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[Pollution of operating rooms with volatile and gas anesthetics. Methods of prevention].

Gaseous anaesthetic pollution in operating theatres has been known since as far back as 1924. Following Vaisman and Cohen's epidemiology studies, health organizations have been involved in this professional concern. Halogenated vapours and nitrous oxide anaesthetic pollution have been accused of doubling the abortion rate and of moderately increasing the number of congenital abnormalities in the offsprings of anaesthetists. The liver and nervous system are also likely targets for anaesthetic pollution. Animal or cell culture experimental studies concerning pathological consequences of exposure to nitrous oxide or halogenated vapours give conflicting results and are not conclusive. The pollution rate is measured by chromatography and spectrophotometry. 25 ppm nitrous oxide and 2 ppm halothane are the upper limits allowed for air contamination. Total intravenous anaesthesia, closed circuits, draining away expired gases can prevent such pollution, but these techniques do have drawbacks. Pollution prevention is rather simple, moderately expensive and comforting for operating room staff.

Air Pollution↗

[The impact of air pollution on health. The "Programme de Surveillance Air et Santé 9 villes" (Air and Health surveillance program in 9 cities)].

OBJECTIVES: To quantify the short term effects of air pollution on mortality and hospitalisation for cardiovascular or respiratory disorders in the nine French cities (Bordeaux, Le Havre, Lille, Lyon, Marseille, Paris, Rouen, Strasbourg and Toulouse) of the Surveillance Air et Santé program. METHODS: Data were available on mortality and hospitalisation were available, respectively, from 1990 to 1997 and 1995 to 1999. Exposure data were the concentrations of sulphur dioxide, particles with a diameter of less than or equal to 10 mm, black smoke, nitrogen dioxide, ozone, and carbon monoxide. The analysis assessed the relationships, in each of the cities, between the daily numbers of deaths and hospitalisations and the daily levels of polluting agents, taking into account confounding factors. A combined relative risk was calculated for all the cities. The number of deaths and hospitalisations attributable to air pollution was then estimated for each of the cities, based on the relative risk. RESULTS: Significant relationships were found for mortality, from whatever cause, and for hospitalisations for respiratory disorders in children aged under 15. If the levels of air pollution were reduced to 10 microg/m3 in the nine cities, 2800 premature deaths and 750 hospitalisations for respiratory disorders in children would be avoided, every year. CONCLUSION: Today, it is possible to assess the benefits of reducing air pollution in terms of health in the short term. These analyses would provide a sanitary dimension to the strategies for the reduction of urban pollution on local and European level.

Adolescent↗

Atmospheric pollution and the prevalence of asthma: study among schoolchildren of 2 areas in Rio de Janeiro, Brazil.

BACKGROUND: Air pollutants have been associated with the exacerbation of respiratory diseases. They may intensify the inflammatory allergic response and airways reactivity to inhaled allergens. However, it is still not clear if air pollution contributes to the increased prevalence of asthma. OBJECTIVE: To investigate if different levels of air pollution exposure can be related to differences in the prevalence of asthma. METHODS: The International Study of Asthma and Allergies in Childhood (ISAAC) protocol was used to determine and compare the prevalence of asthma among schoolchildren in 2 cities of the metropolitan region of Rio de Janeiro, Brazil, Duque de Caxias (DC) and Seropédica (SR), which have different levels of atmospheric pollution. The research involved 4,064 students aged 13 to 14 years from 49 schools in DC and 1,129 from 17 schools in SR. Air pollution was evaluated by the concentration of inhalable particulate matter (PM10). RESULTS: ISAAC's written questionnaire was answered by 4,040 students aged 13 to 14 years in DC and 1,080 in SR. Between 1998 and 2000, the PM10 annual arithmetic mean was 124 microg/m3 in DC and 35 microg/m3 in SR (acceptable level is up to 50 microg/m3). The prevalence of wheezing ever was 35.1% in DC and 29.9% in SR (P = .001), and the prevalence of wheezing in the last 12 months was 19.0% in DC and 15.0% in SR (P = .002). In DC, 14.5% of the adolescents presented 1 to 3 crises of wheezing in the last year, whereas in SR only 11.0% presented 1 to 3 crises (P = .003). CONCLUSIONS: In this study, the prevalence of asthma in adolescents was directly related to atmospheric pollution.

