Semivolatile organic priority pollutants

Table II. Summary of Methods for Semivolatile Organic Priority Pollutants...

Fisher, J. A., Scarlett, M. J., and Stott, A. D., Accelerated solvent extraction an evaluation for screening of soils for selected U.S. EPA semivolatile organic priority pollutants. Environ. Sci. TechnoL, 31, 1120-1127, 1997. 

Method 625 for Semivolatiles. This method is a solvent extraction method intended to determine as many of the organic semivolatile priority pollutants as possible. To accomplish this, the sample is serially extracted, first at a pH greater than 11 and then at pH 2. Figure 1 shows a flow diagram of the procedure. The two fractions, base-neutrals and acids, are independently determined by using two separate GC columns. The base-neutrals are determined on a 1.8-m X 2-mm i.d. glass column packed with Supelcoport (100-120 mesh) coated with 3%... 

Table 1.6 List of Priority Pollutant Semivolatile Organics Quantitated with Respect to the Internal Standard Phenanthrene-dio...

Percent recoveries for 21 representative semivolatile priority pollutant organic compounds are listed in the method taken from the categories of base (B), neutral (N), and acid (A), the so-called BNAs from the over 100 compounds that are routinely monitored for in EPA-contract-type work. 

Reversed-phase SPE is applied principally in two areas of TEQA. The first application is in the determination of organochlorine pesticides (OCs) in connection with the determinative technique of GC using a chlorine-selective detector. The second application is in the determination of priority pollutant semivolatile organics that are adequately recovered from drinking water. Off-line RP-SPE coupled to a determinative technique such as GC using an element-selective detector is a very powerful combination with which to achieve the objectives of TEQA. To illustrate, this author s study of various organophosphorous pesticides (OPs) from spiked water using RP-SPE will now be discussed. 

The EPA organics protocol (refer to Fig. 1.2), classifies priority pollutant organics based on the degree of volatility and the volatile and lower-molecular-weight semivolatile regions of Fig. 4.1 are predominantly GC. 

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