dioxin 2003 boston session summary report rapid screening methods keith worrall takeshi nakano l.
Download
Skip this Video
Download Presentation
DIOXIN 2003 BOSTON SESSION SUMMARY REPORT Rapid Screening Methods Keith Worrall & Takeshi Nakano

Loading in 2 Seconds...

play fullscreen
1 / 41

DIOXIN 2003 BOSTON SESSION SUMMARY REPORT Rapid Screening Methods Keith Worrall & Takeshi Nakano - PowerPoint PPT Presentation


  • 213 Views
  • Uploaded on

DIOXIN 2003 BOSTON SESSION SUMMARY REPORT Rapid Screening Methods Keith Worrall & Takeshi Nakano. This session is comprised of approximately 19 presentations covering a variety of screening methods for POPs.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'DIOXIN 2003 BOSTON SESSION SUMMARY REPORT Rapid Screening Methods Keith Worrall & Takeshi Nakano' - jarrett


Download Now An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
dioxin 2003 boston session summary report rapid screening methods keith worrall takeshi nakano
DIOXIN 2003 BOSTONSESSION SUMMARY REPORTRapid Screening MethodsKeith Worrall & Takeshi Nakano
slide2
This session is comprised of approximately 19 presentations covering a variety of screening methods for POPs.
slide4
The session covers a diverse range of possible screening methods, developed by colleagues from a wide range of nationalities.
slide5

Presenters are from Australia, Japan, United Kingdom, Norway, Spain, Sweden, USA, Netherlands and Hong Kong will participate in the session.

slide6

For a considerable amount of time, High Resolution GC High Resolution Mass Spectrometry (HRGC-HRMS) methods have been the legislative and accepted methods for the determination of Dioxins, Furans and similar compounds in the analytical laboratory.

slide7

Whilst very accurate, these methods can be time consuming and costly. The aim of this session is to present methods that are being proposed for the rapid screening of a wide variety of matrices.

slide8

There are a number of possible methods of screening, in this session the emphasis is split between bioassay monitoring, instrumental methodsand bio-monitoring.

slide9

In the first of the Oral presentations, Leeuwen and colleagues report on the validation of a wide range of screening methods, with good accuracy and repeatability obtained.

slide10

Anderson and colleagues have worked on a comparison of a rapid biological screening method(EPA 4425) and chemical analytical methods.

slide11

In a study concentrating upon ash, exhaust gas and soil samples, they have concluded that the comprehensive screening of a site using method EPA 4425,

slide12

followed by confirmation analysis of 10-20% of the samples by HRGC-HRMS methods presents the possibility for substantial project savings for a large site.

slide13

This work is complemented nicely by the work of Leeder and colleagues, who present their work looking at the applicability of EPA method 4025 for dioxin site assessment.

slide14

The conclusions are that the method does provide an effective approach to the assessment of sewage treatment plants, being low cost, and having improved turnaround times when compared with EPA method 8290.

slide15
Kobayashi and colleagues present an evaluation of an ah-immunoassay® screening method for PCDD/Fs and dioxinlike compounds.
slide16

The assay employs an efficient clean-up method to remove possible interfering compounds such as PAHs, which results in good correlation with HRGC-HRMS techniques.

the range of sample matrices covered offers a useful tool for routine environmental screening
The range of sample matrices covered offers a useful tool for routine environmental screening.
slide18

Nishi and colleagues have developed an immunochromatographic test highly specific for PCBs, allowing possible results to be obtained at the point of sampling.

slide19

Rivera and colleagues have studied the use of mosses as bio-monitors. The properties of mosses make them a suitable substrate for monitoring,

slide20
as any contamination present will not be taken from the substrate on which they grow, or transferred to internal tissues.
slide21

The conclusions demonstrate that the congener profiles are maintained following deposition on the moss, indicating that no metabolic or transfer effects occur within the organism.

slide22

Ohno and colleagues are presenting an enzyme linked immunoassay (ELISA) technique that shows high selectivity to 3 out of the 4 non-ortho PCBs.

slide23

The assay demonstrates virtually no reactivity to other PCBs, PCDDs or PCDFs, providing a rapid and specific method for the mass screening of environmental samples, prior to confirmatory analysis of high concentration samples.

slide24

The final Oral presentation is by Engwall and colleagues, and reports their findings from an international intercalibration study of dioxin-like compounds in cod liver using bioassays.

slide25

Intercalibration studies are one of the most effective methods for evaluating the accuracy of methods, in this case covering a number of different bioassay methods.

slide26

The study showed that a good percentage of the participating laboratories gave values within 60-106% of the ‘true’ value, indicating a good degree of accuracy and showing good agreement with chemical analysis by HRGC-HRMS.

slide27

The authors also point at possible problems with interfering compounds that can elevate the determined TEQ, and also suggest work to be performed to reduce the risk of false negatives.

slide28

A large amount of the presented work in the session looks into the application of various immunoassay and bioassay methods as a tool for the rapid screening of samples for PCDD/Fs and PCBs.

slide29

The methods work for a variety of different matrices, for example human blood (Usuki), flyash(Miyata, Matsuyama), PCB oil (Takigami) environmental samples (Fujihara, Kobayashi).

slide30

Most of the methods employ some specific clean-up practices to remove compounds such as PAHs, and other Ah antagonists, which can result in high determined values when compared with HRGC-HRMS methods or reference values.

slide31

In contrast the work of Nording and colleagues focuses on the bio-analysis of PAHs in soils, and has produced a method recommended for semi-quantitative analysis of PAHs.

slide32

The method is far simpler to implement in the field and the authors view is that this far outweighs the lower accuracy as a tool for rapid field screening.

slide33

Ikeda and colleagues present some work complementary to that presented by Rivera, where Blue Mussels are utilized as bio markers to monitor the levels of pollution across a wide range of estuaries, beaches, canals and offshore.

slide34
High levels detected in Blue Mussels corresponded well with areas known to be affected by high discharges of PCDD/F’s.
slide35

C.S. NG and W.C. Chung have taken a slightly different approach to speeding up analysis by producing a simplified extraction and clean-up method for application in foodstuff samples.

slide36
Given the relatively complex nature of foodstuff samples, the determined concentrations and good recoveries presented
slide37

an effective method has been produced which accounting for the 1-2 days saved during clean-up could increase sample turnover and reduce turnaround times significantly.

slide38

An instrumental approach to screening has been taken by Worrall and colleagues, with the development of a GC-MS/MS method, allowing profiles of congeners to be detected and reported, giving the possibility of the ‘finger-print’ of a source to determined.

slide39
Borgen and colleagues have developed a method in which a number of challenges due to the complexity of the analytes needed to be overcome.
slide40

Screening a number of areas in the south of Norway for chlorinated paraffin’s, compounds for which there are several thousand components in a single commercial mixture.

slide41
Analysis by electron capture negative-ion ionisation gives greater selectivity allowing a survey to be conducted.