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PubMed2006

Estimation of land use specific runoff and pollutant concentration for Tapi River basin in India.

Non-point source (NPS) pollution is the result of various land use practices such as agriculture, sites of construction and waste disposal, urban development and so on. The control of NPS pollution is possible by regular monitoring and assessment on watershed basis to educate people for implementing well-known structural and non-structural measures. Recent trend is to use GIS based modelling tool for assessment of rainfall-runoff and non-point loading. The approach requires generation and analysis of basin wide data on various features of land and estimates of Event Mean Concentrations (EMCs) of pollutants in the runoff. In the present paper, basin wide data in different districts of Tapi basin has been analysed for land use distribution; fertilizer application; low, medium and high-density habitation; and annual rainfall. Coefficients of runoff have been estimated considering pervious and impervious area for different land use types, and compared with the reported values for Indian conditions. The estimated mean annual runoff flow indicated that two districts Jalgaon and Dhule contribute maximum runoff to the Tapi River. Estimates of EMCs for BOD and nutrients (N and P) in the runoff from various districts are useful in GIS-based modelling study for NPS pollution assessment.

Agriculture↗
PubMed2006

Risk assessment of organic pesticides pollution in surface water of Hangzhou.

Advances in research on pollution of organic pesticides (OPs) in surface water, pollution survey and risk assessments of organochlorine pesticides (OCPs) and organophosphorus pesticides (OPPs) of surface water in Hangzhou are conducted. Total concentrations of dichloro-diphenyl-trichloroethane (DDT) and hexachloride-benzene (HCH) in surface water were observed to be 0-0.270 microg/L and 0-0.00625 microg/L respectively. DDE, as a metabolite of DDT and many species of OPP(S) were determined in some samples of surface water. Parathion, the main pollutant among OPPs in surface water of Hangzhou, was observed to be 0-0.445 microg/L. Based on these experimental results, health risk assessments on the organic pollution are developed. It is observed that the total risk "R (T)" at present time of surface water in Hangzhou is mainly contributed by organophosphorus pesticides, especially Parathion; HCH and DDT are not the main contaminants; on the contrary, organophosphorous pesticides, especially Parathion, must be of concern at the present time.

China↗
PubMed2006

Effects of polluting soil with cassava mill effluent on the bacteria and fungi populations of a soil cultivated with maize.

The study was carried out to investigate the effects of application of cassava mill effluent on bacteria and fungi types and population in a soil grown to maize (Zea Mays L.) Microbial populations were determined before pollution of soil with cassava mill effluent, six weeks after pollution with effluent and at the end of the experiment. Results obtained showed that bacteria and fungi populations increased with time as rates of pollution increased. It was also observed that some bacteria present in the soil at the beginning of the experiment and up to the sixth week after pollution with effluent became extinct at the end of the experiment.

Agriculture↗
PubMed2006

Inorganic constituents of urban air pollution in the Lazio region (Central Italy).

A field study was carried out at six locations in the Lazio region (Central Italy) aimed at characterising atmospheric particulate matter (PM10 and PM2.5) from the point of view of the chemical composition and grain size distribution of the particles, the mixing properties of the atmosphere, the frequency and relevance of natural events. The combination of four different analytical techniques (ion chromatography, X-ray fluorescence and ICP for inorganic components, thermo-optical analysis for carbon compounds) yielded sound results in terms of characterisation of the air masses. During the first three months of the study (October-December 2004), many pollution events of natural (sea-salt or desert dust episodes) or anthropogenic nature were identified and characterised. More than 90% of the collected mass was identified by chemical analysis. The central role played by the mixing properties of the lower atmosphere when pollution events occurred was highlighted. The results show a major impact of primary anthropogenic pollutants on traffic stations and a homogeneous distribution of secondary pollutants over the regional area. An evaluation of the sources of PM and an identification of possible reliable tracers were obtained using a chemical fractionation procedure.

