Registration Dossier

Toxicological information

Repeated dose toxicity: inhalation

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Administrative data

Endpoint:
short-term repeated dose toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
28/07/2016 - 25/08/2016
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2016
Report Date:
2016

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 412 (Subacute Inhalation Toxicity: 28-Day Study)
Version / remarks:
(2009)
Deviations:
no
GLP compliance:
yes
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Hexyl salicylate
- Analytical purity: One sample was 50% solution in DEP and the other was 100% pure
Specific details on test material used for the study:
SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 50064843
- Expiration date of the lot/batch: 14 April 2018
STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: 15 – 25 °C
- Solubility in water : 2 mg/l at 23 °C

Test animals

Species:
rat
Strain:
Wistar
Details on species / strain selection:
Young adult, male and female Wistar outbred rats (Crl:WI(Han)) were obtained from a colony maintained under specific pathogen-free (SPF) conditions at Charles River, Germany.
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River, Germany
- Females nulliparous and non-pregnant: yes
- Age at study initiation: 7-9 weeks
- Weight at study initiation: mean males= 251g, mean females =171g
- Fasting period before study: overnight fasting
- Housing:Macrolon cages with wood shavings
- Diet:ad libitum except during exposure and – for animals of the main study – the overnight fasting period before sacrifice.
- Water: ad libitum except during exposure
ENVIRONMENTAL CONDITIONS
- Temperature (°C):22 ± 2°C
- Humidity (%): 45-65%
- Air changes (per hr): 10
- Photoperiod (hrs dark / hrs light):12/12

IN-LIFE DATES: From:28/07/2016 To:25/08/2016

Administration / exposure

Route of administration:
inhalation
Type of inhalation exposure:
nose only
Vehicle:
air
Mass median aerodynamic diameter (MMAD):
>= 2.6 - <= 3.3 µm
Remarks on MMAD:
The average particle size (MMAD) of the aerosol was 3.3 μm (gsd of 1.7), 2.9 μm (gsd of 1.8) and 2.6 μm (gsd of 1.9) for the low, mid and high concentration test atmospheres, respectively.
Details on inhalation exposure:
GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: The inhalation equipment was designed to expose the animals to a continuous supply of fresh test atmosphere. The test atmospheres were generated by nebulization using an air-driven atomizer which was placed at the top inlet of the exposure chamber. For generation of the low concentration test atmosphere, the atomizer was heated to reduce the aerodynamic particle size.

The amount of test material delivered to the atomizer was controlled using a motor-driven syringe pump.The atomizer was supplied with dry compressed air, controlled at a pressure of 4 bar using a reducing valve. Air flow to the atomizer was measured using a mass view meter. In the top of the exposure unit, a bypass stream of humidified compressed air was added, the flow of which was controlled and measured using rotameters which were calibrated at the settings used during the study using a volumetric flow meter. the air supply to the various rotameters was controlled by mass flow controller.From the top of the exposure chamber, the test atmosphere was directed downward and led to the noses of the animals. At the bottom of the unit the test atmosphere was exhausted.

The exposure unit for the control animals was supplied with a flow of humidified compressed air only, which was controlled using a reducing valve and measured by mass view meter
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
The overall average actual concentrations of Hexyl salicylate in the test atmospheres were determined by gravimetric analysis
Duration of treatment / exposure:
Exposure was over a 28-day period, with a total number of 20 exposure days.
Frequency of treatment:
6 hours/day for 5 days/week
Doses / concentrationsopen allclose all
Dose / conc.:
0 mg/m³ air
Remarks:
Actual concentration in air
Dose / conc.:
10.9 mg/m³ air
Remarks:
Actual concentration in air
Dose / conc.:
52.3 mg/m³ air
Remarks:
Actual concentration in air
Dose / conc.:
249 mg/m³ air
Remarks:
Actual concentration in air
No. of animals per sex per dose:
5/sex/dose
Control animals:
yes
Details on study design:
Animal selection was random
- Dose selection rationale: concentrations were based on the results of a preceding 7-day range finding study (5 exposure days in total). Results for this study are presented in Annex 10 of the study report.
- Post exposure period: Amimals were subject to necropsy on the day following the last exposure.