Adolescent↗

Air pollutants enhance rhinoconjunctivitis symptoms in pollen-allergic individuals.

BACKGROUND: Little is know about the relation of airborne pollen allergens to nasal and ocular symptoms in combination with air pollutants. OBJECTIVE: The hypothesis was that air pollutants exacerbate allergic symptoms of the nose and eyes during the pollen season. In addition, the use of allergen measurements instead of pollen counts should be tested. METHODS: Fifteen pollen-allergic, nonsmoking subjects with weak reactivity of the airways recorded rhinoconjunctival symptoms and medication every morning and evening throughout the pollen season. Symptoms were compared with air pollutants (nitrogen oxide [NOx], particulate matter smaller than 10 microm, and ozone) and birch and grass pollen counts or, alternatively, to airborne birch and grass allergens determined using ELISA-techniques. A multiple linear regression model was used which controlled for autocorrelation of the residuals of the time series (Cochrane-Orcutt approach). This model was applied to each subject individually, followed by calculations of summary scores for the group. RESULTS: Air pollution levels were moderate, often meeting air quality standards. Effect estimates (increase of score with 10-fold increase of concentration) were NOx = 1.06, P < 0.01; ozone = 1.59, P < 0.01; and pollen = 0.48, P < 0.001. Using allergen concentrations instead of pollen counts resulted in similar effect estimates. Using particulate matter smaller than 10 microm instead of NOx gave comparable but less consistent results. CONCLUSIONS: Symptoms were related to moderate levels of pollutants, suggesting that rhinoconjunctival tissue is very sensitive to irritant stimuli during an ongoing allergic inflammation, and that susceptibility toward allergens might be increased in areas with increased levels of air pollutants. Allergen measurements seem equally usable as pollen counts to investigate rhinoconjunctivitis.

Adult↗

Mutagenicity of sediments along the Po River and genotoxicity biomarkers in fish from polluted areas.

We monitored the mutagenicity of extracts of sediment fine particles collected, both in the cold season and in the hot season, from 10 reaches along the Po River, the main Italian watercourse. Each sample was representative of several kilometers of river stretch. At sub-toxic doses, the samples were not mutagenic to the Salmonella typhimurium his(-) strains TA98, TA100 and TA102, irrespective of the presence of S9 mix. However, they induced a mutagenic response in YG1024, which is typically reverted by frameshift mutagens that are metabolized in bacteria via acetyl-CoA:N-hydroxylamine O-acetyltransferase. Mutagenicity of sediments was higher during the cold season and had a spatial distribution consistent with the occurrence of pollution sources and confluence with polluted tributaries. Nevertheless, in the final stretch, near the Po delta into the Adriatic Sea, mutagenicity of sediments was low, comparable to that detected in the Po proximal reach, not far away from its springs. Genotoxicity biomarkers were evaluated in three cyprinid species, the "Italian nase" (Chondrostoma söetta), chub (Leuciscus cephalus), and barbel (Barbus plebejus), captured upstream and downstream of the confluence of a polluted tributary (Lambro River) with the Po River. There was no difference between the two areas concerning concentrations of fluorescent aromatic compounds in fish bile while, after metabolic activation, the bile of fish caught from the more polluted area became mutagenic to YG1024. Moreover, the levels of adducts to liver DNA were significantly higher in L. cephalus caught from the more polluted area, and the increase of micronucleated erythrocyte frequency was borderline to statistical significance, but only in C. söetta. Thus, certain biomarkers of exposure and effect in fish, as assessed under field conditions, correlate with the pollution of river sediments by mutagenic compounds.