Air Pollutants↗
PubMed2006

Inventory of emissions of primary air pollutants in the city of Kocaeli, Turkey.

This study aims to obtain a reliable inventory of the emission rates of the principal air pollutants including PM, SO2, NOx) and CO in Kocaeli, Turkey. In the first stage, the pollutant sources classified as point, area and line sources are determined in the area. Then the annual emission rates of the pollutants released from these sources are estimated by the emission factors given by USEPA and CORINAIR. Results show that the annual emission rates for PM, SO2, NOx) and CO are 2195 tons, 5342 tons, 14632 tons and 23095 tons, respectively. On the other hand, the pollutant group with the highest contribution to total emission rate is determined as the point sources for NOx, which is responsible for 73% of total NOx emission, while it is the area sources for PM, SO2 and CO with the contribution percentages of 75, 76 and 69, respectively.

Air Pollutants↗
PubMed2006

A numerical and experimental study of pollutant dispersion in a traffic tunnel.

Three-dimensional turbulent flow and dispersion of gaseous pollutants carbon monoxide (CO) and nitrogen oxides (NOx) in a road tunnel was modeled using the standard k-epsilon turbulence model and solved numerically using the finite volume method. Vehicle emissions were estimated from the measured traffic flow rates and modeled as banded line sources along the tunnel floor. The effects of fan ventilation and piston effect of moving vehicles on the airflow and pollutant dilution were examined. The numerical results reveal that a peak velocity exists near the tunnel floor due to the piston effect of vehicles. The cross-sectional concentrations of air pollutants are non-uniformly distributed and concentrations rise with downstream distance. The piston effect of vehicles can alone provide 25%-34% dilution of air pollutants in the tunnel, compounded 43%-70% dilution effect according to the ventilation condition.

Air Pollutants↗
PubMed2006

Assessment of heavy metal pollution of the Iture estuary in the central region of Ghana.

A detailed study has been presented on heavy metal content of the Iture Estuary. Waters of the Sorowie and Kakum rivers that supply water into the Estuary were investigated to ascertain heavy metal pollution levels due to anthropogenic activities. Concentration s of Cd, Zn, Se and Pb were measured. The study shows pre-occupying pollution levels that constitute a threat to both terrestrial and aquatic ecosystems. The abundance of metals in the Estuary is in the order Zn > Pb > Cd > Se. The level of Cd in the Iture Estuary ranged between 0.011 mg/l and 0.041 mg/l while Se was in the range 0.018 mg/l to 0.029 mg/l, Pb 0.020 mg/l to 0.075 mg/l and Zn 0.040 to 2.45 mg/l. The impact of contaminated water from the Sorowie River on the Iture Estuary was outstanding and the study points out the importance of the Sorowie River as a primary pollution source to the Iture Estuary. The pollution of the Iture Estuary was found to be connected to human activities in its catchments.

Agrochemicals↗
PubMed2001

The interaction between particulate air pollution and allergens in enhancing allergic and airway responses.

Although the detrimental effects of air pollution on human health have been brought widely to public notice, it appears that less attention has been given to the potential role of toxic air pollutants in the induction of allergic conditions such as asthma, rhinoconjunctivitis, and atopic eczema. A number of large epidemiologic studies have shown that people exposed to intense motor vehicle traffic and its associated emissions are at major risk for allergic symptoms, reduced lung function, and increased sensitization to common airborne allergens. Several laboratory-based studies have demonstrated that particulate air pollutants emitted from motor vehicles can induce allergic inflammation, enhance IgE responses, and increase airway hyperresponsiveness, which could provide an underlying mechanism for the increasing prevalence of allergic diseases. This article reviews the evidence that supports the causative link between particulate air pollution and the sharp increase in the prevalence of type I allergies in developed countries.

Air Pollution↗
PubMed2003

Air pollution: the "Heart" of the problem.