Positive control:
Not required for this study type

Examinations

Observations and examinations performed and frequency:
CAGE SIDE OBSERVATIONS and DETAILED CLINICAL OBSERVATIONS: Yes
On days of exposure, each animal was observed daily in the morning, prior to exposure, by cage-side observations and, if necessary, handled to detect signs of toxicity. All animals were thoroughly checked again after exposure. Clinical signs listed but not limited to Annex 6 of the study report were used for the recording of clinical observations. During exposure, a group-wise observation was made about halfway through the 6-hour exposure period.

BODY WEIGHT: Yes
Body weight of each animal was recorded 2 days before the start of exposure. These pre-test weights served as a basis for animal allocation. Subsequently, the animals of the main study were weighed prior to exposure on the first day (day 0), and then every 3 or 4 days, including the day of scheduled sacrifice. The animals were also weighed on the day before overnight fasting (prior to the scheduled sacrifice).

FOOD CONSUMPTION: Yes
Food consumption was measured per cage by weighing the feeders. Food consumption was measured over three 7-day periods, starting on day 0, followed by a 6-day period. The results were expressed in g per animal per day.

HAEMATOLOGY: Yes
Hematology was conducted in samples collected from all animals at necropsy. Blood samples were taken from the abdominal aorta of the rats.
- Anaesthetic used for blood collection: Yes (pentobarbital anaesthesia) EDTA or citrate (for prothrombin time) were used as anticoagulant.
- Animals fasted: Yes (Overnight before necropsy but water was freely available)

CLINICAL CHEMISTRY: Yes
Hematology was conducted in samples collected from all animals at necropsy.
- Animals fasted: Yes (Overnight before necropsy but water was freely available)

Sacrifice and pathology:
GROSS PATHOLOGY: Yes. All animals were subject to gross necropsy
HISTOPATHOLOGY: Yes. A detailed assessment was made of all animals
Other examinations:
ORGANS EXAMINED AT NECROPSY: Yes
- Organ weights: adrenals , lungs with trachea and larynx, brain, spleen, heart, testes, kidneys, thymus, liver
Statistics:
-Body weight data collected after initiation of treatment: ‘AnCova & Dunnett’s Test’ with automatic data transformation. Day 0 body weight data were used as covariate in the analysis of the post-treatment data unless removed during data pre-processing.
-Pre-treatment body weight, organ weight, hematology and clinical chemistry data: ‘Generalized Anova/Ancova Test’ with automatic data transformation method
-Incidences of histopathological changes: Fisher’s exact probability test
-Food consumption: no statistics was applied on food intake (only one cage per sex)
Tests were performed as two-sided tests with results taken as significant where the probability of the results is <0.05 or <0.01.

