An approach for water pollution abatement

Previously the effects of pollution abatement were measured in terms of the size of reductions achieved. This paper demonstrates a method that can be used to measure effects in relation to the practical significance of the reductions for the people living in the area concerned. The approach used in the project Locally Adapted Regulatory Impact Analysis (LARIA), aims to overcome the problem of finding a correct balance between the size and cost of the effort required in relation to the benefit to society for conservation projects. The proposed methodology consists of four parts. First, the user interests in the Lake Mjøsa basin are determined, and relative weights expressing the importance is given to the users. Then, a water quality effect model was developed. Focus is put on developing a phosphorus effect model taking into account the biological availability of phosphorus. The third step is a model to express the benefit to society from improvement in water quality. The fourth step is to identify and rank all available abatement measures using information from the effect model and the cost of implementation of each measure.     

Water pollution abatement through re-use of municipal wastewater in agricultural systems

Direct or indirect discharging of municipal sewage into water bodies commonly results in water pollution and prolific growth of aquatic vegetation. To avoid this problem, part of the secondary-treated municipal wastewater collected from the city of Isfahan is used for irrigating a 5-ha agricultural research plot where various kinds of crops and trees are grown under close observation. The scheme takes advantage of the ‘living filter’ concept, where the biosystem consisting of soil and plants acts as a filter for removal of the polluting load that otherwise would have disturbed the environment. Experimental results obtained show that a nearly complete renovation of wastewater has been effected without causing any permanent or long-term damage to the surrounding ecosystem. Furthermore, an increase in product yield is achieved without any detectable lack in quality. It is concluded that the scheme is a feasible and successful method for re-utilisation of wastewater, provided that correct land management is exercised during the operation.     

大气质量提高与农业中的硫肥需求

论述了植物对硫素的生理需求,大气中含硫化合物的来源、组成与含量以及对植物生态系统的硫素补充作用,植物对气态硫化物的吸收、同化能力及适宜浓度等．近年来由于人类健康与生态环境的需要,世界各国纷纷通过法律体制对工业含硫废气的排放标准进行了严格控制,却导致了作物缺硫现象的频繁发生,在某些地区硫已成为限制农业生产的最重要肥料限制因素．为此,全球农业中硫肥的需求量猛增且有效性范围不断扩大,进而对硫肥的研究与开发利用提出了新的要求     

Air movement preferences observed in office buildings

Office workers’ preferences for air movement have been extracted from a database of indoor environmental quality surveys performed in over 200 buildings. Dissatisfaction with the amount of air motion is very common, with too little air movement cited far more commonly than too much air movement. Workers were also surveyed in a detailed two-season study of a single naturally ventilated building. About one-half the building’s population wanted more air movement and only 4% wanted less. This same ratio applied when the air movement in workspaces was higher than 0.2 m/s, the de facto draft limit in the current ASHRAE and ISO thermal environment standards. Preference for “less air motion” exceeded that for “more” only at thermal sensations of −2 (cool) or colder. These results raise questions about the consequences of the ASHRAE and ISO standards’ restrictions on air movement, especially for neutral and warm conditions.     

空气污染与神经退行性疾病

随着现代社会工业的发展,空气污染日益严重,空气污染对人体的损害也越来越大。空气污染中的有害物质,能通过各种途径引起各系统的疾病,甚至会影响儿童的身体和智力发育。研究发现,长期暴露或急性暴露在某些空气污染物中可以直接损伤中枢神经系统,或污染物引起呼吸系统和免疫系统等产生有害因子,通过外周循环到达大脑,导致大脑的神经炎症、神经毒性、氧化应激等反应,最终产生神经退行性病变,如阿尔茨海默病（Alzheimer’s disease,AD）、帕金森病（Parkinson’s disease,PD）等。     

Air pollution and health.

The effects of air pollution on human health are reviewed. Data from toxicology, epidemiology, clinical and laboratory exposures are presented as a basis for an emerging etiology. Sulfur dioxide, suspended particulates, nitrogen dioxide, photochemical oxidants, and carbon monoxide are examined as stress agents to the cardio-pulmonary system.     

Air pollution and allergic airway diseases

In the last decades, many studies have shown an increase in the prevalence of allergic rhinitis and asthma mainly in urban communities, especially in industrialized countries. Airborne pollutants such as diesel exhaust particles, ozone, nitrogen dioxide and sulphur dioxide have been implicated in the initiation and exacerbation of allergic airway diseases. Epidemiologic studies have shown clear associations between air pollution and allergic diseases, in vivo and in vitro studies have provided biologic link and potential molecular mechanisms. Particulate and gaseous pollutants can act both on the upper and lower airways to initiate and exacerbate cellular inflammation through interaction with the innate immune system. As a consequence, increased non-specific airway hyper-responsiveness and airway resistance have been observed in man. Diesel exhaust particles can both induce and exacerbate in vivo allergic responses. They can also modify the immune system's handling of the allergen. The effects of gaseous pollutants on immune responses to allergens are not fully understood. We review the different mechanisms involved in the enhancement of allergic inflammation by urban air pollutants, including effects on cytokine and chemokine production, as well as activation of different immune cells. We discuss the hypothesis that pollutants' effects on the immune system involve hierarchical oxidative stress. Susceptibility genes to air pollution inducing allergic diseases are also discussed.     

