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Hydroxypropyl acrylate –determination method
Małgorzata Kucharska, Wiktor Wesołowski
The method is based on the adsorption of hydroxypropyl acrylate on charcol, desorption with dichloromethane and gas chromatographic (GC MSD) analysis of the resulting solution.
The determination limit of the method is 0.2 mg/m³.
2-Ethylhexylnitrate –determination method
Krystyna Wróblewska-Jakubowska
The method is based on the adsorption of vapours of 2-ethylhexylnitrate on silica gel, desorption with methanol and its determination in the obtained solution by gas chromatography with flame ionization detection (GC-FID).
The determination limit of the method is 0.35 mg/m³.
1-Bromopropane and 2-bromopropane –determination method
Barbara Romanowicz
The method is based on the adsorption of 1-bromopropane and 2-bromopropane vapours on activated charcoal. Samples are desorbed with 1 ml of carbon disulfide and analyzed by gas chromatography with a flame ionization detector (GC-FID).
The determination limit of the method is 1.0 mg/m³ for each of isomer.
4-Chlorofenol –determination method
Sławomir Brzeźnicki
Air samples are collected by drawing a known volume of air through sorbent tubes containing two sections of silica gel 20/40 or 35/70 mesh. Samples are extracted for 30 min in an ultrasonic bath with 1 ml of acetonitrile. The obtained extracts are diluted with 2 ml of deionized water and analyzed by high performance liquid chro-matography using ultraviolet detection.
The working range of the analytical method is from 0.3 to 20 μg/ml (0.025 – 1.5 mg/m³ for 40 l air sample).
2-(Dibutylamino)ethanol –determination method
Krystyna Wróblewska-Jakubowska
The method is based on the adsorption of 2-(dibutylamino)ethanol on Tenax TA, desorption with methanol and analysis of the resulting solution by gas chromatography with flame ionization detection (GC-FID.
The determination limit of the method is 2 mg/m³.
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Barium and its soluble compounds. Documentation
Andrzej Sapota, Małgorzata Skrzypińska-Gawrysiak
Barium is a metallic, alkaline, chemically reactive element found in soil. Its salts – chloride, nitrate, acetate and carbonate – belong to soluble barium compounds. Barium salts are classified as harmful compounds. Barium and its compounds have broad industrial application (e.g. in chemical, glass-making, ceramic and electrotechnical industries); they are also used as fluxes in welding electrodes.
Occupational exposure to barium and its soluble compounds (dust, smoke) takes place mainly in steel, glass-making, metallurgical and mining industries.
The minimal oral, lethal dose for a human is about 10 mg/kg for barium chloride and about 60 mg/kg for barium carbonate. Barium carbonate in a dose of 20 mg/kg causes muscular weakness, paraesthesia and flaccid paralysis. Barium: carbonate, chloride, nitrate and acetate are compounds most frequently causing acute intoxication.
Acute gastrointestinal disorders, weakening of deep reflex and decreased muscle tone as well as reduction of muscle strength and flaccid paralysis are usually observed in the clinical picture of barium compound intoxication. Death is usually the result of respiratory arrest (respiratory muscles paralysis) and circulatory arrest. These symptoms are accompanied by a decrease in the concentration of serum potassium and ventricular tachycardia which then transform into ventricular fibrillation. Acute renal failure, rhabdomyolysis, dysphagia and arterial hypertension may also result from acute intoxication with barium compounds.
DL50 values for soluble barium compounds are within the range of 118 – 800 mg/kg.
Barium compounds demonstrate weak irritating action and no allergy reaction.
The subchronic and chronic investigations carried out on different animal species have mainly demonstrated a decrease in body mass and the mass of some organs, and a renal defect which intensified depending on the applied doses.
Barium and its soluble compounds do not demonstrate mutagenic, genotoxic or carcinogenic activity. There is no sufficient evidence on the effect of barium and its compounds on reproduction.
Barium and its soluble compounds have a toxic effect on the cardiovascular system causing mainly hypertension and arrhythmia. Such effects have been observed both in humans and in animals. Furthermore, on the basis of the results of chronic experiments on animals, kidneys have been demonstrated to be the critical organ.
To calculate MAC values, the results of Zschiesche et al. (1992) were accepted. The concentration of 4.4 mg Ba/m³ was assumed for the NOAEL value.
The following uncertainty factors were accepted in calculating the MAC value: A=2, individual sensitivity differences, B=2, resulting from short- to long-term investigations, C=2, a modifying coefficient associated with the lack of data concerning absorption efficiency in the respiratory tract. Thus, the calculated MAC value is 0.55 mg/m³.