Animals↗

Effects of heavy metal pollution on swimming and longevity in cercariae of Cryptocotyle lingua (Digenea: Heterophyidae).

Effects of heavy metal pollution on the cercariae of the marine trematode Cryptocotyle lingua (Creplin) were studied by measuring horizontal swimming rate (HSR) and longevity. These factors are important for transmission to the next host, a fish. Cercariae released by Littorina littorea (L.) collected from polluted and unpolluted sites were compared. Both HSR and longevity were significantly reduced in cercariae from the polluted environment. Cercarial quality was therefore reduced, directly or indirectly, by development within a metal-accumulating host. Cercariae released by hosts from a clean environment were subjected to nominal concentrations of 2 and 3 mg/l copper, 1 and 2 mg/l zinc, 2 and 5 mg/l iron and 2 and 4 mg/l manganese in artificial seawater. In all cases the HSRs and longevity were reduced. The effect was more pronounced in the higher concentrations. The significant HSR tests indicate that the absorption and effect of metals occurred within 1 min. The cercarial tegument, specialized for absorption in endoparasitic environments, is possibly responsible. Cercariae may therefore be excellent indicator organisms for pollution. The pollution-induced reductions in cercarial quality seem capable of producing transmission failure. Heavy metal pollution could therefore alter parasite populations and communities.

Animals↗

Magnetic response of soils and vegetation to heavy metal pollution--a case study.

Fast and cost-effective detection of industrial pollution can significantly promote its ecological, economic, and social assessment. A magnetometric method, used for qualitative determination of anthropogenic contamination, meets these requirements but needs further development in more quantitative terms. It could be used successfully in numerous cases when the heavy metals coexist with strongly magnetic iron oxide particles in the source dust. We present an integrated magnetic and geochemical study that examines the utility of magnetometric techniques for rapid, qualitative detection of metallic pollutants in soils and vegetation. The new aspect of our approach, in comparison with previously published articles on this subject, is the combined investigation (magnetic and geochemical) of both soils and vegetation, thus using an additional medium for employing the magnetometry as a pollution proxy at a site. The study area is a small (approximately 3 km2) region in the suburbs of Sofia (Bulgaria), with the main pollution source being a metallurgical factory. Soil samples have been taken from the topmost 20 cm from private gardens, located at different distances from the factory. Vegetation samples were taken from ryegrass (both leaves and roots) and leaves from two kinds of deciduous trees (maple and acacia). The results show that both vegetation and soils are characterized by enhanced magnetic properties, compared to background material, which is due to the presence of magnetite particles of anthropogenic origin accompanying heavy metal emissions. SEM images and microprobe analyses reveal the presence of a significant amount of particles, containing heavy metals (including iron) in vegetation samples taken close to the main pollution source. Correlation analyses show a statistically significant link (correlation coefficients ranging from 0.6 to 0.7) between magnetic susceptibility and the main heavy metals (Cu, Zn, Pb) in soil samples, indicating that the magnetic susceptibility can provide a proxy method for identifying the relative contribution of industrial pollution in soils and vegetation, that is reliable, inexpensive, and less time-consuming than standard chemical analyses.

Environmental Monitoring↗

Intercontinental transport of air pollution: will emerging science lead to a new hemispheric treaty?

We examine the emergence of InterContinental Transport (ICT) of air pollution on the agendas of the air quality and climate communities and consider the potential for a new treaty on hemispheric air pollution. ICT is the flow of air pollutants from a source continent (e.g., North America) to a receptor continent (e.g., Europe). ICT of air pollutants occurs through two mechanisms: (i) episodic advection and (ii) increasing the global background, which enhances surface concentrations. We outline the current scientific evidence for ICT of aerosols and ozone, both of which contribute to air pollution and radiative forcing. The growing body of scientific evidence for ICT suggests that a hemispheric-scale treaty to reduce air pollutant concentrations may be appropriate to address climate and air quality concerns simultaneously. Such a treaty could pave the way for future climate agreements.