Air pollution by carcinogenic PAHs and plasma levels of p53 and p21(WAF1) proteins

We analyzed the effect of exposure to carcinogenic polycyclic aromatic hydrocarbons (c-PAHs) in ambient air on the plasma levels of p53 and p21^WAF1 proteins among city policemen, bus drivers and controls in three European cities: Prague (Czech Republic), Kosice (Slovakia) and Sofia (Bulgaria). p53 and p21^WAF1 proteins are key regulators of the cell cycle and are accepted as universal markers of genotoxic stress and DNA damage. In total 204 exposed subjects (100 smokers, 104 nonsmokers) and 152 controls (54 smokers, 98 nonsmokers) were analyzed. Personal exposure to c-PAHs was evaluated using personal samplers during the working shift. The levels of p53 and p21^WAF1 proteins were assessed by ELISA assay. There were no differences between the levels of either protein between exposed and controls, or smokers and nonsmokers, in any city. However, we observed significant differences in p53 plasma levels in all subjects regardless of the exposure status between the individual cities (median values: 5, 31, 234 pg/ml, p < 0.001, for Prague, Kosice and Sofia, respectively). The levels correspond to the differences in exposure levels to c-PAHs and benzo[a]pyrene (B[a]P) in the individual cities. A multiple linear regression analysis confirmed that c-PAHs exposure is a variable significantly affecting levels of both proteins in all locations. When all subjects were divided into the group exposed to below-median levels of c-PAHs and the group exposed to above-median levels of c-PAHs we found significantly higher p53, as well as p21^WAF1 levels in the above-median exposure group (p53, 167 pg/ml versus 25 pg/ml, p < 0.001; p21^WAF1, 2690 pg/ml versus 2600 pg/ml, p < 0.05). Among all subjects p53 plasma levels were positively correlated with p21^WAF1 levels, exposure to B[a]P, c-PAHs and levels of total DNA adducts; for p21^WAF1 levels we observed the positive correlation with cotinine, c-PAHs exposure, total and B[a]P-like DNA adduct levels. In conclusion our results suggest that p53 and p21^WAF1 proteins plasma levels may be useful biomarkers of c-PAHs environmental exposure.     

Macrobenthic community structure before and after pollution abatement in the Neches River estuary (Texas)

Macrobenthos and physicochemical conditions in the lower 39 km of the Neches River estuary were studied from August, 1984 to May, 1985. The results were compared with data collected in 1971–1972. Between 1972 and 1984 the permitted BOD waste load in the tidal Neches River was reduced from 123 125 kg d to 8717 kg d. River discharge and dissolved oxygen concentrations were consistently higher and salinity was lower, during the same seasons, during the 1984–1985 study. A total of 50 taxa of macrobenthos were collected in 1971–1972 and 104 taxa were collected in 1984–1985. The numbers of taxa per collection at each station in 1984–1985 were at least twice those found in 1971–1972. Minimum densities in 1984–1985 were much higher than the maximum densities in 1971–1972 at all stations. Patterns of dominance, Sorenson's similarity index, and diversity ( ) values indicated improved water quality in 1984–1985. Statistical analysis of macrobenthic diversity indicated significant differences between upper estuary and lower estuary stations in 1971–1972. No significant differences were found in 1984–1985. Significant differences in numbers of taxa, macrobenthos densities, and values between the two studies were found. Reductions of waste loads, increased river discharge, and deepening of the navigation channel were among the factors that probably contributed most to the changes in community structure of the macrobenthos observed.     

Air pollution: forest health and passive sampling

32nd Annual Air Pollution Workshop
Auburn University in Auburn, AL, USA, April 2000
Air pollution has profound effects on agriculture, forests and natural ecosystems. The first Air Pollution Workshop was held over 30 years ago, and the most vital issues have always been highlighted within this forum. This year, forest health and passive sampling of air pollutants were two key areas of interest.     

Acute effects of air pollution changes in schoolchildren: the Gardanne coal basin study

In the literature, studies devoted to shortterm effects of air pollution episodes in children have provided controversial results. To evaluate if acute air pollution changes in the Gardanne coal basin (France) could have deleterious effects on children's pulmonary function, we studied 160 children on two different days. Each in-school examination consisted of a short questionnaire and a spirometric assessment. The area included districts of high and low pollution levels. In the former, the two examinations took place at different air pollution levels whereas, in the latter, the air pollution levels were comparable. We obtained higher spirometric values during the second examination, regardless of air pollution changes and suggesting a learning effect, which vanished when we used FEV₁/FVC ratio. The difference in FEV₁/FVC between days of low and high pollution was significant but merely equal to 2%. There was no change of clinical symptom score.     

Air pollution and the lung: epidemiological approach

Epidemiological evidence has concurred with clinical and experimental evidence to correlate current levels of ambient air pollution, both indoors and outdoors, with respiratory effects. In this respect, the use of specific epidemiological methods has been crucial. Common outdoor pollutants are particulate matter, nitrogen dioxide, carbon monoxide, volatile organic compounds and ozone. Short-term effects of outdoor air pollution include changes in lung function, respiratory symptoms and mortality due to respiratory causes. Increase in the use of health care resources has also been associated with short-term effects of air pollution. Long-term effects of cumulated exposure to urban air pollution include lung growth impairment, chronic obstructive pulmonary disease (COPD), lung cancer, and probably the development of asthma and allergies. Lung cancer and COPD have been related to a shorter life expectancy. Common indoor pollutants are environmental tobacco smoke, particulate matter, nitrogen dioxide, carbon monoxide, volatile organic compounds and biological allergens. Concentrations of these pollutants can be many times higher indoors than outdoors. Indoor air pollution may increase the risk of irritation phenomena, allergic sensitisation, acute and chronic respiratory disorders and lung function impairment. Recent conservative estimates have shown that 1.5-2 million deaths per year worldwide could be attributed to indoor air pollution. Further epidemiological research is necessary to better evaluate the respiratory health effects of air pollution and to implement protective programmes for public health.