Optimisation of olive oil phenol extraction conditions using a high-power probe ultrasonication.

A new method of ultrasound probe assisted liquid-liquid extraction (US-LLE) combined with a freeze-based fat precipitation clean-up and HPLC-DAD-FLD-MS detection is described for extra virgin olive oil (EVOO) phenol analysis. Three extraction variables (solvent type; 100%, 80%, 50% methanol, sonication time; 5, 10, 20 min, extraction steps; 1-5) and two clean-up methods (n-hexane washing vs. low temperature fat precipitation) were studied and optimised with aim to maximise extracts' phenol recoveries. A three-step extraction of 10 min with pure methanol (5 mL) resulted in the highest phenol content of freeze-based defatted extracts (667 µg GAE g(-1)) from 10 g of EVOO, providing much higher efficiency (up to 68%) and repeatability (up to 51%) vs. its non-sonicated counterpart (LLE-agitation) and n-hexane washing. In addition, the overall method provided high linearity (r(2)≥0.97), precision (RSD: 0.4-9.3%) and sensitivity with LODs/LOQs ranging from 0.03 to 0.16 µg g(-1) and 0.10-0.51 µg g(-1) of EVOO, respectively.

Energy expenditure and clearing snow: a comparison of shovel and snow pusher.

In order to assess the energy demands of manual clearing of snow, nine men did snow clearing work for 15 min with a shovel and a snow pusher. The depth of the snowcover was 400-600 mm representing a very heavy snowfall. Heart rate (HR), oxygen consumption (VO2), pulmonary ventilation (VE), respiratory exchange ratio (R), and rating of perceived exertion (RPE) were determined during the work tasks. HR, VE, R, and RPE were not significantly different between the shovel and snow pusher. HR averaged (+/- SD) 141 +/- 20 b min-1 with the shovel, and 142 +/- 19 beats.min-1 with the snow pusher. VO2 was 2.1 +/- 0.41.min-1 (63 +/- 12%VO2 max) in shovelling and 2.6 +/- 0.51.min-1 (75 +/- 14%VO2max) in snow pushing (p < 0.001). In conclusion manual clearing of snow in conditions representing heavy snowfalls was found to be strenuous physical work, not suitable for persons with cardiac risk factors, but which may serve as a mode of physical training in healthy adults.

Accident locus of control and risk taking among forestry and construction workers.

228 forestry and 45 construction workers completed the Accident Locus of Control scale which is a modified version of the Health Locus of Control inventory. The forestry workers scored as having a more external locus of control than the construction workers. In both professional groups the subjects with higher scores on external locus of control tended to take more risks than the subjects with higher scores on internal locus of control. The results support a dual-dimensional view of control rather than a unidimensional view.

Accidents in the Arctic. A psychological point of view.

The aim of this paper is to discuss the influence of arctic conditions on the occurrence of accidents especially from the point of view of the interaction between environment, activity and man. Special attention is paid to risk assessment, risk taking and risk compensation. According to the danger factor theory frostbites should be extremely common in arctic regions, but in reality serious frostbites appear rarely in accident statistics. This finding supports the interactive accident theories. Instead cold can be a contributing factor in accident and injury causation and the effect of cold is most often indirect. Frostbites can occur e.g. as a result of an accident, losing one's way because of darkness, snow storm etc., wet clothes, unexpected temperature changes, disease attack, alcohol-induced reasons such as immobility or excess risk taking etc. Temperatures below and above +20 degrees C increase unsafe behavior. In the Arctic it is impossible to remove all the potentially dangerous factors, because many typical features of working and living conditions are regulated by natural forces, the seasons etc. This makes accurate risk assessment and prediction especially important in accident prevention. If the person does not recognize the situations in which the risk factors exist, he/she cannot implement precautionary steps at the right moment and hence cannot avoid risks. Moreover, if better and safer machines, equipment and tools get people to take greater risks, the accident situation can even become worse.

The physical strain of dairy farming.

The aim of this study was to estimate the physical stress and strain in diary farming, using ambulatory heart rate and oxygen consumption measurements. The rate of perceived exertion was estimated with Borg scale. The maximal oxygen consumption was measured in the laboratory. The study group consisted of eight male and 15 female farmers. The handling of feed and manure was the heaviest work task in dairy farming. The aerobic capacity (VO2 max) of female farmers (26 +/- 3 ml/min/kg) was below average, and their work required over 50% of VO2 max during most of the tasks. The VO2 max of male farmers (32 +/- 10 ml/min/kg) was moderate, and most work tasks required below 50% of VO2 max. The mean heart rate in dairy farming tasks was 99 beats min-1 in men and 116 beats min-1 in women. However, according to the rate of perceived exertion, the mean experienced the same work tasks as subjectively more heavy than did the women. The physical strain of female farmers in dairy farming seems to be too high because of heavy work tasks and relatively low VO2 max of women. Special attention should be paid to these factors in the occupational health services for farmers.

Cardiorespiratory strain during walking in snow with boots of different weights.

