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PubMedDate not supplied

[Hygienic assessment of components of smoking fume].

Analyzing the chemical composition of smoking fume has indicated that maximum allowable concentrations (MACs) have been established for 50 of 400 well-known compounds, working area MACs were standardized for 42 of the 50 compounds, the maximum single and daily average concentrations were standardized for 34 and 30 compounds, respectively. All standards were established for 25 compounds. Despite the fact that there a large list of MACs, it is difficult to calculate the objective hygienic risk of smoking smoke since 32 compounds are contained in traces. Hygienic assessment of fume discharges from the smoking chamber by taking into account their mass and MACs demonstrated that phenols, carbonyl compounds, acids, and benz(a)pyrene which should be used to work out the unified hygienic standard are of the greatest importance.

Acetic Acid↗
PubMed1991

[Data for substantiation of MPEL of 1,2,4-triazole in the workplace air].

1,2,4-Triazole belongs to the 3-d degree moderately dangerous compounds, according to the parameters of acute intragastric toxicity (LD50). Single and repeated applications of the substance on the skin of rats does not lead to local irritating or skin-resorptive effects. In the native state the substance produces moderate irritating effects on the eye mucosa of rabbits. It produces a moderately manifest cumulative effect of the functional character (Kcum greater than 5). 1,2,4-Triazole belongs to the 2-nd degree of danger according to LC50. The threshold of acute inhalational exposure (Li(mac)) 226.6 mg/m3, the threshold of chronic inhalational exposure (Lim(ch)), 19.8 mg/m3. The substance does not have mutagenic and embryotropic properties. 5 mg/m3 is recommended as the maximum allowable concentration for 1,2,4-triazole in the air of the working area.

Air Pollutants, Occupational↗
PubMedDate not supplied

[Occupational progressive systemic sclerodermia caused by a quartz-containing scouring agent].

We present the case of a 65-year-old woman with progressive systemic sclerosis. For 14 years, she had been occupationally exposed to scouring powder containing crystalline silica. In the skin of the finger of the patient, silica crystals were detected by polarizing microscopy. By means of a special dust measurement at the former working places where scouring powder was used, a silica exposition could be found exceeding the maximum allowable concentrations. Legal recognition of an occupational disease could be achieved in a special procedure by the top expert commission for occupational diseases.

Female↗
PubMed1993

[Assessment of hazardous chemical substances entering water reservoirs of public and domestic water supply].

The paper gives the evaluation of chemical hazards according to indexes of digestive tract functional state when harmful chemicals enter human body with drinking water and also according to such specific effects as genital, embryotoxic, carcinogenic, allergic and teratogenic ones. The author offers an express method of developing MAC (maximum allowable concentrations) of harmful substances based on reducing the time of chronic experiments with due account of group regulation.

Animals↗
PubMed1993

Occupational diseases developed as a result of severely injured nervous system: acute and chronic neurotic effects.

Some results of multiple epidemiological, clinical, electroneurophysiological, and psychological studies that reveal different types of neurotoxicoses are presented in this work. Under conditions of present-day industry, when a worker is exposed to concentrations close to but below the maximum allowable concentrations, or MAC values, of toxic substances, acute neurotoxicoses rarely develop, occurring perhaps only in catastrophies. Acute intoxications may be accompanied by mass hysteria, which impedes etiological diagnosis and prognosis. Vegetative polyneuropathy is the most common type of chronic intoxication where central vegetative disorders sometimes precede the peripheral ones. Clear forms of intoxication caused by neurotrophic poisons show stable torpid development during subsequent phases of a disease despite the absence of contact with the toxicant.

Carbon Disulfide↗
PubMed1988

The effects of n-butanol vapour on respiratory rate and tidal volume.

Exposure to n-butanol vapour gave rise to a sensory irritation response which was measured by the reflexively induced decrease in respiratory rate in mice according to the American standard method (E981-84). The response reached maximum within the 1st min of exposure. In this period the expected threshold response (RD-0) and the concentration expected to depress the respiratory rate by 50% (RD-50) were extrapolated to be 233 ppm and 11,696 ppm, respectively. The response followed the dynamics of a bimolecular reaction between butanol and the sensory irritant receptor. For concentrations below 3000 ppm, the response faded due to desensitization. However, concentrations above 3000 ppm gave rise to a new decrease in respiratory rate due to activation of lung receptors. Two types of lung receptors, probably J-receptors and stretch receptors, were involved. The sensory irritation response measured by the standard method gave a threshold response which was comparable to that found by electrophysiological experiments in rats. The irritation response in man as well as the maximum allowable concentration in the working environment were adequately predicted from the sensory irritation response in mice.

