Factors promoting the exposure to bioaerosols among crop workers

Agricultural workers are among the professional groups most at risk of developing acute or chronic respiratory problems. Despite this fact, the etiology of these occupational diseases is poorly known, even in important sectors of agriculture such as the crops sector. A chronic exposure to multiple microorganisms, such as different bacterial and fungal species, has been proposed to be the cause of these multiple respiratory pathologies. Nevertheless, these microbial communities are still partially known. The aim of this study is to characterize all fungal species inhaled by the crops workers during different grain related activities and identify the abiotic and biotic factors that reduce the growth of the toxigenic, irritative or allergenic microbial species. Here, we are presenting the factors promoting the exposure to bioaerosols during different wheat related activities: harvesting, grain unload, baling straw, the cleaning of harvesters and silos. Total dust has been quantified following NIOSH 0500 method. Reactive endotoxin activity has been determined with Limulus Amebocyte Lysate Assay. All molds have been identified by the pyrosequencing of ITS2 amplicons generated from bioaerosol.

Effects of bioaerosol exposure on work-related symptoms among Swiss sawmill workers

Objective Exposure to bioaerosols in the occupational environment of sawmills could be associated with a wide range of health effects, in particular respiratory impairment, allergy and organic dust toxic syndrome. The objective of the study was to assess the frequency of medical respiratory and general symptoms and their relation to bioaerosol exposure. Method Twelve sawmills in the French part of Switzerland were investigated and the relationship between levels of bioaerosols (wood dust, airborne bacteria, airborne fungi and endotoxins), medical symptoms and impaired lung function was explored. A health questionnaire was distributed to 111 sawmill workers. Results The concentration of airborne fungi exceeded the limit recommended by the Swiss National Insurance (SUVA) in the twelve sawmills. This elevated fungi level significantly influenced the occurrence of bronchial syndrome (defined by cough and expectorations). No other health effects (irritations or respiratory effects) could be associated to the measured exposures. We observed that junior workers showed significantly more irritation syndrome (defined by itching/running nose, snoring and itching/red eyes) than senior workers. Lung function tests were not influenced by bioaerosol levels nor dust exposure levels. Conclusion Results suggest that occupational exposure to wood dust in a Swiss sawmill does not promote a clinically relevant decline in lung function. However, the occurrence of bronchial syndrome is strongly influenced by airborne fungi levels. [Authors]

Propagation dans l'environnement des microorganismes et autres particules organiques issus des élevages intensifs et conséquences pour la santé des riverains

Les élevages d'animaux de rente hébergent de plus en plus de bêtes. Cette situation génère une accumulation de poussière organique, constituée de particules inertes et de microorganismes, issus de la nourriture, de la litière, des matières fécales, des pellicules de la peau, des poils, etc. L'activité des animaux et l'activité professionnelle favorisent une remise en suspension de cette poussière, qui peut se propager à l'extérieur. Ces émissions de particules organiques dans l'environnement soulèvent des inquiétudes pour la santé des riverains. Ces craintes sont légitimes, puisque les problèmes respiratoires, allergiques ou toxiques sont bien connus chez les travailleurs agricoles exposés à de fortes doses de poussières organiques. Un autre risque sanitaire lié aux élevages intensifs d'animaux est la dissémination de bactéries résistantes aux antibiotiques dans l'environnement avec, pour éventuelle conséquence, une transmission de ces souches aux personnes résidant à proximité. Cette problématique est bien connue dans les élevages de porcs fréquemment colonisés par des SARM (Staphylococcus aureus résistant à la méticilline), qui sont transmis aux éleveurs. Les deux études analysées ci-dessous ont investigué cette problématique de dissémination des particules organiques dans l'environnement et les conséquences sur la santé des riverains. La première a étudié le lien entre le fait de résider à proximité de fermes d'élevage d'animaux et la prévalence de maladies respiratoires. La deuxième a étudié le risque de colonisation nasale par des SARM dans une population de vétérans vivant à proximité d'élevages intensifs de porcs.

