Lack of in vitro genotoxicity of povidone-iodine in solution, in ointment or in a liposomal formulation (Repithel).

The in vitro genotoxicity of povidone-iodine in Repithel, Betaisodona ointment and Betaisodona solution was investigated using CHO-K1 cells. The comet assay and chromosome aberration test were used to characterise the genotoxic potency of povidone-iodine within 4 h of contact with test cells. Methyl methanesulphonate without S9 activation and benzo[a]pyrene with S9 activation were used as positive controls. No higher concentrations than 6% Repithel, 5% Betaisodona ointment and 2% Betaisodona solution in culture medium with 10% fetal bovine serum were tested within 4 h of contact with CHO-K1 cells for the comet assay, because higher concentrations will provide >60% cytotoxicity. All tested concentrations of povidone-iodine formulations (4-6% Repithel, 3-5% Betaisodona ointment and 1-2% Betaisodona solution) are not genotoxic in the comet assay. 10% Repithel, 5% Betaisodona ointment and 2.5% Betaisodona solution in culture medium with 10% fetal bovine serum were final concentrations in the chromosome aberration test, which provide <60% cytotoxicity within 4 h of contact with CHO-K1 cells. All tested concentrations of povidone- iodine formulations (5-10% Repithel, 2.5-5% Betaisodona ointment and 1.25-2.5% Betaisodona solution) are not genotoxic in the chromosome aberration test. Using the comet assay and chromosome aberration test to characterise the genotoxic potency of povidone-iodine within 4 h of contact with CHO-K1 cells, there was no chromosome damage detected.

An occupational risk survey of a refractory brick company in Ha Noi, Viet Nam.

Viet Nam has an increasing need for building materials, including refractory bricks. Little is known regarding the occupational hazards incurred in brick manufacturing. To determine the occupational health hazards posed by a refractory brick operation in Ha Noi, Viet Nam, a cross-sectional occupational risk survey was conducted, focusing on respirable dust hazards. It included an industrial hygiene walk-through and gravimetric dust analysis. Noise, heat, lack of head protection, and dust exposure were hazards identified at the brick-manufacturing site. Respiratory protection involved a three-layer cloth mask that had not been tested for efficacy. Silica dust exposure levels exceeded the Vietnamese permissible exposure level by almost fivefold based on gravimetric assessment and estimated silica content. This brick manufacturing site contains significant injury and respiratory illness hazards. Further investigations are necessary to begin to develop occupational safety measures at the site.