BACKGROUND Second-hand smoke is associated with adverse health effects. Many countries have extended smoke-free policies to public buildings and workplaces such as hospitals, but mental health units have usually been exempted from complete smoke-free bans. The objective of this study was to evaluate second-hand smoke levels in mental health units with different types of smoking bans. Method We ...

Forest soils play a critical role in the sequestration of atmospheric CO2 and subsequent attenuation of global warming. The nature and properties of organic matter in soils have an influence on the sequestration of carbon. In this study, soils were collected from representative forestlands, including a subtropical evergreen broad-leaved forest (EBF), a coniferous forest (CF), a subalpine dwarf ...

Contaminant carbon (blank carbon) was studied for its impact on the carbon isotope measurements (∆14C and δ13C) of 3 organic compound classes of oceanic particulate organic matter. Two methods of blank correction and associated uncertainties were studied. First, the carbon blanks were quantified manometrically and the isotope ratios of the blank carbon were measured directly. Second, the isotop...

Accurate determinations of total (TOC), dissolved (DOC) and particulate (POC) organic carbon concentrations are critical for understanding the geochemical, environmental, and ecological roles of aquatic organic matter. Of particular significance for the drinking water industry, TOC measurements are the basis for compliance with US EPA regulations. The results of an interlaboratory comparison de...

Aerosols are of central importance for atmospheric chemistry and physics, the biosphere, climate, and public health. The airborne solid and liquid particles in the nanometer to micrometer size range influence the energy balance of the Earth, the hydrological cycle, atmospheric circulation, and the abundance of greenhouse and reactive trace gases. Moreover, they play important roles in the repro...

Fouling of membrane surfaces by particulate matter and large organic molecules is relatively common for pressure-driven membrane processes, namely, reverse osmosis (RO), nanofiltration (NF), and ultrafiltration (UF). Donnan membrane process (DMP) or Donnan Dialysis is driven by electrochemical potential gradient across a semipermeable ion exchange membrane. Theoretically, DMP is not susceptible...

Water, suspended particulate matter (SPM), and sediment samples were collected from ten rivers in Tianjin and analyzed for 16 polycyclic aromatic hydrocarbons (PAHs), dissolved organic carbon (DOC), particulate organic carbon (POC) in SPM and total organic carbon (TOC) in sediment. The behavior and fate of PAHs influenced by these parameters were examined. Generally, organic carbon was the prim...

The global atmospheric distribution and long-range transport (LRT) potential of three polycyclic aromatic hydrocarbons (PAH) - anthracene, fluoranthene and benzo[a]pyrene - are studied. The model used is a global aerosol-chemistry-transport-model, which is based on an atmospheric general circulation model. The model includes an in-built dynamic aerosol model coupled to two-dimensional surface c...