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Eugene M White

Publications and source records attributed to Eugene M White.

5 recordsLinked to original sources
PubMed2006

History and results of the two inter-laboratory round robin endotoxin assay studies on cotton dust.

BACKGROUND: In the US cotton industry, airborne cotton dust levels are regulated, and other countries are moving to specify safety limits for airborne endotoxins. There is concern about potential respiratory health hazards associated with agricultural and other organic dusts. In laboratories, ranking which samples have high and low levels of endotoxin is usually in good agreement between laboratories. When different laboratories assay identical samples, the levels differ. The objective of this research was to evaluate the intra- and inter-laboratory variability for 13 laboratories measuring endotoxin in cotton dust. METHOD: Two inter-laboratory round robin endotoxin assay studies were conducted using cotton dust. In the first round robin, each laboratory used their normal in-house assay method and then used a common extraction protocol. In the second round robin, a common extraction protocol and endotoxin assay kit was used. RESULTS: The intra-laboratory results had small variations but inter-laboratory results had very high variations. The inter-laboratory results using a common extraction protocol showed reduced differences. Using the same extraction protocol and endotoxin assay kit, the intra-laboratory variation was small and inter-laboratory variation was reduced but not enough for inter-laboratory agreement. Most of the laboratories were able to discern between the high and low endotoxin concentration dusts. CONCLUSIONS: Standardization has reduced the differences in results between laboratories and possibly further standardization may bring closer inter-laboratory agreement.

Air Microbiology↗
PubMed2006

Metalworking fluid mist occupational exposure limits: a discussion of alternative methods.

NIOSH published a recommended exposure limit (REL) for metalworking fluids (MWF) in 1998 that was designed to prevent respiratory disorders associated with these industrial lubricants. The REL of 0.4 mg/m(3) (as a time-weighted average for up to 10 hours) was for the fraction of aerosol corresponding to deposition in the thoracic region of the lungs. This nonregulatory occupational exposure limit (OEL) corresponded to approximately 0.5 mg/m(3) for total particulate mass. Although this REL was designed to prevent respiratory disorders from MWF exposures, NIOSH acknowledged that exposures below the REL may still result in occupational asthma and hypersensitivity pneumonitis--two of the most significant respiratory illnesses associated with MWF. In the 8 years since the publication of the NIOSH MWF REL, neither the Occupational Safety and Health Administration (OSHA) nor the American Conference of Governmental Industrial Hygienists (ACGIH) has recommended an exposure limit for water-soluble MWF specifically, other than their previous exposure limits for mineral oil. An informal effort to benchmark companies involved in the manufacture of automobiles and automotive parts in North America indicated that most companies are using the NIOSH MWF REL as a guide for the purchase of new equipment. Furthermore, most companies have adopted a goal to limit exposures to below 1.0 mg/m3. We failed to find any company that has strictly enforced an OEL of 1.0 mg/m(3) through the use of either administrative controls or personal protective equipment, when engineering controls failed to bring the exposures to below this limit. We also found that most companies have failed to implement specific medical surveillance programs for those employees exposed to MWF mist above 1.0 mg/m(3). Organization Resources Counselors (ORC) published in 1999 (on their website) a "best practices" manual for maintaining MWF systems and reducing the likelihood of MWF-related illnesses. The emphasis of this approach was on control techniques, and there was no assignment of a specific OEL for MWF due to the wide variety of fluids that exist. The ORC did suggest that maintaining exposure levels to below 2.0 mg/m(3) would assist in minimizing upper respiratory complaints associated with MWF. Although the ORC manual indicated that MWF vary in composition and no single OEL is likely to be appropriate for all such fluids, it adopted a very similar concept to control banding, placing all MWF operations into a single band using similar (if not identical) controls. OSHA, in lieu of adopting a 6B health standard for MWF, has also published a voluntary "best practices" manual on their website. Their document drew heavily from the work of ORC and also incorporated information from the 1998 NIOSH MWF criteria document. Industrial users of MWF need to have guidance, such as an OEL, to determine when either engineering, administrative controls, or personal protective equipment must be implemented to protect their employees. The purpose of this article is to explore various approaches that might be taken to result in a single or multiple limits for exposures to MWF and its components. Approaches such as control banding are discussed in terms of an alternative to the use of an OEL.

Aerosols↗
PubMed2003

Effects of fluid composition on mist composition.

In a reported study, mists of selected synthetic metalworking fluids were generated in laboratory experiments by two processes, nebulization (atomization) and air sparging (bubbling). Short-chain fatty acid species were determined by in situ trimethylsilyl derivatization. Comparison of relative amounts of the short-chain acids collected from mists generated by nebulization with those generated by sparging showed that the sparged mists had significantly higher amounts of neodecanoic, nonanoic, and dodecanedioic acids. Comparison of the amounts of acids collected by the resin cartridges to amounts found on the filters showed that significant losses of octanoic and isononanoic acids occurred over 8 hours of collection and that only dodecanedioic acid was not lost from the filter over a 22-hour sampling period. In another reported metalworking mist study, contaminants of metalworking fluids, e.g., tramp oils, were shown in laboratory experiments to increase the misting potential of water-based metalworking fluids. Significantly, tramp oil contamination caused less misting in synthetic fluids than soluble and semi-synthetic fluids.

Air Pollutants, Occupational↗
PubMed2002

Second inter-laboratory study comparing endotoxin assay results from cotton dust.

Previously, a large two-part inter-laboratory round robin endotoxin assay study was completed. This first study showed that when cotton dust samples, which are practically identical, are assayed for endotoxin that the intra- laboratory results had a very small variation while intra-laboratory results of the sample had a very high variation. In the first part of the study, each laboratory followed its own in-house assay protocol; but in the second part of the study, when the extraction protocol was standardized, the inter-laboratory results showed a lower variation, which suggested that with further standardization, further reduction of differences between laboratories might be achieved in order that results between laboratories would become more comparable. The results stimulated interest in extending the study to include cotton dust with two levels of endotoxin, standardization of the extraction protocol, and using the same assay kit from the same production lot. The results of this second round robin endotoxin assay study indicate that differences between laboratories are still high, but most of the laboratories could discern the cotton dusts with the different levels of endotoxin.

Chemistry Techniques, Analytical↗