Pyrolytic lignin

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

March 2021

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2021

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Low molecular weight organic substances from fast pyrolysis bio-oil

IUPAC Name:

Low molecular weight organic substances from fast pyrolysis bio-oil

Constituent 2

Reference substance name:

Monomers from fast pyrolysis bio-oil

IUPAC Name:

Monomers from fast pyrolysis bio-oil

Constituent 3

Reference substance name:

Dimers from fast pyrolysis bio-oil

IUPAC Name:

Dimers from fast pyrolysis bio-oil

Constituent 4

Reference substance name:

Trimers from fast pyrolysis bio-oil

IUPAC Name:

Trimers from fast pyrolysis bio-oil

Constituent 5

Reference substance name:

Higher oligomers from fast pyrolysis bio-oil

IUPAC Name:

Higher oligomers from fast pyrolysis bio-oil

Constituent 6

Reference substance name:

Water

EC Number:

231-791-2

EC Name:

Water

Cas Number:

7732-18-5

Molecular formula:

H2O

IUPAC Name:

water

Test material form:

liquid: viscous

Remarks:

Brown /black highly vicous liquid

Test animals

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Institute of Experimental Pharmacology and Toxicology, Center of Experimental Medicine of the Slovak Academy of Sciences, Dobrá Voda, Slovak Republic
- Females nulliparous and non-pregnant: Yes
- Age at study initiation: 8 - 12 weeks
- Weight at study initiation: 210g, 210g, 209g, 230g, 235g, 245g
- Fasting period before study: Animals were fasted prior to dosing food but not water was withheld over-night))
- Housing: The animals were housed in plastic cages suspended on stainless steel racks, up to 3 animals per cage, in a room equipped with central air- conditioning.
- Diet (e.g. ad libitum): A standard laboratory food KKZ-P/M (UEFT CEM SAS) was available ad libitum.
- Water (e.g. ad libitum): The animals received tap water for human consumption. Supply of drinking water was unlimited.
- Acclimation period: The animals were acclimated to the condition identical to the condition during the experiment at least 5 days prior to the start of treatment.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): The room temperature was maintained within the range of 22±2 °C.
- Humidity (%): The relative humidity was 55±10 %.
- Photoperiod (hrs dark / hrs light): The light regime was set to a 12-hour light / 12-hour dark cycle.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

other: 96% Ethyl alcohol p.a. diluted to 36% with Aqua pro Injectione

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 2000 mg of the test item
- Amount of vehicle (if gavage): 36% ethanol (3 ml)
- Justification for choice of vehicle: Aqueous or oil solution/suspension/emulsion was not possible to prepare in order to administer proper dose to animals. BTG Pyrolytic Lignin was dissolved in in 96% Ethanol and further diluted with Aqua pro Injectione to the concentration of 36%. Further dilution caused precipitation of tested substance.
- Lot/batch no. (if required): Ethyl alcohol – 12.11.2019; Aqua pro Injectione – 19L1001

CLASS METHOD
- Rationale for the selection of the starting dose: Available information indicated that the test item was likely to be non-toxic regarding acute toxicity therefore we chose a dose of 2000 mg of BTG Pyrolytic Lignin per kg body weight to be used as a starting dose.

Doses:

2000 mg/kg body weight mixed with the vehicle 36% ethanol (3 ml).

No. of animals per sex per dose:

6 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: The animals were observed individually immediately after the administration of the test item and then 0.5, 1, 2 and 4 hours later. Each animal was inspected daily for the next 14 days.
- Frequency of observations and weighing: Individual weights of animals were determined shortly before the test item administration and weekly thereafter.
- Necropsy of survivors performed: All test animals were subjected to gross necropsy
- Other examinations performed: Examinations included external body surface and orifices, the appearance of tissues and organs in the thoracic cavity (trachea, esophagus, heart, aorta, lungs with main stem bronchi, thymus, tracheobronchial lymph node) and in the abdominal cavity (liver, spleen, adrenal glands, kidneys, ovaries, uterus including cervix, urinary bladder, small intestine, large intestine, pancreas, stomach, mesenteric lymph nodes).

Statistics:

not specified

Results and discussion

Effect levels

Key result

Sex:

female

Dose descriptor:

other: Mortality

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality was observed during the study.

Clinical signs:

other: No signs of intoxication, change of health, nor any other adverse reactions during 24 hours and 14-days observation period

Gross pathology:

No visible pathological findings were observed.

Any other information on results incl. tables

Summary results of body weight

Sex	Dose	ID	Body Weight (g)			Body Weight Difference (g)
			Initial	Week 1	Week 2	Week 1 - Initial	Week 2 - Initial	Week 2 – Week 1
Female	2000 mg/kg	1	210	231	237	21	27	6
		2	210	216	228	6	18	12
		3	209	243	254	34	45	11
		4	230	246	258	16	28	12
		5	235	250	262	15	27	12
		6	245	256	271	11	26	15

Necropsy Results

Sex	Dose	ID	Result
Female	2000 mg/kg	1	no findings
		2	no findings
		3	no findings
		4	no findings
		5	no findings
		6	no findings

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The LD50 of the test item is greater than 2000 mg/kg body weight after single oral administration to Wistar rats. No effects were observed at the limit dose of 2000 mg/kg bw.

Executive summary:

The purpose of the study was to evaluate the potential toxic effect of the test item when administered as a single oral dose to Wistar rats.
The procedure according to OECD Guideline 423 Acute Toxic Class (ATC) method was used. Available information indicated that the test item is likely to be non-toxic regarding acute toxicity, therefore, a limit dose of 2000 mg/kg body weight was used as a starting dose. The test item at this dose did not cause death in the next 48 hours and therefore another 3 females were treated at the same dose level. Pyrolytic lignin did not induce signs of intoxication, change of health, nor any other adverse reactions during 14-days observation period. During necropsy it was not observed any macroscopic findings in any of the animals.

It was concluded that the LD50 of the test item Pyrolytic lignin is greater than 2000 mg/kg body weight after single oral administration to Wistar rats.