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  A PRELIMINARY EVALUATIONOF SELECTEDTRANSPORT-RELATEDPOLLUTANTSIN THE AMBIENTATMOSPHERE OF THE CITY OF BEIRUT, LEBANON F. B. CHAABAN 1 ∗ , G. M. AYOUB 1 and M. OULABI 21 Faculty of Engineering and Architecture, American University of Beirut, 850 Third Ave, New York, NY 10022, U.S.A.; 2  Lebanese Atomic Energy Commission, National Council for Scientific Research Beirut, Lebanon( ∗ author for correspondence, e-mail: fbchaban@aub.edu.lb; fax: 9611744462) (Received 1 December 1999; accepted 21 February 2000) Abstract. Particulate matter is emitted to the atmosphere from various energy conversion processes,mainly from the electric power and the transportation sectors. Recent studies and peer reviews con-ducted by international organizations have indicated the adverse health and economic effects of theaccumulation of these particulates in the environment. In the absence of any data related to the levelsof air pollution in the Beirut environment, this study was initiated with the objective of conductinga preliminary investigation that includes air sampling and the X-ray fluorescence analysis of thesamples. Emphasis is placed on the impact of the transport sector on the dissemination of differentpollutants and in particular lead. The results show high levels of particulates resulting from differentsources and high concentrations of lead within the city of Beirut. A direct correlation between theparticulate constituents and street activities is identified. The results indicate the seriousness of theair pollution problem that the transport sector can inflict on the society if appropriate mitigativemeasures are not implemented, especially in urbanized regions where traffic flow is consistentlyheavy. Mitigation options applicable to Lebanon and possibly to other countries of similar economicand social structure are recommended. Keywords: air pollution, lead emissions, policy options, transport, X-ray spectrometry 1. Introduction The impact of air pollution on the environment is reaching dangerous levels world-wide. Some of the major sources of this pollution include energy conversion sys-tems, where electric power generation and transportation systems are the majorcontributors. Transportation systems have various socio-economic benefits and sig-nificant impacts that mayvary from one country to another. However, these systemshave undesirable impacts on the environment since, in addition to the noise theygenerate, motor vehicles produce emissions that are detrimental to the environmentand health. The transport sector has been globally witnessing a continuous growthsince the turn of the century. It is estimated that up to 37% of the total world energyconsumed is used in transport and up to one third of air pollution is caused by thissector (Hein, 1995; Chaaban, 1995). The extent to which emissions from thesesources are controlled will largely dictate the extent of environmental pollution. Water, Air, and Soil Pollution 126: 53–62, 2001.© 2001 Kluwer Academic Publishers. Printed in the Netherlands.  54 F. B. CHAABAN ET AL. The levels of air pollutants in Lebanon and specifically in the capital city of Beirut, where about 40% of the country’s population dwell, have been increasingat alarming rates. The health of the inhabitants is becoming a concern. Beirut, witha population of about a million and a half, is more frequently experiencing episodesof photochemical smog formations. Detailed measurement of the composition andconcentrations of the causing pollutants have not been carried out to date, however,these episodes are visible and their health effects are widely experienced. In theabsence of heavy industry in Lebanon, the transportation sector is regarded as themain source that is contributing to air pollution.This study covers a preliminary evaluation of emission levels in the city of Beirut of some of the pollutants that are transport related including particulatematter and lead, and from other sources such as iron, copper, calcium, and others.Options for mitigation will be discussed and presented as part of the study. 2. The Lebanese Transport Sector The one and a half decades of civil strife in Lebanon has had a negative socio-economic impact on population and organizations, both private and public. Amongthe various sectors that were seriously affected was the transportation sector (Chaa-ban, 1998). Itunderwent major changes in theform ofthe car that wasplaced on theroad, the fuel used, and the lack of effective control by the authorities. To cater forthe limited financial income of the population, used imported cars became the mainsource of car supply. The door was wide open to the import of used cars where everfound with no restriction placed on car model (recently car model for imported carswas limited to a maximum of eight years) nor on mechanical condition. Availabledata indicate that about 70% of the private cars in Lebanon are of the 1984 model orolder. To compensate for the breakdown in the public transport system, the numberof private cars