Results and discussion

Results of examinations

Clinical signs:
effects observed, non-treatment-related
Description (incidence and severity):
No treatment-related clinical abnormalities were observed. The few signs noted were considered unrelated to the exposure to the test material. Abnormalities of the skin or fur (sparsely haired areas, encrustations, skin wounds) were observed across the groups. These are common findings, possibly caused by slight movement of the animals in the restraining tubes during exposure (resulting in slight irritation of the skin) or by placing of the subcutaneous transponder. Other clinical signs, observed incidentally in single animals, also represented background findings and were not related to exposure to the test material.
Mortality:
no mortality observed
Description (incidence):
All animals survived until scheduled sacrifice.
Body weight and weight changes:
effects observed, treatment-related
Description (incidence and severity):
Male animals of the high concentration group showed a statistically significantly lower bodyweight than controls from Day 21 until the end of the study. Overall body weight gain during the 28-day period was statistically significantly decreased in males of the high concentration group when compared to unexposed controls. There were no statistically significant differences in body weights of the female rats between the test groups and controls. At Day 14, a temporary and slight decrease in body weight was noted in all female rats, which was not considered to be treatment related. The reason for this slight decrease in all female rats remained uncertain.
Food consumption and compound intake (if feeding study):
effects observed, non-treatment-related
Description (incidence and severity):
Food consumption was slightly decreased in all males at the higher concentrations.
Food efficiency:
not examined
Water consumption and compound intake (if drinking water study):
not examined
Ophthalmological findings:
not examined
Haematological findings:
effects observed, non-treatment-related
Description (incidence and severity):
There were no statistically significant changes in red blood cell variables, coagulation parameters and white blood cell variables in male rats. In females there were no statistically significant changes in red blood cell variables, except for an incidental decrease in reticulocytes in the low concentration group which was considered to be a chance finding because no changes were observed in the mid and high concentration group. Prothrombin time was slightly, but statistically significantly, increased in the high concentration group. The absolute and relative numbers of neutrophils were statistically significantly decreased and the percentage of lymphocytes was statistically significantly increased in females in the low concentration group. The percentage of monocytes was statistically significantly increased in females in the mid concentration group. These findings were considered chance findings because they were not confirmed at the high concentration level.
Clinical biochemistry findings:
effects observed, non-treatment-related
Description (incidence and severity):
In males there were no statistically significant differences in clinical chemistry variables except for a slight increase in mean albumin/globulin ratio in the high concentration group. In the absence of any changes in albumin and total protein levels, or any corroborative findings in females, a minor change in this calculated parameter was considered a chance finding. In females of the high concentration group a statistically significant increase in plasma ALP activity was observed.
Urinalysis findings:
not examined
Behaviour (functional findings):
not examined
Immunological findings:
not examined
Organ weight findings including organ / body weight ratios:
no effects observed
Description (incidence and severity):
There were no statistically significant differences in absolute and relative organ weights between the control group and the groups exposed to the test material
Gross pathological findings:
effects observed, non-treatment-related
Description (incidence and severity):
The few gross changes observed represented background pathology in rats of this strain and age and occurred only incidentally or at random incidence in the different groups
Neuropathological findings:
not examined
Histopathological findings: non-neoplastic:
effects observed, non-treatment-related
Description (incidence and severity):
The histopathological changes observed such as thymus microhaemorrage were about equally distributed amongst the different treatment groups or occurred in one or a few animals only. They are common findings in rats of this strain and age or occurred as individual chance findings. See Table 12 and appendix 8 of the study report. These changes were therefore considered to be unrelated to the exposure to the test material.
Histopathological findings: neoplastic:
no effects observed
Other effects:
no effects observed

Effect levels

Key result
Dose descriptor:
NOAEC
Effect level:
249 mg/m³ air
Based on:
test mat.
Sex:
male/female
Remarks on result:
not determinable due to absence of adverse toxic effects
Remarks:
Inhalation exposure to hexyl salicylate up to a concentration of 249 mg/m3 was tolerated well by the animals and did not result in any adverse exposure-related changes

Target system / organ toxicity

Key result
Critical effects observed:
no

Any other information on results incl. tables

Mean body weight

Day 0

Male

Females

0 mg/m3

10 mg/m3

50 mg/m3

250 mg/m3

0 mg/m3

10 mg/m3

50 mg/m3

250 mg/m3

Mean bodyweight day( g)

249.12

250.36

252.14

250.66

168.30

175.76

165.82

172.46

SD

4.89

6.81

8.54

7.21

10.38

5.58

6.94

7.23

N

5

5

5

5

5

5

5

5

Day 4

Male

Females

0 mg/m3

10 mg/m3

50 mg/m3

250 mg/m3

0 mg/m3

10 mg/m3

50 mg/m3

250 mg/m3

Mean bodyweight day( g)

255.58

256.12

259.28

255.00

179.00

186.54

177.96

183.78

SD

6.44

4.83

12.36

6.04

9.62

4.91

7.54

7.68

N

5

5

5

5

5

5

5

5

Day 7

Male

Females

0 mg/m3

10 mg/m3

50 mg/m3

250 mg/m3

0 mg/m3

10 mg/m3

50 mg/m3

250 mg/m3

Mean bodyweight day( g)

