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PubMed2006

Impact of software and hardware technologies on occupational health and safety policies in Saudi Arabian oil refineries.

This article seeks to examine the impact of technology importation on occupational health and safety in both Saudi Arabian and U.S. oil refining industries. Technologies imported to the Saudi oil industry take two forms: hardware (sophisticated equipment to run oil facilities) and software (policies and regulations pertaining to workers' health and safety, and employment rights installed by Aramco's founding multinational companies). This study utilizes qualitative, historically oriented, cross-national case studies to compare and assess workers' health, safety, and rights in Saudi Aramco with its U.S. counterpart, Motiva Enterprises. Two facilities were chosen to conduct field research: the Saudi Aramco oil refinery at Jeddah and Motiva's refinery at Port Arthur, Texas. The Jeddah refinery is fully owned by Saudi Aramco, thus, representing Aramco's health and safety policies and regulations. The Port Arthur refinery serves as a reference case study for U.S. oil refining facilities. The aspects of occupational health and safety in Saudi Aramco--ExxonMobil's joint ventures SAMREF and LUBREF--also are discussed to examine workers' health policies in both companies. The American oil industry made a significant contribution in establishing the Saudi oil industry, with the cooperation of the Saudi government. Despite having outstanding employment benefits schemes in Saudi Aramco, the presence of an organized work force better serves employee participation in Motiva than in Aramco. Safety systems such as Process Safety Management (PSM)--applied in Motiva--partially exist in Aramco to operate hardware technologies safely. Motiva training systems are better through PACE's Triangle of Prevention (TOP). Both companies follow the same pattern of handling occupational injuries and diseases; however, Saudi government agencies (GOSI) are responsible for compensating and treating injured workers. Saudi workers expressed conditional support for the worker committee program proposed by the Ministry of Labor. American and Saudi workers are concerned about the quality and sufficiency of health and safety training, employment promotion, work pressure, and job uncertainty due to continuous downsizing. This article recommends that Saudi social actors increase safety and health awareness in the work environment by providing intensive occupational safety training to the employees (as demanded by Saudi and American workers), improve labor-management relations through establishing strong cooperative contacts with regional and international trade unions, and establish uniform and standard occupational health and safety regulations for Saudi Aramco and its subsidiaries in order to provide an equal level of protection for Saudi workers.

Accidents, Occupational↗

PubMedDate not supplied

Benzene and total hydrocarbon exposures in the upstream petroleum oil and gas industry.

Occupational exposures to benzene and total hydrocarbons (THC) in the Canadian upstream petroleum industry are described in this article. A total of 1547 air samples taken by 5 oil companies in various sectors (i.e., conventional oil/gas, conventional gas, heavy oil processing, drilling and pipelines) were evaluated and summarized. The data includes personal long- and short-term samples and area long-term samples. The percentage of samples over the occupational exposure limit (OEL) of 3.2 mg/m3 or one part per million for benzene, for personal long-term samples ranges from 0 to 0.7% in the different sectors, and area long-term samples range from 0 to 13%. For short-term personal samples, the exceedance for benzene is at 5% with respect to the OEL of 16 mg/m3 or five parts per million in the conventional gas sector and none in the remaining sectors. THC levels were not available for all sectors and had limited data points in others. The percentage exceedance of the OEL of 280 mg/m3 or 100 parts per million for THC as gasoline ranged from 0 to 2.6% for personal long-term samples. It is recommended that certain operations such as glycol dehydrators be carefully monitored and that a task-based monitoring program be included along with the traditional long- and short-term personal exposure sampling.

Benzene↗

PubMed2004

The blight of pollution keratoconjunctivitis among children in oil-producing industrial areas of Delta State, Nigeria.

