Styrene

Bioaccumulation: aquatic / sediment

Link to relevant study record(s)

Reference

Endpoint:

bioaccumulation in aquatic species, other

Type of information:

other: review data

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Qualifier:

no guideline followed

Principles of method if other than guideline:

A mean log value based on different studies has been caculated. By using the Kow value and the equation for BCF from the TGD a BCF is derived.

GLP compliance:

no

Radiolabelling:

not specified

Vehicle:

not specified

Test organisms (species):

other: calculated from log Kow

Route of exposure:

other: calculated BCF

Test type:

other: calculated BCF

Water / sediment media type:

not specified

Nominal and measured concentrations:

calculated BCF from different studies

Reference substance (positive control):

not required

Details on estimation of bioconcentration:

A mean log value based on different studies has been caculated. By using the Kow value and the equation for BCF from the TGD a BCF is derived.

Type:

BCF

Value:

74

Basis:

other: not specified

Calculation basis:

other: Kow value and the equation for BCF from the TGD were used to derive the BCF

Remarks on result:

other: calculated

An experimental study which indicated that styrene did not bioconcentrate to the levels expected from its Kow value is not considered valid. However, no further testing is required for the risk assessment as available data from other substances are sufficient for this purpose. In the risk assessment a bioconcentration factor of 74 is used, as predicted from the partition coefficient. To derive this BCF three measured values for the octanol-water partition coefficient (as log Kow) were used, these are 2.95 (Hansch and Leo, 1979), 2.96 (BASF, 1987) and 3.16 (Banerjee et al., 1980). The mean log value from these studies has been used in the environmental modelling in this risk assessment (this is equivalent to taking the geometric mean of the actual measurements). This gives a value of 3.02. On the basis of the balance of the information available it is concluded that styrene will not accumulate in aquatic organisms and that R53 is therefore not appropriate. The Commission

working group on the Classification and Labelling of Dangerous Substances at their meeting on 15-17 September 1999, agreed not to classify styrene for environmental effects.

Validity criteria fulfilled:

not applicable

Executive summary:

Styrene was tested for bioaccumulation. The BCF was determined to be 74.

Description of key information

Significant accumulation in organisms is not to be expected
The value for log n-octanol-water partition coefficient (log Kow), which is considered a good predictor for bioconcentration, is approximately three. Since an experimental study showing low bioaccumulation of styrene is considered not valid, the BCF was predicted using log Kow and the equation from the TGD, giving a value of 74. 

Key value for chemical safety assessment

BCF (aquatic species):

74 dimensionless

Additional information

A QSAR was performed as well using the BCF baseline. The BCF was predicted to be between 1.714 and 2.016 l/kg. These values suggests that the compound probably does not accumulate appreciably in aquatic organisms. Moreover, because styrene is probably metabolized and excreted, bioaccumulation is unlikely. This is also supported by the fact that analogue substances, such as toluene, xylene and ethylbenzene do not accumulate to any great degree in aquatic organisms.