Respiratory assessment of refractory ceramic fibers in a heating technician population.

Refractory ceramic fibers (RCF) have been extensively used for insulation in condensing boilers. The aim of this study was to evaluate the respiratory exposure to these fibers among maintenance heating technicians. We first created a working group (Carsat Brittany and Finistère Occupational Health Services) and carried out a sampling strategy. Atmospheric measurements were done during work tasks, and filters were analyzed by phase contrast microscopy (PCM) and scanning electron microscopy (SEM) in French approved laboratories. Four companies were included for a total of 15 days of work. During those 15 workdays, 12 SEM and 21 PCM samples were taken and analyzed. The phase contrast microscopy and SEM average results were 0.04 and 0.004 fibers/cm3, respectively. In conclusion, the study confirms heating technician RCF respiratory exposure during maintenance work for both condensation gas boilers and atmospheric boilers. Collective and individual prevention measures should be implemented along with appropriate medical follow-up.

Exposure to phosphine in maritime transport: a real and important occupational risk: a report of three cases.

In maritime transport, to assess the risks of insect pests spreading, fumigation is recommended by the Food and Agriculture Organisation. Fumigant mostly used for foodstuffs is the phosphine gas generated by the reaction of aluminium phosphide and moisture in the atmosphere. In this article, we first discuss phosphine toxicity to humans and then we describe three cases of occupational exposure in maritime transport of cereals. We found phosphine level higher than 20 ppm in tank atmosphere of bulk carriers and levels from 2 to 3.5 ppm in port silos and port warehouses where cereals were unloaded. Two weeks later, atmospheric measurements in a silo were still at 0.8 ppm. In this case, 3 workers described symptoms which could be linked with phosphine. Exposures to phosphine and cases in maritime transport are surely underestimated. Exposure could occur at sea, in harbour but also in port warehouses, trucks and silos or warehouses along logistic chain. All workers in the chain could be exposed. We can recommend research aiming at the development of alternative techniques using a less harmful gas for humans. At individual level, we propose that, along with the training for employees, workers potentially exposed should wear a test strip (phosphine detector strips) or a personal gas badge with appropriate maintenance.