The rapid urbanization and industrialization of Warri and environs between 1968 and 1990 have some adverse consequences due to accumulation of diverse categories of pollutants from drilling, production, and refining of crude oil and production of petrochemicals, especially black carbon. Persistent itching, foreign body sensation, and specified areas of conjunctival/limbal discoloration were used as markers for pollution keratoconjunctivitis (PKC). Children attending eye clinics in Delta State government hospitals located at Warri, Ekpan, and Aladja were sampled. Warri and Ekpan, both oil-producing areas, were used as the experimental group. Aladja, also within the same location but a nonoil-producing area (steel industries), was used as the control. The levels of black carbon and tetraethyl lead (TEL) were measured in the tear film of 100 children selected by a simple random technique from each location. Biochemical assays showed that the tear samples contained some levels of TEL among the sample population, and the TEL content was 0.01 microg/mL for all the tear samples. Stereomicroscopy gave the following estimated values of black carbon content washed off the external adnexia of the sample population: Ekpan 2%/mL, Warri 1.5%/mL, and Aladja 0.6%/mL. The results also show that occurrence of the three major clinical signs and symptoms of PKC (persistent itching, foreign body sensation, specified limbal/conjunctival discoloration, respectively) were as follow: Ekpan, 79, 68, and 65%; Warri, 55, 53, and 50%; Aladja, 26, 22, and 16%. This indicates that higher particulate concentrations of black carbon correlated with increased prevalence of the markers for manifestation of PKC. This implies that the markers for PKC in this experiment are more pronounced in oil-producing areas.

Adolescent↗

PubMed2004

Inorganic raw materials economy and provenance of chipped industry in some stone age sites of northern and central Italy.

An opportunistic and local choice of raw materials is typically attested in the Lower and Middle Paleolithic industries throughout Italy. The quality of the raw material usually affected the flaking technology and quality of the products. In the Upper Paleolithic and the Mesolithic, raw material procurement strategies were more complex. Flint was exploited both locally, in areas where abundant outcrops of raw materials were available (such as the Lessini mountains), and in distant localities, after which it was transported or exchanged over medium/long distances. Different routes of exchange were thus followed in the various periods; good reconstruction of these routes have been provided by a study of the Garfagnana sites in Northern Tuscany, and the Mesolithic deposit of Mondeval de Sora (Dolomites). An interesting example of a Late Upper Paleolithic flint quarry and workshop were found in Abruzzo, in the San Bartolomeo shelter. The extended trade of obsidian from Lipari, Palmarola and Sardinia to the Italian Peninsula is attested in the Neolithic, with some differences concerning the age and different areas.

Archaeology↗

PubMed2001

Breath-holding ability of offshore workers inadequate to ensure escape from ditched helicopters.

BACKGROUND: Following a helicopter ditching in water, the survival rate of individuals not mortally injured by the impact ranges from 50-85%. One possible cause for this low survival rate is that the crew and passengers cannot hold their breath underwater long enough to make the often difficult escape from an inverted and submerged helicopter. METHODS: We investigated pulmonary function, breath-holding times in air (BHTa) and water (BHTw) of 228 students enrolled in offshore survival courses required to work in either the offshore petroleum industry or in military marine aviation. Comparisons were performed based on occupation, SCUBA experience, and smoking. RESULTS: In 25 degrees C pool water, the overall BHTw ranged from 5.4 to 120 s with a median of 37 s. Of the 228 subjects, 34% had a BHTw less than the 28 s required for the complete evacuation of a Super Puma helicopter under ideal conditions. No significant differences in BHTw were observed based on either smoking history (Non-Smoker, 41.5 +/- 21.6 s; Smoker, 37.2 +/- 20.2 s) or occupation (Novice, 37.5 +/- 21.1 s; Offshore, 40.5 +/- 21.1 s; Military, 45.2 +/- 20.9 s). However, SCUBA-trained individuals had a significantly longer BHT, (47.4 +/- 21.6 s) than non-SCUBA (37.6 +/- 20.6 s), as well as a greater force vital capacity (FVC), BHTa, and subjective comfort in water. CONCLUSIONS: It is concluded that the inability to breath-hold in emergency situations is a major contributor to the low survival rates of marine helicopter ditchings. Therefore, efforts must be made to both decrease escape times and to increase survival time underwater.

