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Administrative data

Workers - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
2.3 mg/m³
Most sensitive endpoint:
repeated dose toxicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
other: ECHA REACH Guidance and ECETOC Technical Report No. 110
Overall assessment factor (AF):
15
Modified dose descriptor starting point:
NOAEC
DNEL value:
34.1 mg/m³
Explanation for the modification of the dose descriptor starting point:
There are no relevant experimental data on the repeated exposure by inhalation. A conservative approach is used assuming a 50 % absorption rate via the oral route (end route) as compared to the inhalation route (starting route).
AF for dose response relationship:
1
Justification:
The dose response relationship is considered unremarkable, therefore no additional factor is used.
AF for differences in duration of exposure:
2
Justification:
The default extrapolation factor for exposure duration is used: subchronic (starting point) to chronic (end point).
AF for interspecies differences (allometric scaling):
1
Justification:
Respiratory interspecies differences are fully covered by the factors used for route to route extrapolation.
AF for other interspecies differences:
2.5
Justification:
Default factor according to ECHA guidance document.
AF for intraspecies differences:
3
Justification:
Intraspecies differences of workers are considered to be fully covered by the selected factor according to ECETOC Technical Report No. 110.
AF for the quality of the whole database:
1
Justification:
The quality of the whole data base is considered to be sufficient and uncritical.
AF for remaining uncertainties:
1
Justification:
The approach used for DNEL derivation is conservative. No further assessment factors are required.
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

Workers - Hazard via dermal route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
6.5 mg/kg bw/day
Most sensitive endpoint:
repeated dose toxicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
other: ECHA REACH Guidance and ECETOC Technical Report No. 110
Overall assessment factor (AF):
60
Modified dose descriptor starting point:
NOAEL
DNEL value:
386.8 mg/kg bw/day
Explanation for the modification of the dose descriptor starting point:
There are no relevant experimental data on repeated exposure by dermal absorption. Based on the physiochemical properties it is assumed that the test item's absorption corresponds to 10 % of the oral uptake.
AF for dose response relationship:
1
Justification:
The dose response relationship is considered unremarkable, therefore no additional factor is used.
AF for differences in duration of exposure:
2
Justification:
The default extrapolation factor for exposure duration is used: subchronic (starting point) to chronic (end point).
AF for interspecies differences (allometric scaling):
4
Justification:
The default allometric scaling factor for the differences between rats and humans is used.
AF for other interspecies differences:
2.5
Justification:
Default factor according to ECHA guidance document.
AF for intraspecies differences:
3
Justification:
An intraspecies difference factor of 3 for workers is considered to be sufficient (ECETOC Technical Report No. 110).
AF for the quality of the whole database:
1
Justification:
The quality of the whole data base is considered to be sufficient and uncritical.
AF for remaining uncertainties:
1
Justification:
The approach used for DNEL derivation is conservative. No further aassessment factors are required.
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified

Workers - Hazard for the eyes

Local effects

Hazard assessment conclusion:
no hazard identified

Additional information - workers

General

No respective experimental data for cesium chloride are availabe. Consequently, read-across was applied using study results from cesium hydroxide monohydrate. The DNEL derivation is based on the calculated NOAEL for cesium chloride.

DNEL derivation is performed under consideration of the recommendations of ECHA REACH Guidance (2010) and ECETOC (2010). In view of the data used for evaluation, the "quality of whole database factors" and "dose-response factors" are considered to be a value of 1.  

Long term exposure- systemic effect

Inhalation exposure

A subchronic repeated dose toxicity test with cesium chloride is not available. Consequently, read-across was applied using study results from cesium hydroxide monohydrate (please refer to IUCLID section 13 for read-across justification).

In order to derive the worker DNEL (long-term inhalation exposure), the results of the 90-day repeated dose oral toxicity study with the structural analogue cesium hydroxide monohydrate were used (NOAEL 25 mg/kg bw/day). The DNEL derivation is based on the calculated NOAEL for cesium iodide of 38.68 mg/kg bw/day.  

Correction of the dose descriptor:

Oral NOAEL: 38.68 mg/kg bw/day

sRV(rat): 0.38 m3/ kg bw (8 hours) [standard respiratory volume of the rat]

ABS oral (rat)/ ABS inhalation (human): 0.5 [ratio of oral absorption in the rat to inhalative absorption in the human] sRV (human)/ wRV (human): 6.7 m3/ 10 m3= 0.67 m3 [ratio of human standard respiratory volume to worker respiratory volume]

The oral NOAEL= 38.68 mg/kg bw/ day is converted in an inhalation NOAEC= 34.10 mg/ m3.  

