Sodium dichromate

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

14/12/1982-25/2/1983

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1983

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

GLP compliance:

no

Remarks:

Pre-dates GLP

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Sodium chromate

EC Number:

231-889-5

EC Name:

Sodium chromate

Cas Number:

7775-11-3

Molecular formula:

CrH2O4.2Na

IUPAC Name:

disodium dioxido(dioxo)chromium

Constituent 2

Reference substance name:

Sodium dichromate

EC Number:

234-190-3

EC Name:

Sodium dichromate

Cas Number:

10588-01-9

Molecular formula:

Cr2Na2O7

IUPAC Name:

sodium dichromate

Constituent 3

Reference substance name:

Potassium dichromate

EC Number:

231-906-6

EC Name:

Potassium dichromate

Cas Number:

7778-50-9

Molecular formula:

Cr2H2O7.2K

IUPAC Name:

potassium dichromate

Details on test material:

Yellow powder (sodium chromate)
Orange/red powder (sodium dichromate)
Orange/red powder (potassium dichromate)

Test animals

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Cheshire Farms, Ltd
- Age at study initiation: 10-12 weeks
- Weight at study initiation: 1.67-2.71 kg
- Fasting period before study: Not stated
- Housing: Individual
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 14 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 10-24
- Humidity (%): 40-82
- Air changes (per hr): Not reported
- Photoperiod (hrs dark / hrs light): Not reported


IN-LIFE DATES: From: 14/12/82 To: 25/2/83

Administration / exposure

Type of coverage:

occlusive

Vehicle:

physiological saline

Details on dermal exposure:

TEST SITE
- Area of exposure: Approximately 26.4 cm2
- % coverage: 10
- Type of wrap if used: occlusive tape


REMOVAL OF TEST SUBSTANCE
- Washing (if done): yes
- Time after start of exposure: 24 hours


TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2 g/kg
- Concentration (if solution): moistened with saline (0.15 ml/g)
- Constant volume or concentration used: yes

VEHICLE
- Amount(s) applied (volume or weight with unit): 2 ml/kg
- Concentration (if solution): -
- Lot/batch no. (if required): -
- Purity: -

Duration of exposure:

24 hours

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

Five

Control animals:

yes, concurrent vehicle

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Daily observation; bodyweights recorded on Days 1, 4, 7, 11 and 14
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight, organ weights (brain, lungs, liver, spleen, kidneys, gonads), necropsy

Statistics:

Homogenity of variance (F Max); Student's t-test; Wilcoxon Rank Sum test.

Results and discussion

Preliminary study:

Not reported

Effect levels

Effect levels 1

Sex:

male

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Remarks on result:

other: Sodium dichromate

Effect levels 2

Sex:

female

Dose descriptor:

LD50

Effect level:

< 2 000 mg/kg bw

Remarks on result:

other: Sodium dichromate

Effect levels 3

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Remarks on result:

other: Sodium dichromate

Effect levels 4

Sex:

male

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Remarks on result:

other: Sodium chromate

Effect levels 5

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Remarks on result:

other: Sodium chromate

Effect levels 6

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Remarks on result:

other: Sodium chromate

Effect levels 7

Sex:

male

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Remarks on result:

other: Potassium dichromate

Effect levels 8

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Remarks on result:

other: Potassium dichromate

Effect levels 9

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Remarks on result:

other: Potassium dichromate

Mortality:

Sodium chromate: no males died; one female died on Day 4
Sodium dichromate: One male died on Day 1; three females died on Days 1-6
Potassium dichromate: No males died; two females died between Days 3-6

Clinical signs:

other: Sodium chromate: Green staining, hypokinesia, sneezing, swellilng of the application site Sodium dichromate: Yellow staining, hypokineisa, swollen or encrusted application site Potassium dichromate: Green/blue/yellow.red staining, hunched posture, ataxia,

Gross pathology:

Gross necropsy did not reveal any effects clearly related to treatment in any group.

Other findings:

Mean absolute and relative liver weights were seen in females administered sodium dichromate. No effects were seen on other organ weights and similar effects were not seen in any of the other treated groups.

Any other information on results incl. tables

The significantly lower liver weights seen in females treated with sodium dichromate are not considered to be of toxicological significance as they are associated with low concurrent control values.

Liver weight	Sodium chromate		Controls		Sodium dichromate		Controls		Potassium dichromate		Controls
	M	F	M	F	M	F	M	F	M	F	M	F
Absolute (g)	103	111	110	110	111	116**	116	91	106	103	116	98
Relative (%)	4.4	4.9	4.3	4.3	4.3	5.4**	4.1	3.5	4.3	4.8	4.3	4.4

Applicant's summary and conclusion

Interpretation of results:

Category 4 based on GHS criteria

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

Acute dermal LD50 values for sodium chromate and potassium dichromate were investigated in this study were found to be >2000 mg/kg bw (combined sexes). In case of sodium dichromate females appeared to be slightly more sensitive than males. The acute dermal LD50 values for sodium dichromate were >2000 mg/kg bw/day and <2000 mg/kg bw/day for males and females, respectively. Since the lowest LD50 in this study is <2000 mg/kg bw/day, sodium dichromate needs to be classified as acutely toxic via the dermal route, category 4, H312: Harmful in contact with skin (Signal word: Warning). This classification is in line with the legal classification of sodium dichromate (index number 024-004-00-7).

Executive summary:

Sodium chromate, sodium dichromate and potassium dichromate (moistened with saline) were administered for 24 hours under occlusive conditions to the shorn dorsal skin of groups of New Zealand White Rabbits (5/sex). Animals were observed for 14 days.

Deaths occurred in the groups treated with sodium chromate (1F), sodium dichromate (1M, 3F) and potassium dichromate (2F). Signs of systemic toxicity and local dermal effects were observed in each treatment group. Body weights were unaffected by treatment. Gross necropsy did not reveal any clearly treatment-related effects. Significantly higher absolute and relative liver weights seen in sodium dichromate-treated animals are associated with low concurrent controls and are considered to be of minimal toxicological significance.

Acute dermal LD50 values for sodium chromate and potassium dichromate were investigated in this study were found to be >2000 mg/kg bw (combined sexes). In case of sodium dichromate females appeared to be slightly more sensitive than males. The acute dermal LD50 values for sodium dichromate were >2000 mg/kg bw/day and <2000 mg/kg bw/day for males and females, respectively.