Assessment of airborne hazards in the thorium processing industry

Airborne thorium thoron and its decay products contribute significantly to the hazards in the thorium industry. These have been assessed and compared with the standards. Assessment also included the unattached fractions of the decay products, the thoron working levels and the aerodynamic particle size distribution of airborne thorium.     

Surgical hazards posed by marine and freshwater animals in Florida

Marine and freshwater animals can cause injury to humans by biting, stinging, being poisonous to eat, and causing infections. Biting aquatic animals in Florida include sharks, barracudas, alligators, and moray eels. Devitalized tissue should be débrided, and vascular, neurologic, and tendinous injuries should be repaired. Radiographs should be obtained to examine the injury sit for fractures and retained foreign bodies (teeth). The spines of stingrays and marine catfish can cause soft tissue injury and infection. The spine has a recurved, serrated shape that may cause further injury and break if it is pulled out. The venom may cause local tissue necrosis requiring débridement. Soft tissue infections with marine Vibrio bacteria can occur after eating raw oysters or receiving even minor injuries from marine animals. Thirty-one individuals developed soft tissue infections, 49 developed sepsis, and 23 developed both sepsis and soft tissue infection with marine Vibrio species during a 12-year period. Sixteen patients developed necrotizing soft tissue infections. Treatment is with antibiotics and débridement when necrosis occurs.     

Venomous marine animals of Florida: morphology, behavior, health hazards

This article reviews the dangers related to marine animal envenomations in Florida. Venomous marine animals exhibit diverse mechanisms of injury and toxicity. Information regarding the morphology, behavior, and health hazards of these dangerous organisms is presented to help medical personnel recognize, diagnose and treat marine envenomations. Hazardous marine animals discussed in this review include both invertebrates and vertebrates. Stinging invertebrate animals include sponges, coelenterates (jellyfish, hydroids, corals, and sea anemones), echinoderms (sea urchins, starfish and sea cucumbers), annelid worms (bristleworm), and mollusks (cone shells, octopi and nudibranches). Stinging vertebrates discussed include stingrays, catfish, scorpionfish, and leatherjacks.     

Evaluation of health hazards of asbestos containing wastes in the mining industry and prospects of their utilization

The study covered asbestos-containing waste at a major mining enrichment enterprise--"Uralasbest" JSC. A set of methods were used to associate natural human compensatory mechanisms with experimental models simplifying possible routes of asbestos influence on humans and proved no toxic features of the dust studied. The results help to manage removal and storage of asbestos-containing waste, to use it for production of various building materials. However, variable asbestos (free and fixed) content of the waste and admixtures of chromium, nickel and other elements in it prevent from utilisation of asbestos waste at other enterprises and necessitate further hygienic evaluation.     

Cutaneous hazards of the coast

Through recreational and commercial pursuits, more people than ever before are coming in contact with coastal waters containing a variety of bacteria, aquatic flora, and sea creatures potentially harmful to the skin. It is important for dermatology nurses to be aware of some of the more common cutaneous hazards related to the coastal environment as well as the basic treatment of these problems.     

Potential hazards of the co-therapy relationship.

In addition to describing the potential advantages of cotherapy, the authors also discuss the injuriousness of the cotherapy relationship in terms of hazards to patients, spouses and/or significant others, and cotherapists themselves. Some potential remedies from an ongoing treatment and training program are offered, along with the caution that successful cotherapy requires careful thought and restraint on the part of both parties. (8 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Control of biologic hazards

Spontaneous and diepoxybutane (DEB)-induced sister-chromatid exchanges (SCEs) were examined in whole-blood lymphocyte cultures of 3 men and 4 women. A strong increase in mean number of SCEs per cell with increasing DEB concentrations (0, 2, and 4 microM) was observed in cultures of all subjects, but 3 of the donors were clearly more sensitive than the others. The SCE measurements were repeated 2-6 times per donor over a period of 55 months to assess the stability of the individual SCE response. The results showed that SCE induction by DEB was steady in the individuals during the follow-up at each DEB dose, with no significant differences among the repeated experiments. At 4 microM DEB, the DEB-sensitive and -resistant donors could be reliably be differentiated from each other in all trials. As DEB-sensitivity has been suggested to be due to the lack of glutathione S-transferase (GST) T1, the donors were genotyped for the presence of GSTT1 and GSTM1 genes. The 3 individuals found to be DEB-sensitive were all of the GSTT1 null genotype, whereas the 4 DEB-resistant donors were GSTT1 positive, which supported the role of the GSTT1 gene in determining DEB-sensitivity. Three of the DEB-resistant and none of the DEB-sensitive had the GSTM1 null genotype. Thus, the lack of the GSTM1 gene was not associated with the DEB-sensitivity trait. In conclusion, the present findings show that individual SCE responses to treatment of cultured human lymphocytes with DEB can reliably be reproduced in repeated trials. The results confirm that the GSTT1 gene but not the GSTM1 gene is important in determining individual sensitivity to the in vitro genotoxicity of DEB.     

