Impact of urban expansion on the air pollution landscape: A case study of Hanoi, Vietnam.

The rapid urban expansion of Hanoi over the last few decades has transformed a lot of agricultural land into urban land uses accompanying pollution by traffic, industrial, and residential emission sources. In this work, the impact of urban expansion on the air pollution landscape has been assessed using the NO and SO ambient concentrations measured by passive diffusion samplers at 176 sites across the nine urban and the five peri-urban districts of Hanoi spanning an area of 921 km. The NO values ranged from 5.

The future European standard to determine odour in ambient air by using field inspection.

This paper presents the methodologies to determine odour in ambient air by field inspection that will be a new European standard. The objective is to characterise the odour in a defined area. Without making a link with potential annoyance due to the presence of odours, the described methods propose the way to characterise an exposed environment.

Ozone measurements along vertical transects in the Alps.

To investigate the vertical profiles of air pollutants in the boundary layer, aircraft and balloon-born measurements and measurements using a cable car as an instrument platform have been performed in different parts of the Alps. This on-line monitoring of atmospheric pollutants requires expensive and sophisticated techniques. In order to control ambient air quality in remote regions, where no infrastructure like power supply is available, simple instruments are required.

Field intercomparison of diffusive samplers for measuring ammonia.

Agricultural production systems are recognised as a major source of atmospheric ammonia. Deposition of ammonia and ammonium may contribute to undesired changes in oligotrophic ecosystems. The continuous measurement of atmospheric ammonia requires expensive and sophisticated techniques and is performed only in a very restrict number of ambient air stations in Europe.

Isopropanol and methylformate exposure in a foundry: exposure data and neurobehavioural measurements.

Objectives: The aim of this study was to determine the dose-effect relationship between solvent exposure and acute neurobehavioural effects at the worksite.

Methods: In a balanced design, ten workers in a Swiss foundry were monitored for 15 days at ten different times during work. Urine samples were taken in the morning and at the time of examination, and personal exposure to isopropanol and methylformate was measured with active samplers.

Experimental exposure to methylformate and its neurobehavioral effects.

Objectives: The aim of the study was to investigate the acute effects of experimental methylformate exposure on the nervous system.

Methods: In an exposure chamber, 20 subjects were exposed to methylformate at 100 ppm [Swiss maximum allowable concentration (MAC)] for 8 h. The same number of subjects with the same ages (between 20 and 30 years), gender and education level (university) were examined by the same procedure as a control group.

[Measurement and evaluation of environmental odors].

The odor problem in the vicinity of a sludge drying plant was solved by installation of a biofilter. The success of this measure was examined by olfactometric measurements such as dilution to threshold determination and scaling of hedonic tone. The odor emissions were evaluated by questioning of the population in the neighbourhood of the plant.

[A passive sampler for nitrogen dioxide].

Passive samplers run without electric power supply, are easy to handle and thus are suitable for exposure measurements in epidemiological studies, to evaluate indoor air quality, to control ambient concentrations etc. Passive sampler values agree with continuous measuring apparatus within 85 to 105% and the lower detection limit is 4 micrograms/m3 for a one week exposure or longer.

[Air and noise pollution caused by traffic in a small Swiss town].

In order to evaluate the extent of annoyance caused by air pollution and noise immissions, we measured the values in the small town of Uznach, which is crossed by a narrow and sloped street with a heavy traffic. The results revealed that noise immissions exceed the "alarm-value" of 70 dB(A) and that pollution of the air is situated in the range of limit values.

[Annoyance by odors].

In this study we attempted to measure the odour immissions objectively and to bring them in relation with the subjective statements of the population. As measure of odour intensity, merely the distance from the source of emission could be considered. A self-rating thermometer as well as subjective complaints, such as sleeplessness, nausea and the intention to move, permitted us to derive distinct annoyance levels at various distances from the source.

[Irtitation by smell in the neighborhood of a garbage burning plant].

Dilution threshold values were measured using sensory methods for an evaluation of odorous emissions of an incineration plant. The dispersion of odours was estimated based on recording of the local wind. The level of public annoyance in the neighbouring residential areas will be assessed by special questionnaires.