Air pollution exposure is associated with an increased risk of acute and chronic cardiovascular mortality. Recent observations have implicated fine particulate matter (PM(2.5)) as one of the most important pollutants. Inhalation of PM(2.5) causes acute pulmonary inflammation and oxidative stress. The subsequent generation of a systemic inflammatory response could link air pollution exposure with the development of cardiovascular disease. Human experiments have demonstrated pro-arrhythmic alterations in cardiac autonomic tone, increased blood pressure, higher serum C-reactive protein levels, and alterations in blood rheology favoring coagulation following controlled pollution exposures or in relation to elevated ambient PM(2.5) levels. Recent studies have also uncovered several harmful impacts on the systemic vasculature, including the triggering of acute vasoconstriction and the enhanced development of atherosclerosis. Many questions, however, remain unanswered and future studies will be required to clarify the relevant biologic mechanisms and to identify the specific constituents responsible for mediating the adverse health impacts.

Air Pollutants↗
PubMed1977

Detection of mutagenic activity in particulate air pollutants.

Ames's strains of Salmonella typhimurium were used to evaluate the mutagenic activity of airbone particulate materials collected at six different points in the industrial area of Ohmuta and the residential area Fukuoka. Tests were done in presence of rat-liver S-9 fraction isolated from rats that had been treated with Aroclor 1254. When the number of revertant colonies per plate was plotted against the amount of methanol extract of particulate air pollutants, using strain TA98, approximately linear relationships were observed for active samples. Generally, mutagenic activity of the samples increased in proportion to the density of air pollutants. In our system, 38--349 microng of methanol extract, from 0.225--4.51 m3 of air from the factory districts in Ohmuta City gave 100 his+ revertants per plate. On the other hand, 54--2300 microng of air pollutants, from 1.29--14.1 m3 of air from the residential districts in Fukuoka City, gave a comparable activity. Every sample from each area had mutagenic activity. Chemicals in air pollutants were fractionated by alumina column chromatography and identified by gas chromatography and mass spectrometry. More than 28 compounds, including 12 unknown substances were identified as polycyclic hydrocarbons. Twelve of these compounds are already known to be carcinogens and to induce reversions to histidine independence in strain TA98 of Salmonella.

Air Pollutants↗
PubMed1985

A hybrid model for predicting the distribution of pollutants dispersed from line sources.

This paper applies a hybrid modeling methodology to the problem of the dispersion of pollutants from line sources. The model combines a deterministic component, the GM model (Chock, 1978), with a statistical component, the two-parameter Weibull distribution, to produce estimates of the entire distribution of pollutant concentration. The approach is demonstrated using hourly average carbon monoxide data recorded in Melbourne, Australia. Using a second data set a model validation exercise is performed. The hybrid model has worked well, producing estimates of pollutant concentration with an accuracy better than a factor of two over all percentiles of the distribution of pollutant concentration.

Air Pollutants↗
PubMed1990

Phosphorus fertilizer production as a source of rare-earth elements pollution of the environment.

This paper considers some features of the production of phosphorus fertilizers in relation to pollution of the environment by rare-earth elements by measuring the change in the rare-earth elements interrelationship in snow. The main source of the pollution is identified. The distribution of pollutants is dependent on the size of the associated aerosol particles. We also report data on the concentrations of the pollutants in agricultural plants, employees' hair and hair of local residents.

Agriculture↗
PubMed1991

Socioeconomic development and environmental pollution in Hong Kong--risks and opportunities.

