Similarly, the stability of many organofluorines has raised the issue of biopersistence.

Organofluorines exhibit biopersistence due to the strength of the carbon-fluorine bond.

Critics of chlorine-based products have pointed to their high chemical resistance and biopersistence as risks to the environment.

While the concept of biopersistence is important, quantitative procedures for evaluation of this parameter have not been established.

Results of recent studies indicate that biological response may correlate well with biopersistence in the lung (McClellan et al., 1992).

Its biopersistence is below the threshold for classifying synthetic fibres as carcinogenic, according to the European Union.

Massive balloon releases gained popularity during the 1980's, and fell out of popularity following research on the biopersistence, distance-travelled, and gastronomical effect on animals.

This 'biopersistence' has been likened to that of asbestos; ways to neutralise the toxicity of this engineered material have been avidly sought.

Played a leading role in the organization and delivery of two successful workshops on aquatic toxicity, bioaccumulation, and biopersistence for sparingly soluble metals and mineral compounds.

Durability, a phenomenon related to the biopersistence of inhaled particles inside lung tissues, is believed to be an important parameter in determining the pathogenicity of inhaled solid materials.

Fibre diameter and length are primary determinants of penetration into the respiratory system, access to translocation pathways, surface properties and biopersistence which, in turn affect the potential for biological response.

Data presented at the Symposium showed that various types of glass fibres also have different solubilities and biopersistence characteristics, which may vary according to their respective manufacturing process and chemical composition.

Based on studies of synthetic fibres, it has been suggested that fibres of low biopersistence pose a lower lung cancer and mesothelioma risk than those of higher biopersistence.

One of the major advances in the understanding of the mechanisms of fibre-related disease over the last decade or so has been the role of biopersistence or the durability of a fibre in lung tissue.

Neil Johnson and Brooke Mossman review current knowledge of factors influencing dose-effect relationships for chrysotile, including level of exposure, physical dimensions of the fibres, and biopersistence of the retained fibres in the lung.

"We continued to increase our emissions into the river in spite of internal commitments to reduce or eliminate the release of this chemical into the community and environment because of our concern about the biopersistence of this chemical."

The results of studies of biopersistence in lung tissue in vivo, and solubility in physiological fluids in vitro, have varied widely for different MMVF and within each of the types of MMVF.

The European Certification Board for mineral wool products, EUCEB, certify mineral wool products made of fibres fulfilling Note Q ensuring that they have a low biopersistence and so that they are fast removed from the lung.

From 1990, the Colt Foundation, relevant industries and the Health and Safety Executive supported a programme of laboratory research into the health effects of man-made mineral fibres that helped to clarify the quantitative relationships between health risks and fibre dimensions and biopersistence.