Occupational health and safety in small enterprises.

Health and work are two central components of sustainable development. A total of 2.6 billion people constitute the global labour force, 80% of which is in the developing world. A significant part of the working population in both developed and developing countries is employed in so-called small-scale enterprises (SSEs). This is the under-served working population which does not fully benefit from available knowledge and experience related to health and safety at work. The focus of this paper includes common features of SSEs, with some key WHO documents and publications on chemical hazards, safety, and emergency measures, as well as the WHO concept on Occupational Health for All, and the WHO Global Strategy.

Toward WHO-recommended occupational exposure limits.

The WHO Project on Recommended Health-based Limits in Occupational Exposure resulted in the development of occupational exposure limit (OEL) values for a few groups of widely used industrial chemicals. A comparative analysis of the WHO-recommended OEL and existing OEL in selected countries has been made. It was shown that in the OEL's development, there is need for harmonization of methodology, approaches and definitions. Therefore, a new WHO project on guiding principles and guidance values for health-based occupational exposure limits has been established.

[Data for the assessment of maximum allowable concentration of dust in the air of work zone during production of permanent magnets based on samarium and cobalt]. / Materialy k obosnovaniiu predel'no dopustimoi kontsentratsii pyli kompozitsii postoiannykh magnitov na osnove samariia i kobal'ta v vozdukhe rabochei zony.

The hygienic studies revealed that one of the most unfavourable factors in permanent magnet production is presented by the composite dust of cobalt and samarium. The toxico-hygienic assessment of the composite determined its MAC in the working zone air at the level 0.05 mg/m3 (as to cobalt).

The body distribution and biological action of xenobiotics.

The authors explored the tissue and intracellular distribution in the body of xenobiotics (aniline-1-14C hydroclorate, dioxane-1,4-14C, toluol-1-14C, phenol-1-14C and 1,2-14C ethylene glycol) following their administration in single doses to white rats. The distribution of the tested substances in the body was correlated with their toxic effects. An analysis of distribution coefficients revealed a multifactorial nature of the distribution in the body of xenobiotics--environmental pollutants. A key role in the distribution of xenobiotics in the body is attributed to histohematic barriers which provide for the selective accumulation of xenobiotics in tissues by utilizing existing modes of active and passive membrane transport. The polytropic nature of the biological effects typical of most chemical environmental pollutants is accounted for by their multireceptor interactions in the body as well as by membrane damage resulting in the distortion of genetic information and, consequently, disorganization of metabolic processes.

Biological effects of asbestos in relation to control of occupational exposure.

The health risks of asbestos exposure and the adequacy of measures to limit the biological effects of exposure are discussed. The toxicological properties of asbestos are considered, and it is postulated that a nonthreshold approach could be used to establish an appropriate permissible level of occupational exposure to the substance.