Accidents, Aviation↗

PubMed2002

Fluoride content by ion chromatography using a suppressed conductivity detector and osmolality of bitterns discharged into the Pacific Ocean from a saltworks: feasible causal agents in the mortality of green turtles (Chelonia mydas) in the Ojo de Liebre lagoon, Baja California Sur, Mexico.

On December 1997, 94 corpses of green turtles, Chelonia mydas, were found at the Ojo de Liebre lagoon (OLL) adjacent to the industrial operation of Exportadora de Sal S. A (ESSA), the largest saltworks in the world, owned by the Mexican Government and Mitsubishi Corporation, located in Baja California Sur, Mexico. Every year about 551 x 10(6) m3 of seawater is solar evaporated, producing 7 x 10(6) tons of salt and 24.6 x 10(6) m3 of bitterns, the latter being discharged into the OLL, which is a costal lagoon of the Pacific Ocean. ESSA claimed that bitterns contain the same salts present in seawater, but 20-fold more concentrated than the former. Ion chromatography with a conductivity detector and ion suppression was used to determine the F-, Cl-, SO4(2-) and CO3(2-) contents of seawater, brines and bitterns collected at ESSA. Furthermore, the osmolality of brines and bitterns from ESSA was measured. F- content in bitterns was 60.5-fold more than that in seawater. The bitterns osmolality was 11,000 mosm/kg of water, whereas the turtle's plasma osmolality was about 400 mosm/kg of water. We concluded that the dumping of bitterns into the ocean should be avoided.

Animals↗

PubMed2004

Source profiles for industrial, mobile, and area sources in the Big Bend Regional Aerosol Visibility and Observational study.

Representative PM2.5 and PM10 source emissions were sampled in Texas during the Big Bend Regional Aerosol Visibility and Observa (BRAVO) study. Chemical source profiles for elements, ions, and carbon fractions of 145 samples are reported for paved and unpaved road dust, soil dust, motor vehicle exhaust, vegetative burning, four coal-fired power stations, an oil refinery catalytic cracker, two cement kilns, and residential meat cooking. Several samples were taken from each emitter and source type, and these were averaged by source type, and in source subgroups based on commonality of chemical composition. The standard deviation represents the variability of the chemical mass fractions. BRAVO profiles differed in some respects from profiles measured elsewhere. High calcium abundances in geological dust, high selenium abundances in coal-fired power stations, and high antimony abundances in oil refinery catalytic cracker emissions were found. Abundances of eight thermally evolved carbon fractions [Atmos. Environ. 28 (15) (1994) 2493] differ among combustion sources, and a Monte Carlo simulation demonstrates that these differences are sufficient to differentiate among several carbon-emitters.

Air Pollutants↗

PubMed2005

Characterization of dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the atmosphere of different workplaces of a sinter plant.

This study investigated concentrations, contents and congener profiles of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the workplaces of a sintering plant. Air samples were collected from the charging zone, the sintering zones of the sintering grate and the rough roll shredder, and the control room. The charging zone was found to have a higher total suspended particulate (TSP) but lower PCDD/F concentrations (=4969 microg nm(-3) and 7.61 pg nm(-3), respectively) than the sintering zone (=1422-1448 microg nm(-3) and 19.16-23.17 pg nm(-3), respectively). The TSP and PCDD/F concentrations were lowest in the control room (=98 microg nm(-3) and 1.75 pg nm(-3), respectively). However, the above concentrations were within the range of a typical urban-industrial area. Quite similar PCDD/F contents were found in particles in the sintering zones and control room (=11.72-14.30 and 15.85 ng g(-1), respectively) suggesting that the sintering zone and the control room are very similar. In both charging and sintering zones, 2,3,4,7,8-PeCDF contributed 40-60% to the total I-TEQ in both the gas phase and particle phase. However, in control room, both congeners 2,3,4,7,8-PeCDF and 2,3,7,8-TCDD were the main contributors; the later contributed 30% of the total I-TEQ in gas phase. In control room, the contribution of 2,3,7,8-TCDD to the total PCDD/F concentration in the gas phase greatly exceeded that in particle phase (=5.5% and 0.8%, respectively). Therefore, solutions must be sought to avoid the transfer of not only the particle-phase but also the gas-phase PCDD/Fs from the sintering zone to the control room in the future.

