Limit Values Germany - AGW

The German Committee on Hazardous Substances (Ausschuss für Gefahrstoffe – AGS) is an advisory body of the Federal Ministry of Labour and Social Affairs, concerned with occupational safety and health measures. Its members represent inter alia workforce, employers, enforcing authorities, institutions for statutory accident insurance and prevention for trade and industry (BGs), and academic science.

The AGS is assisted by three subcommittees: Hazard Management, Protection Measures, and Risk Assessment. An additional “Occupational Medicine” subcommittee supports not only the AGS but also the Committee for Biological Agents (ABAS).

The “Risk Assessment” subcommittee deals with the classification of genotoxic, carcinogenic and reprotoxic substances, and recommends Occupational Limit Values (Arbeitsplatzgrenzwerte – AGW) to the AGS. According to the German Hazardous Substances Ordinance (Gefahrstoffverordnung) an AGW is a time-weighted average concentration in the workplace air, referring to a given period of time. The AGW states the concentration of a substance below which acute or chronic adverse health effects are not generally expected. AGWs are thus based exclusively on available occupational medical experience and toxicological findings.

As a rule, the “Risk Assessment” subcommittee evaluates OEL proposals elaborated by other organisations, predominantly by the “MAK Commission”, and examines whether or not they are compatible with the AGW definition. Other sources are foreign OELs and EU indicative occupational exposure limit values with the associated relevant criteria documents, or internal industry limit values. Should the scientific data basis be limited, the subcommittee itself may derive AGWs as health-based occupational exposure limits using certain extrapolation factors 1, 2, providing there is no indication of genotoxicity or carcinogenicity.

The subcommittee’s AGW recommendations must be adopted by the AGS plenum before being published on behalf of the Federal Minister of Labour and Social Affairs in the Joint Ministerial Gazette (Gemeinsames Ministerialblatt) and in the Federal Gazette (Bundesanzeiger).

The German AGWs are listed in Technical Rule for Hazardous Substances (TRGS) No. 900. Under German legislation, an employer proceeds on the assumption that the requirements of the Hazardous Substances Ordinance are fulfilled whenever he or she applies the Technical Rules. The criteria documents of the AGWs which were directly derived by the AGS are published (in German) on the website of the Federal Institute for Occupational Safety and Health (BAuA).

Risk-based limit values for carcinogenic substances

In view of the fact that health-based workplace exposure limits cannot currently be derived for the vast majority of carcinogenic substances, the AGS Committee for Hazardous Substances recently proposed a generic concept for the setting of risk-based limit values for carcinogenic substances in the context of social policy. The following limits for occupational exposure-related lifetime cancer risks were adopted:

Acceptable risk:
Interim limit: 4 : 10.000
As of no later than 2018: 4 : 100.000

Below these limits, a risk is accepted. Above these limits, a risk will be tolerated if the measures specified in a corresponding catalogue are complied with. The second risk limit is the:

"Tolerable Risk" of: 4 : 1.000

This risk may not be exceeded.

The risks refer to a working lifetime of 40 years and continuous exposure every working day. Substance-specific concentrations derived from well-founded exposure-risk models are compiled in TRGS 910 and should be taken into account by employers during the performance of risk assessments. During a testing phase which is to last several years and is expected to end in 2015, the risk limits and the respective substance concentrations in the workplace air will not be regarded as legally binding limit values under the German Hazardous Substances Ordinance.

June 2010

References

1 Kalberlah, F.; Föst, U.; Schneider, K.: Time extrapolation and interspecies extrapolation for locally acting substances in case of limited toxicological data. Ann Occup Hyg 46 (2002) 175-185

2 Schuhmacher-Wolz, U.; Hassauer, M.; Kalberlah, F.: Provisional occupational exposure limits for reproductive toxicants. Bremerhaven: Wirtschaftsverlag NW 2006. ISBN: 3-86509-572-0; 978-3-86509-572-5