Aerosols↗

Gaseous elemental mercury in the marine boundary layer: evidence for rapid removal in anthropogenic pollution.

In this study, gas-phase elemental mercury (Hg0) and related species (including inorganic reactive gaseous mercury (RGM) and particulate mercury (PHg)) were measured at Cheeka Peak Observatory (CPO), Washington State, in the marine boundary layer during 2001-2002. Air of continental origin containing anthropogenic pollutants from the urban areas to the east contained on average 5.3% lower Hg0 levels as compared to the marine background. This result is difficult to reconcile since it is known that industrial emissions in our region are sources of Hg0. The rate of removal of Hg0 from a pollution plume necessary to account for our observations is inconsistent with the accepted view of Hg0 as a stable atmospheric pollutant. The largest and most frequent Hg0 loss events occurred in the presence of increased ozone (O3) during the summer. Hg0 and O3 also display diurnal cycles that are out-of-phase with one another. In other seasons Hg0 behavior is less consistent, as we observe weak positive correlations with O3 and occasional Hg0 enhancements in local pollution. RGM and PHg concentrations are enhanced only slightly during Hg0 loss events, comprising a small fraction of the mercury pool (approximately 3%). Long-range transported pollution of Asian origin was also detected at CPO, and this contains both higher and lower levels of Hg0 as compared to the background with maximum changes being <20%. Here, the more photochemically processed the air mass, as determined by propane/ethane ratios, the more likely we are to observe Hg0 loss. Air from the marine background in summer displays a significant diurnal cycle with a phase that matches the diurnal cycles seen in polluted air masses. A Junge lifetime for Hg0 in the clean marine boundary layer is calculated to be 7.1 months, which is on the low end of previous estimates (0.5-2 yr).

Air Pollutants↗

Dispersion of heavy metals (metalloids) in soils from 800-year-old pollution (Mont-Lozère, France).

Numerous palaeo metallurgical sites (n = 70) characterized by slag presenting a homogeneous typology have been reported on the Mont-Lozère Massif (Southern France). These activities took place in the medieval period. The silicated slag matrix comprises mainly Pb (25%), Sb (0.4%), and several thousand parts per million of As, Cu, and Zn. Soil samples were collected in and around two sites, to understand the dispersion mechanism affecting the slag tailings through use of metal concentrations and lead isotopic compositions. The majority of polluted soil samples show high enrichment factors (EF) for Pb and Sb, slightly lower EFs for Cu, and much lower EFs for As and Zn. We show that this "old" metal pollution was physically dispersed, through erosion of workshop soils and slag tailings, in a restricted area (ca. 200 m down slope form the site). There is no evidence for massive leaching of slag metals by soil waters, except for Zn. Thus, the pollution is mainly due to the metal-making process, i.e., smoke-fallout, pieces of ore, the crackling of smelting ore outside the oven during reduction, and charcoal, etc. The lead isotopic compositions of the soils define a binary mixing trend between local granite or background soil and slag (which represent the workshop soil). Simple mass balance equations using either Pb isotopes or Pb concentrations suggest that between 40 and 100% of the total Pb in soils comes from the Medieval workshop pollution, leaving any later pollution negligible. The large number of sites on the Mont-Lozère means this medieval pollution is significant and poses a real environmental risk.

France↗

Environmental urban factors (air pollution and allergens) and the rising trends in allergic respiratory diseases.