254.32

254.28

254.10

248.46

185.38

186.64

181.26

184.68

SD

8.12

6.50

11.93

4.12

8.82

6.06

9.40

8.00

N

5

5

5

5

5

5

5

5

Day 11

Male

Females

0 mg/m3

10 mg/m3

50 mg/m3

250 mg/m3

0 mg/m3

10 mg/m3

50 mg/m3

250 mg/m3

Mean bodyweight day( g)

262.90

263.34

269.56

258.70

191.44

195.14

188.84

191.30

SD

8.60

5.60

14.84

2.94

9.01

6.18

10.46

8.21

N

5

5

5

5

5

5

5

5

Day 14

Male

Females

0 mg/m3

10 mg/m3

50 mg/m3

250 mg/m3

0 mg/m3

10 mg/m3

50 mg/m3

250 mg/m3

Mean bodyweight day( g)

265.64

263.24

269.00

256.68

178.26

182.82

183.54

186.50

SD

9.30

8.00

13.79

2.96

10.57

4.86

11.88

10.14

N

5

5

5

5

5

5

5

5

Day 18

Male

Females

0 mg/m3

10 mg/m3

50 mg/m3

250 mg/m3

0 mg/m3

10 mg/m3

50 mg/m3

250 mg/m3

Mean bodyweight day( g)

273.10

271.54

278.88

266.26

198.60

199.58

195.98

201.54

SD

9.09

9.39

14.02

2.75

13.61

7.26

11.44

13.12

N

5

5

5

5

5

5

5

5

Day 21

Male

Females

0 mg/m3

10 mg/m3

50 mg/m3

250 mg/m3

0 mg/m3

10 mg/m3

50 mg/m3

250 mg/m3

Mean bodyweight day( g)

275.66

270.64

277.04

261.98*

199.18

204.12

194.06

202.22

SD

9.72

9.74

14.67

4.19

11.32

6.49

10.66

10.41

N

5

5

5

5

5

5

5

5

Day 25

Male

Females

0 mg/m3

10 mg/m3

50 mg/m3

250 mg/m3

0 mg/m3

10 mg/m3

50 mg/m3

250 mg/m3

Mean bodyweight day( g)

285.68

279.96

291.18

274.68*

202.80

208.80

197.64

210.34

SD

10.48

10.17

14.52

2.35

11.90

7.52

9.30

10.42

N

5

5

5

5

5

5

5

5

Day 27

Male

Females

0 mg/m3

10 mg/m3

50 mg/m3

250 mg/m3

0 mg/m3

10 mg/m3

50 mg/m3

250 mg/m3

Mean bodyweight day( g)

287.38

279.10

286.46

272.72*

209.28

208.52

202.60

208.22

SD

11.92

8.89

13.74

1.40

15.04

7.36

15.54

11.32

N

5

5

5

5

5

5

5

5

 * = p < 0.05

Total and differential white blood cell counts - Male (m) | Female (f)

0

mg/m3

WBC (10E9/L)

Lympho

Absolute (10E9/L)

Neutro Absolute (10E9/L)

Eosino Absolute (10E9/L)

Baso Absolute (10E9/L)

Mono Absolute (10E9/L)

Lymphocytes (%)

Neutrophils (%)

Eosinophils (%)

Basophils (%)

Monocytes (%)

Statistics

(g)

(g)

(g)

(g)

(g1)

(g)

(g)

(g)

(g)

(g)

(g1)

(g)

(g)

(g)

(g)

(g)

(g)

(g2)

(g1)

(g)

(g2)

(g)

Sex

(m)

(f)

(m)

(f)

(m)

(f)

(m)

(f)

(m)

(f)

(m)

(f)

(m)

(f)

(m)

(f)

(m)

(f)

(m)

(f)

(m)

 

