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Reactive Oxygen Species Generation Linked to Sources of Atmospheric Particulate Matter and Cardiorespiratory Effects.

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Reactive Oxygen Species Generation Linked to Sources of Atmospheric Particulate Matter and Cardiorespiratory Effects.

Environ Sci Technol. 2015 Oct 12;

Authors: Bates JT, Weber RJ, Abrams J, Verma V, Fang T, Klein M, Strickland M, Sarnat SE, Chang HH, Mulholland JA, Tolbert PE, Russell AG

Abstract
Exposure to atmospheric fine particulate matter (PM2.5) is associated with cardiorespiratory morbidity and mortality, but the mechanisms are not well understood. We assess the hypothesis that PM2.5 induces oxidative stress in the body via catalytic generation of reactive oxygen species (ROS). A dithiothreitol (DTT) assay was used to measure the ROS-generation potential of water-soluble PM2.5. Source apportionment on ambient (Atlanta, GA) PM2.5 was performed using the Chemical Mass Balance Method with ensemble-averaged source impact profiles. Linear regression modeling was used to relate PM2.5 emissions sources to ROS-generation potential and to estimate historical levels of DTT activity for use in an epidemiologic analysis for the period 1998-2009. Light-duty gasoline vehicles (LDGV) exhibited the highest intrinsic DTT activity, followed by biomass burning (BURN) and heavy-duty diesel vehicles (HDDV) (0.11 ± 0.02, 0.069 ± 0.02, and 0.052 ± 0.01 nmol min-1 ?g-1source, respectively). BURN contributed the largest fraction to total DTT activity over the study period, followed by LDGV and HDDV (45%, 20% and 14%, respectively). DTT activity was more strongly associated with emergency department visits for asthma/wheezing and congestive heart failure than PM2.5. This work provides further epidemiologic evidence of a biologically plausible mechanism, that of oxidative stress, for associations of adverse health outcomes with PM2.5 mass, and supports continued assessment of the utility of the DTT activity assay.biological plausibility to associations of adverse health outcomes with PM2.5 mass, supporting oxidative stress as a mechanism.

PMID: 26457347 [PubMed – as supplied by publisher]

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Two Johnsonite® Vinyl Flooring Collections Earn asthma & allergy friendly … – Interiors & Sources

Two Johnsonite® Vinyl Flooring Collections Earn asthma & allergy friendly …
Interiors & Sources
Allergy Standards Limited (ASL), in partnership with top medical experts and the Asthma and Allergy Foundation of America (AAFA), created the asthma & allergy friendly Certification Program in 2006 in the United States. The certification program …

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Fifty years of pediatric asthma in developed countries: How reliable are the basic data sources?

Fifty years of pediatric asthma in developed countries: How reliable are the basic data sources?

Pediatr Pulmonol. 2011 Sep 8;

Authors: Chawla J, Seear M, Zhang T, Smith A, Carleton B

Abstract
Given the difficulties in diagnosing, or even defining, asthma in children, claims of a pediatric asthma epidemic in Canada and other developed countries are accepted with surprisingly little critical examination. We reviewed a broad range of data sources to understand how the epidemic evolved during the last 50 years and also to assess the reliability of the conclusions drawn from that data. We obtained Canadian National and Provincial data from Statistics Canada National Population Health Survey, and the British Columbia Ministry of Health respiratory database. International data were obtained by extensive review of pediatric asthma epidemiological surveys published during the last 50 years. In many developed countries, there have been three separate epidemics involving different aspects of pediatric asthma during the last 50 years: a double peaked mortality epidemic (1960s and 1980s), a hospital admission epidemic (peaked around 1990) and a steadily growing epidemic of children who report asthmatic symptoms on questionnaires. Canadian pediatric rates for asthma mortality (1-2/million/year) and hospital admission (1-2/thousand/year) are low and have fallen for the last 20 years. Rates based on questionnaire studies are high (10-15/hundred) and rose steadily over the same period. Objective reductions in asthma deaths and hospital admission likely reflect improved education and treatment programmes. Current claims of an epidemic based largely on subjective self-reported symptoms require more careful analysis. The possibility that symptom misperception, disease fashions, and poor recall, may be part of the explanation for the current high levels of self-reported symptoms deserves more attention. Pediatr Pulmonol. © 2011 Wiley-Liss, Inc.

PMID: 21905263 [PubMed – as supplied by publisher]

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