TBT agreement

Thus, in the language of the new TBT agreement, when a government acts to accept a voluntary standard to make it mandatory, the resulting document is a technical regulation. A measure used to ascertain compliance with a standard or technical regulation is a conformity assessment procedure. 

In order to harmonize SPS measures on as wide a basis as possible, the SPS agreement encourages members to base their SPS measures on international standards, guidelines, or recommendations. Thus, the SPS agreement, like the new TBT agreement, encourages use of international standards. The SPS agreement refers specifically to standards established by the Codex Alimen-tarius Commission, as discussed below. 

Stedeford, T, and Persad, A. S. (2007). The influence of carcinogenicity classification and mode of action characterization on distinguishing like products under Article III 4 of the GATT and Article 2.1 of the TBT agreement. N.Y.U. Environ Law J 15, 377-419. 

The WTO Agreement on the Application of Sanitary and Phytosanitary Measures (WTO-SPS, 1994) and the Agreement on Technical Barriers to Trade (WTO-TBT, 1994) recognise as the international standards, guidelines and... 

A mussel material stored at — 20°C was found to maintain stable butyl tin contents (as verified over 44 months) however, even this low temperature could not stabilise phenyltin compounds which, therefore, could not be certified although the between-laboratory agreement obtained during the certification campaign was found to be reasonably good (Quevauviller et al., 1997b). The mussel material, CRM 477, was certified for monobutyltin (MBT), DBT and TBT (Table 6.1). 

ICP-MS is another means of detection that has been used for the determinations of tin compounds following HPLC separation. Two different types of plasma torch were assessed for the analysis of alkyltin species (Branch et al., 1989) An experimental low flow torch yielded better limits of detection than the standard torch. The limit of detection of TBT using the standard torch was 1.6 ng (as tin), an improvement of several orders of magnitude over an HPLC-AAS coupling. Results of analyses of spiked water samples by this method and by the HPLC-AAS method were in satisfactory agreement. 

NAFTA also contains TBT and SPS agreements similar to those in the new WTO agreements. 

Table 3.6.3 Biological-effect assessment criteria for TBT prepared and agreed during the technical TBT workshop, 6-7 November 2003, The Hague. Assessment criteria for imposex in Nucella lapillus are presented alongside equivalent VDSI/ISI values for sympatric populations of other relevant species (OSPAR agreement 2004-15 www.ospar.org)... 

Tri-n-butyltin bromide (TBT), triethyltin bromide (TET), and trimethyltin chloride (TMT) inhibited the cardiac SR Ca uptake (Figure 4.1.2) and Ca +-ATPase (Figure 4.1.3) in vitro in rat heart in a concentration-dependent manner. The order of potency for Ca +-ATPase as determined by IC50, is TBT (2 pM) > TET (63 pM) > TMT (280 pM). For Ca uptake, it followed the same order, i.e., TBT (0.35 pM) > TET (10 pM) > TMT (440 pM). In agreement with them vifro results, both cardiac SR Ca +-ATPase and Ca uptake were significantly inhibited in vivo in rats treated with these organotin compounds... 

The reliability was tested by analyzing a certified marine sediment reference material CRM 462. The TBT and DBT concentrations found were in good agreement with the certified values. The MBT concentration was not certified in that sediment. 

In fact, treatment of 1 with an excess of Li powder in THF at r.t. leads to the formation of TBTS-Li (2) which can be isolated after crystallization from hot pentane as a red-orange crystalline material containing four molecules of THF (yield 76 %). The donor-free silyl potassium compound TBTS-K (2) was obtained nearly quantitatively by heating a solution of 1 in heptane in the presence of an excess of Na-K alloy. Although attempts to obtain single crystals of 2 suitable for an X-ray structure analysis failed, the structure proposed was in fiiU agreement with the MS and NMR data, and especially the Si NMR data. 

The kinetic data show that there is a reasonably good agreement between experimental points and the ones calculated by Equation (22). The values of activation energy obtained for the uncatalyzed (A uc) and catalyzed (AEJ reaction of behenic add with decanol, lauryl alcohol, myristyl alcohol and cetyl alcohol are shown in Table 2.The model Equation (22) is also appropriate for the reaction of erudc acid with cetyl alcohol and oleyl alcohol using TBT as a catalyst (Tiwari Sawant, 2005). 

The accuracy of this type of simultaneous spedes-spedfic multi-element GC-ICP-IDMS determination of five elemental species of high relevance for toxicological assessment of marine food samples was demonstrated by the excellent agreement of the results obtained with the corresponding certified values for different reference materials. LCDs of 1.4 ng g for MMM, 0.06 ng g for TML, 1.2 ng g for DBT, and 0.3 ng g for MBT and TBT were obtained, which are much lower than the limits required for adequate control of seafood. The tolerable weekly intake of MMM for humans as recommended by the US Environmental Protection Agency (EPA) is <0.7 Jg kg body weight and the tolerable MMM content in fish as recommended by the EU is < 1 xg g . With resped to the relative simple sample preparation and the commerdal availability of certified spike solutions of MMM and the butyltin compounds, multi-spedes spedes-spedfic GC-ICP-IDMS has a high... 

In this case, the spike added first is used as a tracer, for example, in metabolic studies, and the second for quantification of the elemental species. Meija et al. [99] investigated the redox interconversion reaction between Cr(III) and Cr(VI) in yeast using °Cr-emiched Cr(III) and Cr-enriched Cr(VI) by least-squares ion intensity-based IPD. They found that the results were in exact agreement with conventional isotope dilution calculations. An example in which IPD was applied for metabolism studies is the determination of the metabolism of butyltin compounds in rats [100]. Sn-labeled MET, Sn-labeled DBT, and Sn-labeled TBT dissolved in tap water were administered orally to the animals. Degradation of the butyltin compounds was studied in different organs by least-squares IPD and their concentrations were determined via reverse isotope dilution analysis using the corresponding compounds of natural isotopic composition as spikes. 

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