Aims: (i) To develop an analytical method for recovery and quantification of bacteriophage MS2-as a surrogate for foot-and-mouth disease virus-from complex porous surfaces, with and without the presence of laboratorydeveloped agricultural grime; (ii) to evaluate, with a 4-log dynamic range, the virucidal activity of common biocides for their ability to decontaminate surfaces and hence remediate facilities, following a foreign animal disease contamination incident. Methods and Results: An analytical method was developed and optimized for MS2 recovery from simulated agricultural surfaces. The addition of Dey-Engley neutralizing broth to an extraction buffer improved MS2 viability in liquid extracts, with optimal analytical holding times determined as <8 to ≤24 h, depending on matrix. The recovery of MS2 from surface materials decreased in the order: nonporous reference material >grimed porous materials >nongrimed porous materials. In disinfectant testing, two spray applications of pAB were effective against MS2 (≥4-log reduction) on all operational-scale materials. Two per cent citric acid had limited effectiveness, with a ≥4-log reduction observed on a selected subset of grimed concrete samples. Conclusions: Decontamination efficacy test results can be affected by surface characteristics, extraction buffer composition, analytical holding time and surface-specific organism survivability. Efficacy should be evaluated using a test method that reflects the environmental characteristics of the intended application. Significance and Impact of the Study: The results of this study demonstrate the importance of analytical method verification tests for disinfectant testing prior to application in complex environments.

In 1990 six cases of physician-diagnosed occupational asthma in cosmetologists working with artificial fingernails prompted the Colorado Department of Health to request the assistance of National Institute for Occupational Safety and Health (NIOSH) researchers in the evaluation and control of nail salon technician exposure. A commercially available recirculating downdraft table with charcoal filters was purchased and evaluated. Researchers from NIOSH made modifications to the table that included increasing the downdraft air volume; enlarging the plenum for more consistent airflow rates at the face of the table; removing the charcoal filters while incorporating a ventilation system to the outdoors; and putting an extension around the duct leading to the perforated plate at the downdraft face of the table. An evaluation was performed using the following two configurations: the modified table with the downdraft ventilation on (vented) and without the downdraft ventilation on (unvented). Each of the two configurations was sampled for 3 days in random order. Testing included the use of XAD-2 solid sorbent tubes for determining ethyl methacrylate and methyl methacrylate concentrations. Relative concentrations of organics were examined and used to analyze work practices. The geometric mean ethyl methacrylate exposure for personal breathing zone samples when using the modified table for approximately 6 hours was 0.6 ppm; when using the unventilated conventional table, the geometric mean exposure was 8.7 ppm. The difference in the values is statistically significant (p = 0.0045). Methyl methacrylate concentrations were nondetectable on all sorbent tubes.

Specimens of similar nominal thickness from commercially available nitrile and neoprene gloves were each tested for breakthrough time against three chemicals. The null hypothesis was that the breakthrough times for the glove specimens of the same generic type but produced by different manufacturers would be the same. Breakthrough time data for each material/chemical combination were analyzed using an analysis of covariance to adjust for differences in the measured specimen thickness while testing for product differences. A significant difference in chemical breakthrough times was found among generically similar products produced by different manufacturers. The largest difference between the mean breakthrough time of two generically equivalent products, 30 vs. 300 min, was obtained for perchloroethylene through nitrile products. In conclusion, breakthrough time data for use in selection of chemical protective clothing or in prediction modeling for chemical protective clothing should be manufacturer and product specific.