Time budget study and total exposure assessment to air pollutants of Hong Kong population

Abstract

During the last twenty years, Hong Kong continuously upgraded herself to become a leading world commercial and financial centre. Increasing affluence of the society at large always led to a raise in the expectations about the quality of the life as well as the environment. The high population density, the scarcity of land sources, the crowded city traffic, and etc, made the population more and more proximate to the high levels of air pollution. The deterioration of the environment had the potential to endanger the health of the Hong Kong population. Of paramount importance is the total amount of pollutants an individual would expose. Accordingly, this study intended to evaluate the time budget and total exposure of the Hong Kong population to air pollutants. The study composes of two major parts. The first part was to determine the daily activity pattern of Hong Kong population. The second part was to determine the air pollutant concentrations in different individual microenvironments. In order to reveal the time activity pattern of Hong Kong population, a customarily made survey protocol was developed and was found to be quite successful. The survey was conducted continuously for about 6 months, with 400 questionnaires successfully collected through telephone interviews. The information collected from the questionnaires was analyzed and the time budget of Hong Kong people was obtained. Meanwhile, the major pollutant concentrations, like carbon monoxide, nitrogen oxides and respirable suspended particulate, were measured in a number of selected microenvironments. Even though carbon dioxide is not considered as air pollutant, it was also used as an indicator for ventilation effectiveness. The results of this study revealed that Hong Kong people spent over 89% of their daily time indoors. The pollutant concentrations were found to be extremely high in pubs, restaurants and enclosed transits. Although the pollutant levels were not particularly high at home of most Hong Kong people, the long time span at home might also cause adverse health effect to human being. The significance of this study is that the results could help inform the policy makers of necessary actions that needed to be taken in order to reduce the health risk of the total population.