Secondary Organic Aerosol Generated from Biomass Burning Emitted Phenolic Compounds: Oxidative Potential, Reactive Oxygen Species, and Cytotoxicity.

Phenolic compounds are largely emitted from biomass burning (BB) and have a significant potential to form SOA (Phc-SOA). However, the toxicological properties of Phc-SOA remain unclear. In this study, phenol and guaiacol were chosen as two representative phenolic gases in BB plumes, and the toxicological properties of water-soluble components of their SOA generated under different photochemical ages and NO levels were investigated.

Chemical Investigation of Household Solid Fuel Use and Outdoor Air Pollution Contributions to Personal PM Exposures.

In communities with household solid fuel use, transitioning to clean stoves/fuels often results in only moderate reductions in fine particulate matter (PM) exposures; the chemical composition of those exposures may help explain why. We collected personal exposure (men and women) and outdoor PM samples in villages in three Chinese provinces (Shanxi, Beijing, and Guangxi) and measured chemical components, including water-soluble organic carbon (WSOC), ions, elements, and organic tracers. Source contributions from chemical mass balance modeling (biomass burning, coal combustion, vehicles, dust, and secondary inorganic aerosol) were similar between outdoor and personal PM samples.

Source Apportionment of Fine Organic Particulate Matter (PM) in Central Addis Ababa, Ethiopia.

The development of infrastructure, a rapidly increasing population, and urbanization has resulted in increasing air pollution levels in the African city of Addis Ababa. Prior investigations into air pollution have not yet sufficiently addressed the sources of atmospheric particulate matter. This study aims to identify the major sources of fine particulate matter (PM) and its seasonal contribution in Addis Ababa, Ethiopia.

Cytotoxicity and chemical composition of women's personal PM exposures from rural China.

Personal exposure PM samples aid in determining the sources and chemical composition of real-world exposures, particularly in settings with household air pollution. However, their use in toxicological research is limited, despite uncertainty regarding health effects in these settings and evidence of differential toxicity among PM sources and components. This study used women's PM exposure samples collected using personal exposure monitoring in rural villages in three Chinese provinces (Beijing, Shanxi, and Sichuan) during summer and winter.

Chemical Characterization and Seasonality of Ambient Particles (PM) in the City Centre of Addis Ababa.

Ambient air pollution is a growing public health concern in major African cities, including Addis Ababa (Ethiopia), where little information is available on fine particulate matter (PM, with aerodynamic diameter <2.5 µm) pollution. This paper aims to characterize annual PM, including bulk composition and seasonal patterns, in Addis Ababa.

Source Apportionment of Coarse Particulate Matter (PM) in Yangon, Myanmar.

The Republic of the Union of Myanmar is one of many developing countries facing concerns about particulate matter (PM). Previously, a preliminary study of PM in 2018 suggested that the main source of PM in Yangon, the former capital, was vehicle emissions. However, this suggestion was not supported by any chemical composition data.

Impacts of stove/fuel use and outdoor air pollution on chemical composition of household particulate matter.

Biomass combustion for cooking and heating releases particulate matter (PM ) that contributes to household air pollution. Fuel and stove types affect the chemical composition of household PM, as does infiltration of outdoor PM. Characterization of these impacts can inform future exposure assessments and epidemiologic studies, but is currently limited.

Source apportionment of fine particulate matter in a Middle Eastern Metropolis, Tehran-Iran, using PMF with organic and inorganic markers.

With over 8 million inhabitants and 4 million motor vehicles on the streets, Tehran is one of the most crowded and polluted cities in the Middle East. Frequent exceedances of national daily PM limit have been reported in this city during the last decade, yet, the chemical composition and sources of fine particles are poorly determined. In the present study, 24-hour PM samples were collected at two urban sites during two separate campaigns, a one-year period from 2014 to 2015 and another three-month period at the beginning of 2017.

Differences in chemical composition of PM emissions from traditional versus advanced combustion (semi-gasifier) solid fuel stoves.

A common strategy to improve indoor air quality in households burning coal and biomass is the introduction of advanced combustion solid fuel stoves, which can use existing fuels yet emit fewer pollutants. Chemical composition of PM is affected by numerous combustion parameters, but is often not considered in energy transitions, despite varying toxicity among chemical components. We analyzed PM emissions from combustion of solid fuels (coal, wood, and straw; whole and pelletized) in a variety of stoves (cookstoves and heating stoves; traditional and semi-gasifier, including forced versus natural draft and fixed versus reciprocating grate).

Effectiveness of a Household Energy Package in Improving Indoor Air Quality and Reducing Personal Exposures in Rural China.

We evaluated whether an energy package comprising a low-polluting semigasifier cookstove with chimney, water heater, and pelletized biomass fuel would improve air pollution in China. We measured the stove use, 48-h air pollution exposures (PM, black carbon), and kitchen concentrations (PM, black carbon, carbon monoxide, nitrogen oxides) for 205 women, along with ambient PM. Over half ( = 125) were offered the energy package after baseline assessment, forming "treated" and "untreated" groups, and we repeated the measurements up to 3 occasions over 18-months.