In the process of industrialization, Hong Kong has created an ever deteriorating environment. The increase in GDP is paralleled by a corresponding surge in the quantity of pollutants generated. Government initiatives to assess the gravity of the problem and to protect the environment began in the 1970s. The fear that too stringent control of the environment may stifle the industrial and business sectors has resulted in ineffective policies and inadequate environmental protection. Presently, Hong Kong is faced with poor air quality in most urban areas, streams polluted by livestock waste, beaches with excessive bacterial and toxic chemical concentrations, land pollution resulting from lack of space for solid waste disposal, and a high noise level from road traffic, construction and, in particular, aircraft traffic because of the location of the airport in the midst of a residential and industrial district. In a recent White Paper, Government outlined the new strategies to combat environmental pollution, which include a restructuring of the policy branch on environmental issues under the scope of planning and land use, upgrading of the sewage system, relocation of the airport, and the reduction of the sulphur content of industrial fuel. In the years ahead, Hong Kong is faced with new challenges. Environmentally, the commissioning of the nuclear plant at Daya Bay poses a risk of ionizing radiation. The construction of the new airport, together with extensive reclamation of the harbour and expansion of seaport facilities, will create changes in the tidal flow and the ecological system. The negative effects on the environment must be considered together with the potentially beneficial effects, economical and environmental. To achieve maximum impact in environmental protection, community participation is essential. To this end, education on the conservation of the environment should be expanded and specially targeted at schoolchildren, in whom environmental education has been neglected.

Environmental Pollution↗
PubMed1993

[Exposure of urban bus drivers to traffic pollution].

Two measurement campaigns aimed at measuring the air pollutant emissions of vehicles (carbon monoxide, nitrogen oxides, lead, benzo[a]pyrene and formaldehyde) have been carried out using on-board sampling or analysis equipment in public buses in two major French towns. The study had a double objective: (i) to assess the occupational exposure through pollutant measurements in the breathing zone of the drivers at their working posts, (ii) to compare the quality of the air sampled outside, either at the bus front (current position of the ventilation air intake), or on the vehicle roof. Carbon monoxide measurements were performed with several Ecolyser (electrochemical detection) standardized with a Mahiak Unor 6N infra-red non-dispersive analyser and nitrogen mono- and dioxide with AC 30 M Environment S.A. analysers (chemiluminescent detection), with a data-logger recording the '5-min weighted average concentrations'. Lead on dust was sampled on cellulose acetate or quartz filters and analysed by atomic absorption, benzo[a]pyrene (as a tracer of polynuclear hydrocarbons) on quartz filters and by HPLC/UV fluorescence detector and formaldehyde (as a tracer of aldehydes) on 2,4-DNPH-impregnated silicagel tubes by HPLC/UV. Recording and sampling were performed for 18 single and return routes in the center of Paris (for 1.5-2 h each) and for 25 routes in the center of Bordeaux (for 35-60 min). The results clearly indicate that the occupational exposures of urban bus drivers for the six pollutants are lower than the exposure limit values in the working place (French Labour Department or A.C.G.I.H. standards). In particular, levels for benzopyrene, associated with carcinogenic hazard, do not increase 5% of the standard from Russian origin (150 ng/m3). On the contrary, concentrations reached the levels recommended by international air quality standards (OMS, US or European standards) for carbon monoxide, nitrogen dioxide and lead. When CO mean concentration values by bus lines in the driver's breathing zone are compared with the measurement results provided for the same sample days by the Air-Parif control network (in Paris), or the Gertrude traffic management system (in Bordeaux), it may be assumed that they are at the level of the most polluted surveillance stations. The CO concentrations are significantly lower in the outdoor air coming from the roof than in that coming from the front of the bus, so that better indoor air quality at the driving post can be found with air intake from an upper than a lower part.

Air Pollutants↗
PubMed1993

A model for car exhaust exposure calculations to investigate health effects of air pollution.

This paper presents a model for car exhaust exposure calculations, which improves the air pollution exposure estimates necessary to study relationships between health and air pollution. The model enables calculation of hour-by-hour air pollution concentrations at receptor points in an area. Combined with a diary method, in which participants in the study give data on their movement in the area, the model enables personal air pollution exposure values to be calculated. The paper shows examples of comparison between measured and calculated exposure.

Air Pollutants↗
PubMed1995

Perceived traffic air pollution, associated behavior and health in an alpine area.

