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Last changed: 24/09/2003
Concerning the unequivocal identification of polymers the following general procedure for the documentation of polymers has been decided by the KBwS:
According to KBwS decision of the 1st meeting 2003 the WGK classification of polymers based on data of the monomers may be acceptable in particular cases. In order to classify polymers based on data of the monomers the classifier has to meet the following requirements:
The Office of Commission for the Evaluation of Substances Hazardous to Waters will decide on requests in unambiguous cases, whereas all other cases will be decided by the KBwS.
The documentation of substances without indicating a CAS-No. is only acceptable for substances, which are excluded from the liability of registration according to § 5 German Chemicals Act. For the documentation of substances, for which no CAS-registration number is available, the following information is required:
Food and feeding stuff is classified as non-hazardous to water (nwg) according to No. 1.2 d) and e) VwVwS from 17.05.1999, unless listed in Annex 2. In cases, where food stuff is employed as a technical product, no. 1.2 d) and e) of General Administrative Regulation on the Classification of Substances hazardous to waters (Verwaltungsvorschrift wassergefährdende Stoffe - VwVwS) of May 17th, 1999 are not effective. In this case, the substance has to be classified according to Annex 3 VwVwS.
A mixture/preparation form can be downloaded, which represents a recommendation for the documentation of mixtures/preparations at the enforcement authorities. In addition, a float chart for the determination of the WGK of mixtures is available (pdf.file).
Please note:
The classification of mixtures is the responsibility of the manufacturer
or distributor. There are no provisions for centralized collection
and publication of the classifications. It is recommended, however,
that classifiers maintain a documentation (on the safety data sheet,
if possible), to enable operators of facilities to prove their adherence
to the guidelines in a water licensing procedure.
A WGK classification on the basis of an analogy to another substance is in general not provided for, according to No. 3 of VwVwS, however, may be acceptable for:
Ionic compounds provided that the anion and the cation are already classified by means of separate substance classifications (reference substance), whereby the highest WGK is mandatory and the water solubility of the reference substances must not differ considerably from the water solubility of the classified substance. An extrapolation from an acid/base to the salt is allowed, but not vice versa (i.e. an analogue classification from phenylate to phenol is allowed, but not from phenol to phenylate).
Substances, which transform completely and rapidly (in particular through hydrolysis), if the half-life under environmental conditions (i.e. determined according to OECD 111) is below 4 hours and the transformation products are classified into WGK, whereas the highest WGK is mandatory.
Analogue classifications, which are in accordance with the above mentioned prerequisites, should be submitted to the Bureau of Documentation and Information on Substances hazardous to waters.
All other analogue classifications, which are solely based on similar structure characteristics, have to be discussed at the Commission for the Evaluation of Substances hazardous to waters (KBwS).