Mean

5.16

3.60

4.04 

2.91

0.94

0.57

0.071

0.051

0.005

0.003

0.092

0.056

77.80

80.88

18.70

15.80

1.40

1.36

0.10

0.06

1.84

1.56

SD

1.00

0.80

0.95

0.65

0.10

0.15

0.014

0.027

0.004

0.004

0.010

0.015

3.95

2.72

3.57

 2.45

0.25

0.55

0.07

0.09

0.45

0.36

N

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

10 mg/m3

WBC (10E9/L)

Lympho

Absolute (10E9/L)

Neutro Absolute (10E9/L)

Eosino Absolute (10E9/L)

Baso Absolute (10E9/L)

Mono Absolute (10E9/L)

Lymphocytes (%)

Neutrophils (%)

Eosinophils (%)

Basophils (%)

Monocytes (%)

Mean

4.94

3.58

3.92

3.10

0.86

0.35*

0.065

0.046

0.005

0.005

0.083

0.059

79.22

86.84*

17.42

9.58**

1.30

1.32

0.10

0.12

1.68

1.66

SD

0.66

0.83

0.56

0.71

0.13

0.12

0.018

0.011

0.003

0.003

0.019

0.024

1.93

2.44

2.01

1.62

0.22

0.41

0.07

0.08

0.33

0.66

N

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

50 mg/m3

WBC (10E9/L)

Lympho

Absolute (10E9/L)

Neutro Absolute (10E9/L)

Eosino Absolute (10E9/L)

Baso Absolute (10E9/L)

Mono Absolute (10E9/L)

Lymphocytes (%)

Neutrophils (%)

Eosinophils (%)

Basophils (%)

Monocytes (%)

Mean

6.06

3.08

4.85

2.46

0.99

0.48

0.075

0.047

0.006

0.002

0.126

0.077

80.00

79.82

16.36

15.58

1.28

1.52

0.10

0.08

1.96

2.48*

SD

1.38

0.31

 1.09

0.23

0.31

0.08

0.032

0.017

0.001

0.002

0.078

0.018

4.31

1.76

3.50

1.77

0.52

0.41

0.00

0.08

0.87

0.48

N

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

250 mg/m3

WBC (10E9/L)

Lympho

Absolute (10E9/L)

Neutro Absolute (10E9/L)

Eosino Absolute (10E9/L)

Baso Absolute (10E9/L)

Mono Absolute (10E9/L)

Lymphocytes (%)

Neutrophils (%)

Eosinophils (%)

Basophils (%)

Monocytes (%)

Mean

4.76

4.38

 3.60

3.57

0.99

0.65

0.066

0.065

0.005

0.003

0.088

0.075

75.48

81.30

20.90

15.06

1.42

1.50

0.10

0.08

1.84

1.70

SD

0.34

0.61

0.36

0.63

0.14

0.13

0.027

0.020

0.003

0.002

0.034

0.024

3.67

4.07

3.19

3.73

0.65

0.44

0.07

0.04

0.69

0.41

N

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

[g] - Anova & Dunnett* = p < 0.05; ** = p < 0.01

[g1] - Kruskal-Wallis & Dunnett on Ranks

[g2] - Anova & Dunnett(Log)

 

Red blood cell and coagulation parameter – Male (m) | Female (f)                                                                                    

0

mg/m3

RBC

(10E12/L)

Hb

(mmol/L)

PCV

(L/L)

MCV

(fL)

MCH

(fmol)

MCHC

(mmol/L)

Reticulo

cytes

(%)

Thrombo

cytes

(10E9/L)

Prothrom

Time

(s)

Statistics

(g)

(g)

(g)

(g)

(g)

(g)

(g)

(g)

(g)

(g)

(g)

(g)

(g1)

(g)

(g)

(g1)

(g)

(g)

Sex

(m)

(f)

(m)

(f)

(m)

(f)

(m)

(f)

(m)

(f)

(m)

(f)

(m)

(f)

(m)

(f)

(m)

(f)

Mean

8.584

8.170

9.72

9.46

0.4552

0.4356

53.04

53.33

1.133

1.158

21.36

21.72

2.158

2.056

769.2

823.2

21.94

22.26

SD

0.172

0.151

0.16

0.17

0.0116

0.0036

1.34

0.98

0.018

0.035

0.50

0.27

0.320

0.382

34.9

120.1

1.93

0.88

N

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

 

