Checks on more than 3,800 REACH dossiers have found that 32% for substances at tonnage levels of 1,000tpa and above were found to be non-compliant.
The REACH Compliance project, a joint effort between Germany's Federal Institute for Risk Assessment (BfR) and the Environment Agency (UBA), also found the rate of non-compliance for substances at 100-1,000tpa was 19%.
BfR noted that for about 37% of the total dossiers a conclusion could not be reached due to issues with evaluation methodology.
The project began in 2014 and was discussed at a BfR workshop on data quality in registration dossiers on 23-24 August, with conclusions released at the beginning of October.
The workshop aimed to inform stakeholders about the dossier quality of the majority of registrations for high tonnage substances and to facilitate dialogue between industry and regulators on how it can be improved.
The results contrasted with conclusions from an Echa evaluation progress report from March. The agency found that in checks on dossiers from 2008 to the end of last year 69% of 1,350 in the 1,000tpa> band were non-compliant. Meanwhile, 77% in the 100-1,000 tonnage band it checked contained data gaps.
The project investigated the availability of human health and environmental data in REACH registrations and how it complied with requirements on toxicological and ecotoxicological information as laid down in the Regulation.
By checking the available information on selected endpoints in a high number of dossiers, the institute added, the project provides a "representative outcome" on dossier quality.
An average of 70% of registrants, it found, commonly used the option to deviate from standard testing requirements and provide justifications for this.
"The outcome of the project indicates that increased efforts by industry and authorities are needed to achieve a higher rate of compliance for the chemical dossiers," BfR said.
At the workshop, Echa introduced its strategy for improving dossier quality following the final REACH registration deadline on 31 May.
BfR’s work is expected to feed into the agency’s plans. A combined approach concerning identified concerns on risks for humans and the environment will mean dossier evaluation procedures will be "optimised", it said.
Measures to encourage the updating and improving of dossiers, including the chemical safety report, are under consideration, the institute added.
This story was amended on 16 October to clarify the percentage of non-compliance