Warren W. Jederberg

Issues with the Integration of TechnicaL Information in Planning for and RespondinG to NonTraditional Disasters

In the post-9/11 environment, it has become recognized that the response to man-made disasters (such as chemical spills, bioterrorism, and radiation dispersal) requires a much broader range of tools and technical knowledge than needed for natural disasters (i.e., hurricanes, earthquakes, or drought). This need also requires that those who develop technical information for disaster planning maintain a broader perspective of how the information will be used and what the priorities are for developing new information. In addition, the ability to communicate information within a context understandable to the “end user” has become more critical. The intent of this article is to present issues to help those who traditionally collect and interpret technical information (toxicology, risk assessment, mitigation planners, etc.) to better understand how their information is used in planning for and responding to incidents. These issues are similar to those experienced when trying to provide the users of information provided on material safety data sheets (MSDS) with an understanding of the value and limits of such information in decision making. Confounding the problem are the many sources that provide exposure limits and the limited amount of time the user has to understand the limits of the data during an emergency. While the Federal Response Plan integrates the efforts of multiple agencies, the “on-scene” responders are faced with trying to respond to contradictory strategies and applications of information. Sources of response technical information need to better communicate the limits of application/interpretation of that information in emergency situations.

Detection of Resin Acid Compounds in Airborne Particulate Generated from Rosin Used as a Soldering Flux

Various uses of rosin and exposure to its resin acid constituents have been associated with dermal and pulmonary sensitization. Methodology is presented to detect resin acids common to rosin (such as abietic and dehydroabietic acid) found in aerosol from heated rosin flux. Air filtration, solvent filter extraction, and gas chromatography/mass spectrometry were used to provide qualitative and quantitative information on the resin acid content of aerosol produced during soldering with rosin flux. Abietic acid and dehydroabietic acid were identified and quantified in aerosol derived from heated rosin flux, in samples collected in the field and in laboratory generated samples. Other resin acids (including several apparently oxidized resin acids) were detected, but not quantified. Laboratory mass balance experiments using soldering temperatures and liquid rosin flux showed that much of the nonvolatile material originally present in unheated flux may be captured on a sampling filter following heating and aerosolization. The data presented suggest that resin acids are a major component (with regard to mass) of the airborne contaminants produced during soldering with rosin flux. Abietic acid was shown to be unstable on sampling filters held for a period of weeks, while dehydroabietic acid and total solvent-soluble material were not found to degrade under the same conditions. Rosin aerosol produced in the laboratory using a soldering iron and liquid rosin flux produced particles shown to be of respirable size using scanning electron microscopy.

Percutaneous absorption of 2,6-di-tert-butyl-4-nitrophenol (DBNP) in isolated perfused porcine skin

DBNP (2,6-di-tert-butyl-4-nitrophenol) has been reported as a potential contaminant in submarines. This yellow substance forms when lubrication oil mist containing the antioxidant additive 2,6-di-tert-butylphenol passes through an electrostatic precipitator and is nitrated. Percutaneous absorption of 14C-DBNP was assessed in the isolated perfused porcine skin flap (IPPSF). Four treatments were studied (n=4 flaps/treatment): 40.0 microgram/cm(2) in 100% ethanol; 40.0 microgram/cm(2) in 85% ethanol/15% H(2)O; 4.0 microgram/cm(2) in 100% ethanol; and 4.0 microgram/cm(2) in 85% ethanol/15% water. DBNP absorption was minimal across all treatment groups, with the highest absorption detected being only 1.08% applied dose in an aqueous ethanol group. The highest mass of 14C-DBNP absorbed was only 0.5 microgram. The majority of the applied dose remained on the surface of the skin. This suggests that there is minimal dermal exposure of DBNP when exposed topically to skin.

Characterization of the Skin Penetration of a Hydrocarbon-Based Weapons Maintenance Oil

Break-Free CLP is a commercial petroleum-based liquid used for cleaning, lubricating, and protecting firearms that is used in the United States by military personnel, police, and individual gun owners for maintaining a wide variety of firearms. According to its material safety data sheet (MSDS), Break-Free CLP is predominately polyalphaolefin oil but also contains dibasic ester and isoparaffinic hydrocarbons; all of these ingredients are known to induce skin irritation in laboratory animals. Studies completed in our labs found that repeated topical application of Break-Free CLP to the backs of CD-1 mice produced evidence of systemic effects. Studies were conducted to characterize the dermal penetration of Break-Free CLP in mouse, rat, and pig skin to provide insight on possible factors or causes of skin irritation and systemic effects observed in previous studies. Mouse skin was 37 times more permeable to Break-Free CLP than pig skin and 6 times more permeable than rat skin. Flux measurements from static diffusion cells showed an inverse correlation with mouse, rat, and pig skin thickness. The concentration of Break-Free CLP in mouse skin was 4.5 times higher than the amount found in rat skin and about 17 times higher than the amount absorbed by pig skin. These results support the idea that Break-Free CLP causes skin irritation and systemic effects in the mouse by both penetrating through and accumulating in the skin. The findings for rat and pig skin are probably most representative of Break-Free CLP flux into and through unprotected human skin and suggest that dermal toxicity studies in CD-1 mice overestimate the risk to humans. These results, nevertheless, suggest that persons handling or using Break-Free CLP should protect the skin from possible exposure.

