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Equipment and methods for measuring ultrasonic noise at workplaces
Jan Radosz, Tomasz Krukowicz
Ultrasonic noise is a harmful factor in the work environment. The assessment of exposure to ultrasonic noise is based on the spectral analysis of one-third octave bands with center frequencies in the 10 - 40 kHz range. This paper presents a method of measuring the noise, an analysis of the factors affecting the determined sound pressure levels, a review of the apparatus for measuring ultrasonic noise and the possibility of its calibration. This article attempts to standardize the methods of measuring and evaluating ultrasonic sound, which is extremely important due to the lack of current standards for risk assessment.
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Method of evaluating machines emitting nonlaser optical radiation
Andrzej Pawlak
This article discusses a method of evaluating machines emitting optical radiation, which involves measuring parameters of ultraviolet, visible or infrared light listed in standards PN-EN 12198 Part 1 and 2. The category of radiation of specific machines is determined on the basis of the results of those measurements. The value of emission categories is the basis for assessing the risk of employees exposed to radiation and for determining the types of measures reducing the emission of radiation. This article characterizes those types of radiation and gives examples of machines with the relevant technological processes. The method of evaluating emission categories is shown in three sample machines that emit ultraviolet, visible and infrared radiation.
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Integrated Testing Strategies for toxicity testing of nanotechnology products
Lidia Zapór
The development of nanotechnology is expected to result in the launching of a number of new nanostructured products, which will have to be classified in terms of hazards. The Integrated Testing Strategy (ITS) can be used to assess the chemical safety of nanomaterials. This article discusses the principles of ITS and of alternative methods for toxicity testing; it also contains information about REACH recommendations on information requirements and chemical safety. There is an example of how ITS is used to test the toxicity of nanoparticles.
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Hexachlorocyclopentadiene. Documentation
Jadwiga A. Szymańska, Barbara Frydrych
Hexachlorocyclopentadiene (HCCP) is an oily liquid with a light yellow color and a pungent odor. This compound is used primarily as an intermediate for the manufacture of various dyes, resins, pharmaceuticals, flame retardants, insecti-cides, and polyesters. It is also used to produce ketones, acids, esters, fluorocarbons, and shock-proof plastics.
HCCP is absorbed into the body through the skin, respiratory and digestive tract as well as after intravenous administration. Determination of tissue HCCP deployment showed that the highest concentrations were related to liver and kidney, regardless of route of administration. The main routes of excretion are the urine and feces.
HCCP is irritating to mucous membranes of the eyes and upper respiratory tract and skin. Acute toxicity studies in animals have shown a large span media in the values of the lethal dose. From the available data, it can be concluded that HCCP is harmful after acute oral exposure, toxic after acute dermal exposure and very toxic after inhalatory exposure.
Repeated exposure of animals of different species to HCCP administered by various routes resulted in increased mortality observed in the exposed groups and the occurrence of a number of clinical signs and histopathological changes.The results of tests carried out in vitro and in vivo indicate that the HCCP is not mutagenic or genotoxic. Moreover, because of the results obtained in experiments on the carcinogenicity, HCCP is not regarded as a substance with carcinogenic activity.
The MAC (TWA) value for HCCP was calculated on the basis of NOAEL value 1.7 mg/m3 obtained as a result of an inhalation experiment. The recommended 8-hour TWA is 0.1 mg/m³.
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Acrylic acid. Documentation
Jadwiga A. Szymańska, Barbara Frydrych
Acrylic acid (2-propenoic acid) is a colorless, flam-mable, volatile liquid with an unpleasant odor, which forms obnoxious fumes. It has a corrosive effect and is very easy to polymerize. World production of acrylic acid is around 2.4 million tonnes per year. This compound is used as an intermediate in the synthesis of acrylates, acrylic polymer.
Acrylic acid can be absorbed by inhalation, and through dermal and intragastric routes. There is no information in the available literature on the toxic effects of acrylic acid to humans. In some cases, there were skin burns and severe irritation to the respiratory system in poisoned employees.
Occupational exposure of humans to acrylic acid is possible during its production and use, especially in the chemical industry. In the Polish industry , work-ers' exposure to acrylic acid concentration in excess of the admissible limit value, or the value of the threshold limit value-time weighted average (TLV-TWA) of 20 mg/m³ and the short term exposure limit (STEL) of 50 mg/m³ was not detected in 2010.
Acrylic acid is classified as a compound with low or moderate acute toxicity. In rats exposed to acrylic acid by inhalation at a concentration of 75 mg/m³ for 13 weeks, there were no changes related to the toxicity of the compound (NOAEL). With an increase in the concentration of acrylic acid up to 225 mg/m³, it showed adverse effects to the upper airways due to irritant action.
Genotoxicity of acrylic acid in vitro studies was observed in mouse lymphoid cells and Chinese hamster ovary. Experiments performed in vivo showed no genotoxic activity of acrylic acid. ACGIH included acrylic acid in the A4 group and IARC in group 3, compounds not classified as carcinogenic to humans.
In the literature, no information has been found on the mechanism of toxicity or toxic effects of acrylic acid with other compounds.
The results of 13-week inhalation experiments in rats, in which no toxic effects were observed after exposure to acrylic acid at the concentration of 75 mg/m³ (NOAEL) were the basis for determining the value of the TWA. Following the adoption of appropriate uncertainty factors, we proposed reduction in force in Poland of the MAC (TWA) value of 20 to 10 mg/m³, and the short term exposure limit (STEL) of 50 to 29.5 mg/m³. We also proposed to leave (not to change) the marking with the letters "Sc" - the substance is absorbed through the skin and "C" - corrosive.
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4,4’-Thiobis(6-tert-butyl-3-methylphenol) – inhalable fraction. Documentation
Katarzyna Konieczko, Sławomir Czerczak
4,4’-Thiobis(6-tert-butyl-3-methylphenol) is a white to light gray or tan powder with a slightly aromatic odor. It is insoluble in water (0.08%). Its volatility is low: 6 • 10-7 mm Hg (70 °C). TBBC is used as antioxidant in polyethylenes, polypropylenes, vinyl polymers and synthetic rubbers. There is no harmonized classification and labeling of TBBC legally established in the EU. Some manufactures classify TBBC as irritant and skin sensitizer, although human data are ambiguous and animal data indicate a weak irritation or sensitization potential of this compound. The critical effect of a long-term exposure to TBBC is hepatotoxicity and this effect was considered in setting exposure limits. A NOAEL value is 20 mg/kg bw based on a 2-year diet experiment on rats. After using uncertainty factors, a MAC (TWA) value of 35 mg/m³ was calculated. Because there is an exposure to TBBC dust in the working environment, a MAC (TWA) value of 10 mg/m³ for inhalable fraction of TBBC as for other non-toxic industrial dusts was suggested. There are no grounds for establishing STEL or BEI values.
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Respirable crystalline silica: quartz and cristobalite. Determination in the workplace with FT-IR spectrometry: KBr disc method
Aleksandra Maciejewska
This method is based on measuring absorption bands in the infrared range for respirable quartz and respirable cristobalite. Samples are ashed and analysed after the preparation of a standard disc with KBr. The working range of the analytical method is from 10 to 400 μg (0.015 – 0.5 mg/m³ for a 700-L air sample).
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