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Residential environmental risks for reproductive age women in developing countries.

Published research suggests there is an association between maternal inhalation of common ambient air pollutants and adverse birth outcomes, including an increased risk for preterm delivery, intrauterine growth retardation, small head circumference, low birth weight, and increased rate of malformations. The air pollutants produced by indoor combustion of biomass fuels, used by 50% of households worldwide, have been linked to acute lower respiratory infections, the single most important cause of mortality in children under the age of 5. This report describes a hypothesis-generating study in West Wollega, Ethiopia, conducted to assess airborne particulate matter concentrations in homes that combust biomass fuels (biomass homes). Respirable suspended particulate matter was measured in biomass homes and nonbiomass homes using NIOSH method 0600. Measured airborne particulate concentrations in biomass homes were up to 130 times higher than air quality standards. These findings, in part, confirm that exposure to indoor air pollutants are a major source of concern for mother/child health. Midwives are encouraged to raise awareness, contribute to research efforts, and assist in interventions.

Adult↗

Review of air pollution and health impacts in Malaysia.

In the early days of abundant resources and minimal development pressures, little attention was paid to growing environmental concerns in Malaysia. The haze episodes in Southeast Asia in 1983, 1984, 1991, 1994, and 1997 imposed threats to the environmental management of Malaysia and increased awareness of the environment. As a consequence, the government established Malaysian Air Quality Guidelines, the Air Pollution Index, and the Haze Action Plan to improve air quality. Air quality monitoring is part of the initial strategy in the pollution prevention program in Malaysia. Review of air pollution in Malaysia is based on the reports of the air quality monitoring in several large cities in Malaysia, which cover air pollutants such as Carbon monoxide (CO), Sulphur Dioxide (SO2), Nitrogen Dioxide (NO2), Ozone (O3), and Suspended Particulate Matter (SPM). The results of the monitoring indicate that Suspended Particulate Matter (SPM) and Nitrogen Dioxide (NO2) are the predominant pollutants. Other pollutants such as CO, O(x), SO2, and Pb are also observed in several big cities in Malaysia. The air pollution comes mainly from land transportation, industrial emissions, and open burning sources. Among them, land transportation contributes the most to air pollution. This paper reviews the results of the ambient air quality monitoring and studies related to air pollution and health impacts.

Air Pollutants↗

Indoor air quality in ice skating rinks in Hong Kong.

Indoor air quality in ice skating rinks has become a public concern due to the use of propane- or gasoline-powered ice resurfacers and edgers. In this study, the indoor air quality in three ice rinks with different volumes and resurfacer power sources (propane and gasoline) was monitored during usual operating hours. The measurements included continuous recording of carbon monoxide (CO), carbon dioxide (CO(2)), total volatile organic compounds (TVOC), particulate matter with a diameter less than 2.5 microm (PM(2.5)), particulate matter with diameter less than 10 microm (PM(10)), nitric oxide (NO), nitrogen dioxide (NO(2)), nitrogen oxide (NO(x)), and sulfur dioxide (SO(2)). The average CO, CO(2), and TVOC concentrations ranged from 3190 to 6749 microg/m(3), 851 to 1329 ppm, and 550 to 765 microg/m(3), respectively. The average NO and NO(2) concentrations ranged from 69 to 1006 microg/m(3) and 58 to 242 microg/m(3), respectively. The highest CO and TVOC levels were observed in the ice rink which a gasoline-fueled resurfacer was used. The highest NO and NO(2) levels were recorded in the ice rink with propane-fueled ice resurfacers. The air quality parameters of PM(2.5), PM(10), and SO(2) were fully acceptable in these ice rinks according to HKIAQO standards. Overall, ice resurfacers with combustion engines cause indoor air pollution in ice rinks in Hong Kong. This conclusion is similar to those of previous studies in Europe and North America.

Air Pollution, Indoor↗

Exposure efficiency: an idea whose time has come?

Exposure efficiency, the fraction of material released from a source that is eventually inhaled or ingested, is arguably the simplest of all possible descriptions of the link between pollutant emissions and population exposures. This paper, prepared in late 1999 for the SGOMSEC Workshop, notes that several groups of researchers independently developed the concept of exposure efficiency in the late 1980s and early 1990s but argues that the potential importance of exposure efficiency in risk analysis and life cycle assessment has only recently been appreciated. The paper reviews the history of the concept; discusses and summarizes previous estimates of exposure efficiency for particulate matter and other air pollutants; presents new values for fine particulate matter emitted from power plants and mobile sources in the United States; and illustrates how preliminary estimates of exposure efficiency might be developed. The authors assert that in order for the concept of exposure efficiency to achieve its full potential exposure efficiency estimates for a wide variety of pollutants and sources must be developed and that both the results and methods must be made widely available and accessible to the community of risk assessors and life cycle analysts.

