separately using random effects models. A total of 27 effect estimates from 23 studies were included in this review. Acute exposures were typically assessed with PM2.5, while long-term exposures were predominantly represented by PM10. A 10 µg/m3 increase in short-term PM2.5 exposure (days) was associated with a −7.02 mL (95% CI −11.75 to –2.29) change in FEV1. A 10 µg/m3 difference in long-term PM10 exposure was associated with a −8.72 mL (95% CI −15.39 to –2.07) annual change in FEV1 and an absolute difference in FEV1 of −71.36 mL (95% CI −134.47 to –8.24). This study provides evidence that acute and long-term exposure to outdoor particulate air pollution are associated with decreased FEV1 in healthy adults. Residual confounding from other risk factors, such as smoking, may explain some of the effect for long-term exposures. More studies are required to determine the relationship of long-term exposure to PM2.5 and short-term exposure to PM10, which may have different biologic mechanisms.

Download Full-text

Air Pollution and Mortality: Timing Is Everything

Atmosphere ◽

10.3390/atmos11121274 ◽

2020 ◽

Vol 11 (12) ◽

pp. 1274

Author(s):

Frederick W. Lipfert

Keyword(s):

Air Pollution ◽

Time Series ◽

Air Quality ◽

Indoor Air Pollution ◽

Health Effect ◽

Traffic Density ◽

Long Term Effects ◽

Short Term ◽

Long Term Studies

This paper considers timing issues in health-effect exposure and response studies. Short-term studies must consider delayed and cumulative responses; prior exposures, disease latency, and cumulative impacts are required for long-term studies. Lacking individual data, long-term air quality describes locations, as do greenspaces and traffic density, rather than exposures of residents. Indoor air pollution can bias long-term exposures and effect estimates but short-term effects also respond to infiltrated outdoor air. Daily air quality fluctuations may affect the frail elderly and are necessarily included in long-term averages; any true long-term effects must be given by differences between annual and daily effects. I found such differences to be negligible after adjusting for insufficient lag effects in time-series studies and neglect of prior exposures in long-term studies. Aging of subjects under study implies cumulative exposures, but based on age-specific mortality, I found relative risks decreasing with age, precluding cumulative effects. A new type of time-series study found daily mortality of previously frail subjects to be associated with various pollutants without exposure thresholds, but the role of air pollution in the onset of frailty remains an unexplored issue. The importance of short-term fluctuations has been underestimated and putative effects of long-term exposures have been overestimated.

Download Full-text

Long-term effects of total and source-specific particulate air pollution on incident cardiovascular disease in Gothenburg, Sweden

Environmental Research ◽

10.1016/j.envres.2017.05.036 ◽

2017 ◽

Vol 158 ◽

pp. 61-71 ◽

Cited By ~ 54

Author(s):

Leo Stockfelt ◽

Eva M. Andersson ◽

Peter Molnár ◽

Lars Gidhagen ◽

David Segersson ◽

...

Keyword(s):

Cardiovascular Disease ◽

Air Pollution ◽

Long Term Effects ◽

Particulate Air Pollution ◽

Incident Cardiovascular Disease

Download Full-text

Ultrastructural investigations of MDL 19,660-induced effects on the canine platelet and megakaryocyte

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100159412 ◽

1990 ◽

Vol 48 (3) ◽

pp. 374-375

Author(s):

D.E. Loudy ◽

J. Sprinkle-Cavallo ◽

J.T. Yarrington ◽

F.Y. Thompson ◽

J.P. Gibson

Keyword(s):

Antidepressant Drug ◽

Beagle Dogs ◽

Long Term Effects ◽

Short Term ◽

Platelet Counts ◽

Toxicological Studies ◽

Induced Aggregation ◽

Internal Architecture

Previous short term toxicological studies of one to two weeks duration have demonstrated that MDL 19,660 (5-(4-chlorophenyl)-2,4-dihydro-2,4-dimethyl-3Hl, 2,4-triazole-3-thione), an antidepressant drug, causes a dose-related thrombocytopenia in dogs. Platelet counts started to decline after two days of dosing with 30 mg/kg/day and continued to decrease to their lowest levels by 5-7 days. The loss in platelets was primarily of the small discoid subpopulation. In vitro studies have also indicated that MDL 19,660: does not spontaneously aggregate canine platelets and has moderate antiaggregating properties by inhibiting ADP-induced aggregation. The objectives of the present investigation of MDL 19,660 were to evaluate ultrastructurally long term effects on platelet internal architecture and changes in subpopulations of platelets and megakaryocytes.Nine male and nine female beagle dogs were divided equally into three groups and were administered orally 0, 15, or 30 mg/kg/day of MDL 19,660 for three months. Compared to a control platelet range of 353,000- 452,000/μl, a doserelated thrombocytopenia reached a maximum severity of an average of 135,000/μl for the 15 mg/kg/day dogs after two weeks and 81,000/μl for the 30 mg/kg/day dogs after one week.

Download Full-text