Monitoring the levels of brominated and organophosphate flame retardants in passenger cars: Utilisation of car air filters as active samplers

Filters in residential and office air conditioning(A/C) systems have been used as sampling devices for monitoring different pollutants.However,cabin air filters(CAFs) in the A/C system of passenger cars have not been utilised for this purpose.In this study,we collected22 used CAFs from passenger cars in Hanoi,Vietnam to analyse for 8 polybrominated diphenyl ethers(PBDEs) and 10 organophosphate esters(OPEs).All the analytes were detected in more than 50% of samples with the exception of BDE153 an...     

Characterization of particle number concentrations and PM<Subscript>2.5</Subscript> in a school: influence of outdoor air pollution on indoor air

Background, Aim and Scope  

The impact of air pollution on school children’s health is currently one of the key foci of international and national agencies. Of particular concern are ultrafine particles which are emitted in large quantities, contain large concentrations of toxins and are deposited deeply in the respiratory tract.     

Combustion sources of particles: 2. Emission factors and measurement methods

Emissions from the combustion of biomass and fossil fuels are a significant source of particulate matter (PM) in ambient outdoor and/or indoor air. It is important to quantify PM emissions from combustion sources for regulatory and control purposes in relation to air quality. In this paper, we review emission factors for several types of important combustion sources: road transport, industrial facilities, small household combustion devices, environmental tobacco smoke, and vegetation burning. We also review current methods for measuring particle physical characteristics (mass and number concentrations) and principles of methodologies for measuring emission factors. The emission factors can be measured on a fuel-mass basis and/or a task basis. Fuel-mass based emission factors (e.g., g/kg of fuel) can be readily used for the development of emission inventories when the amount of fuels consumed are known. Task-based emission factors (g/mile driven, g/MJ generated) are more appropriate when used to conduct comparisons of air pollution potentials of different combustion devices. Finally, we discuss major shortcomings and limitations of current methods for measuring particle emissions and present recommendations for development of future measurement techniques.     

Copper, Copper Mining Effluents and Grazing as Potential Determinants of Algal Abundance and Diversity in Northern Chile

We experimentally tested threealternative hypotheses to explain the low algaldiversity and abundance in an intertidal zonereceiving the effluents of the copper mine El Salvadorin northern Chile. Our results demonstrated thatalgae were able to grow at the levels of dissolvedcopper detected in coastal waters of the area. Duringthe assays, growth and regeneration in several red,green and brown adult algae and juvenile Lessonia nigrescens were normal at copper levels of150 g L^-1 or, in some cases, higher. Wealso found that the coastal sea water mixed with theeffluent was not lethal to algae, although in somecases minor effects on growth were detected. Theseresults indicate that today's low algal diversity andabundance can not be explained by the current copperlevels in the area nor by the effect of the effluent.Exclusion of grazers, however, resulted in a fastcolonization by various algal species. This, togetherwith atypically high grazer density at the areas underthe influence of the effluent, strongly suggests thatherbivory, a factor not directly related to the miningoperation, is likely to be responsible for the lowalgal diversity and abundance in the studied locality.     

Landscape-Based Assessment of Human Disturbance for Michigan Lakes

Assessment of lake impairment status and identification of threats’ type and source is essential for protection of intact, enhancement of modified, and restoration of impaired lakes. For regions in which large numbers of lakes occur, such assessment has usually been done for only small fractions of lakes due to resource and time limitation. This study describes a process for assessing lake impairment status and identifying which human disturbances have the greatest impact on each lake for all lakes that are 2 ha or larger in the state of Michigan using readily available, georeferenced natural and human disturbance databases. In-lake indicators of impairment are available for only a small subset of lakes in Michigan. Using statistical relationships between the in-lake indicators and landscape natural and human-induced measures from the subset lakes, we assessed the likely human impairment condition of lakes for which in-lake indicator data were unavailable using landscape natural and human disturbance measures. Approximately 92% of lakes in Michigan were identified as being least to marginally impacted and about 8% were moderately to heavily impacted by landscape human disturbances. Among lakes that were heavily impacted, more inline lakes (92%) were impacted by human disturbances than disconnected (6%) or headwater lakes (2%). More small lakes were impacted than medium to large lakes. For inline lakes, 90% of the heavily impacted lakes were less than 40 ha, 10% were between 40 and 405 ha, and 1% was greater than 405 ha. For disconnected and headwater lakes, all of the heavily impacted lakes were less than 40 ha. Among the anthropogenic disturbances that contributed the most to lake disturbance index scores, nutrient yields and farm animal density affected the highest number of lakes, agricultural land use affected a moderate number of lakes, and point-source pollution and road measures affected least number of lakes. Our process for assessing lake condition represents a significant advantage over other routinely used methods. It permits the evaluation of lake condition across large regions and yields an overall disturbance index that is a physicochemical and biological indicator weighted sum of multiple disturbance factors. The robustness of our approach can be improved with increased availability of high-resolution disturbance datasets.     

Determination of EC 50 toxicity data of selected heavy metals toward Heterocypris incongruens and their comparison to ��direct-contact�� and microbiotests

The sensitivity of Heterocypris incongruens to selected heavy metal ions is discussed. Although the Ostracodtoxkit ${\textregistered}$ has been present on the market for a few years, data on its selectivity and sensitivity to toxicants is scarce; such data is indispensable when interpreting the results of sediment toxicity. The LC₅₀ and EC₅₀ results with the Ostracodtoxkit ${\textregistered}$ are compared with those obtained with other commercially available ??direct-contact?? tests (utilizing Hyalella azteca and Chironomus riparius) and microbiotests for assessing the toxicity of aqueous samples (Vibrio fischeri, Daphnia magna, and Selenastrum capricornatum). The sensitivity of H. incongruens to metal ions (Cd^2?+?>?>Hg^2?+?> Cu^2?+?>Cr^6?+?>Ni^2?+???Mn^7?+?>Zn^2?+?>Pb^2?+?>Li^1?+?> Fe^3?+?) was found to be similar to that of H. azteca and of C. riparius. The Ostracodtoxkit ${\textregistered}$ has shown itself to be an efficient and reliable element of test batteries for toxicity determination.     

Classification of the Substances on the Basis of the Acute-Toxic-Class Method (ATC)

The acute-toxic-class method (ATC) is an alternative to the classical LD₅₀ test. Four substances were tested with an ATC testing procedure. The results were compared with LD₅₀ data obtained from the literature. Great importance was attached to the observations of toxic signs following administration. The results of this study have shown that the ATC method allows allocation to toxicity classes in the same manner as on the basis of the classical LD₅₀ tests. The ATC method uses fewer animals and yields the same information on toxic signs. Introducing the ATC method into the quality system allows estimating the acute oral toxicity of chemicals according to the Organisation for Economic Cooperation and Development (OECD; OECD, 1992, 1996).