Smoke Contamination Research Articles

Protecting Children From Toxicants

Protecting Children From Toxicants

Electronic cigarettes and thirdhand tobacco smoke: two emerging health care challenges for the primary care provider.

Primary care providers should be aware of two new developments in nicotine addiction and smoking cessation: 1) the emergence of a novel nicotine delivery system known as the electronic (e-) cigarette; and 2) new reports of residual environmental nicotine and other biopersistent toxicants found in cigarette smoke, recently described as “thirdhand smoke”. The purpose of this article is to provide a clinician-friendly introduction to these two emerging issues so that clinicians are well prepared to counsel smokers about newly recognized health concerns relevant to tobacco use. E-cigarettes are battery powered devices that convert nicotine into a vapor that can be inhaled. The World Health Organization has termed these devices electronic nicotine delivery systems (ENDS). The vapors from ENDS are complex mixtures of chemicals, not pure nicotine. It is unknown whether inhalation of the complex mixture of chemicals found in ENDS vapors is safe. There is no evidence that e-cigarettes are effective treatment for nicotine addiction. ENDS are not approved as smoking cessation devices. Primary care givers should anticipate being questioned by patients about the advisability of using e-cigarettes as a smoking cessation device. The term thirdhand smoke first appeared in the medical literature in 2009 when investigators introduced the term to describe residual tobacco smoke contamination that remains after the cigarette is extinguished. Thirdhand smoke is a hazardous exposure resulting from cigarette smoke residue that accumulates in cars, homes, and other indoor spaces. Tobacco-derived toxicants can react to form potent cancer causing compounds. Exposure to thirdhand smoke can occur through the skin, by breathing, and by ingestion long after smoke has cleared from a room. Counseling patients about the hazards of thirdhand smoke may provide additional motivation to quit smoking.

Assessment of Environmental Tobacco Smoke Contamination in Public Premises: Significance of 2,5-Dimethylfuran as an Effective Marker

Contamination by environmental tobacco smoke (ETS) on premises where smoking is permitted is evaluated. Although all target VOCs evaluated show significant differences between smoking and nonsmoking indoors, the results obtained indicate that 2,5-dimethylfuran is the most appropriate and effective marker of ETS contamination given that this compound is only detected in environments where people have smoked and so the detection of this compound cannot be attributed to other contamination sources such as traffic. Moreover, the air levels of this compound due to coffee aroma are below the detection limits for this methodology. A preliminary study is performed to evaluate whether 2,5-dimethylfuran, a smoking breath biomarker, can be detected in passive smokers working in smoking environments. The compound was continuously detected in the breath of nonsmoking employees after being in direct contact with ETS for just a few hours. The Tedlar gas sampling bags had 5% loss of 2,5-dimethylfuran after 3 h of storage, which we took as the maximum recommended period for air sample storage.

3차 간접흡연의 과학적 증거의 고찰

Tobacco smoking and secondhand smoke exposure are linked to a number of adverse health outcomes. There is a new concept of thirdhand smoke that is residual tobacco smoke contamination remained after the cigarette is extinguished. This paper reviews published studies examining the residual tobacco smoke. Tobacco smoke can be attached to various surfaces and reemitted to air for long period of time. The dynamic process can allow thirdhand smoke exposure to tobacco smoke without direct exposure to secondhand smoke. One critical evidence of the thirdhand smoke exposure was significantly high urinary cotinine level of infant who did not have direct secondhand smoke exposure. Potential exposure to new and more potent chemicals generated from chemical reactions between residual tobacco smoke and ambient air pollutants can get more attention. Considering toxicity and exposure route, children are uniquely susceptible to thirdhand smoke exposure. The review provides strong background information for thirdhand smoke but warrant more researches on this issue.