Respiratory allergic diseases such as rhinitis and bronchial asthma appear to be increasing worldwide, affecting in particular subjects living in urban areas, and the reasons for this increase are still largely unknown. Although the role played by air pollution has yet to be clarified, a body of evidence suggests that urbanization, with its high levels of vehicle emissions and a westernised lifestyle are linked to the rising frequency of these diseases observed in most industrialized countries. Laboratory studies confirm the epidemiological evidence that inhalation of some pollutants, either individually or in combination, adversely affect lung function in asthmatics. Air pollutants may not only increase the frequency and intensity of symptoms in already allergic patients but may promote airway sensitization to airborne allergens in predisposed subjects. By attaching to the surface of pollen grains and of plant-derived paucimicronic particles, pollutants can modify the morphology of these antigen-carrying agents and alter their allergenic potential. In addition, by inducing airway inflammation, pollutants may overcome the mucosal barrier and so "prime" allergen-induced responses. In other words airway mucosal damage and impaired mucociliary clearance induced by air pollution may facilitate the access of inhaled allergens to the cells of the immune system.

Air Pollutants↗

The relative importance of socio-economic status, parental smoking and air pollution (SO2) on asthma symptoms, spirometry and bronchodilator response in 11-year-old children.

The aim of this study was to evaluate the relative contribution of several risk factors to the prevalence of allergic respiratory symptoms, and the positivity of the bronchodilator test with fenoterol, and to establish the relative importance of these factors on the variability of FVC, FEV1, PEF, MEF25, MEF50 and MEF75. A total of 340 11-year-old children attending school in polluted and non-polluted areas of the city of Cartagena, Spain, were studied. The polluted area had had an annual mean of 75 microg/m3 of SO2 over the last 10 years and the non-polluted area had < 20 microg/m3 during this period. A questionnaire about allergic respiratory symptoms was completed by the parents. Specific questions about parental smoking habits and socio-economic level were included. Each child's performance in spirometry before and after administration of 0.2 mg of inhaled fenoterol was evaluated. The only significant predictive variables in the logistic regression (for suffering any symptom or a positive bronchodilator response) were male sex for nasal symptoms (RR 1.37; p = 0.04) and housing near heavy traffic for eye symptoms (RR 1.45; p = 0.01). Living in the polluted area reduced the risk of a positive bronchodilator response (RR 0.61; p = 0.004). Maternal smoking, even though not statistically significant, tended to increased the risk of suffering any symptom (RR 1.26; p = 0.07) or of having a positive bronchodilator response (RR 1.23; p = 0.1). None of the risk factors studied was of significant importance in explaining the variability of spirometry results. Although none of the risk factors were specifically determinant to the symptom questions, bronchodilator test or spirometric measurements, having a mother who smokes seems more important than living in a polluted area if statistically non-significant trends are considered.

Adult↗

Responding to sudden pollutant releases in office buildings: 1. Framework and analysis tools.

We describe a framework for developing response recommendations to unexpected toxic pollutant releases in commercial buildings. It may be applied in conditions where limited building- and event-specific information is available. The framework is based on a screening-level methodology to develop insights, or rules-of-thumb, into the behavior of airflow and pollutant transport. A three-stage framework is presented: (1). develop a building taxonomy to identify generic, or prototypical, building configurations; (2). characterize uncertainty and conduct simulation modeling to predict typical airflow and pollutant transport behavior; and (3). rank uncertainty contributions to determine how information obtained at a site might reduce uncertainties in the model predictions. The approach is applied to study a hypothetical pollutant release on the first floor of a five-story office building. Key features that affect pollutant transport are identified and described by value ranges in the building stock. Simulation modeling provides predictions and uncertainty estimates of time-dependent pollutant concentrations, following a release, for a range of indoor and outdoor conditions. In this exercise, we predict concentrations on the fifth floor to be an order of magnitude less than on the first, coefficients of variation greater than 2, and information about the HVAC operation and window position most reducing uncertainty in predicted peak concentrations.

Air Movements↗

Estimation of long-term average exposure to outdoor air pollution for a cohort study on mortality.