On the basis of the presented calculations we suggest the concentration of 0.5 mg Ba/m³ to be accepted as the MAC value for barium and its soluble compounds. The suggested MAC value should protect workers against any effects of the systemic action of barium and it should protect against changes in the cardiovascular system. The MAC value, which has been valid so far in Poland is also 0.5 mg/m³ but it concerns barium and all its inorganic compounds.
There are no grounds for accepting STEL values for barium. Due to the lack of data, the determination of BEI values is not suggested, either.
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2-(2-Butoxyethoxy)ethanol. Documentation
Andrzej Starek
2-(2-Butoxyethoxy)ethanol (BEE) is a liquid with low vapor pressure. It is miscible with water and organic solvents. BEE is used as a solvent in paints, dyes, inks, detergents and cleaners and also as an intermediate and as a component of fire extinguisher foam and hydraulic fluids.
There are no data available on toxicity of BEE in humans.
Acute toxicity of this chemical is low in rats and rabbits. It is not irritating to the skin, but irritates the eye. Undiluted BEE is not sensitizing in guinea pigs, but positive skin reaction to this compound in single humans has been observed. The systemic toxicity of BEE is low. The critical effects are local irritation of the lung, disturbance renal function, and intravascular hemolysis. BEE did not show genotoxicity in many tests and also embryotoxicity, fetotoxicity, and teratogenicity. There are no data available on carcinogenicity.
In setting exposure limits, the results of a subchronic intragastric exposure in rats were considered. Based on the LOAEL value (290 mg/kg/day) and the relevant uncertainty factors, a MAC (TWA) value was calculated at 63.4 mg/m³. The MAC (TWA) and MAC (STEL) values of 67 mg/m³ and 100 mg/m³, respectively were suggested. These values are consistent with project of European Commission Directions.
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Chloroacetyl chloride. Documentation
Hanna Grunt, Sławomir Czerczak
Chloroacetyl chloride is a colorless or yellowish liquid with a pungent odor. This substance has been used as an intermediate in the production of chloroacetophenone, as a lacrimator, in pharmaceutics, in the manufacture of diazepam, adrenaline and chloracetamid herbicides.
Chloroacetyl chloride is harmful by oral route of administration (LD50 for rats is 208 mg/kg, for mice 220 mg/kg ) and low toxic by inhalation route (LC50 for rats is 4620 mg/m³/4h, LC50 for mice is 6006 mg/m³/2h). The cutaneous LD50 for rabbits is 662 mg/kg.
The acute toxicity test proves an intense irritant effect of chloroacetyl chloride on the eyes, skin and mucous membranes of the upper respiratory tract of animals. Prolonged exposure causes respiratory failure and collapse. Exposure at a high concentration of vapor phases in human results in erythema, chemical burns, lacrimation, painful burning sensation of the eyes, dyspnea, cyanosis, cough, stomach and intestinal disorders. Prolonged contact with the skin may cause similar effects and also skin damage, which may indicate a caustic effect. Prolonged inhalation causes irritation of the eyes, skin and the upper respiratory tract.
Based on the LOAEL value obtained from experiments on rats and mice (2.31 mg/m³) a MAC-TWA value of 0.2 mg/m³ was established as the ceiling value for chloroacetyl chloride. Because of the irritant effect of this compound, a MAC-STEL value of 0.6 mg/m³ was suggested. These values should prevent irritation of the eyes, skin and the respiratory tract.
Because chloroacetyl chloride has been shown to penetrate the skin, an additional determination with the letters “Sk” has been suggested. Moreover irritant “I” notation has been recommended.
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Methyl chloroacetate. Documentation
Małgorzata Kupczewska-Dobecka
Methyl chloroacetate is a flammable, colorless liquid with a sweet, pungent odor. It is used as a solvent and an intermediate for organic synthesis. The toxicity ot this compound is high. For rats exposed once for 4 hours, the LC50 was about 1350 mg/m³. The substance affects breathing, produces eye irritation, corneal clouding, cyanosis, and non-specific symptoms of intoxication. It is irritant and corrosive to all tissues. After either a single or repeated inhalation exposure, the main effect is local irritation. Methyl chloroacetate vapour led to delayed eye irritation in exposed workers.
Groups of five male and five female rats were exposed to methyl chloroacetate vapour concentrations of 44; 146, 443 mg/m³ for 6 hours daily, 5 days per week, for 28 days. In addition to irritation, effects on breathing and coordination were seen in animals from the 443 mg/m³ group. In the animals from the 146 mg/m³ group, substance-specific irritation of the mucous membranes was observed. The concentration of 44 mg/m³ is given as the no effect level.
Based on these animal data the Expert Group for Chemical Agents established an 8-hour TWA value of 5 mg/m³, and a STEL value of 10 mg/m³. The notations: “I” (irritating substance) and “Sk” (substance absorbed through the skin) were proposed.