Oxidized resin acids in aerosol derived from rosin core solder.

Exposure to rosin during a variety of uses has been associated with dermal and pulmonary sensitization. Oxidized resin acids are present in many rosin products, and have been regarded as the main sensitizing rosin compounds in cases of dermal sensitization. This research describes oxidized resin acids identified in aerosol produced during soldering with rosin core solder. Oxidized resin acids found were 7-oxodehydroabietic acid, 15-hydroxydehydroabietic acid, and 7-hydroxydehydroabietic acid. The presence of oxidized compounds known to be dermal sensitizers in aerosol from rosin flux soldering supports the hypothesis that resin acid compounds are pulmonary sensitizers as previously proposed. Changes in the composition of resin acid aerosol derived from heated rosin core solder (compared with the parent material) are described.

Estimation of the Health Risks Associated with Polychlorinated Biphenyl (PCB) Concentrations Found Onboard Older U.S. Navy Vessels

PCBs have been identified on surfaces and in component materials and equipment from inactive U.S. Navy nuclear submarines commissioned prior to 1970. Health risks associated with PCBs present onboard submarines were estimated for hypothetical crew members and shipyard workers. Median non-cancer hazard quotients for shipyard workers and submarine crew ranged between 0.4-54.6, with the highest quotients estimated for unprotected shipyard workers. Median cancer risk estimates ranged from 7.3 x 10(-6) to 1.1 x 10(-3) with the highest estimated risk calculated for unprotected shipyard workers. Our findings suggest that PCB surface concentrations found onboard inactive nuclear submarines commissioned prior to 1970 may be high enough to constitute a possible risk to the health of persons involved in dismantling of Navy submarines if PCB exposure is not minimized. Potential sources of uncertainty in our risk assessment include the correlation between PCB contamination levels on inactive versus active nuclear submarine vessels, the relationship between wipe sample concentrations and human exposure, dermal contact frequency with PCB-contaminated surfaces, carcinogenicity of PCBs in humans, and uncertainties inherent with the PCB cancer slope factor and oral RfD. Our findings support Navy policy that shipyard workers should wear personal protective equipment when PCB contamination is suspected or has been identified and that IH surveys should continue to identify sources of PCB contamination onboard vessels and reduce PCB contamination to concentrations that are reasonably achievable.

EXPOSURE ASSESSMENT AND THE HEALTH OF DEPLOYED FORCES

ABSTRACT The risk assessment process is a critical function for military Deployment Toxicology research objectives, emphasizing improved health protection of deployed forces. Reliable risk assessment methodology is essential for decision making related to risk reduction procedures during combat deployment, as well as during routine occupational activities. Such decision making must be based upon quality science that both guides sound judgments in risk characterization and management, and provides necessary health protection tools. The health and fitness of deployed forces must be considered for both acute and long-term issues. Exposure assessment specifies populations that might be exposed to injurious agents, identifies routes of exposure, and estimates the magnitude, duration, and timing of the doses that personnel may receive as a result of their exposure. Acute or short-term catastrophic risks for deployed forces are of immediate concern and must be addressed on a risk prioritization basis using Operational Risk Management (ORM) procedures. However, long-term effects of exposure to the same agents must be considered as part of the overall health concerns for deployed forces. In response to these needs, a number of military, federal government, academic and private sector organizations are currently developing new classes of biologically-based biosensors with the programmed capacity to detect the presence of virtually any environmental chemical or biological stressor with the capacity to induce health consequences in deployed personnel. A major objective of this engineering effort is development of biosensor systems that detect novel (previously unresearched) chemical or biological agents that might be used during international combat or terrorist attacks to induce acute or long-term health effects on military or civilian populations. A large portion of the discussion in this paper is devoted to describing the development, testing, and implementation of tissue-based biosensors (TBBs) that utilize small samples of living tissue from laboratory small animals for a wide range of human risk assessment applications.

The assessment of Health Risk to Occupationally Exposed Navy Personnel: A Consideration of Issues

AbstractOccupational exposures of Naval personnel to toxic chemicals and other substances occur continually by virtue of their jobs and the mission of the Navy. Such exposures are similar to, yet in many respects distinct from, either occupational exposures of civilian workers or environmental exposures of the general population. Primary dissimilarities may include the duration of exposure, the intermittent nature of exposure, and the age, health, and physical condition of the exposed population. Although the length of individual exposures may be similar, the cumulative time in which a worker is exposed is likely to be different. Any exposures at a given duty station are often intermittent, with prolonged (days or months) exposure-free periods in between. The Navy, therefore, is faced with developing an occupational risk assessment paradigm specific to, and appropriate for, the types of occupational exposures experienced by Navy personnel in the performance of shipboard or other duties. Acceptable risk mu...