The asbestos dilemma: II. The ban.

This article reviews the history of legal steps which led to conflicting regulatory approaches to the use of asbestos between the EU, the US and the rest of the world. Particular attention is paid to the EU ruling out the use of all types of asbestos. The author criticizes how the Scientific Committee on Toxicity, Ecotoxicity and the Environment of the European Commission altered their own opinion within as short a time as seven months, and points out the weaknesses of the scientific justification for the EU ban.

The asbestos dilemma: I. Assessment of risk.

This paper gives a critical review of current problems related to quantitative health risk assessment of exposure to asbestos, and particularly to chrysotile, the only type of asbestos still available on the market. The paper reviews types, sources, uses and the main recognised health effects of asbestos, paying particular attention to the health-related properties of fibres and the role of their biopersistence. The main focus is on yet unresolved issues which introduce a large margin of uncertainty into the published quantitative risk assessments: 1) Are all asbestos types equally dangerous or is chrysotile asbestos less dangerous than amphiboles? 2) Are health effects of asbestos fibres threshold or non-threshold effects? 3) Are errors in mathematical modelling of risks so great as to make the risk evaluations worthless? Attention is also given to errors in estimates of past exposures, uncertainties and unspecificities of models and to the unfeasibility of practical application of some well recognized risk assessment models.

[Inhaled insoluble fibres--a significant health problem].

A survey of experimentally and/or epidemiologically proved effects of most frequent insoluble airborne fibres is presented. The most important health-related properties of fibres, important in the quantitative health risk assessment and prognosis, are described. The difference is emphasized between the effects of various asbestos types as well as the difference of toxicity and carcinogenicity between carcinogenic asbestos fibres and the fibres recommended as substitutes for asbestos.

[Byssinosis--an occupational disease of textile workers].

Byssinosis as a nonspecific chronic respiratory disease in textile workers exposed to cotton, hemp and flax is described. Pathogenesis and ethiologic factors responsible for bissynosis are listed. Clinical symptoms of byssinosis and differential diagnosis with occupational asthma are presented.

Are chlorine-free compounds a solution for health problems caused by ozone-depleting substances?

In January 1996, the Government of Croatia and United Nations Environment Programme (UNEP) signed an agreement on the phasing out of ozone-depleting substances in Croatia, making the problem of identifying adequate substitutes a high priority. In this paper, the main ecologic characteristics of chlorine-containing fully halogenated chlorofluorocarbons (CFCs) and partially halogenated chlorofluorocarbons (HCFCs) compared with chlorine-free hydrofluorocarbons (HFCs) are presented. The data showed HCFCs to be ecologically more acceptable than CFCs, particularly regarding the ozone-depleting potential (ODP), and have therefore been proposed as substitutes for CFCs.

Is chrysotile asbestos exposure a significant health risk to the general population?

The main unresolved issues concerning environmental exposure to chrysotile asbestos of the general population are discussed. A review of the results of the measurement of airborne chrysotile fibres in buildings is presented showing that the results have been consistently low with the exception of buildings with damaged friable asbestos-containing material. Quantitative risk assessments are presented indicating that the lifetime risk is small compared to many other environmental risks.

Interconvertibility of asbestos fibre count concentrations recorded by three most frequent methods.

Simultaneous airborne chrysotile asbestos fibre samples were collected with three types of instruments, namely, the konimeter, the thermal precipitator and the membrane filter, in four asbestos plants (textile manufacturing, asbestos cement production, mining, milling). Linear regression analyses were performed of the membrane filter on the konimeter and thermal precipitator count concentrations, respectively. Sampling was performed at 24-35 locations in each of the processes studied.

Relationship between cumulative occupational exposure to asbestos fibres and respiratory symptoms.

A survey of chronic respiratory symptoms was undertaken in 1127 asbestos workers engaged in asbestos mining, asbestos cement production, production of friction materials or in the manufacture of asbestos textile. A control group of 593 persons was also surveyed. The exposure of asbestos workers was analysed by evaluating separately the cumulative exposure to total airborne particles and to airborne asbestos fibres.

[Is it necessary to remove fibrous insulation material from buildings?].

Because of potential negative health effects of exposure to airborne fibres, removal of fibrous insulating materials from buildings, particularly asbestos, has become a frequent, in many cases unjustified, undertaking. The results are presented of the determination of airborne mineral respirable and non-respirable fibres, fragments and total airborne dust in a public building before the substitution of the insulating material, shortly after, and about two months later. There were no differences (P greater than 0.

Ventilatory lung function changes in family members of asbestos workers.

A group of 114 adult family members of asbestos workers were examined for the prevalence of chronic nonspecific respiratory symptoms and ventilatory function changes. There was no difference in the prevalence of any respiratory symptom between the examinees and the matching members of the general population in the study areas. No difference was found between the measured and predicted values of FVC or FEV, or FEF50 in either smoking or nonsmoking men (P greater than 0.

[Chlorofluorocarbons--a new environmental health problem].

A review of health problems caused by the use of chlorofluorocarbons--chemical substances of widespread and varied applications is presented. There is a recent evidence that fully halogenated chlorofluorocarbons are air pollutants inducing hazardous health effects. Direct effects of chlorofluorocarbons on respiratory and cardiac functions are described among which some with lethal outcome.

Immunological and respiratory changes in coffee workers.

Immunological status and respiratory function were studied in a group of 45 coffee workers. Skin tests with coffee allergens demonstrated the highest percentage of positive reactions to dust collected during emptying bags (40.0%), followed by dust of green (12%) and then roasted coffee (8.

Respiratory function in coffee workers.

Respiratory function was studied in three groups of workers employed in processing coffee. The prevalence of almost all chronic respiratory symptoms was significantly higher in coffee processors than in control workers. In each group during the Monday work shift there was a significant mean acute decrease in the maximum expiratory flow rate at 50% vital capacity (VC), ranging from 4.