Air Pollutants↗

PubMed2005

[Effects of occupational stress on immunological function, glucose and blood lipid of female workers in oil-field].

OBJECTIVE: To study the effects of occupational stress on immunological function, glucose, and blood lipid of female workers in oil-field. METHODS: 900 female workers working in oil-field as observation group and 220 female not working in oil-field in 11 work types of oil industry in oil-field were selected as control group randomly, occupational role, personal strain, and personal abilities of two groups were measured with occupational stress inventory-revised (OSI-R). Then, 100 workers were selected randomly from two groups Blood lipid, blood sugar, and immunological function were measured. RESULTS: Occupational role and strain in observed group are significantly higher than control group (P < 0.05), However, there is no difference on personal abilities in two groups. Blood sugar, IgG, IgA, IgM, IL-6 content in observation group was significantly higher than control group, but CHO, HDL, LDL, IL-2 content was significantly less than control group (P < 0.05). TG content had no significant difference between both groups. There was positive correlation between occupational role, strain and, blood sugar, immunological function but negative correlation between personal abilities (P < 0.05). CONCLUSION: The results show that blood sugar content was increased, CHO, HDL, LDL were decreased and immumological function was changed because of occupational stress. There was positive correlation between occupational role, strain and blood sugar, immunological function but negative correlation between personal resources.

Adult↗

PubMed2003

Environmental pollution in rural areas of Orissa state due to industrial emissions--with special reference to fluoride.

Angul - Talcher belt in Central Orissa, having a number of industries contributing to a great extent to deteriorate the air quality of the surrounding villages. Previous reports showed higher SPM, SO2, NO, levels in air and prevalence of respiratory illness, skin and teeth disorders among village population. Higher ground water fluoride, urine and serum fluoride among the cattle were also reported in some villages. Present study reports SPM, SO2, NOx and Fluorides (gaseous and Particulate) in ambient air around aluminium smelter during February and August 1996. High volume sampling technique for SPM and the standard colorimetric methods (BIS) for analyses of SO2 and NOx were adopted. Fluoride in air and water were estimated by standard fluoride ion selective electrode method. Higher SPM, SO2 and NOx values than prescribed CPCB standard were obtained in February. Gaseous fluoride in village air were varied between, 1.66 - 7.64 mg/m3 in February and 1.11 - 22.75 mg/m3 in August, whereas particulate fluoride ranged between, 0.054 - 19.61 mg/m3. Water sources of the villages near the smelter showed fluoride values above permissible limit. The study indicated higher fluoride pollution in air and water of the surrounding villages.

Air Movements↗

PubMed2006

Update of mortality and cancer incidence in the Australian petroleum industry cohort.