Calculation of the worker DNEL:

Corrected inhalatory NOAEC for worker: 34.10 mg/ m3

Assessment factor for exposure duration (subchronic to chronic): 2

Assessment factor for intraspecies differences (worker): 3 

Assessment factor for other interspecies differences: 2.5

Worker DNEL (inhalation exposure) = 34.10 mg/m3/ (1 x 2 x 1 x 3 x 2.5 x 1 x 1) = 34.10 / 15 = 2.27 mg/ m3  

Dermal exposure

A subchronic repeated dose toxicity test with cesium iodide is not available. Consequently, read-across was applied using study results from cesium hydroxide monohydrate. In order to derive the worker DNEL (long-term dermal exposure), the results of the 90-day repeated dose oral toxicity study with the structural analogoue cesium hydroxide monohydrate were used (NOAEL 25 mg/kg bw/day). The DNEL derivation is based on the calculated NOAEL for cesium iodide of 38.68 mg/kg bw/day.  

Considering the appropriate assessment factors, the worker DNEL (long-term dermal exposure) is calculated as follows:  

Correction of the dose descriptor:

Dose descriptor of relevant study: 386.8 mg/kg bw/day (NOAEL x 10; assuming 10 % dermal absorption)

Assessment factor for exposure duration (subchronic to chronic): 2

Allometric scaling factor (rat to human): 4

Assessment factor for other interspecies differences: 2.5

Assessment factor for intraspecies differences (worker): 3 

Taking the above mentioned assessment factors into account, the following worker DNEL is:

Worker DNEL (dermal exposure) = 386.8 mg/kg bw/day / (1 x 2 x 4 x 2.5 x 3 x 1 x 1) = 386.8 / 60 = 6.45 mg/kg bw/day  

Acute/ short term exposure- systemic effect

Inhalation

There is no indication for acute systemic toxicity of cesium iodide. The substance is not classified for inhalation toxicity. Also no peak exposure is expected and particle size excludes inhalative exposure. Therefore no DNEL is required.

Dermal

Based on the results of an acute dermal toxicity study cesium iodide is not classified and labelled for acute systemic toxicity, according to Directive 67/548/EEC (DSD) and Regulation (EC) No 1272/2008 (CLP). Therefore no DNEL was derived.

Acute and long term exposure- local effect

Respiratory irritation

The particle size of cesium sulphate excludes inhalative exposure. Moreover, there is no indication for any adverse local effects as the substance is neither classified for inhalation toxicity nor for irritation/corrosion according to Directive 67/548/EEC (DSD) and Regulation (EC) No 1272/2008 (CLP). Therefore no DNEL is required.

Skin irritation

The test item is not classified for skin irritation/corrosion according to Directive 67/548/EEC (DSD) and Regulation (EC) No 1272/2008 (CLP). Based on study results from cesium nitrate and evidences from experimental studies on cesium hydroxide and cesium iodide (all studies obtained no potential for skin sensitisation) cesium iodide is not classified for skin sensitisation according to Directive 67/548/EEC (DSD) and Regulation (EC) No 1272/2008 (CLP). Therefore no DNEL was derived.   

Eye irritation

The test item is not classified for eye irritation according to Regulation (EC) No 1272/2008 (CLP) and Directive 67/548/EEC (DSD).

References

- ECHA (2010). Guidance on information requirements and chemical safety assessment. Chapter R.8: Characterisation of dose [concentration]-response for human health. Version 2. ECHA-2010 -G-19–N.

- ECETOC (2010). Technical Report 110.Guidance on assessment factors to derive a DNEL. according to Annex VI of Regulation EC 1272/2008 (CLP).

General Population - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

General Population - Hazard via dermal route

Systemic effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified

General Population - Hazard via oral route

Systemic effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

General Population - Hazard for the eyes

Local effects

Hazard assessment conclusion:
no hazard identified

Additional information - General Population

General population is not intended to be exposed to cesium iodide via inhalation, dermal or oral route. Therefore, no DNEL (long-term, inhalation, dermal, oral exposure) is derived for general population.