Registration Dossier

Administrative data

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:
PNEC aqua (freshwater)
PNEC value:
0.004 mg/L
Assessment factor:
1 000
Extrapolation method:
assessment factor
PNEC freshwater (intermittent releases):
0.045 mg/L

Marine water

Hazard assessment conclusion:
PNEC aqua (marine water)
PNEC value:
0 mg/L
Assessment factor:
10 000
Extrapolation method:
assessment factor

STP

Hazard assessment conclusion:
PNEC STP
PNEC value:
10 mg/L
Assessment factor:
100
Extrapolation method:
assessment factor

Sediment (freshwater)

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

Sediment (marine water)

Hazard assessment conclusion:
PNEC sediment (marine water)
PNEC value:
0.002 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:
0.001 mg/kg soil dw
Extrapolation method:
equilibrium partitioning method

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:
no potential for bioaccumulation

Additional information

Due to the rapid hydrolysis of the parent compound, the PNEC derivation is based on the results for the parent compound, its hydrolysis product methanol (CAS 67-56-1) and its hydrolysate (3 -d hydrolysis).

Effect values of the hydrolysis product HCl (7647 -01 -0) were not considered in the ecotoxicological evaluation of the substance since the observed toxicity was not due to intrinsic properties of the molecule, but is due to pH effects.

Conclusion on classification

The parent compound methyl chloroformate (CAS 79-22-1) rapidly hydrolyses in contact with water and forms methanol (CAS 67-56-1), HCl (CAS 7647-01-0) and CO2 (CAS .124 -38 -9)

Data from HCl have not been taken into consideration as observed effects are caused by a pH-shift in the test medium. Data for the parent compound itself are available only for short-term toxicity to fish. Acute toxicitty data for the hydrolysis product methanol are available for three trophic levels: fish, aquatic invertebrates and algae; chronic toxicity data are only available for algae.

Therefore, the conclusion on classification will be based on the information available for methyl chloroformate and its hydrolysis product methanol.

Official classification regarding environmental hazards:

Aquatic compartment

According to Regulation (EC) No 1272/2008 Annex VI Table 3.1 the substance holds no relevant classification.

According to Regulation (EC) No. 1272/2008 Annex VI Table 3.2 the substance holds no relevant classification.

  

Self-classification

Aquatic compartment

Following GHS, the substance is not to be classified as acutely or chronically hazardous to the aquatic environment.

Rationale:

The substance is not to be classified as acutely hazardous to the aquatic environment, since the lowest acute effect value is > 1 mg/L.

Chronic data are available for algae; therefore, classification is based on the available chronic and acute toxicity data.

- Chronic toxicity data:

Chronic data are available for algae (Scenedesmus quadricauda, 8 -d TT (ErC50) = 8000 mg/L; Bringmann and Kuehn, 1978), indicating that the substance does not present a long-term hazard according to the categories outlined in Table 4.1.0(b) (ii) (Commission Regulation (EU) No 286/2011 amending Regulation (EC) No 1272/2008) for rapidly degradable substances. Based on the chronic data for the hydrolysis product methanol, the parent compound is not to be classified as chronically hazardous to the aquatic environment as the lowest chronic effect value is clearly higher than 1 mg/L

- Acute toxicity data:

The lowest effect value(LC/EC50) for acute toxicity to aquatic organisms (fish and aquatic invertebrates) is >1 and . 10 mg/L.

However, the parent compound methyl chloroformate hydrolyses to form methanol. The hydrolysis product methanol is readily biodegradable (Price et al., 1974). Log Kow values of methyl chloroformate and its hydrolysis product methyl are <4. Therefore, based on the available data for the hydrolysis product methanol and for the parent compound itself, methyl chloroformate is not to be classified as chronically hazardous to the aquatic environment.