Recent prospective cohort studies have suggested that long-term exposure to low levels of particulate matter (PM) air pollution is associated with increased mortality due to, especially, cardio-pulmonary disease. Exposure to ambient air pollution was estimated mostly as city average concentrations, assuming homogenous exposure within the city. We used an ongoing cohort study - The Netherlands Cohort Study (NLCS) on diet and cancer - to investigate the relationship between traffic-related air pollution and mortality. The baseline data collection took place in 1986. A study was conducted to develop methods for exposure assessment and evaluate the contrast in exposure to air pollution within the cohort. Assessment of long-term exposure to two traffic-related air pollutants, Black Smoke (BS) and Nitrogen Dioxide (NO(2)), consisted of separate estimation of regional background, urban background, and local traffic contributions at the home address. Interpolation of concentration data from a routine monitoring network was used to estimate the regional background concentration. A regression model relating degree of urbanization to air pollution was used to allow for differences between different towns/neighborhoods of cities. Distance to major roads was calculated to characterize local traffic contributions, using a Geographic Information System (GIS). Interpolation resulted in reasonably precise regional background estimation when distant sites were not used and distance squared was used as the weight. Cross-validation showed that prediction errors were about 15% of the range in regional background concentration. Urban and local scales contributed significantly to the contrast within the cohort. Prediction errors for estimating the urban background were about 25% of the range in background concentrations. When the developed model was applied to the study cohort, there was substantial contrast in estimated exposure to BS and NO(2). About 90% of the study population lived 10 years or more at its 1986 home address - supporting the use of the estimated concentration at the 1986 address as a relevant exposure variable.

Aged↗

Long-term air pollution indicator assessment: example of black smoke in Bordeaux, France.

The aim of the second phase of the Pollution Atmosphérique et Affections Respiratoires Chroniques (PAARC) study, started in 1974, was to compare the long-term mortality between populations living in areas with different air pollution levels. In Bordeaux (France), four different areas were concerned by the study. The black smoke measures were realized between 1974 and 1981. After 1981, the stations set specifically for the study were not used any more. The purpose of this study was to estimate the evolution of air pollution in those areas between 1982 and 1997 using the measures of 12 Association de Prévention de la Pollution Atmosphérique (APPA) stations located in Bordeaux city but not in the PAARC areas. The method used was divided in three phases: a correlation study between the stations of the different networks, a selection of the pertinent stations and the setting up of indicators using the arithmetic means method. Monthly means concentrations were estimated from January 1982 to December 1997. Models showed a decrease in black smoke levels whatever the area. The difference in level from one area to another, existing between the areas in 1974, was still with predicted values in 1997, but less important. Black smoke mean concentration for 1982-1997 was, respectively, 16.4 and 16.2 microg/m3, in areas 1 and 2. It was a little bit higher in area 3 with 18.9 microg/m3. Area 4 still has the highest level with 26.3 microg/m3. To conclude, this method enabled to assess different air pollution levels at different times in the four areas of the PAARC study in Bordeaux. Those levels could be used to study the impact of the air pollution on long-term mortality on populations living in the areas considered.

Air Pollution↗

A pilot study using scripted ventilation conditions to identify key factors affecting indoor pollutant concentration and air exchange rate in a residence.