5

5

10 mg/m3

RBC

10E12/L

Hb

(mmol/L)

PCV

(L/L)

MCV

(fL)

MCH

(fmol)

MCHC

(mmol/L)

Reticulo

cytes

(%)

Thrombo

cytes

(10E9/L)

Prothrom

Time

(s)

Mean

8.662

8.296

9.70

9.64

0.4600

0.4426

53.11

53.35

1.121

1.162

21.09

21.78

1.932

1.288**

776.2

863.2

22.70

22.42

SD

0.230

0.232

0.14

0.23

0.0102

0.0125

0.71

0.67

0.037

0.021

0.54

0.29

0.149

0.101

35.1

24.0

1.69

0.54

N

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

50 mg/m3

RBC

(10E12/L)

Hb

(mmol/L)

PCV

(L/L)

MCV

(fL)

MCH

(fmol)

MCHC

(mmol/L)

Reticulo

cytes

(%)

Thrombo

cytes

(10E9/L)

Prothrom

Time

(s)

Mean

8.308

7.856

9.52

9.28

0.4496

0.4188

54.16

53.33

1.148

 1.182

21.20

22.16

2.012

1.690

789.8

802.2

22.08

22.28

SD

0.484

0.261

0.26

0.16

0.0240

0.0087

1.85

0.77

0.046

0.024

0.55

0.21

0.478

0.223

31.6

55.2

1.43

0.95

N

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

250 mg/m3

RBC

(10E12/L)

Hb

(mmol/L)

PCV

(L/L)

MCV

(fL)

MCH

(fmol)

MCHC

(mmol/L)

Reticulo

cytes

(%)

Thrombo

cytes

(10E9/L)

Prothrom

Time

(s)

Mean

8.672

8.000

9.76

9.34

0.4598

0.4264

53.04

53.32 

1.126

1.168

21.23

21.91

1.936

1.696

765.8

747.4

24.14

23.70*

SD

0.213

0.322

0.21

0.15

0.0086

0.0132

1.18

1.07

0.018

0.031

0.30

0.46

0.390

0.227

30.7

75.0

2.33

0.33

N

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

[g] - Anova & Dunnett: * = p < 0.05; ** = p < 0.01

[g1] - Kruskal-Wallis & Dunnett on Ranks

 

 

Clinical chemistry– Male (m) | Female (f)

0

mg/m3

ALP (U/L)

ASAT (U/L)

ALAT (U/L)

GGT (U/L)

Bilirub Total (umol/L)

Creatinine (umol/L)

Total Protein (g/L)

Albumin (g/L)

Albumin / Globulin

Glucose Plasma (mmmol/L)

Statistics

(g)

(g)

(g1)

(g)

(g)

(g)

(g1)

(g)

(g1)

(g)

(g)

(g)

(g1)

(g)

(g1)

(g)

(g)

(g2)

(g)

(g)

Sex

(m)

(f)

(m)

(f)

(m)

(f)

(m)

(f)

(m)

(f)

(m)

(f)

(m)

(f)

(m)

(f)

(m)

(f)

(m)

(f)

Mean

160.2

74.8

90.6

77.4

53.8

37.0

0.08

0.08

1.38

1.14

32.6

30.4

55.2

57.2

29.6

31.4

1.158

1.218

7.102

5.966

SD

37.4

19.8

3.6

11.8

8.5

7.1

0.18

0.18

0.18

0.34

2.6

4.2

0.8

1.5

0.5

0.9

0.051

0.039

0.642

0.810

N

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

10 mg/m3

ALP (U/L)

ASAT (U/L)

ALAT (U/L)

GGT (U/L)

Bilirub Total (umol/L)

Creatinine (umol/L)

Total Protein (g/L)

Albumin (g/L)

Albumin / Globulin

Glucose Plasma (mmmol/L)

