Registration Dossier

Administrative data

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:
PNEC aqua (freshwater)
PNEC value:
0 mg/L
Assessment factor:
1 000
Extrapolation method:
assessment factor
PNEC freshwater (intermittent releases):
0.005 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:
1.17 mg/L
Assessment factor:
100
Extrapolation method:
assessment factor

Sediment (freshwater)

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

Sediment (marine water)

Hazard assessment conclusion:
PNEC sediment (marine water)
PNEC value:
0.295 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:
0.239 mg/kg soil dw
Extrapolation method:
equilibrium partitioning method

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:
no potential for bioaccumulation

Additional information

PNECwater

The lowest endpoint is for algae (EbC500.16 mg.L / ErC500.47 mg/L). Current guidance suggests the EC50for growth rate is used for risk assessment purposes in preference to the EC50for biomass.

No long-term aquatic endpoints are available.

For freshwater, an assessment factor (AF) of 1000 is applied for frequent/constant release:

PNECwater= 0.47 / 1000 = 0.00047 mg/L

For intermittent release, an assessment factor AF of 100 may be applied.

PNECwater, intermittent= 0.47 / 100 = 0.0047 mg/L

For marine water, an AF of 10000 is to be applied to reflect the greater diversity of taxa (producing a broader distribution of species sensitivity) in seawater.

PNECmarine water= 0.47 / 10000 = 0.000047 mg/L

PNECmicroorganisms

The activated sludge respiration inhibition test was performed according to OECD guideline 209 (Activated Sludge, Respiration Inhibition Test).

The following information is taken into account for effects on aquatic micro-organisms for the derivation of PNEC:

No notable inhibition was observed at the 1.9 or 6.1 mg/L nominal test concentrations (equivalent to 1.4, 4.8 mg/L active ingredient), however 8%, 40% and 61% inhibition was observed at nominal test concentrations of 19.5, 62.5 and 200.0 mg/L (equivalent to 14.7, 46.9 and 150.0 mg/L active ingredient), respectively.

Based on Probit analysis, the EC10, EC20 and EC50 were 18, 34 and 117 mg/L MK92K (equivalent to 13.6, 25.8 and 88.0 mg/L active ingredient), respectively. The EC80 could not be reliably determined but can be said to be greater than the highest test concentration, 200 mg/L MK92K (equivalent to >150 mg/L active ingredient). The NOEC is considered to be 6.1 mg/L MK92K (equivalent to 4.6 mg/L active ingredient).

The guideline validity criteria relating to the reference substance response and the variation between the blank control cultures were met. The results of this study are therefore considered valid. Using an assessment factor of 10 results in a PNEC of 0.61 mg/L

Exposure to terrestrial organisms is not expected on the basis of the use pattern of the substance.

Conclusion on classification

Based on the data available, MK92K is classified under Directive 67/548/EEC as (R50/53) Very Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment and under the CLP Regulation ad Aquatic Acute 1 (Hazard statement: H400: Very toxic to aquatic life.)