OBJECTIVES: To update the analysis of the cohort mortality and cancer incidence study of employees in the Australian petroleum industry. METHODS: Employees of Australian Institute of Petroleum member companies were enrolled in the cohort in four industry-wide surveys between 1981 and 1999. Mortality of 16,547 males and 1356 females was determined up to 31 December 2001 and cancer incidence to 31 December 2000. Cause specific mortality and cancer incidence were compared with those of the Australian population by means of standardised mortality ratios (SMRs) and standardised incidence ratios (SIRs). Associations between increased incidence of specific cancers and employment in the petroleum industry were tested by trends according to period of first employment, duration of employment, latency, and hydrocarbon exposure, adjusting for personal smoking history where appropriate. RESULTS: There was a significant elevation of the incidence of mesothelioma (SIR 1.77, 95% CI 1.05 to 2.79), melanoma (SIR 1.37, 95% CI 1.19 to 1.58), and prostate cancer (SIR 1.18, 95% CI 1.04 to 1.34). The SIRs of all leukaemias and of acute non-lymphocytic leukaemia (ANLL) were not significantly different from unity, but all 11 ANLL cases were clustered in the middle to high hydrocarbon exposure categories. Tanker drivers had a significantly elevated incidence of kidney cancer (12 cases v 5.84 expected, SIR 2.05, 95% CI 1.06 to 3.59). Lung cancer incidence was significantly reduced (SIR 0.69, 95% CI 0.57 to 0.83) CONCLUSIONS: Most cases of mesothelioma are probably related to past exposure to asbestos in refineries. No occupational cause has been identified for the excess of melanoma, or prostatic or bladder cancer. The possibility of a causal relationship between cancer of the kidney and hydrocarbon exposure warrants further study. It is uncertain whether benzene exposures, particularly past levels of exposure, have been high enough to cause ANLL.

Australia↗

PubMed2001

Lung cancer among industrial sand workers exposed to crystalline silica.

In 1997, the International Agency for Research on Cancer determined that crystalline silica was a human carcinogen but noted inconsistencies in the epidemiology. There are few exposure-response analyses. The authors examined lung cancer mortality among 4,626 industrial sand workers, estimating exposure via a job-exposure matrix based on 4,269 industrial hygiene samples collected in 1974--1995. The average length of employment was 9 years, and estimated average exposure was 0.05 mg/m(3) (the National Institute of Occupational Safety and Health Recommended Exposure Limit). Results confirmed excess mortality from silicosis/pneumoconioses (standardized mortality ratio = 18.2, 95% confidence interval: 10.6, 29.1; 17 deaths). The lung cancer standardized mortality ratio was 1.60 (95% confidence interval: 1.31, 1.93; 109 deaths). Limited data suggested that smoking might account for 10--20% of the lung cancer excess. Exposure-response analyses by quartile of cumulative exposure (15-year lag) yielded standardized rate ratios of 1.00, 0.78, 1.51, and 1.57 (p for trend = 0.07). Nested case-control analyses after exclusion of short-term workers, who had high overall morality, yielded odds ratios by quartile of cumulative exposure (15-year lag) of 1.00, 1.35, 1.63, and 2.00 (p for trend = 0.08) and odds ratios by quartile of average exposure of 1.00, 0.92, 1.44, and 2.26 (p = 0.005). These data lend support to the labeling by the International Agency for Research on Cancer of silica as a human carcinogen. There are approximately 2 million US workers exposed to silica; 100,000 are exposed to more than 0.1 mg/m(3).

Adult↗

PubMed2003

Overview and characteristics of some occupational exposures and health risks on offshore oil and gas installations.

This review considers the nature, and recognition and control, of health risks in the offshore oil and gas industry from the occupational hygiene point of view. Particular attention is given to the changes in the nature of exposure and control of inhalation risks from substances hazardous to health in the UK sector, but other risks (e.g. dermatitis, noise and vibration) are also considered. The amount of published information on exposure to these hazards in the sector, or indeed on long-term health outcomes of working offshore, is limited. The approach taken to occupational health and hygiene in the sector has to be set in the context of the challenge of working in a remote and hostile environment where attention to safety and the need for emergency response to acute, rather than chronic, medical events are vital. However, changes in attitudes towards occupational health in the sector, legislation, the impact of environmental protection requirements and technology have all contributed to increasing the attention given to assessment and control of chemical and physical hazards. The health risks and benefits associated with the abandonment of installations, the application of new technologies, recovery of oil from ever deeper waters, lower staffing levels, environmental changes, the ageing workforce and the recognition of exposure patterns needing further attention/control (sequential multiple exposures, smaller workforce, peak/short-term exposures, etc.) are other current and future occupational hygiene challenges.

Air Pollutants, Occupational↗

PubMed2006

Obesity and mortality in a prospective study of a middle-aged industrial population.

