Threshold value for bisphenol A retained / new data on N-Octyl tin compounds
The Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has presented the 2010 list of MAK and BAT values containing new data on 61 substances. These values for the classification of health hazards constituted by work area substances have been adjusted this year. Thus the Commission is using a new conversion process similar to that used at a European level (REACH) in the event that a MAK value is derived from animal experiments based upon the oral ingestion of substances. The categories that describe whether substances can cause cancer have been more clearly defined by the Commission. Substances within categories 1 to 4 bear no increased cancer risk if the MAK value is observed; category 5 lists substances that only represent a slight cancer risk if the MAK value is observed. This is particularly assessed in comparison with other influences, such as the endogenic concentration of a substance in the body. As is the case with all substances, the Commission has formulated a detailed scientific explanatory statement for each classification.
The MAK and BAT values list was presented to the Federal Ministry for Labour and Social Affairs as every year. It contains the MAK values indicating the amount of a substance - be it in the form of gas, steam or aerosol in the air at the workplace - that will not cause long-term damage. Additionally, the list indicates whether these substances are carcinogenic, can damage germ cells or a child during pregnancy, can sensitise the skin or the respiratory tract or are percutaneously absorbable. Apart from the MAK values, the list also indicates the concentration of a substance in the body to which a person can be exposed for the duration of their working life without their health being damaged (BAT values). The biological guideline values (BLW/BAR values) are also described. Compiling this list of MAK and BAT values is part of the DFG's mission to provide policy advice to public authorities on questions relating to science and research, as laid down in its statutes. It is important here to emphasise that the Senate Commission is an independent body, whose work is based purely on scientific findings and transparent decision-making processes.
In the current MAK list, two of the substances that have new and in this case lower values for non-toxic concentration in the air at the workplace are the heavy metals mercury and manganese, together with their anorganic compounds. Mercury and its compounds were again classified as skin sensitising. New data, supplemented during the commentary period, also facilitate a differentiated evaluation of the effect of n-octyl tin compounds during pregnancy. These compounds are used as stabilisers in PVC. Furthermore, the Commission carried out a further review of bisphenol A. This substance, used for example as a plasticiser in baby bottles and PET bottles, has been investigated for its effects on reproduction and retains its MAK value, valid from 1996, which indicates no risk during pregnancy.
Fresh scientific data may be submitted until December 30, 2010 in order to comment upon the justifications for all new entries and modifications in the 2010 MAK and BAT values list. Only then will the Senate Commission conclusively adopt the recommended values and their justifications as the basis for legislation on health protection at the workplace.