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Diss Factsheets

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Stability

Phototransformation in air

No experimental data available. As this study is not a standard information requirement in REACH and there is no indication from the CSA on the need to investigate further the fate and behaviour of the substance (Annex X requirement), no further testing is considered necessary.

Hydrolysis

In accordance with Column 2 adaptation statement of REACH Annex VIII, hydrolysis as a function of pH, information requirement 9.2.2.1, does not need to be conducted if the test substance is readily biodegradable. Since the half life for tin (II) oxalate was found to be 37.5 days so the estimation indicates that the substance is readily biodegradable. Hence this study was considered for waiver.

Phototransformation in water

No experimental data available. As this study is not a standard information requirement in REACH and there is no indication from the CSA on the need to investigate further the fate and behaviour of the substance (Annex X requirement), no further testing is considered necessary.

Phototransformation in soil

No experimental data available. As this study is not a standard information requirement in REACH and there is no indication from the CSA on the need to investigate further the fate and behaviour of the substance (Annex X requirement), no further testing is considered necessary.

Biodegradation

Biodegradation in water

No. of studies reviewed for Biodegradation in water:screening tests from reliable sources having Klimisch rating 2.

The summary of the results are presented below

Sr.No

Endpoint

Percentage Degradation

Half - Life

Parameter

Sources

1

Ready biodegradability

50% degradation

37.5 days

Half-life

Predicted data from PBT profiler

2

Ready biodegradability

90.26 % degradation

15 days

O2 consumption

Predicted data from QSAR

 

By applying weight of evidence approach to the target chemical tin(II) oxalate it was found that the degradation percentage of tin(II) oxalate in water medium is 50 to 90.26 %.This result in ready biodegradability of the chemical. 

Biodegradation in water and sediment

Based on the Level III Fugacity Model,the half life period of the tin(II) oxalate was estimated. The half life period of tin (II) oxalate in water is 900hrs (37.5 d) therefore it is considered that the substance will qualify as not persistent as the half life does not exceed the threshold of 60 days. So, it can be confirmed that the substance is readily biodegradable in water medium where as in sediment the half life is 8100 hrs (337.5 d).

Based on this value, it can be inferred that the substance is persistent in sediment medium and is not readily biodegradable probably due to the anaerobic conditions existing in most sediments. However, it can be observed that tin(II) oxalate does not diffuse in the sediment medium since it's percentage diffusion in the sediment medium is reported to be 0.0872 % and hence persistence in the sediment compartment is not likely to be critical.

 

Mass Amount

(percent)

Half-Life

(hr)

Emissions

(kg/hr)

Water

44.4

900

1000

Sediment

0.0872

8.1e+003

0

 

Fugacity

(atm)

Reaction

(kg/hr)

Advection

(percent)

Reaction

(percent)

Advection

(percent)

Water

1.27e-009

578

750

19.3

25

Sediment

1.21e-009

0.126

0.0295

0.00421

0.000984

Biodegradation in soil

The EPI Suite has estimated that tin(II) oxalate is expected to be found predominantly in soil and its persistence estimate is based on its transformation in this medium. Its half-life in soil, 75 days (1800 hrs). This dose not exceeds the threshold of 120 days as per Annex XIII of REACH. Therefore, tin(II) oxalate is estimated to be not persistent in the soil environment.

Fugacity Model by EPI Suite estimation database

 

Mass Amount

(percent)

Half-Life

(hr)

Emissions

(kg/hr)

Soil

47.5

1800

1000

 

 

Fugacity

(atm)

Reaction

(kg/hr)

Advection

(percent)

Reaction

(percent)

Advection

(percent)

Soil

4.64e-008

309

0

10.3

0

Bioaccumulation

No. of studies reviewed for bioaccumulation from reliable sources having Klimisch rating 2.

 

The summary of the results are presented below

 

Sr.No

Endpoint

Effect values

Interpretation of results

Species

Sources

1

BCF

100

Non -bioaccumulative

Fish

 Predicted data from EPI Suite

2

BCF

88.73

Non -bioaccumulative

Oncorhynchus kisutch

Predicted data from QSAR

 

By applying weight of evidence approach to the target substance tin(II) oxalate,the endpoint value of bioaccumulation was found to vary between BCF = 88.73 to 100 in aquatic organisms /fish.Thus it is concluded that the test substancetin(II) oxalateis not expected to bioaccumulate in the food chain because it does not exceed the BCF criteria.

Transport and distribution

Adsorption / desorption

Soil Adsorption Coefficient i.e Koc value of tin(II) oxalate was estimated as 1 L/kg by means of MCI method. This indicates that tin(II) oxalate will have negligible sorption to soil and sediment, rapid migration potential to groundwater.This Koc value when converted at 20 degC is equivalent to 0.8.

Henry's Law constant

Henry's Law states that at a constant temperature, the amount of a given gas that dissolves in a given type and volume of liquid is directly proportional to the partial pressure of that gas in equilibrium with that liquid. Henrys Law Constant of tin(II) oxalate at 25 deg C is 7.07 Pa m³/mol.