A pilot study was conducted using an occupied, single-family test house in Columbus, OH, to determine whether a script-based protocol could be used to obtain data useful in identifying the key factors affecting air-exchange rate (AER) and the relationship between indoor and outdoor concentrations of selected traffic-related air pollutants. The test script called for hourly changes to elements of the test house considered likely to influence air flow and AER, including the position (open or closed) of each window and door and the operation (on/off) of the furnace, air conditioner, and ceiling fans. The script was implemented over a 3-day period (January 30-February 1, 2002) during which technicians collected hourly-average data for AER, indoor, and outdoor air concentrations for six pollutants (benzene, formaldehyde (HCHO), polycyclic aromatic hydrocarbons (PAH), carbon monoxide (CO), nitric oxide (NO), and nitrogen oxides (NO(x))), and selected meteorological variables. Consistent with expectations, AER tended to increase with the number of open exterior windows and doors. The 39 AER values measured during the study when all exterior doors and windows were closed varied from 0.36 to 2.29 h(-1) with a geometric mean (GM) of 0.77 h(-1) and a geometric standard deviation (GSD) of 1.435. The 27 AER values measured when at least one exterior door or window was opened varied from 0.50 to 15.8 h(-1) with a GM of 1.98 h(-1) and a GSD of 1.902. AER was also affected by temperature and wind speed, most noticeably when exterior windows and doors were closed. Results of a series of stepwise linear regression analyses suggest that (1) outdoor pollutant concentration and (2) indoor pollutant concentration during the preceding hour were the "variables of choice" for predicting indoor pollutant concentration in the test house under the conditions of this study. Depending on the pollutant and ventilation conditions, one or more of the following variables produced a small, but significant increase in the explained variance (R(2)-value) of the regression equations: AER, number and location of apertures, wind speed, air-conditioning operation, indoor temperature, outdoor temperature, and relative humidity. The indoor concentrations of CO, PAH, NO, and NO(x) were highly correlated with the corresponding outdoor concentrations. The indoor benzene concentrations showed only moderate correlation with outdoor benzene levels, possibly due to a weak indoor source. Indoor formaldehyde concentrations always exceeded outdoor levels, and the correlation between indoor and outdoor concentrations was not statistically significant, indicating the presence of a strong indoor source.

Air Pollution, Indoor↗

Air pollution and respiratory illness of children in São Paulo, Brazil.

This investigation reports the association between air pollution and paediatric respiratory emergency visits in São Paulo, Brazil, the largest city in South America. Daily records of emergency visits were obtained from the Children's Institute of the University of São Paulo for the period from May 1991 to April 1993. Visits were classified as respiratory and non-respiratory causes. Respiratory visits were further divided into three categories: upper respiratory illness, lower respiratory illness and wheezing. Daily records of SO2, CO, particulate matter (PM10), O3 and NO2 concentrations were obtained from the State Air Pollution Controlling Agency of São Paulo. Associations between respiratory emergency visits and air pollution were assessed by simple comparative statistics, simple correlation analysis and by estimating a variety of regression models. Significant associations between the increase of respiratory emergency visits and air pollution were observed. The most robust associations were observed with PM10, and to a lesser extent with O3. These associations were stable across different model specifications and several controlling variables. A significant increase in the counts of respiratory emergency visits--more than 20%--was observed on the most polluted days, indicating that air pollution is a substantial paediatric health concern in São Paulo.

Adolescent↗

Bioremediation of crude oil polluted soil by the white rot fungus, Pleurotus tuberregium (Fr.) Sing.

Bioremediation has become an attractive alternative to physicochemical methods of remediation of polluted sites. White rot fungi (WRF) are increasingly being investigated and used in bioremediation, because of their ability to degrade an extremely diverse range of very persistent or toxic environmental pollutants. The white rot fungus, Pleurotus tuberregium, was examined for its ability to ameliorate crude oil polluted soil. This was inferred from the ability of the polluted soil to support seed germination and seedling growth in Vigna unguiculata, at 0, 7 and 14 days post treatment. Results obtained from the present study showed that bioremediation of soil contaminated with crude oil was possible, especially when the fungus had been allowed to establish and fully colonize the substrate mixed with the soil. There were significant improvements in % germination, plant height and root elongation values of test plants, when seeds were planted 14 days post soil treatment. At 1 to 5% crude oil pollution, % germination values were comparable with the values in control plants in the 14 days treatment, and significantly higher than values obtained in the day 0 treatment. Also, at the highest level of crude oil pollution (15%), there was about 25% improvement in % germination value over the 0 day treatment. This trend of improvement in values was also observed for plant height, root elongation and biomass accumulation as well as decreased total hydrocarbon content.

Biodegradation, Environmental↗