Pieces of Iowa’s Past, April 10, 2013

Pieces of Iowa’s Past, published by the Iowa State Capitol Tour Guides weekly during the legislative session, features historical facts about Iowa, the Capitol, and the early workings of state government. All historical publications are reproduced here with the actual spelling, punctuation, and grammar retained THIS WEEK:Controlling Noise and Dust During the 1956 Replacement of the Old Floor Tile on First Floor of Capitol BACKGROUND:This article was copied from the Capitol Building Newspaper Clippings Scrapbook. The scrapbook contains clippings from 1906 to the 1970s and was compiled by the State Library of Iowa—Law Library.

Rockfall induced seismic signals: case study in Montserrat, Catalonia

After a rockfall event, a usual post event survey includes qualitative volume estimation, trajectory mapping and determination of departing zones. However, quantitative measurements are not usually made. Additional relevant quantitative information could be useful in determining the spatial occurrence of rockfall events and help us in quantifying their size. Seismic measurements could be suitable for detection purposes since they are non invasive methods and are relatively inexpensive. Moreover, seismic techniques could provide important information on rockfall size and location of impacts. On 14 February 2007 the Avalanche Group of the University of Barcelona obtained the seismic data generated by an artificially triggered rockfall event at the Montserrat massif (near Barcelona, Spain) carried out in order to purge a slope. Two 3 component seismic stations were deployed in the area about 200 m from the explosion point that triggered the rockfall. Seismic signals and video images were simultaneously obtained. The initial volume of the rockfall was estimated to be 75 m3 by laser scanner data analysis. After the explosion, dozens of boulders ranging from 10¿4 to 5 m3 in volume impacted on the ground at different locations. The blocks fell down onto a terrace, 120 m below the release zone. The impact generated a small continuous mass movement composed of a mixture of rocks, sand and dust that ran down the slope and impacted on the road 60 m below. Time, time-frequency evolution and particle motion analysis of the seismic records and seismic energy estimation were performed. The results are as follows: 1 ¿ A rockfall event generates seismic signals with specific characteristics in the time domain; 2 ¿ the seismic signals generated by the mass movement show a time-frequency evolution different from that of other seismogenic sources (e.g. earthquakes, explosions or a single rock impact). This feature could be used for detection purposes; 3 ¿ particle motion plot analysis shows that the procedure to locate the rock impact using two stations is feasible; 4 ¿ The feasibility and validity of seismic methods for the detection of rockfall events, their localization and size determination are comfirmed.

Guidelines for County Engineering Decisions, HR-369, 1997

There has been a great deal of concern by county engineers and supervisors over constrained budgets, lack of resources and a deteriorating infrastructure, as they affect the secondary road system in Iowa. In addition, public input and/or political pressure have been increasing over the years. This study was initiated to determine the most important issues facing counties and document the way in which various Iowa counties have been addressing those issues. The list of issues was developed through meetings of county engineers and supervisors in each of the Iowa Department of Transportation (DOT) regions around the state. Questionnaires were sent to all engineers and supervisors statewide asking them how the various issues (e.g. snow and ice removal policies, Level "B" roads, and so on) were handled in their respective counties. The responses were then compiled into this document. The subjects selected and used include: county policies, ordinances, resolutions; snow and ice removal policy; dust control; Level "B" roads; vacating roads; rural development; private entrance construction and maintenance; roadside management practices; right of way encroachments and easements; personnel matters, staff and organization; communicating information to citizens; supervisor/ engineer relations; and county leasing/purchasing practices.

Low Cost Techniques of Base Stabilization, HR-312, 1994

This project was initiated in 1988 to study the effectiveness of four different construction techniques for establishing a stable base on a granular surfaced roadway. After base stabilization, the roadway was then seal coated, eliminating dust problems associated with granular surfaced roads. When monies become available, the roadway can be surfaced with a more permanent structure. A 2.8 mi (4.5 km) section of the Horseshoe Road in Dubuque County was divided into four divisions for this study. This report discusses the procedures used during construction of these different divisions. Problems and possible solutions have been analyzed to better understand the capabilities of the materials and construction techniques used on the project. The project had the following results: High structural ratings and soil K factors for the BIO CAT and Consolid bases did not translate to good roadway performance; the macadam base had the best overall performance; the tensar fabric had no noticeable effect on the macadam base; and the HFE-300 performed acceptably.