BACKGROUND: Although obesity is an established risk factor for coronary heart disease and stroke mortality, its role as a risk factor for other causes of death has not been extensively investigated, particularly in an industrial population. METHODS: This prospective mortality study included 20 years of follow up of middle-aged industrial workers (n = 7139) at Shell Oil Company's manufacturing and research facilities. Baseline health risk factor data as of December 31, 1983, and mortality data as of December 31, 2003, were extracted from the company's Health Surveillance System. Relative risks (RRs) for selected causes of death by body mass index (BMI) category were calculated using the Cox proportional hazards model adjusted for age, sex, and smoking status as well as other potential risk factors, ie, cholesterol, hypertension, and fasting blood glucose. RESULTS: Compared with employees with BMI between 18.5 and 24.9 kg/m, those with BMI of 30 kg/m or greater had a statistically increased RR (adjusted for age, sex, and smoking status) for all causes (RR, 1.25; 95% confidence interval [CI] = 1.03-1.51), coronary heart diseases (RR, 2.29; 95% CI = 1.50-3.50), cardiovascular diseases (RR, 2.22; 95% CI = 1.51-3.27), diabetes (RR, 16.97; 95% CI = 2.11-136.44), and accidental deaths (RR, 2.64; 95% CI = 1.23-5.66). After adjusting for additional covariates, coronary heart diseases and cardiovascular diseases remained statistically significant. CONCLUSIONS: Obesity was associated with increased death rates for all causes, cardiovascular diseases, diabetes, and all accidents. Overweight individuals had a statistically lower cancer rate. Death rates for lung cancer and respiratory disease were lower among overweight/obese employees but did not reach statistical significance. Reductions of employee obesity can be an effective means of reducing these causes of death.

Adult↗

PubMed2005

Noise-induced hearing loss is exacerbated by long-term smoking.

OBJECTIVE: To analyse the influence of long-term smoking on the hearing threshold of individuals subjected to occupational noise exposure. DESIGN: Prospective observational cohort study. SETTING: Occupational health examination of noise-exposed employees in the brick manufacturing industry. PARTICIPANTS: A study group of long-term smokers (n = 30) and a control group of non-smokers (n = 58) were identified from a population of 227 male noise-exposed employees. Individuals of both groups were employed for 10 years or more at a single brick manufacturing plant. Data on noise exposure, smoking habits, medical and otological history were collected and standard pure tone audiometry was obtained. Exclusion criteria included asymmetrical or conductive hearing loss, uncontrolled systemic illnesses, history of head injury, chronic middle ear pathology or major ear operations. MAIN OUTCOME MEASURE: Pure tone audiometry. RESULTS: Both groups had similar mean age and total duration of occupational noise exposure. The median age-corrected hearing thresholds at 3 and 4 kHz in the smokers group were significantly higher (approximately 7dB) than those in the non-smokers group. No statistical difference in the hearing thresholds between both groups was found in any other tested frequency (0.5, 1, 2, 6 and 8 kHz). CONCLUSION: Long-term smokers with occupational noise exposure may, on the basis of this limited study, have a higher risk of developing permanent hearing loss at 3 and 4 kHz when compared with non-smokers with a similar occupational history.

Audiometry, Pure-Tone↗

PubMed1999

Ozone-induced respiratory illness during the repair of a portland cement kiln.

