Ammonia, anhydrous

Repeated dose toxicity: inhalation

Administrative data

Endpoint:

sub-chronic toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Older published, public domain material. Not a standard test.

Data source

Reference

Reference Type:

publication

Title:

Effects of Atmospheric Ammonia on the Pig

Author:

Stombaugh, D.P., Teague, H.S. and Roller, W.l.

Year:

1969

Bibliographic source:

J. Anim. Sci. 28(6), 844-847

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Assessment of the effects of ammonia exposure in pigs

GLP compliance:

no

Remarks:

: published study, predates GLP

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Ammonia, anhydrous

EC Number:

231-635-3

EC Name:

Ammonia, anhydrous

Cas Number:

7664-41-7

Molecular formula:

H3N

IUPAC Name:

ammonia

Details on test material:

No further details

Test animals

Species:

pig

Strain:

other: Duroc

Sex:

not specified

Details on test animals or test system and environmental conditions:

Two trials were performed. Thirty six Duroc pigs with an average initial weight of 45.3 kg were used in trial 1 and the average initial weight of the 36 pigs in trial 2 was 62.5 kg. Animals were placed in four 2.7 x 4.9 m compartments each possessing its own air tempering unit which maintained a dry bulb temperature of 21.2 ⁰C and a relative humidity of 77% throughout the trials. The pen floors were poured concrete and were cleaned daily to prevent any appreciable increase of ammonia or other gases from waste decomposition.

Administration / exposure

Route of administration:

inhalation

Type of inhalation exposure:

whole body

Vehicle:

other: unchanged (no vehicle)

Details on inhalation exposure:

Ammonia was introduced into three of the four compartments in the supply air ducts. To control introduction, a corrosion resistant pressure regulating valve was mounted on the bulk tank.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Ammonia levels were measured daily using the standard technique described by Goldman and Jacobs (1953). The method consists of bubbling a known quantity of air through dilute sulfiuric acid and back titrating with dilute sodim hydroxide.

Duration of treatment / exposure:

5 week period, continuous exposure to the ammonia levels.

Frequency of treatment:

Continuous exposure to ammonia

Doses / concentrations

Remarks:

Doses / Concentrations:
Concentrations ranging from 31-150 ppm.
Basis:
analytical conc.

No. of animals per sex per dose:

There were 36 animals in trial 1 and 36 animals in trial 2. The sex of the animals is unknown.

Control animals:

no

Details on study design:

Four groups of pigs in each of the two trials were exposed for a 5-week period to ammonia concentrations of approximately 10, 50 , 100 and 150 ppm. Response criteria were feed consumption, growth rate, feed efficiency and results of gross microscopic and bacteriological examination of the respiratory tract. Pigs were weighed at weekly intervals and feed consumption was determined on Monday, wednesday and Friday of each week. At the end of the experimental period, three animals were selected from each compartment of trial 1 and two from each compartment in trial 2 for autopsy.

Positive control:

No positive control

Examinations

Observations and examinations performed and frequency:

Pigs were weighed at weekly intervals and feed consumption was determined on Monday, wednesday and Friday of each week. At the end of the experimental period, three animals were selected from each compartment of trial 1 and two from each compartment in trial 2 for autopsy. The bronchi, lungs and turbinates were examined grossly and tissues from the mid-portion of the ventral turbinate and the cardiac or anterior part of the diaphragmatic lobe of the lung were examined microscopically.

Sacrifice and pathology:

At the end of the experimental period, three animals were selected from each compartment of trial 1 and two from each compartment in trial 2 for autopsy. The bronchi, lungs and turbinates were examined grossly and tissues from the mid-portion of the ventral turbinate and the cardiac or anterior part of the diaphragmatic lobe of the lung were examined microscopically.

Other examinations:

No further examination

Statistics:

None

Results and discussion

Results of examinations

Clinical signs:

effects observed, treatment-related

Mortality:

mortality observed, treatment-related

Body weight and weight changes:

effects observed, treatment-related

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Food efficiency:

no effects observed

Water consumption and compound intake (if drinking water study):

not specified

Ophthalmological findings:

effects observed, treatment-related

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Behaviour (functional findings):

effects observed, treatment-related

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Histopathological findings: neoplastic:

not examined

Details on results:

Ammonia concentration had a highly significant adverse effect upon feed consumption and average daily weight gain. However, there was no significant effect upon efficiency of food conversion. During both trials the high ammonia levels appeared to cause excessive nasal, lacrimal and mouth secretions. This was more pronounced at 100 and 150 ppm than at 50 ppm. Autopsies carried out on three animals showed no significant gross or microscopic differences related to ammonia level. Cultures of Corynebacterium and Pasteurella were obtained from swabs of the ethmoid turbinates from two animals removed from the compartment maintained at 150 ppm and one animal maintained at 100 ppm. There was no evidence of these bacteria in turbinate swabs from other animals.

Effect levels

1

Dose descriptor:

NOEL

Remarks:

5 weeks

Effect level:

61 ppm

Sex:

not specified

2

Dose descriptor:

LOEL

Remarks:

5 weeks

Effect level:

103 ppm

Sex:

not specified

Basis for effect level:

other: coughing and nasal, lacrimal and oral secretions

Target system / organ toxicity

Critical effects observed:

not specified

Any other information on results incl. tables

Other noticable differences in the pigs included increased coughing. A measure of the frequency of the coughing obtained by recording the number of coughs heard while weighing the pigs in each pen revealed that at the higher ammonia concentration (100 and 150 ppm) pigs coughed approximately three times as much as those in the other two compartments. At 50 ppm the frequency of coughing was slightly greater than at the more natural level of ammonia (10 ppm).

Applicant's summary and conclusion

Conclusions:

Ammonia concentrations had a highly significant adverse effect upon food consumption and average daily gain. However, there was no significant effect upon efficiency of feed conversion. Frequency of coughing was increased when the animals were exposed to higher levels of ammonia. Also cultures of Corynebacterium and Pasteurella were obtained from swabs of the ethmoid turbinates from two animals removed from the compartment maintained at 150 ppm and one animal maintained at 100 ppm. There was no evidence of these bacteria in turbinate swabs from other animals.

Executive summary:

Ammonia concentrations had a highly significant adverse effect upon feed consumption and average daily weight gain. However, there was no significant effect upon efficiency of food conversion. During both trials the high ammonia levels appeared to cause excessive nasal, lacrimal and mouth secretions. This was more pronounced at 100 and 150 ppm than at 50 ppm. Autopsies carried out on three animals showed no significant gross or microscopic differences related to ammonia level. Cultures of Corynebacterium and Pasteurella were obtained from swabs of the ethmoid turbinates from two animals removed from the compartment maintained at 150 ppm and one animal maintained at 100 ppm. There was no evidence of these bacteria in turbinate swabs from other animals.