Mean

149.2

76.4

80.8

70.0

54.6

36.0

0.12

0.10

1.44

1.28

31.8

31.0

55.4

57.2

29.8

32.2

1.166

1.290

6.992

5.750

SD

41.6 

15.7

5.5

7.0

5.6

7.3

0.27

0.17

0.36

0.62

5.4

3.2

1.9

2.6

0.8

1.1

0.051

0.048

1.253

0.854

N

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

50 mg/m3

ALP (U/L)

ASAT (U/L)

ALAT (U/L)

GGT (U/L)

Bilirub Total (umol/L)

Creatinine (umol/L)

Total Protein (g/L)

Albumin (g/L)

Albumin / Globulin

Glucose Plasma (mmmol/L)

Mean

129.8

94.0

83.8

74.8

46.8

35.6

0.02

0.24

1.12

1.62

30.8

31.0

55.4

56.0

29.6

31.0

1.150

1.244

7.004

5.180

SD

18.6

27.0

8.8

9.3

6.6

5.5

0.04

0.36

0.65

0.38

4.9

3.2

1.5

2.4

0.5

1.4

0.060

0.087

0.645

0.614

N

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

250 mg/m3

ALP (U/L)

ASAT (U/L)

ALAT (U/L)

GGT (U/L)

Bilirub Total (umol/L)

Creatinine (umol/L)

Total Protein (g/L)

Albumin (g/L)

Albumin / Globulin

Glucose Plasma (mmmol/L)

Mean

148.8

124.2*

 97.8

85.4

53.6

46.4

0.00

0.00

1.18

1.64

32.8

31.6

53.4

54.2

29.6

30.2

1.245*

1.261

7.010

4.872

SD

52.3

33.8

12.5

8.6

12.7

7.6

0.00

0.00

0.30

0.36

3.8

1.7

1.1

2.9

0.5

1.3

0.042

0.058

0.747

0.491

N

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

[g] - Anova & Dunnett: * = p < 0.05

[g1] - Kruskal-Wallis & Dunnett on Ranks

 

 

 

 

Applicant's summary and conclusion

Conclusions:
Under the conditions of the current study, inhalation exposure to hexyl salicylate up to a concentration of 249 mg/m3 was tolerated well by the animals and did not result in any adverse exposure-related changes.
Executive summary:

The toxicity of hexyl salicylate following repeated inhalation exposure was investigated in a sub-acute (28-day) toxicity study in rats. Four groups of 5 male and 5 female rats each were exposed nose-only to concentrations of 0 (controls), 10.9, 52.3 or 249 mg/m3 hexyl salicylate for 6 hours/day, 5 days/week over a 28 -day period, with a total number of 20 exposure days. The average particle size (MMAD) of the aerosol was 3.3 μm (gsd of 1.7), 2.9 μm (gsd of 1.8) and 2.6 μm (gsd of 1.9) for the low, mid and high concentration test atmospheres, respectively. Animals were sacrificed on the day after the last exposure. The target concentration levels for this sub-acute study were selected on the basis of the results of a preceding 7 -day range finding study. Exposure was well tolerated. Exposure to 250 mg/m3 resulted in slightly decreased growth and food consumption in male rats. No exposure-related changes were observed at 10 and 50 mg/m3. No treatment-related clinical abnormalities were observed. During the last week of the exposure the average body weight of male animals of the high concentration group was slightly, but statistically significantly below controls. Since the relative difference with controls was small (about 5% at most), this finding – although likely to be treatment-related - was considered to be of little, if any, toxicological significance. The few slight, but statistically significant differences in clinical pathology parameters in females of the high concentration group (increased plasma ALP activity and prothrombin time) were considered chance findings – and therefore not treatment related – because they were observed in one sex only, the difference with controls was small, and no changes were observed in any of the associated parameters investigated. No changes were observed in absolute and relative organ weights. No macroscopic pathological changes were observed at necropsy, and treatment related histopathological abnormalities were not observed. A NOAEC of 249 mg/m3 is therefore derived for this study, in the absence of any adverse treatment-related findings at the highest exposure level.