Air Pollutants↗

Analysis of temporal and spatial dichotomous PM air samples in the El Paso-Cd. Juarez air quality basin.

This paper presents and discusses the results obtained from the gravimetric and chemical analyses of the 24-hr average dichotomous samples collected from five sites in the El Paso-Cd. Juarez air quality basin between August 1999 and March 2000. Gravimetric analysis was performed to determine the temporal and spatial variations of PM2.5 (particulate matter less than 2.5 microm in diameter) and PM25-10 (particulate matter less than 10 pm but greater than 2.5 microm in diameter) mass concentrations. The results indicate that approximately 25% of the PM10 (i.e., PM25 + PM25-10) concentration is composed of PM2.5. Concurrent measurements of hourly PM concentrations and wind speed showed strong diurnal patterns of the regional PM pollution. Results of X-ray fluorescence (XRF) elemental analyses were compared to similar but limited studies performed by the Texas Natural Resource Conservation Commission (TNRCC) in 1990 and 1997. Major elements from geologic sources-Al, Si, Ca, Na, K, Fe, and Ti-accounted for 35% of the total mass concentrations in the PM2.5-10 fraction, indicating that geologic sources in the area are the dominant PM sources. Levels of toxic trace elements, mainly considered as products of anthropogenic activities, have decreased significantly from those observed in 1990 and 1997.

Air Pollutants↗

Associations between outdoor air pollutants and hospitalization for respiratory diseases.

The concentration of particulate matter in outdoor air, as indicated by daily measures of particulate matter 10 microm in diameter (PM10) in many cities, has been found to be associated with the daily number of deaths and hospital admissions in these cities. To understand this association better, we studied the daily number of hospital admissions for respiratory diseases and the concentrations of eight pollutants in ambient air, during a period of 38 months, in an area with cold winters and air pollution that comes mainly from motor vehicles. We estimated the changes in risk of hospitalization by interquartile increases in pollutant concentrations by Poisson regression analyses. Controlling for periodic trends and weather, the relative risk of hospitalization associated with an interquartile increase of PM10 was 1.038 [95% confidence interval (CI) = 0.991-1.087]. In contrast, the relative risk associated with benzene was 1.105 (95% CI = 1.047-1.166). In a two-pollutant model, the relative risk estimates were 1.014 (95% CI = 0.966-1.063) for PM10 and 1.090 (95% CI = 1.031-1.153) for benzene. We evaluated other two- and three-pollutant models and concluded that pollutants other than PM10 are more strongly associated with hospital admissions for respiratory diseases.

Air Pollutants↗

Corrosion of amalgams.

The release of copper, mercury, silver, tin or zinc from conventional, dispersed phase and spherical high copper content amalgams immersed in artificial saliva solutions for periods up to 30 d has been measured using nuclear tracer techniques. During initial corrosion, i.e. within a few hours substantial amounts of mercury were found to be present in particulate matter in the three types of amalgams. The release of particulate matter was pronounced for the dispersed phase type of amalgam. After about 30 electrochemical corrosion was found to be the predominant process for release of various corrosion products. Zinc was demonstrated to be the major corrosion product released to the artificial saliva solutions from conventional as well as dispersed phase amalgams. Due to low radioactivity levels silver and tin could not be quantitatively assayed. However, the upper limits of silver and tin in the artificial saliva solutions referring to exposure periods up to 30 d were estimated to 0.1 microgram and 25 microgram respectively. The chemical state of the various corrosion products has been evaluated. The deposition of CuCl2 X 3 Cu(OH)2 on the surfaces of copper rich amalgams was observed according to X-ray diffraction analysis.

Chemical Phenomena↗

Ambient air quality and occurrence of multiple sclerosis relapse.

Infectious viruses and bacteria can trigger multiple sclerosis (MS) exacerbations. Seasonally changing concentrations of ambient air pollutants are known to predispose to transmissible infections, to induce systemic immune responses and to enhance existing peripheral inflammation. Ambient air quality and monthly MS relapse occurrence in south-western Finland were compared by multivariate logistic regression. The odds ratio of the risk of a relapse onset was over fourfold (4.143, p < 0.001) when the concentration of inhalable particulate matter (PM(10)) was at the highest quartile. Inhalable airborne particulate matter concentrations were connected to relapse occurrence. Poor air quality may enhance the seasonal changes in MS relapse occurrence by an increased susceptibility to transmissible infections.