Physical Scale Modeling of Smoke Contamination in Upper Balconies by a Channeled Balcony Spill Plume in an Atrium

Whether the balcony spill plume will rise unhindered as a free plume or curl inward and interact with the atrium structure is dependent upon a number of factors. Not all the factors are well investigated and wholly understood, resulting in limited guidance for fire engineers. This article systematically investigates the effects of varying balcony breadths, plume widths, and fire sizes on smoke contamination in upper balconies through a series of smoke flow experiments conducted using a one-tenth physical scale model representing a six-story atrium building. The scale model simulated a fire in an adjacent compartment connecting to a fully open atrium. Visual observations and temperature measurements of the smoke flows were carried out. From the results, it was established that the extent of smoke contamination in upper balconies increased with decreasing balcony breadths, increasing plume widths, and decreasing fire sizes. Analysis showed that the aspect ratio of plume width to balcony breadth can be used to determine whether smoke contamination of upper balconies will occur. Where contamination is likely, an empirical correlation was developed to determine the minimum height of contamination above the lowest balcony of smoke contamination.

Indoor concentrations of nicotine in low-income, multi-unit housing: associations with smoking behaviours and housing characteristics

Objective:An analysis of airborne nicotine measurements collected in 49 low-income, multi-unit residences across the Greater Boston Area.Methods:Nicotine concentrations were determined using passive monitors placed in homes over a one-week sampling...

Beliefs About the Health Effects of “Thirdhand” Smoke and Home Smoking Bans

There is no safe level of exposure to tobacco smoke. Thirdhand smoke is residual tobacco smoke contamination that remains after the cigarette is extinguished. Children are uniquely susceptible to thirdhand smoke exposure. The objective of this study was to assess health beliefs of adults regarding thirdhand smoke exposure of children and whether smokers and nonsmokers differ in those beliefs. We hypothesized that beliefs about thirdhand smoke would be associated with household smoking bans. Data were collected by a national random-digit-dial telephone survey from September to November 2005. The sample was weighted by race and gender within Census region on the basis of US Census data. The study questions assessed the level of agreement with statements that breathing air in a room today where people smoked yesterday can harm the health of children. Of 2000 eligible respondents contacted, 1510 (87%) completed surveys, 1478 (97.9%) answered all questions pertinent to this analysis, and 273 (18.9%) were smokers. Overall, 95.4% of nonsmokers versus 84.1% of smokers agreed that secondhand smoke harms the health of children, and 65.2% of nonsmokers versus 43.3% of smokers agreed that thirdhand smoke harms children. Strict rules prohibiting smoking in the home were more prevalent among nonsmokers: 88.4% vs 26.7%. In multivariate logistic regression, after controlling for certain variables, belief that thirdhand smoke harms the health of children remained independently associated with rules prohibiting smoking in the home. Belief that secondhand smoke harms the health of children was not independently associated with rules prohibiting smoking in the home and car. This study demonstrates that beliefs about the health effects of thirdhand smoke are independently associated with home smoking bans. Emphasizing that thirdhand smoke harms the health of children may be an important element in encouraging home smoking bans.

Discrete-element modeling of particulate aerosol flows

A multiple-time step computational approach is presented for efficient discrete-element modeling of aerosol flows containing adhesive solid particles. Adhesive aerosol particulates are found in numerous dust and smoke contamination problems, including smoke particle transport in the lungs, particle clogging of heat exchangers in construction vehicles, industrial nanoparticle transport and filtration systems, and dust fouling of electronic systems and MEMS components. Dust fouling of equipment is of particular concern for potential human occupation on dusty planets, such as Mars. The discrete-element method presented in this paper can be used for prediction of aggregate structure and breakup, for prediction of the effect of aggregate formation on the bulk fluid flow, and for prediction of the effects of small-scale flow features (e.g., due to surface roughness or MEMS patterning) on the aggregate formation. After presentation of the overall computational structure, the forces and torques acting on the particles resulting from fluid motion, particle–particle collision, and adhesion under van der Waals forces are reviewed. The effect of various parameters of normal collision and adhesion of two particles are examined in detail. The method is then used to examine aggregate formation and particle clogging in pipe and channel flow.