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n-Hexane. Documentation
Marek Jakubowski
n-Hexane is a colorless liquid, readily volatile with a boiling point of 69 °C. Technical grade hexane is a mixture of n-hexane and isomers of methylpentane and heptane. n-Hexane is commonly used as a solvent component of paints and thinners and especially glues. Ii is also present in gasoline. Occupational exposure to n-hexane may occur in rubber, chemical, pharmaceutical and shoe industries.
n-Hexane is readily absorbed by all routes of exposure. In industrial settings, absorption takes place primarily via respiration. Retention rate of 28 – 34% has been reported. The rate of absorption of liquid hexane through the skin is 0.31 mg/cm²/h.
Metabolism of n-hexane is important from the point of view of toxic effects. The metabolite, 2,5-hexanodion (2,5-HD), is responsible for toxic effects on peripheral nervous system inducing polyneuropathy. 2,5-HD can be derived in vivo from n-hexane via 2-hexanol, to either 2,5-hexanediol or methyl butyl ketone, and then to 5-hydroxy-2-hexanone, the last being interconvertible with 2,5-HD. n-Hexane is eliminated unchanged in exhaled air. After termination of exposure concentration in exhaled air it declines rapidly after cessation of exposure with apparent half-lives of 5 to 10 minutes and 100 minutes. Urinary excretion is negligible. The major elimination pathway is metabolism. The major metabolite is 2,5-hexanodione, which is eliminated with an apparent half-life of 13 – 14 hours and therefore, has a potential for accumulation over the workweek.
Occupational exposure shows that n-hexane is toxic to the peripheral nervous system. Cases of sensorimotor to amyotrophic polyneuropathy have been observed among workers exposed to n-hexane in concentrations of up to 9000 mg/m3 for 48 hours or longer per week. Some of the affected individuals had exposure below 1800 mg/m³. In spite of numerous investigations in the industrial setting the dose-effect and dose-response relationships have not been established because workers were usually exposed to a mixture of solvents. The toxicity of n-hexane to induce polyneuropathy after repeated exposures was further confirmed by animal experiments. In rats, degeneration of axons in peripheral nerves occurred as a result of exposure to n-hexane in concentration of 1760 mg/m³ (9 weeks, 7 days/week, 22 h/day).
The proposed occupational exposure limit (OEL-TWA) of 100 mg/m³ is based on the NOAEL (204 mg/m³) value derived from long-term (6.5 years) observation of the group of 14 persons exposed to a mixture of n-hexane and acetone and the uncertainty factor of 2.
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2,2’-Iminodiethanol. Documentation
Krystyna Sitarek
2,2’-Iminodiethanol (DEA) is used as an intermediate in the production of surfactants, soaps, and as a dispersing agent for agricultural chemicals. At room temperature it is a solid or a liquid. The oral LD50 for rats is in the range of 1400 – 3400 mg/kg b.w. DEA is absorbed through the skin; it is moderately irritating to the eye and skin. This substance, administered subchronically, orally or dermally to rats, induced changes in the liver and kidneys.
DEA is not a mutagenic, carcinogenic and teratogenic agent. Its carcinogenicity to humans is not classifiable (Group 3 – IARC). DEA is incorporated into membrane phospholipids. It is excreted unchanged in urine.
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2-Isopropoxyethanol. Documentation
Katarzyna Konieczko, Sławomir Czerczak
2-Isopropoxyethanol (IPE) is a monoalkyl ether of ethylene glycol. It is a colorless liquid with a mild etheral odour and bitter taste. IPE is used as a solvent for cellulose esters, lacqers, resins, dyes and printing inks.
2-Isopropoxyethanol is on the list of dangerous substances – it is classified as harmful by inhalation and skin contact, and irritating to eyes.
The critical effect of IPE is its haemolytic activity. The 8-h TWA value was calculated on the basis of the results of a 4-week inhalation study on rats – in this study IPE concetration of 128 mg/m3 was the NOAEL for the haemolytic effect – and uncertainty factors. A similar value of MAC (TWA) was calculated on a LOAEL of 106 mg/m³ from the results of a 26-week inhalation study on rats. It is important that the uncertainty factor connected with species differences between humans and rats (B) was only 1 because the rat is more sensitive to the haemolytic effect than man. The 8-h TWA value of 20 mg/m³ was established and a skin notation was assigned. No STEL was established.
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2-(2-Methoxyethoxy)etanol. Documentation
Andrzej Starek
2-(2-Methoxyethoxy)ethanol (DEGME) is a colorless liquid with pleasant odour.It is used in variety of industrial applications including the manufacture of plastics, as bases for inks, dyes and cleaners and as deicing agent, and also as diluent for hydraulic brake fluid, and in water-base paints.
