An attempt to prop up an EPA obsession. Does fine dust kill you?

Because motor vehicles put out a lot of fine particles from their exhausts, the EPA has long tried to show that such pollution kills you.  But the EPA are not alone in that.  With great regularity studies from all sources emerge which show that living near a major road has adverse health consequences.  I have critiqued many of those studies over the years and ALL of them fail to allow for confounding.  For instance, it is mainly the poor who live beside major roads and the poor are unhealthier anyway. So the association between roads and health is actually  an association between poverty and health -- an association we knew all along.

The study below seems to be similarly inconclusive. The poor probably live in more polluted areas. As far as I can tell they failed to account for poverty and other social class variables that could have mediated the findings.  And they have no actual data on anyone's cause of death.  Because a person who died lived near a polluted area they simply assume that pollution was the cause of his death.  That seems to me to be assuming what you have to prove.

Futhermore all the associations reported were in the form of  very low relative risks clustered around 1.0, which is most parsimoniously interpreted as "no association".  There is much more that could be said about this study and Steve Milloy has said it.  Like many studies before it, this study too is junk


Long-Term PM 2.5 Exposure and Respiratory, Cancer, and Cardiovascular Mortality in Older US Adults

Vivian C Pun, Fatemeh Kazemiparkouhi, Justin Manjourides, Helen H Suh

Abstract

The impact of chronic exposure to fine particulate matter (particulate matter with an aerodynamic diameter less than or equal to 2.5 μm (PM2.5)) on respiratory disease and lung cancer mortality is poorly understood. In a cohort of 18.9 million Medicare beneficiaries (4.2 million deaths) living across the conterminous United States between 2000 and 2008, we examined the association between chronic PM2.5 exposure and cause-specific mortality. We evaluated confounding through adjustment for neighborhood behavioral covariates and decomposition of PM2.5 into 2 spatiotemporal scales. We found significantly positive associations of 12-month moving average PM2.5 exposures (per 10-μg/m3 increase) with respiratory, chronic obstructive pulmonary disease, and pneumonia mortality, with risk ratios ranging from 1.10 to 1.24. We also found significant PM2.5-associated elevated risks for cardiovascular and lung cancer mortality. Risk ratios generally increased with longer moving averages; for example, an elevation in 60-month moving average PM2.5 exposures was linked to 1.33 times the lung cancer mortality risk (95% confidence interval: 1.24, 1.40), as compared with 1.13 (95% confidence interval: 1.11, 1.15) for 12-month moving average exposures. Observed associations were robust in multivariable models, although evidence of unmeasured confounding remained. In this large cohort of US elderly, we provide important new evidence that long-term PM2.5 exposure is significantly related to increased mortality from respiratory disease, lung cancer, and cardiovascular disease.

American Journal of Epidemiology, Volume 180, Issue 12, 15 December 2014, Pages 1159–1167


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