STUDIES OF HYDROCARBONS IN MINERAL DUSTS. THE ELUTION OF 3:4-BENZPYRENE AND OILS FROM ASBESTOS AND COAL DUSTS BY SERUM

Particle toxicology and health - where are we?

BACKGROUND

Particles and fibres affect human health as a function of their properties such as chemical composition, size and shape but also depending on complex interactions in an organism that occur at various levels between particle uptake and target organ responses. While particulate pollution is one of the leading contributors to the global burden of disease, particles are also increasingly used for medical purposes. Over the past decades we have gained considerable experience in how particle properties and particle-bio interactions are linked to human health. This insight is useful for improved risk management in the case of unwanted health effects but also for developing novel medical therapies. The concepts that help us better understand particles' and fibres' risks include the fate of particles in the body; exposure, dosimetry and dose-metrics and the 5 Bs: bioavailability, biopersistence, bioprocessing, biomodification and bioclearance of (nano)particles. This includes the role of the biomolecule corona, immunity and systemic responses, non-specific effects in the lungs and other body parts, particle effects and the developing body, and the link from the natural environment to human health. The importance of these different concepts for the human health risk depends not only on the properties of the particles and fibres, but is also strongly influenced by production, use and disposal scenarios.

CONCLUSIONS

Lessons learned from the past can prove helpful for the future of the field, notably for understanding novel particles and fibres and for defining appropriate risk management and governance approaches.

Effect of coal rank on the interferon system

Studies on the induction of interferon by influenza virus in monkey kidney (LLC-MK2) cell monolayers pretreated with coal dust revealed that the inhibitory activity of the mineral on this process was related to coal rank. Maximal inhibition of viral interferon induction was noted with high rank coal and the degression of this activity was related to coal's position in the carboniferous series; anthracite, bituminous, subbituminous, lignite, and peat. The cytocidal activity of each rank of coal, however, was comparable in relation to the corresponding quantities of coal dust that were tested indicating that findings related to interferon production are not explicable on the basis of remaining viable cells. Coal dust, irrespective of rank, also did not affect the ability of exogenous interferon to confer antiviral cellular protection. An inverse relationship mediated by coal of different rank occurred between influenza virus growth and interferon levels which suggested that increased virus growth reflected the ability of higher rank coal to affect adversely interferon production.

Histopathological studies on experimentally induced pulmonary, pleural and peritoneal neoplasms in mice by intraperitoneal injection of chrysotile asbestos and N-methyl-N-nitrosourethane

The cocarcinogenic effects of asbestos are presented. In lung carcinomas induced in mice, the number of carcinomas and the time of detection of the first carcinoma per tumor-bearing animals were greater and faster in the group with chrysotile plus MNU than either chrysotile or MNU alone. This suggested that chrysotile asbestos had a promoting or cocarcinogenic effect on some carcinogens in the respiratory tract. In the group treated with chryotile alone, a tumor was found in the right pleural cavity at 15 months. This tumor microscopically was similar to the biphasic form of the human diffuse mesothelioma. Microvilli, basement membrane, and junctional apparatus were seen by electron microscope, but other cytoplasmic organelles of the tumor cells were relatively scanty. Two peritoneal tumors developed in gastric and intestinal serosa at 11 and 12 months. Light and electron microscopic studies suggested that the tumors were probably myosarcomas or fibrosarcoms.