1-Butanol↗
PubMedDate not supplied

Formation of phosgene during welding activities in an atmosphere containing chlorinated hydrocarbons.

The formation of phosgene During welding activities in an atmosphere containing chlorinated hydrocarbons was investigated. Four different chlorinated hydrocarbons were studied under laboratory conditions. Results are presented as time-averaged phosgene concentration in a total volume of 250 L of air being purged through a 52-L reaction vessel during 20 min. It was found that the formation of phosgene was in the order dichloromethane < Freon-22 < carbon tetrachloride << trichoroethylene. Local concentrations may be higher depending on dispersion phenomena. The interpretation in terms of occupational health was rather difficult because of the interaction with smoke particles and because of possible nonhomogeneous dispersion of phosgene around the workers. In the case of dichloromethane and carbon tetrachloride the short-term maximum allowable concentration (MAC) of phosgene was not attained at the respective MAC values of the chlorinated hydrocarbons themselves. In the case of trichloroethylene and Freon-22, however, the short-term MAC-value of phosgene was attained even when the concentration was still much below the respective MAC-values.

Air Pollutants, Occupational↗
PubMedDate not supplied

[Organic pollution of the Ural river in the area of open water supply of Orenburg].

The water from the Ural river contains about 230 organic chemical substances, including especially hazardous pollutants. The levels of some chemicals are 2 to 13 times higher than their maximum allowable concentrations. It is necessary to use reliable methods for water treatment at waterworks to lower the levels of drinking water pollutants.

Hazardous Substances↗
PubMed1979

[Health effects of trichloroethylene in human subjects (author's transl)].

Trichloroethylene has been widely used for the removal of grease in dry cleaning, plate and painting industries, in which approximately 280 thousand workers contact trichloroethylene, for example, in the United States, resulting in acute and chronic poisonings. Based on 203 papers mainly on trichloroethylene toxicity on human beings, the present review covers acute toxicity, chronic toxicity, carcinogenicity, factors modifying toxicity, metabolism, dose-response relationships and maximum allowable concentration of this chemical. 1 figure and 12 tables.

Acute Disease↗
PubMed1975

[Experimental data on hygienic norms for antibiotics of the tetracycline group].

Toxicity of tetracyclines was studied experimentally on different species of laboratory animals. It was shown that tetracycline, oxytetracycline and chlortetracycline were close by their chemical structure and physico-chemical properties, as well as by the main toxicity parameters, i.e. acute toxicity, cumulative activity, skin-irritating and sensitizing effect. Under the conditions of subacute experiments the above 3 antibiotics induced evenly pronounced one direction changes in animals. The data obtained during the experiments provided recommendation of the level of 0.1 mg/m3 as the maximum allowable concentration (MAC) of oxytetracycline and chlortetracycline, i.e. the same level as the previously recommended for tetracycline.

Administration, Oral↗
PubMed1982

[Hygienic evaluation of the content of heavy metals (lead and copper) in cosmetic products].

Heavy metals /lead and copper/ content was studied in various cosmetic articles: creams and cleansing milk, shampoos, hair dyes, eye shadows, rouge, lipsticks, powders, fond de teint, tooth pastes. The method flame atom-absorption spectrometry with chelation and extraction was used for their determination. The subacute dermal toxicity on albino rats was studied with working doses: lead--1,10 and 100 mg/kg, and copper--5,50 and 500 mg/kg. The content of lead and copper was established to be low in the majority of the cosmetic articles studied /lead--to 2.08 mg/kg, copper--to 6,28 mg/kg/and only in some of the articles of decorative cosmetic, it is considerably higher /lead--to 41,1 mg/kg, copper--to 138,6 mg/kg. That is due to the inadequate purification of the initial raw materials or to the presence of copper-containing dyes in the composition of the respective cosmetic article. As a result from the toxicological and pathoanatomical studies the small doses /lead 1 mg/kg and copper 5 mg/kg are defined as ineffective, and the high doses--with a light biological effect. The maximum allowable concentration of lead is proposed to be--10 mg/kg, and copper--50 mg/kg as side /technical/ pollutants in the production of cosmetic articles.

