Inherently biodegradable

Upper LEVEL 1 Chronic toxicity Toxicity in soil and plants Additional mutagenicity Long-term toxicity Bioaccumulation Inherent biodegradability Additional abiotic degradability 100 t/annum or 500 t cumulative... 

The categorization as inherently biodegradable together with the values and other physical properties enabled estimates of biodegradation half-lives in water, soil, and sediment to be made by BUSES. Those for soil and sediment were then reduced to be more consistent with the results of Terytze et al. (2000), as shown in Table 8. 

Inherent biodegradability is applied when the compound may be degraded, though not under the standard conditions generally used their degradation may require, for example, preexposure to the xenobiotic. 

Table 1 also indicates that some FMs, including the PCMs and NMs, do not pass ready or inherent biodegradation tests. However, this does not mean that these FMs do not undergo biotransformation to polar metabolites under realistic conditions. These realistic biodegradation tests may be conducted in vitro, in bench-top die-away studies, or as continuous activated sludge and porous pot tests. Ideally, the conditions should include (1) realistic FM concentrations... 

In the Simonich et al. [11] study, the concentration of 16 FMs in final effluent ranged from 0.001-7.6 pg/L in the U.S. to 0.01-4.6 pg/L in Europe (see Table 5). In addition, terpineol no longer dominated the relative FM profile in final effluent, except for final effluent collected from two European trickling filter plants (see Fig. 7) [11]. As the figure indicates, nonbiodegradable and inherently biodegradable, sorptive FMs dominated the relative FM profile in final effluent (including HHCB, AHTN, OTNE, and acetyl cedrene). 

OECD Guideline for testing of chemicals, Inherent biodegradability modified Zahn-Wellens-test 302B cited in Ref [300, 300a]... 

Investigation of the pronounced resistance of ABS to microbial degradation demonstrated that the branched alkyl chain derived from tetrapropylene was responsible for the longevity of ABS in the aquatic environment [74], Shortly after this discovery, the surfactant industry reacted and made attempts—in some countries additionally forced by legal restrictions—to provide an alternative surfactant with comparable functional properties, but with inherent biodegradability. The outcome was the introduction of LAS on the detergent market. After the switch from ABS to LAS in almost all nations in the mid 1960s, a substantial drop in the levels of ABS was observed [8],... 

To sum up, the living character of the aluminum alkoxide mediated ROP of lactones has permitted the synthesis of novel ABA triblock copolymers, the composition and molecular weight of which can purposely be tuned up for displaying excellent elastomeric properties. Interestingly, the inherent biodegradability of each partner, PCL and PDXO, would open up new applications for these novel thermoplastic elastomers. 

Table 9.1 Biodegradability (in %) of selected pharmaceuticals from various classes in different OECD tests (Kiimmerer and co-workers, unpublished work) [46, 99, 106, 110]. Criterion for ready biodegradability in 301 tests and inherent biodegradability in 302 tests is > 60%.

Table 16.2 Proposed scheme for using ready or inherent biodegradation test data to assign half-lives or rate constants for use in screening-level chemical assessment or modeling [16].

US Environmental Protection Agency (2000) Interim Guidance for Using Ready and Inherent Biodegradability Tests to... 

Also, in the context of this book, it is worth noting that many products derived from renewable resources will be inherently biodegradable and therefore, adhere to principle 10. 

Starch has been considered an attractive raw material for polymer applications for almost 200 years. Kirchoff s discovery in 1811 that treatment of starch with an acid yields a sweet substance was an unexpected result of the search for a low-cost substitute for natural rubber.1 Considerable research in the development of starch-based polymer materials has been stimulated by the facts that starch is produced from wide variety of sources, is an annually renewable resource and is inherently biodegradable. 

Starch offers several potential advantages as a raw material for plastics applications. It is annually renewable, obtained from a variety of plant sources and is a low-cost material. Interest in its use in biodegradable plastics is also driven by the inherent biodegradability of starch and the ubiquity of microorganisms capable of utilizing starch as a carbon source. 

The inherent biodegradability tests concerned are the Zahn Wellens test (OECD TG 302 B) and the MITIII test (OECD TG 302 C). The conditions for use in this regard are ... 

Tests for inherent biodegradability are designed to assess whether a substance has any... 

The basic test conditions favouring an assessment of the inherent biodegradation potential... 

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