Exposure to bioaerosols in poultry houses at different stages of fattening; use of real-time PCR for airborne bacterial quantification

Previous studies have demonstrated that poultry house workers are exposed to very high levels of organic dust and consequently have an increased prevalence of adverse respiratory symptoms. However, the influence of the age of broilers on bioaerosol concentrations has not been investigated. To evaluate the evolution of bioaerosol concentration during the fattening period, bioaerosol parameters (inhalable dust, endotoxin and bacteria) were measured in 12 poultry confinement buildings in Switzerland, at three different stages of the birds' growth; samples of air taken from within the breathing zones of individual poultry house employees as they caught the chickens ready to be transported for slaughter were also analysed. Quantitative polymerase chain reaction (Q-PCR) was used to assess the quantity of total airborne bacteria and total airborne Staphylococcus species. Bioaerosol levels increased significantly during the fattening period of the chickens. During the task of catching mature birds, the mean inhalable dust concentration for a worker was 26 +/- 1.9 mg m(-3) and endotoxin concentration was 6198 +/- 2.3 EU m(-3) air, >6-fold higher than the Swiss occupational recommended value (1000 EU m(-3)). The mean exposure level of bird catchers to total bacteria and Staphylococcus species measured by Q-PCR is also very high, respectively, reaching values of 53 (+/-2.6) x 10(7) cells m(-3) air and 62 (+/-1.9) x 10(6) m(-3) air. It was concluded that in the absence of wearing protective breathing apparatus, chicken catchers in Switzerland risk exposure beyond recommended limits for all measured bioaerosol parameters. Moreover, the use of Q-PCR to estimate total and specific numbers of airborne bacteria is a promising tool for evaluating any modifications intended to improve the safety of current working practices

Gradation Analysis of Cold Feed and Extracted Bituminuous Mix Samples, MLR-88-2, 1988

Since 1987, the Iowa Department of Transportation has based control of hot asphalt concrete mixes on cold feed gradations. This report presents results of comparisons between cold feed gradations and gradations of aggregate from the same material after it has been processed through the plant and laydown machine. Results are categorized based on mix type, plant type, and method of dust control, in an effort to quantify and identify the factors contributing to those changes. Results of the report are: 1. From the 390 sample comparisons made, aggregate degradation due to asphalt plant processing was demonstrated by an average increase of +0.7% passing the #200 sieve and an average increase in surface area of +1.8 sq. ft. per pound of aggregate. 2. Categories with Type A Mix or Recycling as a sorting criteria generally produced greater degradation than categories containing Type B Mixes and/or plants with scrubbers. 3. None of the averages calculated for the categories should be considered unacceptably high, however, it is information that should be considered when making mix changes in the field, selecting asphalt contents for borderline mix designs, or when evaluating potential mix gradation specification or design criteria changes.

Recycled Asphalt Pavements - Kossuth County Iowa, HR-176, 1975

Kossuth County is located in North Central Iowa bordering on the State of Minnesota. It is the largest county in Iowa consisting of 28 congressional townships. The population of the county is 23,000 of which 11,000 people live in the rural area. There are 13 towns located in the county with the county seat, Algona, being the largest with a population of 6,100. Major industry of the area is grain farming with some beef and hog production. Naturally, where there is good grain farm land it follows that there is poor soil available for road construction and pavements. However, below the 3 to 4 feet of good farm land of Kossuth there is present a good grade of clay soil which does make an adequate base for surfacing when placed and compacted on top of the roadbed. As early as 1950, the then Kossuth County Engineer, H.M. Smith, embarked on a program of stage construction in building new grades and pavements. The goal of his program was primarily to conserve the county's rapidly dwindling supply of surfacing materials, and also, to realize the side effects of providing smooth and dustless roads for the public. Engineer Smith was fully aware of the poor soils that existed for road construction, but he also knew about the good clay that lay below the farm soil. Consequently, in his grading program he insisted that road ditches be dug deep enough to allow the good clay soil to be compacted on top of the roadbed. The presence of the compacted clay on top of the road resulted in a briding affect over the farm soil. The stage construction program satisfied the objectives of aggregate construction and dust control but did generate other problems which we are now trying to solve as economically as possible.