In order to assess the physiological strain of different boot weights, seven male and three female subjects walked on a treadmill and a snow-field while wearing three types of boots: winter jogging boots (WJB), rubber boots (RB), and rubber safety boots (RSB), weighing (means +/- s.d.) 0.9 +/- 0.1, 1.9 +/- 0.4 and 2.5 +/- 0.2 kg, respectively During each walk the subjects wore the same clothing ensembles and moved at the same, individually determined speed. The mean (+/- s.e.) depths of the footprint impression in the snow while walking in the WJB, RB, and RSB were 26.1 +/- 1.5, 25.6 +/- 1.4 and 26.1 +/- 1.5 cm (NS), respectively. During walking on the treadmill, the means for oxygen consumption were 0.79 +/- 0.05, 0.81 +/- 0.06 and 0.83 +/- 0.04 l min-1 (NS) and in snow 2.24 +/- 0.18, 2.34 +/- 0.17 and 2.34 +/- 0.19 l min-1 (p less than 0.01) with the WJB, RB and RSB, respectively. The mean oxygen consumption levels observed during the walks averaged 23% and 65% of the subject's maximum oxygen consumption on the treadmill and in the snow-field, respectively. During the walking tests the corresponding mean heart rates were 106 +/- 4, 93 +/- 5, and 95 +/- 5 beats min-1 (p less than 0.05) on the treadmill, and 151 +/- 11, 150 +/- 11 and 151 +/- 12 beats min-1 (NS) in snow. No significant differences in ratings of perceived exertion were observed between the walking tests in snow with the three types of boots. In accordance with earlier studies, walking in snow was found to be strenuous work. In conclusion, the use of the RSB is recommended during logging work in snow, since they are known to provide greater protection than lighter boots and the increase in physiological strain experienced with RSB in this study was not appreciably greater than that with boots of lighter weight.

Evaluation of comfort and seal leakages of several respirators used in agricultural work.

Certain aspects in the use of some respiratory protective devices were studied under laboratory and field conditions. The face seal leakages of these devices were measured and volunteers were interviewed about their subjective opinions on the use of the devices. Twelve men and five women participated in the study. The models tested were Silner 12, Siltox, Sundstrom SR 62/80, Airstream Breath Easy 2, Pirelli, and 3M (8810 P2, disposable) which are used in agricultural work in Finland. According to the study's results, these four models significantly differed from each other regarding the facial seal leakage (p less than 0.01). The Silner 12 had the greatest seal leakage (5.9% with men and 5.2% with women). The subjects felt that these respiratory protective devices were not cumbersome in their agricultural work or in the laboratory tests. The comfort of these devices in practical work was about the same for all models. Powered filtering hoods were more pleasant to use than mechanical ones because they offered less breathing resistance. The volunteers complained that with the Breath Easy 2 they felt drafts on the backs of their heads, especially while working in cool weather.

Storage mites in the work environment of farmers.

Occurrence of storage mites was studied in cow houses and hay stores on 19 farms, most of which were located in eastern Finland. On two farms we did a monthly follow-up. Mites were extracted from hay by sieving, using the so-called "water trap" and for longitudinal analysis, with a warm extractor. The mites isolated in the water trap were identified under a microscope. Contrary to previous Finnish findings, there apparently were more mites in cow houses than in hay stores. In cow houses there were an average of 1,650 mites per gram of dust and in hay stores about 1,100 mites per gram of dust. Acarus siro was most abundant in cow houses (67% of all the mites found in cow houses) and more than 1,000 mites/g of sample material. The second most numerous was Tydeus spp. (178 mites/g of sample material). After that, Lepidoglyphus destructor, Tyrophagus longior, Glycyphagus domesticus occurred in about equal numbers. In hay stores Tydeus spp. was slightly more common (341 mites/g of sample material) than Acarus siro (317 mites/g of sample material). Lepidoglyphus destructor (64 mites/g of sample material), Glycyphagus domesticus (60 mites/g of sample material) and Mesostigmata (57 mites/g of dust) occurred in about equal numbers. According to the analysis based on one farm the number of mites in hay stores decreased considerably from September to February. Based on four measurements in the cow house of another farm, however, no steady trend of longitudinal variation could be found. Mites were most abundant at the beginning of January. There were few or no mites in bales of dry and unmoulded hay.

The protective influence of logger's safety equipment.

The effects of loggers' personal protectors and the safety equipment of chain saws were investigated with a postal questionnaire. The sample included 1,200 loggers. The main purpose of the inquiry was to collect data on accidents and near-accidents; special attention was paid to the role and behavior of protective devices in both accident and near-accident situations. Twenty-seven percent of power saw operators reported incidents (near-accidents) which had occurred within the last year and in which some personal protector or piece of safety equipment had prevented harmful mechanical contact. The workers estimated that the average absence from work due to these reported near-accidents would have been 15 workdays if the injury had not been prevented. Sixty percent of the near-accidents occurred during limbing operations, and 30% during falling. The protective equipment which most often prevented injuries was safety boots, which were followed by the safety helmet and leg protectors. The chain of the saw was stopped by the safety padding of the protective equipment in every other near-accident involving chain saws. The chain was blocked by padding material in every sixth situation . In 10% of the near-accidents, the chain perforated the protective equipment.