Safety Standards in Pharmaceutical Compounding, Part 1: The Occupational Safety and Health Administration.

Ensuring a safe working environment for employees is of paramount importance to all responsible compounding pharmacists, and adhering to safety standards established by the U.S. Occupational Safety and Health Administration renders achieving that goal more likely. However, information about such compliance (especially with respect to pharmaceutical compounding) may not be readily available. In this first article in a 3-part series, an overview of Occupational Safety and Health Administration standards that address employee safety in the workplace is provided and pertinent questions of interest to compounders are answered. In series parts 2 and 3, ensuring compliance with those standards is discussed in more detail and issues pertaining specifically to fire prevention in compounding facilities are addressed.

Evaluating measurement error in estimates of worker exposure assessed in parallel by personal and biological monitoring.

BACKGROUND: While studies indicate that the attenuating effects of imperfectly measured exposure can be substantial, they have not had the requisite data to compare methods of assessing exposure for the same individuals monitored over common time periods. METHODS: We examined measurement error in multiple exposure measures collected in parallel on 32 groups of workers. Random-effects models were applied under both compound symmetric and exponential correlation structures. Estimates of the within- and between-worker variances were used to contrast the attenuation bias in an exposure-response relationship that would be expected using an individual-based exposure assessment for different exposure measures on the basis of the intra-class correlation coefficient (ICC). RESULTS: ICC estimates ranged widely, indicative of a great deal of measurement error in some exposure measures while others contained very little. There was generally less attenuation in the biomarker data as compared to measurements obtained by personal sampling and, among biomarkers, for those with longer half-lives. The interval ICC estimates were often-times wide, suggesting a fair amount of imprecision in the point estimates. Ignoring serial correlation tended to over estimate the ICC values. CONCLUSIONS: Although personal sampling results were typically characterized by more intra-individual variability than inter-individual variability when compared to biological measurements, both types of data provided examples of exposure measures fraught with error. Our results also indicated substantial imprecision in the estimates of exposure measurement error, suggesting that greater emphasis needs to be given to studies that collect sufficient data to better characterize the attenuating effects of an error-prone exposure measure.

Assessment of variability in biomonitoring data using a large database of biological measures of exposure.

Although intra- and interindividual sources of variation in airborne exposures have been extensively studied, similar investigations examining variability in biological measures of exposure have been limited. Following a review of the world's published literature, biological monitoring data were abstracted from 53 studies that examined workers' exposures to metals, solvents, polycyclic aromatic hydrocarbons, and pesticides. Approximately 40% of the studies also reported personal sampling results, which were compiled as well. In this study, the authors evaluated the intra- and interindividual sources of variation in biological measures of exposure collected on workers employed at the same plant. In 60% of the data sets, there was more variation among workers than variation from day to day. Approximately one-fourth of the data were homogeneous with small differences among workers' mean exposure levels. However, an almost equal number of data sets exhibited moderate to extreme levels of heterogeneity in exposures among workers at the same facility. In addition, the relative magnitude of the intra- to interindividual source of variation was larger for biomarkers with short compared to long half-lives, which suggests that biomarkers with half-lives of 7 days or longer exhibit physiologic dampening of fluctuations in external levels of the workplace contaminant and thereby may offer advantages when compared to short-lived biomarkers or exposures assessed by air monitoring. The use of biological indices of exposure, however, places an additional burden on the strategy used to evaluate exposures, because data may be serially correlated as evidenced in this study, which could result in biased estimates of the variance components if autocorrelation is undetected or ignored in the statistical analyses.