Residual tobacco smoke pollution in used cars for sale: Air, dust, and surfaces

Regular tobacco use in the enclosed environment of a car raises concerns about longer-term contamination of a car's microenvironment with residual secondhand smoke pollutants. This study (a) developed and compared methods to measure residual contamination of cars with secondhand smoke, (b) examined whether cars of smokers and nonsmokers were contaminated by secondhand smoke, and (c) how smoking behavior and restrictions affected contamination levels. Surface wipe, dust, and air samples were collected in used cars sold by nonsmokers (n = 20) and smokers (n = 87) and analyzed for nicotine. Sellers were interviewed about smoking behavior and restrictions, and car interiors were inspected for signs of tobacco use. Cars of smokers who smoked in their vehicles showed significantly elevated levels of nicotine (p < .001) in dust, on surfaces, and in the air compared with nonsmoker cars with smoking ban. When smokers imposed car smoking bans, air nicotine levels were significantly lower (p < .01), but dust and surface contamination levels remained at similar levels. Smoking more cigarettes in the car and overall higher smoking rate of the seller were significantly associated with higher secondhand smoke contamination of the car (p < .001). Use of a cutpoint for nicotine levels from surface wipe samples correctly identified 82% of smoker cars without smoking bans, 75% of smoker cars with bans, and 100% of nonsmoker cars. Surface nicotine levels provide a relatively inexpensive and accurate method to identify cars and other indoor environments contaminated with residual secondhand smoke. Disclosure requirements and smoke-free certifications could help protect nonsmoking buyers of used cars.

Flame interactions and smoke containment by downward displacement ventilation

Smoke contamination even from small fires of sensitive components in telephone central offices (TCO) and semiconductor clean rooms has caused disastrous disruptions in services and excessive financial repercussions. Containment and removal of smoke can be achieved by downward displacement ventilation, also used for other purposes in large floor area semiconductor facilities. Downward ventilation reverses the upward flow from the fire and removes the smoke and other combustion products through the floor. Small-scale model experiments under turbulent fire plume conditions investigate the physical parameters such as downward velocity, ceiling clearance, and size of the fire that control the extent of the smoke containment around the fire. The extent of smoke contamination is mapped by measuring the temperatures in several locations on the vertical axis and in the space around the fire. The downward velocities cause oscillation of the fire plume and the flames around the vertical axis. By combining the experimental data with similarity analysis, a characteristic length scale and nondimensional relations are deduced for the extent of the smoke containment and the onset of plume oscillations. These relations allow design of displacement ventilation effective to contain the smoke but not cause fire spread owing to the leaning of the flames. Previously reported discrepancies in the apparent width and behavior of the plume are resolved by examining the experimental data and assessing the suitability of steady state computational fluid dynamics to model the present flow.

Wildfire temperature and land cover modeling using hyperspectral data

Wildfire temperature retrieval commonly uses measured radiance from a middle infrared channel and a thermal infrared channel to separate fire emitted radiance from the background emitted radiance. Emitted radiance at shorter wavelengths, including the shortwave infrared, is measurable for objects above a temperature of 500 K. The spectral shape and radiance of thermal emission within the shortwave infrared can be used to retrieve fire temperature. Airborne Visible Infrared Imaging Spectrometer (AVIRIS) data were used to estimate fire properties and background properties for the 2003 Simi Fire in Southern California, USA. A spectral library of emitted radiance endmembers corresponding to a temperature range of 500–1500 K was created using the MODTRAN radiative transfer model. A second spectral library of reflected solar radiance endmembers, corresponding to four vegetation types and two non-vegetated surfaces, was created using image spectra selected by minimum endmember average root mean square error (RMSE). The best fit combination of an emitted radiance endmember and a reflected solar radiance endmember was found for each spectrum in the AVIRIS scene. Spectra were subset to reduce the effects of variable column water vapor and smoke contamination over the fire. The best fit models were used to produce maps of fire temperature, fire fractional area, background land cover, land cover fraction, and RMSE. The highest fire temperatures were found along the fire front, and lower fire temperatures were found behind the fire front. Saturation of shortwave infrared channels limited modeling of the highest fire temperatures. Spectral similarity of land cover endmembers and smoke impacted the accuracy of modeled land cover. Sensitivity analysis of modeled fire temperatures revealed that the range of temperatures modeled within 5% of minimum RMSE was smallest between 750 and 950 K. Hyperspectral modeling of wildfire temperature and fuels has potential application for fire monitoring and modeling.

