Ametryn

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

0 mg/L

Assessment factor:

10

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

0 mg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

0 mg/L

Assessment factor:

100

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:

0.003 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

0 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:

PNEC oral

PNEC value:

0.147 mg/kg food

Assessment factor:

30

Additional information

PNEC water(freshwater)

 

		Value		Assessment factor		Remarks/Justification
PNEC water (freshwater)		0.00011 mg/L		10		Based on the results of long-term toxicity studies with aquatic organisms

 

The general principle of the method given by the ECHA guidance on information requirements and chemical safety assessment, Chapter R.10 (May 2008)is that the result from a laboratory test is divided by an appropriate assessment factor. PNECs are estimated by division of the lowest value for the toxicity with the relevant assessment factor. Results of long-term tests are preferred to those of short-term tests, because such results give a more realistic picture of effects on the organisms during their entire life cycle.

 

Long-term results from fish, daphnia and algae representing three trophic levels are available. The most critical long-term result is the 72 hours NOEC on Algae, 0.0011 mg/L. Therefore, it seems appropriate in this assessment to consider 0.0011 mg/L as the lowest end of the long-term toxicity range for aquatic organisms. This range covers three taxonomic groups, fish, invertebrates and algae, and taking into account the recommendations of the ECHA guidance, a factor of 10 to the lowest end of the long-term toxicity range is applied, obtaining a PNEC for aquatic organisms of 0.00011 mg/L.

 

PNEC aquatic organisms = long-term toxicity range/10 = 0.00011 mg/L

 

 

PNEC water (marine water)

 

	Value	Assessment factor	Remarks/Justification
PNEC water (marine water)	0.000011 mg/L	100	Based on the results of long-term toxicity studies with aquatic organisms

 

The general principle of the method given by the ECHA guidance on information requirements and chemical safety assessment, Chapter R.10 (May 2008) is that the result from a laboratory test is divided by an appropriate assessment factor. PNECs are estimated by division of the lowest value for the toxicity with the relevant assessment factor. Results of long-term tests are preferred to those of short-term tests, because such results give a more realistic picture of effects on the organisms during their entire life cycle.

 

The data set does not include test data on marine water species but long-term results on freshwater species representing three trophic levels (fish, daphnia and algae). Therefore, in absence of data on saltwater species the PNEC for aquatic organisms can be used for both, freshwater and marine environments and divided by the appropriate assessment factor. The most critical long-term result is the 72 hours NOEC on Algae, 0.0011 mg/L. Therefore, it is appropriate to consider 0.0011 mg/L as the lowest end of the long-term toxicity range for aquatic organisms. This range covers three taxonomic groups, fish, invertebrates and algae, and taking into account the recommendations of the ECHA guidance, a factor of 100 to the lowest end of the long-term toxicity range is used, obtaining a PNEC for aquatic organisms of 0.000011 mg/L.

 

PNEC aquatic organisms = long-term toxicity range/100 = 0.000011 mg/L

 

 

PNEC water (intermittent release)

 

	Value	Assessment factor	Remarks/Justification
PNEC water (intermittent release)	0.000032 mg/L	100	Based on the results of short-term toxicity studies with aquatic organisms

 

The general principle given by the ECHA guidance on information requirements and chemical safety assessment, Chapter R.10 (May 2008) is that the PNEC-values derived for freshwater or marine waters are based on the implicit assumption that the environmental exposure is constant. However, in many cases, discharges will be limited in time. In such cases, the environmental exposure will also be limited in time, and it is assumed that when exposure stops rapidly, populations can tolerate higher concentrations than when it is long lasting.

 

The most critical short-term toxicity result is the 72 hours EC50 on Algae, 0.0032 mg/L. Therefore, it seems appropriate in this assessment to consider 0.0032 mg/L as the lowest end of the short-term toxicity range for aquatic organisms. This range covers three taxonomic groups, fish, invertebrates and algae, and taking into account the recommendations of the ECHA guidance, a factor of 100 to the lowest end of the short-term toxicity range is applied, obtaining a PNEC for aquatic organisms of 0.000032 mg/L.

 

PNEC aquatic organisms = short-term toxicity range/100 = 0.000032 mg/L

 

 

PNEC Sewage Treatment Plant (STP)

 

	Value	Assessment factor	Remarks/Justification
PNEC Sewage Treatment Plant (STP)	10 mg/L	100	Based on the results of a sludge respiration test

 

The general principle of the method given by the ECHA guidance on information requirements and chemical safety assessment, Chapter R.10 (May 2008) is that the result from a laboratory test is divided by an appropriate assessment factor. PNECs are estimated by division of the lowest value for the toxicity with the relevant assessment factor.

 

An assessment factor (AF) of 10 is to be applied to the NOEC of a sludge respiration test, reflecting the lower sensitivity of this endpoint as compared to nitrification, as well as the short duration of the test. The corresponding AF is 100 when based on the EC50.