OBJECTIVES: Workers at a portland cement plant had experienced acute respiratory and eye irritation when performing maintenance inside a kiln. These episodes were associated with a bleach-like odor, which was only reported during maintenance operations. An industrial hygiene investigation was conducted to determine the cause of the illness. METHODS: While workers replaced refractory brick inside the kiln, air samples were collected for chlorine, sulfur dioxide, inorganic acid, ozone, and dust. After the rebricking was completed and all the workers had exited the kiln, its electrostatic precipitator was reduced to half power and the induced-draft (ID) fan was turned off to recreate conditions present during illness episodes. RESULTS: Chlorine, inorganic acid, and ozone were not detected, and only trace concentrations of sulfur dioxide were detected while workers were inside the kiln. However, when conditions present during previous episodes were recreated, the bleach-like odor was soon evident. Chlorine was not detected, but 0.09 to 0.11 ppm of ozone was measured at the discharge end of the kiln, and 4.5 ppm was measured at the inlet end. Within a half hour after the electrostatic precipitator was turned off and the ID fan was turned on, the ozone concentrations decreased to background levels of 0.02-0.03 ppm. CONCLUSIONS: Somewhat lower ozone exposures may have occurred during previous kiln maintenance operations due to more open access portals, but previous episodes of eye and respiratory irritation were probably caused when ozone, generated by the electrostatic precipitator, back-drafted into the kiln after the ID fan was turned off.

Extraction and Processing Industry↗

PubMed2004

Mycorrhizal inoculum potentials of pure reclamation materials and revegetated tailing sands from the Canadian oil sand industry.

Recent improvements in the management of oil sand tailings used by the Canadian oil sand industry have resulted in the production of composite tailing sands (CT): a new challenging material for reclamation work. Jack pine (Pinus banksiana Lamb.), hybrid poplar (Populus deltoides Bartr. ex Marsh. xPopulus nigra L.) and red clover (Trifolium pratense L.) plants were used in an 8-week greenhouse bioassay to evaluate the mycorrhizal inoculum potential of CT. This inoculum potential was compared with that of three other reclamation materials [common tailing sands (TS), deep overburden (OB) and muskeg peat (MK)], and with three sites reclaimed in 1982 (R82), 1988 (R88) and 1999 (R99). CT was devoid of active mycorrhizal propagules while all other materials showed some level of inoculum potential. Arbuscular mycorrhizal fungi were observed on roots of clover or poplar grown in TS, OB, and all substrates containing peat (MK, R82, R88 and R99). Pine roots were also colonized by vesicle-forming hyphae of an unidentified fine endophyte and by dark septate fungi. Ectomycorrhizas (ECM) were observed on pine and poplar grown in OB, MK, and in soils from the two older reclaimed sites (R82 and R88). Using morpho- and molecular typing, six ECM fungi were identified to the genus or species level: Laccaria sp., Thelephora americana, Wilcoxina sp. (E-strain), Tuber sp. (I-type), a Sebacinoid, and a Pezizales species. Laccaria sp. and Wilcoxina sp. were the most frequently observed ECM species.

Biodegradation, Environmental↗

PubMed2005

Comparison of direct (X-ray diffraction and infrared spectrophotometry) and indirect (infrared spectrophotometry) methods for the analysis of alpha-quartz in airborne dusts.

In this study, the alpha-quartz contents measured by different analytical techniques (X-ray diffraction, direct method; and infrared spectrophotometry, direct and indirect methods) were compared. The analyses were carried out on filters sampled in an industrial setting by means of a Dorr-Oliver cyclone. To verify the methodology used, filters loaded with pure alpha-quartz were also analysed. By and large, the agreement between the two direct methods was close on average, but on the basis of a comparison of the individual results, considerable differences exist. In absolute value, the mean relative deviation between the two techniques was <25% in only 47.8% of the cases. The results obtained by the indirect method (infrared) were on average 13% lower than the results obtained by the two direct methods with a more important difference (23%) for samples where calcite was identified by X-ray diffraction in comparison with those where it was not (8%). This underestimation, which was not owing to dust losses during preparation, is probably explained by the elimination of organic compounds during dust calcinations or by the transformation of mineral compounds. The indirect method introduces additional sample handling operations with more risk of material loss. When the quantity of calcined material was <0.4 mg, the weighing operations necessary to correct any losses of material resulted in considerable variability. In terms of overall uncertainty, it would be better in this case not to carry out correction and to employ an operating mode favouring the recovery of a maximum of material while accepting a bias of about 5-7%.

Air Pollutants↗