Undisclosed financial ties between guideline writers and pharmaceutical companies: a cross-sectional study across 10 disease categories.

Objectives: To investigate the proportion of potentially relevant undisclosed financial ties between clinical practice guideline writers and pharmaceutical companies.

Design: Cross-sectional study of a stratified random sample of Australian guidelines and writers.

Setting: Guidelines available from Australia's National Health and Medical Research Council guideline database, 2012-2014, stratified across 10 health priority areas.

The Oxidative Potential of Personal and Household PM in a Rural Setting in Southwestern China.

The chemical constituents of fine particulate matter (PM) vary by source and capacity to participate in redox reactions in the body, which produce cytotoxic reactive oxygen species (ROS). Knowledge of the sources and components of PM may provide insight into the adverse health effects associated with the inhalation of PM mass. We collected 48 h household and personal PM exposure measurements in the summer months among 50 women/household pairs in a rural area of southwestern China where daily household biomass burning is common.

Seasonal variations in the oxidative stress and inflammatory potential of PM in Tehran using an alveolar macrophage model; The role of chemical composition and sources.

The current study was designed to assess the association between temporal variations in urban PM chemical composition, sources, and the oxidative stress and inflammatory response in an alveolar macrophage (AM) model. A year-long sampling campaign collected PM samples at the Sharif University in Tehran, Iran. PM-induced reactive oxygen species (ROS) production was measured both with an acellular dithiothreitol consumption assay (DTT-ROS; ranged from 2.

The Influence of Industry Sponsorship on the Research Agenda: A Scoping Review.

Background: Corporate interests have the potential to influence public debate and policymaking by influencing the research agenda, namely the initial step in conducting research, in which the purpose of the study is defined and the questions are framed.

Objectives: We conducted a scoping review to identify and synthesize studies that explored the influence of industry sponsorship on research agendas across different fields.

Search Methods: We searched MEDLINE, Scopus, and Embase (from inception to September 2017) for all original research and systematic reviews addressing corporate influence on the research agenda.

Chemical composition and source apportionment of ambient, household, and personal exposures to PM in communities using biomass stoves in rural China.

Fine particulate matter (PM) has health effects that may depend on its sources and chemical composition. Few studies have quantified the composition of personal and area PM in rural settings over the same time period. Yet, this information would shed important light on the sources influencing personal PM exposures.

Seasonal trends in the composition and sources of PM and carbonaceous aerosol in Tehran, Iran.

Currently PM is a major air pollution concern in Tehran, Iran due to frequent high levels and possible adverse impacts. In this study, which is the first of its kind to take place in Tehran, composition and sources of PM and carbonaceous aerosol were determined, and their seasonal trends were studied. In this regard, fine PM samples were collected every six days at a residential station for one year and the chemical constituents including organic marker species, metals, and ions were analyzed by chemical analysis.

Source apportionment of PM organic carbon in the San Joaquin Valley using monthly and daily observations and meteorological clustering.

Two hundred sixty-three fine particulate matter (PM) samples collected on 3-day intervals over a 14-month period at two sites in the San Joaquin Valley (SJV) were analyzed for organic carbon (OC), elemental carbon (EC), water soluble organic carbon (WSOC), and organic molecular markers. A unique source profile library was applied to a chemical mass balance (CMB) source apportionment model to develop monthly and seasonally averaged source apportionment results. Five major OC sources were identified: mobile sources, biomass burning, meat smoke, vegetative detritus, and secondary organic carbon (SOC), as inferred from OC not apportioned by CMB.

The oxidative potential of PM2.5 exposures from indoor and outdoor sources in rural China.

Background: Airborne particulate matter (PM) is a widespread environmental exposure and leading health risk factor. The health effects of PM may be mediated by its oxidative potential; however, the combustion and non-combustion sources and components of PM responsible for its oxidative potential are poorly understood, particularly in low- and middle-income rural settings where coal and biomass burning for cooking and heating contribute to PM exposure.

Methods: We measured 24-h personal exposures to fine particulate matter (PM2.

Seasonal and Diurnal Air Pollution from Residential Cooking and Space Heating in the Eastern Tibetan Plateau.

Residential combustion of solid fuel is a major source of air pollution. In regions where space heating and cooking occur at the same time and using the same stoves and fuels, evaluating air-pollution patterns for household-energy-use scenarios with and without heating is essential to energy intervention design and estimation of its population health impacts as well as the development of residential emission inventories and air-quality models. We measured continuous and 48 h integrated indoor PM2.

Seasonal variation in outdoor, indoor, and personal air pollution exposures of women using wood stoves in the Tibetan Plateau: Baseline assessment for an energy intervention study.

Cooking and heating with coal and biomass is the main source of household air pollution in China and a leading contributor to disease burden. As part of a baseline assessment for a household energy intervention program, we enrolled 205 adult women cooking with biomass fuels in Sichuan, China and measured their 48-h personal exposure to fine particulate matter (PM2.5) and carbon monoxide (CO) in winter and summer.