Persistent organic pollutant identifying

WHO has conducted three international studies of PCBs, polychlorinated dibenzodioxins, and polychlorinated dibenzo-furans in human milk during 1987-2003 (WHO 2000). The first two surveys were conducted in 1987-1988 and 1992-1993 in a number of European countries. The third, conducted in 2000-2003, included additional countries. A fourth survey has been developed with the intent to assess the persistent organic pollutants (POPs) found in human milk so that each country can better identify and set priorities among POPs for remedial action (WHO 2000). The sample population will include at least 50 mothers from each country who are planning to breastfeed (WHO 2005). Two sampling periods have been proposed, the first to obtain a baseline sample of POPs in representative... 

Abelsohn, A., Gibson, B.L., Sanborn, M.D., Weir, E., 2002. Identifying and managing adverse environmental health effects 5. Persistent organic pollutants. Can. Med. Assoc. J. 166, 1549-1552. 

Polymerization of fluoroolefins in liquid and supercritical carbon dioxide eliminates the use of water and C-8 surfactant that has been identified as a persistent organic pollutant (R. Carbonell) ... 

In Chapter 13, we learned about the "dirty dozen"—12 chemical compounds that have been targeted by governments arotmd the world to be banned. These compounds are known as persistent organic pollutants (POPs) because once they enter the environment, they remain for long periods of time. Examine the structures of the compounds shown here. What functional groups can you identify within the compounds (They may have more than one.) What structural features do many of these compounds have in common ... 

In contrast, consider the characteristics of HCB. The global Stockholm Convention identifies HCB as a persistent organic pollutant (POP). (We revisit the story of HCB in Chapter 4 after looking briefly here at characteristics that influence its environmental fate and transport.) The half-life of HCB is estimated to range from 2.7 to 5.7 years in surface water and from 5.3 to 11.4 years in groundwater [24]. Laboratory experiments have determined BCF values for fish of up to 21,900 [25]. These characteristics help to explain why, in the words of the United Nations Environmental Programme (UNEP), HCB can "remain intact in the environment for long periods, become widely... 

Programs to identify Persistent Organic Pollutants (POPs) and Persistent Bio-accumulative and Toxic (PBT) chemicals are being incorporated into international chemical review programs. Agreements are being made to phase out certain pesticides that meet certain criteria. 

Three types of SRMs are produced by NIST. Neat reagent SRMs and solution SRMs are intended primarily for instrument calibration whereas complex matrix SRMs are better suited for use as control materials. The amoimt of substance present for relevant constituents(s) is usually reported as a mass fraction with stated uncertainty. Values are usually assigned based on measurements from two or more independent methods. This approach is used to help assure the accuracy of the measurements by identifying potential method biases. A list of complex matrix and solution SRMs available from NIST is provided in Table 13.4. Levels of one or more persistent organic pollutant compoimds are reported for each of these environmental SRMs. A listing of CRMs available from other national metrology institutes has also been compiled [206]. 

---