Sulphuric acid, compound with graphite

Biodegradation in water: screening tests

Description of key information

The biodegradation is defined as the biologically mediated degradation or transformation of chemicals usually carried out by microorganisms. (Guidance on information requirements and chemical safety assessment - Chapter R.7b: Endpoint specific guidance)
According to column 2 of Annex VII (standard information requirements for substances manufactured or imported in quantities of 1 tonne or more) of Regulation (EC) No 1907/2006 the study does not need to be conducted if the substance is inorganic.
Sulphuric acid, compound with graphite is an inorganic solid, consisting of natural graphite and variable amounts of intercalated sulphuric acid.
Graphite is a naturally occurring solid substance which is insoluble in water. Due to its physico-chemical properties it is not systemically and biologically available and does not cross biological membranes. In the aquatic compartment it can be considered as an inert substance.
Biologically mediated degradation or transformation of graphite carried out by microorganisms is therefore unlikely to occur. 
The intercalated sulphuric acid is partially leached out by water and dissociated into the environmentally ubiquitous sulphate and hydronium ions. In anaerobic environments sulphate is biologically reduced to (hydrogen) sulphide by sulphate-reducing bacteria, or incorporated into living organisms as source of sulphur, and thereby included in the biological sulphur cycle. Some sulphates may also be precipitated in form of naturally occurring minerals. 
Since the components of sulphuric acid, compound with graphite are inorganic substances, a study to determine the biodegradation in water is not required under Regulation (EC) No 1907/2006 (REACH).