A Comparison of Driving Forces for Smoke Movement in Buildings

It has been suggested that automatic shutdown of mechanical ventilation systems upon smoke detection may be superfluous and unnecessary because other driving forces will continue to transport smoke throughout buildings after the ventilation systems have been shut down. To evaluate this hypothesis, an analysis is presented that considers the relative smoke concentrations throughout a building arising from the driving forces of stack effect, wind effect, and buoyancy of combustion gases as well as those arising from mechanical ventilation. This analysis considers a representative 10-story building, but the approach presented can be extended to buildings of different heights and areas. The results of this study indicate that the shutdown of mechanical ventilation may not prevent the smoke contamination of nonfire floors, but it may still be preferable to leaving ventilation systems running unless the systems are specifically designed for smoke management.

Effects of Smoke Emissions from a Charcoal Kiln on the Functioning of Forest Soil Systems: A Microcosm Study

Long-term charcoal production in small private charcoal kilns (CK) in Eastern Bieszczady Mts. (SE Poland) can cause local smoke contamination of the ambient forest environment. Responses of model soil systems, contaminated or not contaminated by CK smoke, to contrasting combinations of hydrothermic regimes were compared in laboratory microcosms (respiration of soil community, decomposition rate of soil organic matter and cotton stripes, herb seeds germination were studied). The majority of the obtained data show a markedly higher level of soil biological activity in the CK versus the control series. In some cases CK and control soil systems show different patterns of reactions to the tested combinations of microclimate regime. These phenomena should at least partly be attributed to the effects of CK pollution.

Purge and trap/gas chromatography/mass spectrometry method for determining smoke contamination of foods and packaging materials

Food and packaging materials from three separate fires were analyzed for volatiles by purge and trap/gas chromatography/mass spectrometry (PT/GC/MS) and compared to unexposed control samples. Concentrations of naphthalene and small alkyl-substituted (methyl, ethyl, dimethyl) naphthalene residues were consistently higher in the smoke odor containing foods than in the controls. Naphthalene and methylnaphthalene residues were used as indicators of smoke exposure in food and packaging materials. By using this method to analyze foods that had been exposed to smoke yet contained no organoleptically detectable smoke residues, it was shown that this PT/GC/MS naphthalene method is a more sensitive indicator of smoke exposure than is organoleptic evaluation.

Cleaning and reliability of smoke-contaminated electronics

This work deals with problems that arise when modern surface-mounted electronics are to be reconditioned after smoke contamination. In a fire, hydrogen chloride, which is formed when polyvinylchloride is present, is deposited on various materials. Electronic equipment is especially sensitive since malfunction may occur after a longer or shorter time of operation due to the chloride contamination. Earlier work has shown that through-hole electronics can be reconditioned, with good results, after deposition of up to 100 µg chloride/cm2 in the surrounding area. The lower limit when cleaning is needed is often specified to 10 µg chloride/cm2. In this work, therefore, surface-mounted electronics have been exposed to smoke containing hydrogen chloride, which has contaminated the test boards with 45 to 75 µg chloride/cm2. Three different methods for cleaning smoke-contaminated electronics were investigated: manual, automatic spray, and ultrasonic. Each method was able to clean to a contamination level lower than 1.5 µg sodium chloride equivalents/cm2. The automatic spray method could not remove all contaminants beneath the components. All three methods were capable of improving the surface insulation resistance to a satisfactory level. Conformal coating can, to a large extent, protect the electronics against corrosive smoke. However, decontamination of boards conformally coated with acrylic coatings may be complicated since smoke products are partly absorbed into the conformal coating. The large difference between chloride contamination in a fire and during the manufacture of electronic equipment is the nature of deposition. Experiments have shown that the hydrogen chloride reacts with lead in the solder to form lead chloride. During manufacture, chloride salts are deposited all over the test board. Migration between conductors of different potential has not occurred. This is due to the fact that chloride is localized on the conductors as lead chloride. Galvanic corrosion, on the other hand, has occurred between metals within one conductor.

Experimental Fire Tower Studies On Mechanical Pressurization On Control Smoke Movement Caused By Fire Pressures

In designing a mechanical smoke control system to protect escape routes, it is necessary to have information on the adverse pressure differences caused by the various mechanisms and on the level of mechanical pressurization needed t o overcome them. This paper deals with pressure differences caused by both the buoyancy force and thermal expansion due to fire. The tests were conducted in the ten-storey experimental fire tower in conjunction with a project on smoke control technology for a fire safe elevator. The calculated values of adverse pressure differences across the elevator shaft walls caused by the buoyancy force agreed well with the measured values, for fire temperatures from 450 to 850°C. Also, the minimum amounts of mechanical pressurization required for neutralization were equal to the adverse pressures caused by the buoyancy force. Those caused by thermal expansion due to the rapid temperature rise were determined with the outside wall vents closed and with them opened. The test results verified that adverse pressures caused by fire can be controlled by mechanical pressurization to prevent smoke contamination of protected spaces. The mechanical pressurization system should be operated as soon as possible as the purging time f o r a contaminated elevator shaft or lobby can be long.

