Techniques and methods were discussed for improving bioaccumulation assessments [e.g., reducing animal testing, tiered approaches for bioaccumulation assessment, potential revision of the existing in vivo OECD TG 305 bioconcentration test (OECD 1996)], and how new methods could be efficiently developed in time to support the Canadian and the EU agencies in their evaluation of potential PBTs.
Therefore, a more precautionary approach to the LoC concept would be to use the results (exceedances and non-exceedances of the LoCs) from all test tiers to inform the risk characterisation and to conclude whether the observed effects tested in the different tiers fall below or above the set of ({text{LoC}}_{text{EU-wide}}^{text{n}}) relevant for the respective protection goal (Fig. 5).
In this context, EFSA refers to 'tiered testing', with tier 1a and 1b referring to in vitro or in planta laboratory tests, while tier 2 refers to semi-field tests (i.e. outdoor tests with some containment) and tier 3 to field tests [3].
Thus, the effect testing at tier 1 comprises two different levels of complexity.
Furthermore, testing at tier 2 will also consider environmental behaviour of ENMs altered in the test system.
The experimental fate testing at tier 2 will also need data from modified or even newly developed test guidelines and guidances.
Pricing starts at $499 per test cycle, with three tiers of testing: Bronze, Silver and Gold.
Neutralization efficiency of the patients' plasma was tested against tier 2 pseudoviruses (3 clade C - ZM53, Du172.17 and Du156.12 and 3 clade B - RHPA4259.7, TRO.11 and SC422661.8) obtained from NIH AIDS Research and Reference Reagent Program by TZM-bl assay.
The LHT and associated SOP provide a reliable second tier in a three-tiered testing process, in which the first tier is a suspension test and the final tier is a field test.
SRT found 3 nominally significant pathways using tier one criterion, but none passed the multiple testing correction using tier two criterion (Table 3).
