Registration Dossier

Administrative data

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:
PNEC aqua (freshwater)
PNEC value:
0.73 mg/L
Assessment factor:
10
Extrapolation method:
assessment factor
PNEC freshwater (intermittent releases):
0.73 mg/L

Marine water

Hazard assessment conclusion:
PNEC aqua (marine water)
PNEC value:
0.73 mg/L
Assessment factor:
10
Extrapolation method:
assessment factor

STP

Hazard assessment conclusion:
PNEC STP
PNEC value:
89.5 mg/L
Assessment factor:
1
Extrapolation method:
assessment factor

Sediment (freshwater)

Hazard assessment conclusion:
PNEC sediment (freshwater)
PNEC value:
3.6 mg/kg sediment dw
Extrapolation method:
equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:
PNEC sediment (marine water)
PNEC value:
3.6 mg/kg sediment dw
Extrapolation method:
equilibrium partitioning method

Hazard for air

Air

Hazard assessment conclusion:
no hazard identified

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:
PNEC soil
PNEC value:
0.26 mg/kg soil dw
Extrapolation method:
equilibrium partitioning method

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:
no potential for bioaccumulation

Additional information

Methacrylic anhydride, like other anhydrides of organic acids, hydrolyses in an aqueous environment with a half-life in the order of minutes resulting in two molecules of methacrylic acid per molecule methacrylic anhydride. As a consequence, instead of performing new studies, methacrylic acid studies have been used in many places of the assessment to describe the effects of methacrylic anhydride. For the purpose of PNEC derivation the no-effect-levels of methacrylic acid have been divided by 1.117 (corrected for molecular weight difference between two molecules methacrylic acid vs. one molecule methacrylic anhydride).

For methacrylic acid there are chronic data available for the three standard trophic leves plus additional data in marine species. The NOEC of 8.2 mg/L in algae has been carried forward for the risk assessment. The ecotoxicity data of methacrylic acid in marine species do not indicate higher sensitivity of marine life.

Conclusion on classification

No environmental classification is required.