# EU 'One Substance, One Assessment' (OSOA) package enters into force, impacting RoHS scientific/technical tasking arrangements

**EU RoHS (Directive 2011/65/EU)**  
**European Commission (DG Environment)**  
**Announced**  
**Jan 5, 2026**  
**Implementation**  
**Jan 1, 2026**

## Description

The European Commission announced that the EU 'One Substance, One Assessment' (OSOA) package entered into force on 1 January 2026. While horizontal in nature, OSOA is relevant to RoHS because it changes governance and how scientific/technical work that underpins chemicals legislation is organised (including re-attribution of certain technical tasks to ECHA and creation of a common chemicals data platform). Compliance teams should monitor downstream impacts on RoHS restriction/exemption assessment workflows, evidence expectations, and process/timeline changes as OSOA implementation progresses.

## Sources

- Official [New rules to streamline EU chemical assessments enter into force](https://environment.ec.europa.eu/news/new-rules-streamlining-chemical-assessments-enter-force-2026-01-05_en)
- Official [RoHS Directive - Environment - European Commission](https://environment.ec.europa.eu/topics/waste-and-recycling/rohs-directive_en)