There are no data available on toxicity of DEGME in humans.
In rats treated with this chemical the decrease of body weight and relative organ weights, and also elevated indicator enzyme activities in serum and intravascular hemolysis were observed. There are no available literature data on DEGME genotoxic and carcinogenic activities. This compound exerts embryotoxic, fetotoxic and teratogenic effects.
Based on the LOAEL value (1050 mg/m³) obtained in a subchronic experiment in rats and the relevant uncertainty factors, a MAC (TWA) value was calculated at 133 mg/m³. In accordance with project of European Commission Directions the MAC (TWA) value at 50 mg/m³ was suggested. Because DEGME has been shown to penetrate the skin in amounts sufficient to induce systemic toxicity and exerts reproductive toxicity, a skin (“Sk”) and fetotoxic (“Ft”) notations are considered appropriate. No MAC (STEL) value has been established.
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2-Methylnaphthalene. Documentation
Jolanta Skowroń
2-Methylnaphthalene (2-MN) is a white solid that evaporates easily. It is also called mothballs. 2-MN with 1-methyl- naphthalene are used to make other chemicals such as dyes, resins, leather tanning agents, and insecticides. It is also a component of many commonly used commercial solvent mixtures like Solvesso 200 and fossil fuels such as petroleum and coal. Burning tobacco or wood produces 2-MN. Pure 2-methylnaphthalene is used in vitamin K production. Because of its common use, probably a lot of people in Poland are exposed to this substance.
Exposure to this crystalline substance may occur in its production or use as a chemical intermediate in organic syntheses. 2-Methylnaphthalene can enter the body by inhalation, through the skin and by ingestion. The substance is very quickly eliminated from the body with the urine and some in the stool. 2-MN is irritating to the eyes, the skin and mucous membranes. No information has been located that documents acute and long-term exposure in humans.
2-Methylnaphthalene is harmful for laboratory animals by oral route. The LD50 for rats is 1630 mg/kg. There is variability in the manifestations and degree of substance toxicity between animal species, sex, and route of exposure. Mice are the most sensitive to the pulmonary toxicity of 2-methylnaphthalene, followed by hamsters and rats. The main effects of 2-MN on animals are irritation for the respiratory tract and neurotoxicity.
The Expert Group has established 25 mg/m³ as the maximum exposure limit (MAC) for 2-methylnaphthalene based on the experiment on mice fed diets containing 2-MN for 81 weeks. The dose of 87.5 mg/kg was established as the lowest-observed-adverse-effect level (LOAEL), which was then re-calculated for humans. Due to the irritant effect, the MAC-STEL value was established at the level of 50 mg/m³. The Group has suggested an additional determination with letters “I” (irritation) and “Sk” (skin).
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The activity of the Interdepartmental Commission for Maximum Admissible Concentrations and Intensities for Agents Harmful to Health in the Working Environment in 2005
Jolanta Skowroń
In 2005 the Commission met at three sessions, in which 27 documentations for recommended exposure limits of chemical substances and a verification of the MAC for dusts containing asbestos were discussed. Moreover the Commission discussed:
– a proposal for establishing MAC values for anaesthetic gases
– a proposal for a revision of the ordinance on official certification of automotive vehicles in the aspect of workers’ health and safety.
The Commission suggested to the Minister of Economy and Labour the following changes in the list of MAC values:
– putting 8 new chemical substances on the list of MAC values: (2-butoxyethoxy)ethanol, allyl chloride, desflurane, tert-butyl methyl ether, 1,3-ethylenethiourea, isoflurane, 2-(2-methoxyethoxy)ethanol, sevoflurane
– changing MAC values for 16 chemical substances: 2-aminoethanol, antymony and inorganic compounds, as Sb; arsine, barium and soluble compounds, as Ba; chlorine, chlorobenzene, chloromethane, cyanamide, fluorine, as F–; iodomethane, xylene – mixed isomers (1,2-, 1,3-, 1,4-), 4-methylpent-3-en-2-one, morpholine, nicotine, tetraethyl silicate, toluene
– changing MAC values for dusts containing asbestos.
Four issues of the “Principles and Methods of Assessing the Working Environment” quarterly were published in 2005. Issue 1(43) contained 6 methods of assessing the working environment and 7 documentations for recommended exposure limits along with analytical procedures, recommendations in respect to pre-employment and periodic medical examinations and contraindications to exposure. Issues 2(44) and 3(45) contained 17 documentations. In issue 4(46) there were 5 methods of assessing the working environment, and 5 documentations.
Three sessions of the Commission are planned for 2006. MAC values for 25 chemical substances and MAI for ionizing and non-ionizing radiation will be discussed at those meetings.
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