Animals↗
PubMed2005

Adenine nucleotides in snail muscles as one of biomarkers of fluoride toxicity.

The aim of this work was to determine the extent of bioaccumulation of fluorides in tissues of Helix aspersa maxima. The toxicity of fluorides administered orally on the energy balance of the snail's foot was investigated based on measurements of concentrations of adenine nucleotides and their metabolism degradation products. Quantitation of fluoride levels was done in soft tissues (foot, hepatopancreas) and shells of mature snails. Qualitative and quantitative analysis of purine compounds was performed in slices of foot from mature snails. Fluoride concentrations in pulverized shells were measured using an ion-selective electrode. Gas chromatography was used to determine fluoride concentrations in soft tissues (hepatopancreas and foot). Purines were measured in foot muscle slices with high-performance liquid chromatography (HPLC). Fluoride levels in soft tissues of the snail cannot serve as an indicator for biomonitoring purposes as no significant accumulation was observed during exposure to maximum allowable concentrations of fluoride in drinking water. Contrary to this, levels of fluoride in the shell rose significantly with this concentration of fluoride in drinking water. The effect of fluorides on energy metabolism of foot muscle was evidenced by elevated AMP levels, increased adenine nucleotide pool and reduced conversion of ADP to ATP. Exposure to rising F(-) concentrations was accompanied by decreasing values of the adenylate energy charge AEC. Determination of AMP or AEC in foot muscle of exposed snails seems to be a useful indicator of fluoride effects on metabolic activity.

Adenine Nucleotides↗
PubMed1995

The development of occupational exposure limits for chemical substances in China.

This paper presents a comprehensive review of the occupational exposure limits (OELs) of chemical substances in China. It provides historical background on the development of OELs in this country, with a complete list of traditionally adopted and newly developed OELs for chemicals in workplaces. The philosophical thoughts, the administrative system, the scientific protocols for setting and amending health standards, with emphasis on making health a basic criterion for setting health standards, strengthening epidemiological studies of the human population, integrating epidemiological and toxicological studies, considering technological and economical feasibilities, and making full use of literature information sources are discussed. Further perspectives with respect to practical issues of maximum allowable concentration and time-weighted average, selection of safety factors, and establishment of biological exposure limits are also considered, with the authors' contributions to a discussion on these topics.

Air Pollutants, Occupational↗
PubMed1981

[Studies on the toxicity of toluene (author's transl)].

Toluene has been used widely as organic industrial solvent separately or together with other solvents. Many workers contact toluene resulting in acute and chronic poisonings. Problems studied include its acute and chronic epidemiology, toxicity on animals and human beings, dose-response relationships, fate in the living body (absorption, distribution, metabolism and excretion), maximum allowable concentration and biological monitoring limit value of this chemical. In this paper many recent reports of toxicity and metabolism of toluene are reviewed.

Adult↗
PubMedDate not supplied

[Organization of the system of control of food contamination with mycotoxins].

Mycotoxins are secondary metabolites of microscopic fungi. They are classified with particularly hazardous contaminants of foods and feeds. It has been demonstrated that they are extremely dangerous for the health of man, widely spread and do considerable economic damage. The authors describe in detail the data as to the level of contamination of different foods with aflatoxins, ochertoxins, citrinin, patulin, trichotecenic mycotoxins, and zearalenone. The principal role in the prevention of human mycotoxicoses is played by the control over food contamination with mycotoxins. An organization program of the control has been developed. The principal feature of the program is the organization of the specialized scientific-practical centers responsible for the collection and summarization of the results of monitoring and for the development of prophylactic measures. The authors provide data on the maximum allowable concentrations of aflatoxins in foods validated in different countries. Review the topics concerned with the assessment of the efficacy of the control over food contamination with mycotoxins.

Aflatoxins↗
PubMed1990

[Experimental substantiation of MPEL of dibenz(a,n)anthracene in atmospheric air].

Overt dependence of lung tumour development on the values of the dose administered was shown in experiments on inbred white rats under intratracheal administration of various doses of dibenz (a, h) anthracene (DBA); minimal-effect dose and maximal no-effect dose of DBA were established in the experiment. A theoretically calculated allowable dose was used to calculate MAC of the chemical under study for the ambient air 5 ng/m3 was recommended as an average 24-hour maximum allowable concentration of DBA in ambient air.

Air Pollutants↗