Hazardous waste involving human exposure

As discussed in Section 2.3.3, the mechanism of chloroform-induced liver toxicity may involve metabolism to the reactive intermediate, phosgene, which binds to lipids and proteins of the endoplasmic reticulum, lipid peroxidation, or depletion of GSH by reactive intermediates. Because liver toxicity has been observed in humans exposed to chloroform levels as low as 2 ppm in the workplace and in several animal species after inhalation and oral exposure, it is possible that liver effects could occur in humans exposed to environmental levels, to levels in drinking water, or to levels found at hazardous waste sites. 

The human information is based largely on case reports not epidemiology studies. Chemicals other than organotins were always involved. Exposure levels and durations were not well documented in the human reports and exaggerated doses were used on the animal studies. Despite the uncertainties, neurobehavioral changes must be looked for in persons involved with accidental spills of tin compounds, in industrial settings, or at hazardous waste sites. 

Human exposure to PAHs in the environment today appears to be practically unavoidable. Charcoal grilling of meat (Rivera et al., 1996) and bioaccumulation of PAHs in fish (van der Dost et al., 2003) are two ways by which food may become contaminated with PAHs. Workers involved in the clean-up of hazardous wastes may be at risk from PAH exposure, although smoking is also a factor (Lee et al., 2002). 

Chemical Dosimetry bv TSP LC/MS. One of our long-term objectives in studying TSP LC/MS is the development of chemical dosimetry based on direct determination of polar metabolites in biological fluids. Most toxic substance exposure scenarios (i.e., near hazardous waste sites) involve complex and variable mixtures of substances. Biological monitoring, where human fluids, tissues and excreta are analyzed, measures actual exposure, whereas analysis of soil, air or water can only provide an estimate of potential exposure. Exposure data forms the basis of human health risk assessment, and ultimately defines cleanup requirements at contaminated sites. 

Disease Registries. The only known health effects of NDMA on humans are those obtained from acute poisoning cases, in which postmortem examination revealed severe liver damage. If disease states attributed to exposure to NDMA could be identified by epidemiological studies, the number of individuals affected, the exposure levels involved, and the factors associated with identifying the disease in a given population, such as, the vicinity to hazardous waste sites or industrial plants, could be determined. 

Level 2 precautions stress the use of secondary barriers and making waste decontamination available to reduce contamination. This level of protection is appropriate for tasks involving human blood, body fluids, or tissues. Primary hazards can include percutaneous events, mucous-membrane exposures, or ingestion of infectious materials. Use extreme precaution when working with contaminated needles or sharp instruments. 

The primary objective is to develop an appropriate range of waste management options to be analyzed more fully in the detailed analysis phase of the FS.12 Appropriate waste management ensures the protection of human health and the environment. It may involve, depending on site-specific circumstances, complete elimination or destruction of hazardous substances at the site, significant reduction of concentrations of hazardous substances to acceptable health-based levels, and prevention of exposure to hazardous substances via engineering or institutional controls, or some combination of the above. 

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