German Environment Agency classifies solid polymers in water hazard class 1

The German Environment Agency (Umweltbundesamt) has classified the group of substances consisting of solid, non-dispersed polymers with a water solubility of less than 100 mg/l and an average molar mass of more than 1000 g/mol under the identification number 11667 into water hazard class (WGK) 1. The general decree of August 31, 2026, was published on Friday, October 2, 2026, in the Federal Gazette (Bundesanzeiger) under the official reference BAnz AT 02.10.2026 B4. Simultaneously, the authority ordered the immediate execution of the classification.

Ex officio classification according to the AwSV

The basis for the decision is Section 6(2) of the Ordinance on Facilities for Handling Substances Hazardous to Water (AwSV), which grants the German Environment Agency the authority to decide ex officio on the classification of substances and substance groups. Pursuant to Section 6(4) sentence 1 AwSV, these decisions are announced publicly in the Federal Gazette; the notification obligations under Section 7(2) AwSV remain unaffected. The authority evaluated the substance group on its own initiative and not upon the application of third parties.

The classification includes a footnote with conditions for free residual monomers:

• The total content of free residual monomers without a published WGK classification or with a classification in WGK 3 is below 0.2%.
• The total content of free residual monomers with a classification in WGK 2 is below 5%.
• The polymers do not require classification and labeling with hazard statements that would necessitate an assignment of more than 4 evaluation points according to Annex 1 No. 4.2 AwSV.

Evaluation bases and data situation

The decision is based on two testing areas. Regarding mammalian toxicity, the acute oral LD50 is above 2,000 mg/kg body weight, from which no hazard statements are derived. Regarding environmental hazard, the acute aquatic toxicity with LC/EC50 above 100 mg/l results in two precautionary and evaluation points.

No data were available for two further testing points:

• Proof of ready biodegradability
• Proof to exclude bioaccumulation potential

Following the announcement in the Federal Gazette, the classification decision is additionally searchable via the website https://webrigoletto.uba.de/rigoletto/.

Immediate execution and legal remedies

Immediate execution was ordered in accordance with Section 80(2) sentence 1 number 4 of the Code of Administrative Court Procedure (VwGO). In its justification, the German Environment Agency refers to the public interest: the classification has a direct effect on the construction and operation of facilities requiring a permit and, according to Section 1(1) AwSV, serves to protect water bodies from adverse changes in their properties. A legal remedy and possible litigation process could drag on for several years, meaning that the effective protection of the legal assets would not be guaranteed without immediate execution.

Due to the order, an objection or a lawsuit against the general decree shall have no suspensive effect. The decree becomes effective upon notification, which occurs on the 15th day after publication in the Bundesanzeiger (Federal Gazette), based on Section 41 Paragraph 4 Sentence 3 of the Administrative Procedure Act. An objection may be lodged within one month after notification with the Umweltbundesamt (Federal Environment Agency) located in Dessau-Roßlau. The decree is signed on behalf of Süßmilch.

Significance for Operators and Industry

For operators of plants handling water-hazardous substances and for the chemical industry, the classification into WGK 1 represents a new, immediately effective classification of a broad polymer group that was previously not subject to any published WGK classification. Since immediate execution has been ordered, plant operators must take the classification into account even before a legally binding decision on possible legal remedies has been reached. The footnote conditions regarding free residual monomers simultaneously define the limits within which the classification into WGK 1 applies.

Source: Bundesanzeiger, BAnz AT 02.10.2026 B4, Announcement of the Federal Environment Agency dated August 31, 2026 (official reference: BAnz AT 02.10.2026 B4).