Air Pollution↗

Use of respiratory protection among responders at the World Trade Center site--New York City, September 2001.

The terrorist attacks on the World Trade Center (WTC) on September 11,2001, created an occupational health and safety challenge for New York City (NYC) firefighters and rescue workers responding to the disaster. Immediate respiratory hazards included explosions, fire, falling debris, and dust clouds containing particulate matter comprised of pulverized building materials. Ongoing risks included lingering particulate matter in the air and intermittent combustion products from initial and persistent fires beneath the rubble pile. Because the nature and extent of exposures in disaster situations are complex and difficult to characterize, the use of adequate personal protective equipment (PPE), including respiratory protection, is essential in protecting the health of firefighters and other rescue workers. During the weeks after September 11, the NYC Fire Department's Bureau of Health Services (FDNY-BHS) and CDC's National Institute for Occupational Safety and Health (NIOSH) organized a collaborative study to evaluate occupational hazards and exposures for these workers, including their use of respiratory protection. This report summarizes the results of that study, which indicate that the majority of firefighters did not use adequate respiratory protection during the first week of the rescue/recovery operation.

Aircraft↗

Preliminary results of exposure measurements and health effects of the Vaal Triangle Air Pollution Health Study.

The aim of the Vaal Triangle Air Pollution Health Study is to assess the adequacy of South Africa's air pollution control programme to protect human health. It is a longitudinal study of children aged 8-12 years which will evaluate exposure and effects of outdoor and indoor air pollution levels on the health of more than 10,000 white and black children living in Vanderbijlpark, Sasolburg, Vereeniging, Meyerton, Randvaal, and the Sebokeng/Sharpeville areas (Lekoa), Transvaal, RSA. Extensive data on outdoor and indoor levels of air pollution as well as personal exposures to total suspended particulate matter were collected. Preliminary results indicate that the levels of particulate matter exceed the USA health standards. A health questionnaire administered to 10,187 white children indicated that during the past year 65.9% had suffered from upper respiratory tract illnesses (URI) such as sinusitis, rhinitis and hay fever and 28.9% from lower respiratory tract illnesses (LRI) such as bronchitis, chronic cough and chronic chest illnesses. Parents who perceived that the air pollution in the region is serious had a higher reporting rate of URI/LRI for their children than parents who considered the air pollution not to be serious (77.4% v. 56.8% respectively for URI and 24.1% v. 16.3% respectively for LRI). The effect of this recall bias will be evaluated in later analyses. A statistically significant higher prevalence of LRI was reported in children exposed to parental smoking (25.7% for households where both parents smoked v. 20.8% in households without parental smoking) (odds ratio (OR) 1.32 (1.2-1.5)).(ABSTRACT TRUNCATED AT 250 WORDS)

Air Pollution↗

Spatial and temporal variations of the inherent and apparent optical properties in a shallow coastal lake.

Apparent and inherent optical properties in the coastal lagoon of Fogliano were measured in three seasonal surveys in 2002. Irradiance data from in situ measurements of ultraviolet and visible wavebands permitted to estimate the related attenuation coefficients. Laboratory extinction measurements on filtered (0.22 microm) and unfiltered water samples were also performed. The integrated approach between in situ and laboratory measurements allowed the determination of the role of the suspended and dissolved matter in the attenuation and extinction of ultraviolet and visible radiation within the water column. As noted, the impact of the suspended and dissolved matter on the lake optical quality was influenced by wind resuspension of particulate matter: the relative role of dissolved matter in the absorption of UV and visible radiation was prevailing at low wind velocity conditions (less than 2.2 m s(-1)), while at high wind velocities (3.9 m s(-1)), particulate matter resuspension strongly influenced the attenuation and the extinction measurements. The extinction in the analyzed wavelengths of filtered and unfiltered water samples and the in situ irradiance measurements allowed us to define new optical parameters and important correlations with limnological and classical optical measurements. By sampling at high spatial resolution (18 stations in 4 km2), it was possible to evidence a spatial gradient of the optical and limnological properties, these distributions showed a consistent pattern in all three surveys, and were important for the characterization of the chromophoric dissolved organic matter that was estimated with the spectral slope of the extinction curve spectra. A relatively higher spectral slope was found in the southern basin with respect to the northern, where the maximum values of the attenuation coefficients and limnological parameters were found. These results suggest different sources of dissolved organic matter and/or a different level of photobleaching.

Fresh Water↗

Decreased number of sperms and Sertoli cells in mature rats exposed to diesel exhaust as fetuses.