escalated to levels that are now considered, on a per capita basis,amongst the highest recorded worldwide. Table I shows the population figuresand levels of private car ownership rates in some countries compared to those inLebanon. It is also estimated that 291 000 cars are owned by residents of Beirut andabout 200 000 cars from other parts of the country commute in and out of Beirutevery twenty-four hours (TEAM, 1994). One and a half million motorized tripstake place within the city on a daily basis out of which 70% are made by privatecars. It is expected that the number of motorized trips will grow to five million inthe year 2015.Moreover, very loose regulations were established for the import of fuel in thatlead-laden fuels with high sulfur contents were imported and distributed. It is es-timated that about half of the fuel consumed in the transport industry is consumedin the city of Beirut. This could amount to about 700 000 tons per day. Only sixyears ago unleaded gasoline was introduced in Lebanon. However, leaded fuel stillforms the bulk on the market. Statistics (CBL, 1998) show that imported unleaded  A PRELIMINARY EVALUATION OF SELECTED TRANSPORT-RELATED POLLUTANTS 55 TABLE IPopulation and car ownership figures in some countriesCountry Population ( × 10 6 ) persons/carEgypt 65 90France 59 2.35Greece 10.5 4.8Indonesia 195 93Japan 125 2.85Kuwait 1.85 3.4Lebanon 3.7 3.35Morroco 28 37Nigeria 96 145Turkey 63 20U.S.A. 268 2Venzuela 23 15 Figure 1. Transport fuel imports to Lebanon. fuel formed 6% in 1995 and 15% in 1998 of the total imported fuel, (Figure 1).As a result of the lead emissions, the local inhabitants suffer from excessive leadlevels in the blood. Studies (Nuwayhid, 1997) based on blood sampling in Beiruthave indicated that 86% of those sampled have lead levels greater than 10 µ g dl − 1 ,the limit globally recommended for children (EPA, 1997). The results also showedthat 44% of the samples had lead levels exceeding 16 µ g dl − 1 .Installation of pollution control equipment in cars was never legislated for,neither was routine engine and mechanical inspection enforced by the authorit-ies. Under the present conditions, it would be justifiable to classify the transport  56 F. B. CHAABAN ET AL. system in Lebanon as one that is operating under uncontrolled conditions and thecontribution of pollutants from this sector is thus at its peak.The relatively narrow streets and the high buildings bounding these streets, anurban feature that is characteristic to the city of Beirut, lead to deficient ventilationand to increasing pollutant concentrations emitted from vehicular traffic. 3. Experimental Work 3.1. S AMPLING STRATEGIES Particulates in the urban atmosphere result from different sources including airborn dust transported from areas away from the zone of measurement, industrialsoot emissions, and vehicular emissions. Separation of these sources is practicallyimpossible. As the purpose of the study was to evaluate the levels of some pol-lutants related to particulate matter emitted from the transport sector, the choiceof a sampling location isolated from any industrial pollutant was needed. With thisobjective, a main one-way street (Bliss Street) was selected in Ras Beirut area. Thisstreet is classified as a heavy traffic street which caters for passengers commutingto the American University of Beirut (AUB), two major high schools, residentialbuildings and partly to one of the major shopping districts in the city.The sampling station was set at the side terrace of an AUB building and waslocated at a distance of about five meters from the side of the street and an elevationof about three meters from the street level. Sampling was designed for pumpingambient air through filters on a 24-hourly basis. For more detailed analysis, hourlysamples were collected in certain cases.3.2. A NALYTICAL TECHNIQUES A calibrated Graseby GL2000H total suspended particulates (TSP) sampling unitwas used for the sampling process. This high- volume sampler has an air flowrate range from 20 to 60 CFM. It utilizes a heavy duty turbine blower and highspeed motor for 24-hr continuous sampling. The G810 glass fiber filters used in thesampling were replaced on a daily basis. The filters were weighed before and aftersample collection in order to determine the amount of particulate matter collectedfrom the ambient air. Particulate concentrations were established after assessingthe air volume that passed through the filter.Qualitative and quantitative measurements of heavy metals were conducted us-ing the energy dispersive X-ray fluorescence technique (EDXRF). Each samplewas divided into four sub-samples by cutting the filter paper into four sectionsin accordance with the sample holder diameter (25 mm). The sub-samples werepresented directly to the unit with the loaded side directed towards the EDXRFinstrument. The spectrum for each sub-sample was obtained after the laps of 5000son the instrument. Each spectrum was analyzed quantitatively by identifying the
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