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At least 19 recordsLinked to original sources
PubMed1982

[Maximum immission concentrations and maximum allowable concentrations and their significance in the evaluation of indoor conditions].

In the work-place environment MAK values (maximum allowable workplace concentrations) haven been fixed as time-integrated averages relatively early in order to avoid adverse health effects to workers exposed to air pollution during their working shift. Similarly, MIK values (maximum immission concentrations have been set up to protect the health of the total population. In contrast to this, there are no limit values for pollutant concentrations in non-working place indoor environments. The problem of applying the MIK and MAK value concept to the non-industrial indoor environment is discussed. In this context, mention is also made of the possibility of an indirect uptake of deposited dust or of a diffusion of gaseous components into foodstuff and of other exposure pathways. The discussion shows that the reference to MIK and MAK values can only lead to a first approximation in the evaluation of a non-industrial indoor situation. Further studies are needed to establish limit values for special indoor air pollutants. In this context, the usefulness of the concept of the so-called BAT value for indoor purposes is discussed (BAT = Biologischer Arbeitsstoff-Toleranzwert). It will be an urgent matter to set up emission standards for building materials, furniture, textiles, paints and other possible emitters in order to protect the population from preventable exposure.

Air Pollutants↗
PubMed1993

Studies on the toxicity and maximum allowable concentration of chloroform.

Chloroform has obvious hepato-, nephro-toxicity and carcinogenicity. In order to get necessary data for recommendation of maximum allowable concentration of chloroform in workplace, a series of studies were carried out. The results showed that exposed workers mainly distributed in the industries of perspex processing, production of refrigerants, drugs and pesticides. The exposure level ranged 4.27-147.91 mg/m3 in 119 air samples collected from 3 representative worksites, with 45.4% air samples below 20 mg/m3. The workers exposed to chloroform at 29.51 mg/m3 had slight liver damage indicated by the higher rates of abnormal serum prealbumin and transferrin levels than those of control workers. The neurobehavioral functions of these workers were also obviously affected, manifested as increases in scores of passive mood states and dose-related negative changes in neurobehavioral testing. The observed effect threshold concentration of subacute inhalation in rats was 592 mg/m3 according to the observation on the biochemical changes in liver tissue and abnormal activities of serum enzymes. Mainly based on the above results, we recommended 20 mg/m3 as the Maximum Allowable Concentration in workplace in China at present.

Adult↗
PubMed2002

Assignment of skin notation for maximum allowable concentration (MAC) list in Poland.

Organic chemicals from the Polish maximum allowable concentration (MAC) list were analyzed for skin notation. It can be concluded that the dermal dose LD50s determined on experimental animals ought to be adopted as the fundamental criterion for providing a substance with the percutaneous absorption notation in the MAC list. All chemicals with LD50s. value below 1,000 mg/kg should be provided with the Sk index in the MAC list. For other chemicals, a skin notation would be considered when repeated human and dermal application tests have shown significant systemic effects following exposure. When information on the characteristics specified above were not available, physicochemical data required to calculate the flow (solubility, octanol/water partition coefficient, molecular weight) were obtained to consider a skin notation.

Absorption↗
PubMed1990

[Calculation of maximum allowable concentration of N-nitrosodimethylamine and N-nitrosodiethylamine based on chronic experiments in mice].

Maximum allowable 24-hour human intakes of NDMA and NDEA, calculated with the use of a log-normal model, a model of logit-transformations and methods of confidence intervals and probability estimations, are 0.15 micrograms/kg and 0.03 micrograms/kg respectively. Maximum allowable concentrations for NDMA and NDEA in water are 5 micrograms/l and 1 microgram/l respectively.

Animals↗
PubMedDate not supplied

[Experimental rationale for the maximum allowable concentrations of organic phosphorus toxic agents in the soil].

Hygienic standardization of soil sarin, soman, and Vx levels established the threshold and subthreshold concentrations of the agents from the general sanitary, translocational, and migratory water and migratory air safety indices. Substantiation of their maximum allowable concentrations (MAC), the limiting safety index is a migratory air index for soman and sarin and a migratory water index for Vx. Soil MACs of sarin, soman, and Vx are 2 x 10(-4), 1 x 10(-4), and 5 x 10(-5) mg/kg, respectively.

Environmental Illness↗
PubMed1998

[Adaptation of the terminology of chemicals included in the list of maximum allowable concentrations in work environment to the principles which meet the requirements of the IUPAC guidelines].

Significant changes in the terminology of chemicals have been introduced into the updated Maximum Allowable Concentrations (MAC) list in line with the recommendations of the Polish Chemical Society's Chemical Terminology Committee, based on the guidelines of the International Union of Pure and Applied Chemistry (IUPAC), and adapted to the specific characteristic of the Polish language. The names formed according to new principles often differ considerably from the names used heretofore, any may be difficult to identify for the user of the list. In order to facilitate the use of the new list, new principles of the formation of chemical names are presented with special emphasis put on the changes introduced. The main principles of the terminology for chemicals classified in individual classes of inorganic and organic chemical compounds are described and illustrated. Cases which, in the authors' opinion may turn out to be particularly difficult for the users of the list are discussed in detail.

Chemical Industry↗
PubMed1997

Studies on the hazardous effects and the maximum allowable concentration of pyrophyllite dust.

UNLABELLED: Pyrophyllite (H2Al2Si4O22) dust (P-dust) is a mixture of silica (10-40%), different proportions of a luminium oxide (Al2O3), and various metal compounds. People with occupations known to be associated with exposure to P-dust include miners, other industrial workers and persons engaged in artistic carving. Currently, little is known about pyrophyllite pneumoconiosis from P-dust. This study was designed to investigate the hazardous effects of P-dust and to suggest a maximum allowable concentration (MAC) of the dust. This study included four parts: (i) Occupational epidemiology survey in 781 workers from 1 pyrophyllite mine (PM) and four pyrophyllite carving mills (PCM), with a registration rate of 98%. (ii) IN VITRO STUDIES: Six groups of rats were exposed to different levels of P-dust; the cytotoxicity of P-dust on rat alveolar macrophages (AM) was investigated by determining the potassium content of AM and the activity levels of lactate dehydrogenase (LDH) in AM culture fluid, (iii) Mineralogical analysis of P-dust: The contents of silica (SiO2), aluminum (Al), ferrum (Fe), nickel (Ni), zinc (Zn) and copper (Cu) in both PM-dust and PCM-dust were determined. (iv) Determination of P-dust MAC: Using the life-talbe method, an investigation of the hygiene standard of P-dust was carried out in 625 workers exposed to either PM-dust or PCM-dust, upon whom routine radiographs were performed. The results suggest that the risk of developing pneumoconiosis from pyrophyllite dust is significantly higher for PM workers than for PCM workers. The prevalence rate of PCM-dust pneumoconiosis is significantly higher in men than in women. The content of SiO2 and Al2O3 in the mixture of P-dust is the most important factor in the etiology of pyrophyllitosis. Depending on the different P-dust MAC values, we suggest that 2 mg/m3 and 4 mg/m3 should be considered as the MAC for PM-dust and PCM-dust, respectively, and 3 mg/m3 for P-dust. We believe that establishing different hygiene standards is more accurate even though workers are exposed to the "same" dust.

Air Pollutants, Occupational↗