This study was conducted to follow up the effects of fetal exposure to diesel exhaust on testicular cell numbers and daily sperm production in adulthood. Thirty-six pregnant rats were divided into five groups: groups exposed to total diesel-engine exhaust containing 1.71 mg/m3 particulate matter and 0.80 ppm nitrogen dioxide (high dose) or 0.17 mg/m3 particulate matter and 0.10 ppm nitrogen dioxide (low dose); groups exposed to filtered exhaust without particles containing 0.80 (high dose) or 0.10 (low dose) ppm nitrogen dioxide; and a group exposed to clean air. Exhaust exposure was performed from gestational day 7 to delivery. The numbers of daily produced sperm, spermatids and Sertoli cells in the diesel-exhaust-exposed groups were significantly lower than those in the control group on day 96 after birth. The ratio of spermatids/Sertoli cells and the follicle-stimulating hormone levels in the exposed groups were significantly higher. The present study provides evidence for the first time that mature rats exposed to diesel exhaust during fetus show a decrease in the daily production of sperm due to an insufficient number of Sertoli cells. As both the exhaust-exposed groups showed almost the same reactions toward the inhalation, the gaseous phase must have included the responsible toxicants.

Animals↗

Assimilation of glucose carbon in subcellular rat brain particles in vivo and the problems of axoplasmic flow.

1. Rats were injected with [U-(14)C]glucose and the content of (14)C in proteins and lipids of the cerebral P(1) (;nuclear'), P(2) (;mitochondrial'), P(3) (;microsomal') and high-speed supernatant fractions was measured 7, 22 and 93hr. after injection of labelled glucose. 2. The crude brain mitochondrial fractions (P(2)) were subfractionated on continuous sucrose gradients (0.32-1.8m-sucrose) and the (14)C content of the proteins and lipids of about 20 subfractions was measured. 3. About 40-50% of the (14)C assimilated by brain proteins was found in the P(2) (;mitochondrial') fraction. About 68-70% of the (14)C assimilated by brain lipids was also recovered from the lipids of the P(2) fraction. 4. Between 22 and 93hr. after injection of [U-(14)C]glucose both the amount of (14)C in the protein of the P(2) (;mitochondrial') fraction and the specific activity of this protein increased. The specific activity of the protein of all other particulate fractions (P(1), P(2) and P(3)) and subfractions (obtained from sucrose-density-gradient subfractionation of fraction P(2)) when related to the specific activity of the high-speed supernatant protein also increased during 93hr. after injection of [U-(14)C]glucose. The amount of (14)C in the protein of the high-speed supernatant and the specific activity of this protein decreased during the same period. 5. The distribution of (14)C in the lipids of all subcellular particulate fractions remained unchanged during the period 22-93hr. after injection of [U-(14)C]glucose. 6. It was concluded that a diffusion occurs of some supernatant proteins into subcellular particulate matter of the cerebrum and no significant preference for any subcellular particulate matter was observed. The lipids occur in the cerebrum mainly in a non-diffusible state, which is consistent with the view that they form almost entirely a part of the structure of the cerebrum. 7. The data obtained do not lend further support to the concept of axoplasmic flow within the cerebrum or the concept of a one-directional flow of mitochondria or other subcellular particles within the cerebrum.

Journal Article↗

Respirable dust content of subway air.

During the non-heating months of June, July and August of 1974, the total and respirable dust content at an underground station of the Newark City Subway System was determined. Higher particulate levels than obtained for ambient Newark air were observed. Additionally, Federal Ambient Primary Air Quality Standards for suspended particulate matter was exceeded in two instances. Qualitative elemental analysis of the particulate matter collected is also reported.

Air Pollutants↗

Determination of aliphatic and polycyclic aromatic hydrocarbons in atmospheric particulate samples of A Coruña City (Spain).

The hydrocarbon composition of atmospheric particulate matter from A Coruña city (Northwest Spain) has been studied. TSP (total suspended particulate) and PM10 (particulate matter with aerodynamic diameter < 10 microm) samples were taken over 7 and 4 months at two stations located in residential and industrial sectors of A Coruña city, respectively. The levels of hydrocarbons found in atmospheric particulate samples of A Coruña city are higher than the ones found in other cities over the world. Ratios between the analysed compounds and their sources were established. Both anthropogenic and biogenic origins were found.

Air Pollution↗

Winter urban air particles from Rome (Italy): effects on the monocytic-macrophagic RAW 264.7 cell line.