Skin sensitivity of the arm

One hundred and sixty seven operating theatre personnel familiar with the practice of venous cannulation were asked to rank (in increasing order from one to five, corresponding to least to most painful) their opinion of the pain which they considered might accompany venous cannulation of each of five vein sites on the upper limb (dorsum of arm, dorsum of hand, cephalic, ventrum of arm and cubital fossa) which may be selected for this purpose. The skin sensitivity of each of the test sites of each volunteer was then assessed with a test device comprising a Tuohy needle and clamp, which together weighed 75.02 g. Following random application of the device to each of the test sites, the volunteer was asked to rank (in increasing order from one to five, corresponding to least to most painful) the actual pain felt. Analysis of pain expectations showed that there was no significant consensus view as to which site would be most tender. Following application of the test device the tenderness of the five sites was ranked (i) according to frequencies; dorsum of arm < dorsum of hand < cephalic < ventrum of arm < cubital fossa and, (ii) following statistical analysis: dorsum of arm = dorsum of hand = cephalic < ventrum of arm < cubital fossa. There was no correlation between expected and actual skin sensitivities. Knowledge of the different skin sensitivities of the upper limb may be useful when selecting a vein for venepuncture or the insertion of an indwelling venous catheter.     

Anthropogenic sources of radiation hazards

0-/-B-hydroxyethyl/rutoside has been investigated for its effect on laser-induced thrombus formation in rat mesenteric venules and arterioles. The in vitro effect of this agent on platelet adhesion to bovine subendothelial extracellular matrix (ECM) and glass, on spreading and on platelet aggregation induced by ADP, collagen and epinephrine have also been studied. The animal investigations of 0-/-B-hydroxyethyl/rutoside showed an antithrombotic effect in doses between 5 and 50 mg/kg after i.v. injection. This effect was similar for both arterioles and venules damaged. After i.v. injection of minimum effective doses of 0-/-B-hydroxyethyl/rutoside, the antithrombotic effect lasted longer than 6 hrs but less than 12 hrs. In vitro, 0-/-B-hydroxyethyl/rutoside significantly inhibited platelet adhesion to bovine ECM in concentrations of 20 micrograms/ml PRP, and with 30 micrograms/ml the PRP adhesion to glass and spreading were inhibited. Epinephrine and ADP induced aggregation was inhibited in concentrations higher than 30 micrograms/ml PRP.     

The radiological hazards of plutonium

About 1,500 tonnes of plutonium, 1,200 tonnes civilian, are now in world stockpiles, of which 200 tonnes have been separated from spent fuel in reprocessing plants. This will rise to 300 tonnes by the year 2000. Such reactor-grade plutonium contains a higher proportion of isotopes other than Pu-239, which progressively increases with longer burn-up. These isotopes have an increased risk of causing cancer, particularly if inhaled. Possible cancer rates from scattering of such plutonium in a city centre (e.g. by terrorist activity) are considered, and the implications of these calculations for the wisdom of continued reprocessing of spent nuclear reactor fuel are discussed.     

分卷平整机组的改进

介绍了分卷平整机组生产中出现的问题,针对存在的问题进行了改进,取得了较好的效果。     

Skin problems in the traveler

Skin lesions are common in travelers and include a mix of mundane dermatologic problems and rare diseases acquired only in remote or tropical regions. The morphology, distribution, and progression of the lesions are useful in assessing possible causes. Early in the evaluation it is important to determine whether the patient might have a process that is rapidly progressive, treatable, or transmissible. In addition to routine laboratory studies, biopsy and serologic tests are often necessary to confirm a specific diagnosis.     

平整机组湿平整吹风系统改造

鞍钢冷轧薄板厂平整机组钢板存在边部平整液残留缺陷,为此,自行设计、制造了相关设备,对湿平整吹风系统进行了改造,取得了良好的效果,平整后产品的合格率由75%提高到90%.     

Optical radiation hazards of welding arcs

Welding, a widely used industrial process, is one of the most intense artificial sources of optical radiation. Each type of welding process emits a different spectrum and intensity of optical radiation. For most processes, ultraviolet and visible radiation are the main components of the emission. Such factors as arc current, shielding gas, and base metal influence the emission spectrum. Adverse effects are confined to the skin and eyes, with welders suffering from a higher proportion of optical radiation associated eye conditions than do non-welders. Erythema is a common skin condition among welders, but conditions like skin cancer are rare. An evaluation of optical radiation from welding consists of determining an effective irradiance and a maximum permissible exposure duration, which can be very short (from seconds to minutes). Control measures include the use of screens to localize the hazards, and the use of personal protective equipment, such as protective clothing, safety spectacles, and welding helmets. Recent studies indicate that optical radiation can infiltrate into helmets and workers may be exposed to excessive levels. Overall, further investigation into adverse health effects and safety equipment design is warranted.     

Refractive hazards of intraoperative retinal photocoagulation

Coaggregations between bacterial species have been widely studied in vitro but not in the mouth. A new in vivo assay was used to measure the rate and composition of indigenous plaque formation onto bovine enamel chips covered with a continuous layer of bacteria. Chips were covered with Streptococcus oralis ATCC 10557, which coaggregated with many oral species, or Streptococcus gordonii S7, which did not coaggregate with these oral species, and placed in the mouth for 4 and 24 h. There were no differences in the number of most indigenous bacterial species isolated from the two streptococcal surfaces. However, the number of Actinomyces viscosus as a proportion of total Actinomyces spp. was significantly different on the two surfaces at 24 h. With the exception of Actinomyces naeslundii and A. viscosus removed from the S7 surface, all indigenous species increased significantly in number from 4 to 24 h, irrespective of the streptococcal surface. This study demonstrated that interbacterial coaggregation had only a limited effect on in vivo plaque development. Thus suggesting that environmental factors, growth or other adherence phenomena are dominant in in vivo plaque formation.