Exposure and Toxicology

The number of workers with potential beryllium exposure is not known, although estimates in the United States have ranged from 134,000 workers currently exposed to 800,000 individuals currently and previously exposed (17,39,40). It is likely that these numbers underestimate the actual number of exposed individuals, as it is difficult to estimate the number of downstream users of beryllium and former workers, and it does not include estimates outside the United States (1). The prevalence of CBD, from 20 epidemiologic studies, has been estimated at 1% to 5% of exposed workers, depending on the group of workers studied 

Certain beryllium industrial processes and job tasks increase the risk of developing an immune response to beryUium and disease (Table 2) (13,23,24,26,27,29,31,32,48). Although the precise exposure-response relationship for CBD, continues to be the subject of study, it does not appear to be 

Ceramics Dry pressing Firing Forming Lapping Machining Process development Ventilation maintenance 

Nuclear weapons Construction Heath physics Casting Machining Metallurgy 

Beryllium alloy finishing Point and chamfer Wire annealing Wire drawing Wire pickhng 

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Crop protection chemicals undergoing field testing to determine dissipation, wildlife exposure and toxicological effects will have undergone extensive laboratory tests to... 

Danerud PO, Eriksen GS, Johannesson T, et al. 2001. Polybrominated diphenyl ethers occurrence, dietary exposure, and toxicology. Environ Health Perspect Suppl 109 49-68. 

Although most metals occur in nature in rocks, ores, soil, water, and air, levels are usually low and widely dispersed. In terms of human exposure and toxicological significance, it is anthropogenic activities that are most important because they increase the levels of metals at the site of human activities. 

Darnerud, P.O., Eriksen, G.S., Johannesson, T., Larsen, P.B., Viluksela, M., 2001. Poly-brominated diphenyl ethers Occurrence, dietary exposure, and toxicology. Environ. Health Perspect. 109, 49-68. 

The following pages provide brief information on a few selected solvents, including the manner of exposure and toxicological effects on laboratory animals and on humans. For purposes of easy and quick identification and reference by the nser, the solvents are listed in alphabetical order rather than according to the chemical classes to which they belong. The chemical class of each solvent may be fonnd in Appendix 4.1. For more detail on each of the chemical substances, refer to the literature. ... 

For the NIAS, there is a more urgent need due to Article 3 of the Framework Regulation (EC 1935/2004) and new upcoming legislation and the same approach to exposure should be used. The only drawback to the NIAS is the fact that these substances are often unknown and thus the toxicity of these substances cannot be used, and therefore it is almost impossible to apply the acceptable or tolerable intake of these NIAS. The combination of actual exposure and toxicology will help to determine the acceptable level of a specific migrant in the migration extract. 

The following discussion centers on uncertainty related to the estimation of human exposure. Many of the general principles will be applicable to both exposure and toxicology, and the connection and context of this treatment of uncertainty associated with toxicological determinations will be made later in this discussion. 

Brazell, R.S., Moneyhun, J.H., and Ilolmberg, R.W., Chemical characterization and toxicological evaluation of airborne mixtures. Chemical and physical characterization of phosphoms smokes for inhalation exposure and toxicology studies. Report ORNL/TM-957I, AD-AI53, Oak Ridge National Laboratory, Oak Ridge, TN, 1984. 

As JP8 was phased into the military inventory, exposed personnel began voicing concerns about the potential health effects of exposure. Aircraft groundcrew members reported objectionable odors, skin irritation, dizziness and the persistent taste of jet fuel long after exposure. These concerns prompted the Air Force Surgeon General to task the Air Force Institute for Environment, Safety and Occupational Health Risk Analysis (AFIERA) and the Air Force Research Laboratory (AFRL) to address personal exposure and toxicological hazards from JP8. 

In nonindustrialized countries it is feared that, without legislative measures, considerably enhanced production and consumption will lead to similar or even worse Cd pollution as has occurred in the past in industrialized countries. There are no known beneficial effects of Cd, and the available literature on the exposure, pollution, and toxicology of Cd is enormous and still growing. Many conferences, symposia, colloquia, and workshops have been - and will continue to be - dedicated to Cd and its associated problems. It is impossible to deal with all problematic aspects of Cd within the scope and limits of this chapter hence a selection has been made of the most important issues of the exposure and toxicology of Cd. 

Thus we rely first on animal studies designed to show the relations of pesticide exposure and toxicological effects. 

This guidance clearly illustrates EPA s preference to base regulatoiy decisions on in vivo rat studies. The rat has been selected not on its predictability to human in vivo absorption but rather on its ability to link to other exposure and toxicology data collected in this species. Dermal absorption data collected using procedures similar to those employed with inhalational or oral gavage studies in rats provide a basis for route-to-route extrapolations. 

Pestka JJ. Deoxynivalenol mechanisms of action, human exposure, and toxicological relevance. Arch Toxicol. 2010 84 663-679. 

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