The relationship of traffic air pollution, perception of exhaust fumes/soot and behavioral impact or symptoms/illnesses was investigated in two surveys (adults: aged 25-65, N = 1989, 62% participation; children: aged 8-12, N = 796, 85% participation) in 13 small alpine communities (Tyrol/Austria) by means of questionnaire responses and air pollution measurements. Although pollutant levels complied with current WHO guidelines, adult respondents felt annoyed by odourous traffic fumes (39.7%) or visible dust/soot (26.9%). Logistic regression analysis revealed that accompanying noise annoyance, rated impairment of life quality, protesting behaviour, noise- and odour-sensitivity was directly associated with perceived air quality, while age above 45 years, smoking, and social support was inversely associated with perceived air quality. Among the symptoms, feelings of fatigue/exhaustion/low mood/nervousness and irritation of the eyes and stomach aches showed a significant association with rated air quality. Children in the traffic exposed areas spend less time outdoors and reported perception of car fumes was significantly associated with recurrent colds, chronic bronchitis and an index of hyperreactive airways. Measured indices of pollution (traffic counts, NO2) were not associated with any of the children's reported illnesses.

Adult↗
PubMed1992

Air pollution and infant mortality in the Czech Republic, 1986-88.

An ecological study of infant mortality and air pollution was conducted in the Czech Republic. Routinely collected data on infant mortality and air pollution in the period 1986-88 were analysed for the 46 of the 85 districts in the republic for which both were available. The independent effects of total suspended particulates (TSP-10), sulphur dioxide (SO2), and oxides of nitrogen (NOx) adjusted for district socioeconomic characteristics, such as income, car ownership, and abortion rate, were estimated by logistic regression. We found weak positive associations between neonatal mortality and quintile of TSP-10 and SO2. Stronger adjusted effects were seen for postneonatal mortality, with a consistent increase in risk from the lowest to the highest TSP-10 quintile (p < 0.001). Weaker and less consistent evidence of a positive association with NOx (p = 0.061) was observed. The strongest effects were seen for postneonatal respiratory mortality, which increased consistently from lowest to highest TSP-10 quintile (p = 0.013). There was also a suggestion of a positive association with SO2 (p = 0.062). The highest to lowest quintile risk ratios for postneonatal respiratory mortality were 2.41 (95% Cl 1.10-5.28) for TSP-10, 3.91 (0.90-16.9) for SO2, and 1.20 (0.37-3.91) NOx. The specificity of the association between air pollution quintile (especially TSP-10) and postneonatal respiratory mortality is consistent with the known effects of air pollution on respiratory disease morbidity in children. These ecological associations require confirmation in an individually based study.

Abortion, Legal↗
PubMed1990

Cytogenetic investigation in lymphocytes of people living in cadmium-polluted areas.

Chromosome aberrations were analyzed from peripheral lymphocyte cultures of 21 men and 19 women who had been exposed to environmental cadmium, and 11 controls (9 men and 2 women). The average cadmium level in the urine of the Cd-polluted group was 3.32 micrograms/l for men and 3.83 micrograms/l for women. There were significant differences in chromosome aberration frequencies between the Cd-polluted and non-polluted groups. The number of individuals with relatively high aberration frequencies (greater than or equal to 5%) in the Cd-polluted group was greater than in the controls. Individuals with a high cadmium content in urine (greater than or equal to 3 micrograms/l) had higher aberration frequencies and more severe aberration types in comparison with the low-cadmium group (less than 3 micrograms/l). There were significant correlations between chromosome aberration frequencies and urinary cadmium content (r = 0.463). The linear regression equation was determined. Considering the conflicting results in other published reports, it is hard to say that the conclusion that cadmium only acts synergistically to enhance the mutagenicity of other compounds present in the environment is correct. According to our study, environmental cadmium cannot only induce chromosome aberrations but also increases the chromosomal aberration frequencies and the frequency of severe aberration types.

Adult↗