 

The lowest short-term toxicity result is the three-hour EC50 result of the on Activated Sludge Respiration Inhibition Test, >1000 mg/L. Therefore, it is appropriate in this assessment to consider 1000 mg/L as the lowest end of the short-term toxicity range for microorganisms. According to ECHA guidelines, an assessment factor of 100 to the lowest end of the short-term toxicity range is used, obtaining a PNEC for aquatic organisms of 10 mg/L.

 

PNEC microorganisms = short-term toxicity range/100 = 10 mg/L

 

 

PNEC sediment (freshwater)

 

	Value	Assessment factor	Remarks/Justification
PNEC sediment (freshwater)	0.0032 mg/kg	Not applicable	Equilibrium partitioning

 

An estimation of the PNEC sediment can be performed according to the equilibrium partitioning method given by the ECHA guidance on information requirements and chemical safety assessment, Chapter R.10 (May 2008):

 

PNEC sediment = (Ksusp-water / RHOsusp) * PNECwater * 1000

 

Where:

Ksusp-water = 7.18 m3 /m3 (according to EUSES2.1)

RHOsusp = 1150 kg/m3 (according to the “R16” Guidance document (2008) equation R16-23)

PNECwater [freshwater] = 0.00011 mg/L

Conversion factor wet-dry suspended matter = 4.6 (according to EUSES2.1)

 

Hence:

PNECsediment wet = (7.18 / 1150) * PNECwater * 1000 = 0.00069 mg/kg

PNECsediment dry = 0.00069 * 4.6 = 0.0032 mg/kg

 

PNEC sediment (marine water)

 

	Value	Assessment factor	Remarks/Justification
PNEC sediment (marine water)	0.00032 mg/kg	Not applicable	Equilibrium partitioning

 

An estimation of the PNEC sediment can be performed according to the equilibrium partitioning method given by the ECHA guidance on information requirements and chemical safety assessment, Chapter R.10 (May 2008):

 

PNEC sediment = (Ksusp-water / RHOsusp) * PNECwater * 1000

 

Where:

Ksusp-water = 7.18 m3 /m3 (according to EUSES2.1)

RHOsusp = 1150 kg/m3 (according to the “R16” Guidance document (2008) equation R16-23)

PNECwater [marine] = 0.000011 mg/L

Conversion factor wet-dry suspended matter = 4.6 (according to EUSES2.1)

 

 

Hence:

PNECsediment = (7.18 / 1150) * PNECwater * 1000 = 0.000069 mg/kg

PNECsediment dry = 0.000069 * 4.6 = 0.00032 mg/kg

 

 

PNEC soil

 

	Value	Assessment factor	Remarks/Justification
PNEC soil	0.00057 mg/kg	Not applicable	Equilibrium partitioning

 

An estimation of the PNECsoil can be estimated via the equilibrium partitioning method given by the ECHA guidance on information requirements and chemical safety assessment, Chapter R.10 (May 2008):

 

PNECsoil = (Ksoil-water / RHOsoil) * PNECwater * 1000

Where:

Ksoil-water = 7.73 m3 /m3 (according to EUSES2.1)

RHOsoil = 1700 kg/m3 (according to the “R16” Guidance document (2008) equation R16-23)

PNECwater [freshwater] = 0.00011 mg/L

Conversion factor wet-dry soil = 1.13 (according to EUSES2.1)

 

Hence:

PNECsoil wet = (7.73 / 1700) * PNECwater * 1000 = 0.00050 mg/kg

PNECsoil dry = 0.00050 * 1.13 = 0.00057 mg/kg

 

PNEC oral

 

	Value	Assessment factor	Remarks/Justification
PNEC oral	0.147 mg/L	30	Based on the results of long-term toxicity studies with mammals

 

The general principle of the method given by the ECHA guidance on information requirements and chemical safety assessment, Chapter R.10 (May 2008) is that the result from a laboratory test is divided by an appropriate assessment factor. PNECs are estimated by division of the lowest value for the toxicity with the relevant assessment factor. Results of long-term tests are preferred to those of short-term tests, because such results give a more realistic picture of effects on the organisms during their entire life cycle.

 

Some long-term repeated dose toxicity studies on mammalians and birds are available. Therefore, it seems appropriate in this assessment to considerthe 2-year dietary NO(A)EL of 4.4 mg/kg bw/d as the lowest end of the long-term toxicity range for mammalians and the 21-days dietary NOEC 300mg/kg for birds. Taking into account the recommendations of the ECHA guidance, an assessment factor of 30 to both the lowest end of the long-term toxicity range is applied, obtaining a PNEC for mammalians of 0.147 mg/L and a PNEC for birds of 10 mg/L.

 

PNEC mammals = long-term toxicity range/30 = 0.147 mg/L

PNEC birds = long-term toxicity range/30 = 10 mg/L

 

Since the PNEC mammals is the lowest value, it will be used for further assessments:

 

PNEC oral = PNEC mammals = 0.147 mg/L

Conclusion on classification

The substance is of concern for the aquatic compartment and it is classified accordingly.