The farmer's lung disease : occupational medicine input

Background: Although there has been an abundant literature in recent years about farmer's lung disease, few addressed occupational measures able to maintain the farmer in his work. Nevertheless we know now that most of the farmers can be kept at the workplace by the way of occupational preventive measures. Methods: This matter is discussed from a case report. A farmer affected by the farmer's lung disease was sent to us by his pneumologist, in order to estimate the possibility of maintaining him in his job and to determine relevant changes at his workplace to minimize risk of exposure to dust antigen. This approach required a visit to the workplace by occupational physician and hygienist. Results: The visit of the workplace pointed out different habits and architectural particularities which were potential sources of exposure. The two main proposed measures to reduce the risk, were to wear respiratory masks while working inside the barn, such as preparing hay, feeding the cattle or sweeping the floor, and to build a direct access from the bathroom (shower and toilet) to the outside, allowing to go out of the barn after taking a shower and changing, without risk of being contaminated again. Although upgrading the shower-toilet is not yet completed to date, the already performed modifications led currently to significant clinical improvements, despite the risk of exposure was high since the animals were in the barn for more than two months. Conclusion: The treatment of the farmer's lung disease must be multidisciplinary involving general practitioner, pneumologist, occupational hygienist and occupational physician.

H2O-δD-Fe-III relations of dehydrogenation and dehydration processes in magmatic amphiboles

Stable isotope compositions of a suite of magmatic amphiboles from alkaline basalts and andesitic rocks were examined to constrain the effects of degassing processes on the hydrogen isotope compositions. The Fe3+ (as Fe3+/Fe-total) and H2O contents, as well as the H isotope compositions of the amphiboles, differ markedly (27-58%, 0.5-2.2 wt%, -107 to -15 parts per thousand, respectively) but indicate systematic variations. The observed trends can be explained either as dehydrogenation or dehydration processes, both of which are coupled to oxidation processes, the latter most probably related to O2- substitution within amphiboles. The dehydrogenation-dehydration models can be used to assess the primary compositions of the magmas. As an important example, delta D values of amphiboles of Martian meteorites are discussed in a similar context. Copyright (c) 2006 John Wiley & Sons, Ltd.

Water planning law and government.

Water planning efforts typically identify problems and needs. But simply calling attention to issues is usually not enough to spur action; the end result of many well-intentioned planning efforts is a report that ends up gathering dust on a shelf. Vague recommendations like “Water conservation measures should be implemented” usually accomplish little by themselves as they don’t assign responsibility to anyone. Success is more likely when an implementation strategy — who can and should do what — is developed as part of the planning process. The more detailed and specific the implementation strategy, the greater the chance that something will actually be done. The question then becomes who has the legal authority or responsibility to do what? Are new laws and programs needed or can existing ones be used to implement the recommendations? ... This document is divided into four main parts. The first, “Carrots and Sticks” looks at two basic approaches — regulatory and non-regulatory — that can be, and are, used to carry out water policy. Both have advantages and disadvantages that need to be considered. The second, “The powers of federal, state and local governments…,” looks at the constitutional powers the federal government and state and local governments have to carry out water policy. An initial look at the U. S. Constitution might suggest the federal government’s regulatory authority over water is limited but, in fact, its powers are very substantial. States have considerable authority to do a number of things but have to be mindful of any federal efforts that might conflict with those state efforts. And local governments can only do those things the state constitution or state legislature says they can do and must conform to any requirements or limitations on those powers that are contained in the enabling acts. Parts three and four examine in more detail the main programs and agencies at the federal level as well as Iowa’s state and local levels and the roles they play in national and state water policy.

Crushed Stone Granular Surfacing Materials, HR-2046 and MLR-90-07, 1990

This project included the following tasks: (1) Preparation of a questionnaire and survey of all 99 Iowa county engineers for input on current surfacing material practice; (2) County survey data analysis and selection of surfacing materials gradations to be used for test road construction; (3) Solicitation of county engineers and stone producers for project participation; (4) Field inspection and selection of the test road; (5) Construction of test road using varying material gradations from a single source; and (6) Field and laboratory testing and test road monitoring. The results of this research project indicate that crushed stone surfacing material graded on the fine side of Iowa Department of Transportation Class A surfacing specifications provides lower roughness and better rideability; better braking and handling characteristics; and less dust generation than the coarser gradations. It is believed that this material has sufficient fines available to act as a binder for the coarser material, which in turn promotes the formation of tight surface crust. This crust acts to provide a smooth riding surface, reduces dust generation, and improves vehicle braking and handling characteristics.