Epidemiological data show an association between exposure to elevated levels of particulate matter (PM), in particular the fine fraction (<2.5 microm in diameter), and an increase in cardiovascular mortality and respiratory symptoms. The aim of this study was to compare the in vitro toxicity of coarse and fine particulate matter collected with a cascade impactor during winter in an urban area of Rome in relation to their physicochemical characterization (size distribution and chemical composition) as assessed by analytical electron microscopy (SEM/EDX). The X-ray microanalysis data of single particles of coarse and fine matter were analyzed by hierarchical cluster analysis to determine the principal component of the two granulometric fractions. The main chemical difference between the two fractions was the greater abundance of carbonaceous particles in the fine fraction. We compared the ability of coarse and fine fractions, carbon black (CB), and residual oil fly ash (ROFA) to induce arachidonic acid release and tumor necrosis factor-alpha (TNF-alpha) production in the monocytic-macrophagic RAW 264.7 cell line at concentrations of 30 and 120 microg/mL. Our results showed that CB and ROFA were consistently less effective than both fractions of urban particles at inducing an inflammatory reaction in RAW 264.7 cells. Both PM fractions dose-dependently increased TNF-alpha production in RAW 264.7 cells after 5 and 24h of incubation, and only the TNF-alpha production induced by coarse particles at 30 microg/mL decreased significantly (P<0.01) after 24h of treatment. In our in vitro model the winter fine fraction was more reactive than the winter coarse fraction, in contrast to a previously examined summer sample. In the summer sample, coarse particles produced higher levels of inflammatory mediators than fine particles and the CB was consistently less effective than the urban particles. The different behaviors between summer and winter urban fractions may be due to their different physicochemical characteristics; in fact, the comparison of the two samples' characterization by SEM/EDX and X-ray photoelectron spectroscopy (XPS) analysis showed that in winter the carbonaceous particles are more abundant than in summer and that winter particles carry a greater quantity of organic compounds. We suggest that the higher concentration of organic compounds on fine carbonaceous particles may partially explain the higher activation of RAW 264.7 cells by fine particles.

Air Pollutants↗

Mercury distribution in Douro estuary (Portugal).

Determinations of dissolved reactive and total dissolved mercury, particulate and sedimentary mercury, dissolved organic carbon (DOC), particulate organic carbon (POC) and suspended particulate matter (SPM) have been made in the estuary of river Douro, in northern Portugal. The estuary was stratified by salinity along most of its length, it had low concentrations of SPM, typically <20 mg dm(-3), and concentrations of DOC in the range <1.0-1.8 mg dm(-3). The surface waters had a maximum dissolved concentration of reactive mercury of about 10 ng dm(-3), whereas for the more saline bottom waters it was about 65 ng dm(-3). The surface waters had maximum concentrations of total suspended particulate mercury of approximately 7 microg g(-1) and the bottom waters were always <1 microg g(-1). Concentrations of mercury in sediments was low and in the range from 0.06 to 0.18 microg g(-1). The transport of mercury in surface waters was mainly associated with organic-rich particulate matter, while in bottom waters the dissolved phase transport of mercury is more important. Lower particulate organic matter, formation of chlorocomplexes in more saline waters and eventually the presence of colloids appear to explain the difference of mercury partitioning in Douro estuarine waters.

Carbon↗

Genetic susceptibility to nickel-induced acute lung injury.

Human exposure to insoluble and soluble nickel compounds is extensive. Besides wide usage in many industries, nickel compounds are contained in cigarette smoke and, in low levels, in ambient particulate matter. Soluble nickel particulate, especially nickel sulfate (NiSO(4)), has been associated with acute lung injury. To begin identifying genes controlling susceptibility to NiSO(4), mean survival times (MSTs) of eight inbred mouse strains were determined after aerosol exposure. Whereas A/J (A) mice were sensitive, C57BL/6J (B6) mice survived nearly twice as long (resistant). Their offspring were similarly resistant, demonstrating heritability as a dominant trait. Quantitative trait locus (QTL) analysis of backcross mice generated from these strains identified a region on chromosome 6 significantly linked to survival time. Regions on chromosomes 1 and 12 were suggestive of linkage and regions on chromosomes 8, 9, and 16 contributed to the response. Haplotype analysis demonstrated that QTLs on chromosomes 6, 9, 12, and 16 could explain the MST difference between the parental strains. To complement QTL analysis results, cDNA microarray analysis was assessed following NiSO(4) exposure of A and B6 mice. Significant expression changes were identified in one or both strains for >100 known genes. Closer evaluation of these changes revealed a temporal pattern of increased cell proliferation, extracellular matrix repair, hypoxia, and oxidative stress, followed by diminished surfactant proteins. Certain expressed sequence tags clustered with known genes, suggesting possible co-regulation and novel roles in pulmonary injury. Together, results from QTL and microarray analyses of nickel-induced acute lung injury survival allowed us to generate a short list of candidate genes.

Adaptation, Physiological↗