Time-course of cigarette smoke contamination of clinical hydrogen breath-analysis tests.

The time-course of the contamination of exogenous hydrogen from cigarette smoke on postprandial breath hydrogen concentration was evaluated in 10 subjects, six regular smokers and four occasional smokers. Breath hydrogen values were determined by gas chromatography 10 min, 5 min, and immediately prior to smoking a filter cigarette; during smoking from a sample of exhaled air containing smoke; and 5, 10, and 15 min after extinguishing the cigarette. A three- to 137-fold increase above basal hydrogen concentrations was produced by exhaled cigarette smoke, but most subjects had re-equilibrated to baseline values within 10 to 15 min after the cigarette. If subjects undergoing clinical hydrogen breath tests cannot refrain from smoking during the duration of the test, one should allow an interval of at least 15 min from the end of smoking to the collection of a breath sample.

Modeling of NBS mattress tests with the harvard mark V fire simulation

AbstractNBS burned eleven mattresses made up with bedding in two different rooms, typical of a residential bedroom and a nursing home patient room, respectively. Seven of the mattresses flamed and burned vigorously, the other four were of a construction or so heavily flame‐inhibited that they only smoldered. The burning behavior of the seven that flamed was modeled with the Harvard Mark V fire simulation. The experimental burn behavior for tests conducted in one room was well reproduced using only total weight of combustible, surface area and heat of combustion. Smoke production values were found to have little effect on the predicted behavior except for the smoke production itself. Fires in a second room, whose ventilation was intentionally restricted by the configuration of the adjoining space, could not be as well reproduced by the present, single‐room fire model. During this study several changes were made to the simulation. The most significant change was the inclusion of mixing of the hot exiting fire gases with the cold incoming air. As a part of this, the inter‐layer radiation exchange was reformulated to include the effect of smoke contamination of the lower layer. The reformulation of the radiation model has a marked effect on the predicted upper layer gas temperatures, generally improving the quality of the simulation.

Smoke concentration in the greater Cairo atmosphere

A study of smoke content of the atmosphere over the Greater Cairo area was conducted during the 12 months from June 1977 to May 1978. Smoke samples were taken continuously over two-hour periods at two sites, one in Shubra El-Kheima industrial sector on the northern boundary of the study area and the other in a purely residential district about 15 km south-south-west of the first site. A comparison was made between the averaged concentrations at both sites. It was found that the industrial area was considerably higher in smoke contamination and that industrial activity is the principal source of smoke in the Cairo atmosphere. Daily and yearly cycles of smoke concentration were also studied and discussed in terms of man-made source activities and meteorological conditions. Concentrations were found to be much higher in the cold months. The daily cycle rhythm was the same at the two sites, having two well developed maxima in the morning and late evening and a pronounced minimum in the mid-afternoon. Daily maxima were almost of the same order of magnitude in each site. The morning maximum seemed to be formed by fumigation just after sunrise in the industrial sector and appeared two hours later in the downwind residential district. No significant difference was found between smoke concentrations during weekdays and weekends.

METHOD FOR THE MEASUREMENT OF PHENOLS ASSOCIATED WITH THE SMOKY/HAMMY FLAVOR DEFECT OF COCOA BEANS AND CHOCOLATE LIQUOR

ABSTRACTA procedure for extraction of flavor components from cocoa beans and chocolate liquor with acetonitrile is described. After removal of interfering substances, phenolic compounds in the extract are reacted with N,2,6‐trichloro‐p‐benzoquinoneimine to form colored indophenols. A high correlation (0.89) was found between the concentration of phenols and the results of taste panel evaluation for the smoky/hammy defect caused by smoke contamination. The procedure is applicable to quality control evaluation of cocoa beans and chocolate liquor received from producing countries.