Radioactive-biological Waste

The physical and health hazards associated with chemicals should be determined before working with them This determination may involve consulting literature references. Laboratory Chemical Safety Summaries (LCSSs), Matmal Safety Data Sheets (MSDSs), or other reference materials (see also Chapter 3, section 3.B) and may require discussions with the laboratory supervisor and consultants such as safety and industrial hygiene officers. Every step of the waste minimization and removal processes should be checked against federal, state, and local regulations. Production of mixed chemical-radioactive-biological waste (see Chapter 7, section 7.C.1.3) should not be considered without discussions with environmental health and safety experts. 

Multihazardous waste, (a) Chemical-radioactive waste, or mixed waste," (b) chemical-biological waste, (c) radioactive biological waste, and (d) chemical-radioactive biological waste. 

When possible, select a single management option. Some waste management methods are appropriate for more than one waste hazard. Low-level radioactive animal tissue (a radioactive-biological waste) can often be incinerated on-site, which may be a satisfactory disposal option for both the radioactive and the biological characteristics of the waste. Some multihazardous waste can be disposed of safely in the sanitary sewer when allowed by the local publicly owned treatment works (POTW). 

Basic principles for the management of radioactive-biological waste include the following ... 

Laboratories that have an on-site radioactive waste incinerator have a great advantage in their ability to manage radioactive-biological waste. On-site incineration of radioactive-biological waste is practical and can be done with minimal impact to health or the environment. For waste that is putrescible or may be infectious, on-site incineration is ideal. 

Many laboratories do not have an on-site incinerator for radioactive-biological waste. Communities tend to oppose waste incinerators, and on-site incineration is prohibitively costly for some radioactive-biological waste generators. Even institutions that have incinerators must usually rely on off-site disposal for some of their radioactive waste. For radioactive putrescible waste, off-site disposal requires special packaging, storage, and transport considerations. 

Reliable access to off-site disposal will depend on the establishment of regional sites, which have been slow to develop under the Low-level Radioactive Waste Policy Act of 1980. Moreover, when established, regional low-level radioactive waste sites may not immediately accommodate laboratory radioactive-biological waste. As discussed earlier in this chapter, choice of off-site disposal must involve careful consideration of the safety record of the facOity to ensure that the generator s long-term responsibility is liability-free. 

Certain waste treatments reduce multiple hazards in one step. For example, incineration can destroy oxidizable organic chemicals and infectious agents, waste feed rates can be controlled to meet emission limits for volatile radionuclides, and radioactive ash can be disposed of as a dry radioactive waste. Likewise, some chemical treatment methods (e.g., those using bleach) both oxidize toxic chemicals and disinfect biological hazards. Such treatment could convert a chemical-radioactive-biological waste to a radioactive waste. 

In the past, hazardous wastes were often grouped into the following categories (1) radioactive substances, (2) chemicals, (3) biological wastes, (4) flammable wastes, and (5) explosives. The chemical cate-goiy included wastes that were corrosive, reactive, and toxic. The principal sources of hazardous biological wastes are hospitals and biological-research facilities. 

The laboratory operator must make a careful examination of all wastes that will be generated and, from this, work up a waste disposal system. Some wastes may be compatible and could be disposed of together. Others could react and thus cause problems. Flammables must be given special attention. Certain biological wastes may be very hazardous even in small quantities. Special rules apply to radioactive materials, even in the small amounts used for investigative purposes. 

Do not generate multihazardous waste (combinations of radioactive, biological, and chemical waste) without first consulting with the designated radiation and chemical safety officers. 

Minimize the waste s hazards. Waste minimization methods specific to chemical, radioactive, or biological waste can be applied to multihazardous waste to mitigate or eliminate one hazard, which wOl then allow it to be managed as a single-hazard waste. For example, the substitution of nonignitable liquid scintillation fluid (LSF) for toluene-based LSF reduces a chemical-radioactive waste to a radioactive waste. 

The management of radioactive-biological laboratory waste (shown in Figure 7.2c) can be difficult because of limited on- and off-site disposal options. 

Multihazardous waste is a by-product of various kinds of critically important work in, for example, clinical and environmental laboratories. With the help of several experts as part of a special subcommittee, the committee studied the disposal of various combinations of chemical, radioactive, and biological waste. Few disposal facilities exist for multihazardous waste, and some waste materials are so unique and occur in such small quantities that there is no commercial incentive for developing special legal means for handling them. 

This act bans dumping of radioactive, biological, and chemical warfare wastes in the ocean. It requires permits for dumping of sewage sludge and dredged materials. 

Co-disposal of radioactive and non-radioactive waste among other chemical, industrial, toxic and biological wastes should be carefully analysed as long as the volume of non-radioactive wastes to be disposed in a deep geological repository could be large enough to justify the construction of such a facility in each country. 

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