Ammonia, anhydrous

Direct observations: clinical cases, poisoning incidents and other

Administrative data

Endpoint:

direct observations: clinical cases, poisoning incidents and other

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Published medical case report

Data source

Reference

Reference Type:

publication

Title:

Laryngeal Sequelae Due to Accidental Inhalation of Anhydrous Ammonia

Author:

Cruz, W., and Bela da Fonseca, M.C.

Year:

2009

Bibliographic source:

Intl. Arch. Otorhinolaryngol., 13(1): 111-116

Materials and methods

Study type:

clinical case study

Endpoint addressed:

acute toxicity: inhalation

Test guideline

Qualifier:

no guideline required

Principles of method if other than guideline:

Case report describing accidental inhalation burns

GLP compliance:

no

Remarks:

published medical case report

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:

Anhydrous ammonia gas

Method

Type of population:

general

Subjects:

Case 1: 26 year old white female
Case 2: 40 year old white female
Case 3: 23 year old white male

Ethical approval:

not applicable

Route of exposure:

inhalation

Reason of exposure:

accidental

Exposure assessment:

not specified

Details on exposure:

A tanker carrying anyhdrous ammonia crashed, falling off a main road in Sao Paulo, the gas leaked along the road and into a nearby neighbourhood. 54 people inhaled the gas and were treated at hospital. The paper reports on 3 cases of dysphonia caused by inhaling the gas.

Examinations:

Three exposure cases were still suffering from dysphonia 90 days after the initial exposure, despite the medical treatment listed below. All three were given an ortorhinolaryngological exam (including vide-laryngoscopy) 90 days after exposure.

Medical treatment:

Initially, patients were treated with antibiotics, corticosteroids, the throat was washed with abundant water, intense washing of the eyes and oxygen therapy.

Results and discussion

Clinical signs:

Dysphonea; chronic laryngitis and dyspnoea

Results of examinations:

Case 1: presented with normal otorhinolaryngological exam, except for the vocal cords that, upon video-laryngoscopy, presented with hyperemia, slight oedema and bilateral leukoplakia. She was medicated with corticosteroids and phonoaudiologic therapy was recommended.
Case 2: tracheostomy was performed and the subject was admitted to hospital for 30 days. The tracheal cannula was removed and the tracheostoma was closed after 60 days, but dysphonia remained. The otorhinolaryngological exam was normal, except for the vocal cords, that in the videolaryngoscopy presented with hyperemia, moderate edema, and granuloma located in the posterior 1/3 of the left vocal cord. She was medicated with corticosteroids and phonoaudiologic therapy was recommended.
Case 3: The otorhinolaryngological exam was normal, except for the vocal cords, that in the video-laryngoscopy presented with hyperemia and adherence of all the anterior and middle third, with bilateral granulomas in the posterior comissure which led to stenosis of the glottis region. He was medicated with corticosteroids and after 60 days the granulomas disappeared and stenosis remained; phonoaudiological therapy was indicated after surgical treatment.

Effectivity of medical treatment:

60 days after examination and treatment, dysphonia was improved and only slight oedema was present in the vocal cords.

Outcome of incidence:

No information given in report

Any other information on results incl. tables

Laryngoscopic examination of patients following accidental anhydrous ammoia inhalation revealed diffuse erythema and oedema of lips, soft palate, posterior wall of the pharynx and epiglottis, up to first, second and third degree burns in the oropharyngeal, hypopharyngeal and laryngeal cavities. After 15 days, there were portions of the soft palate mucosa with fibrin and diffuse oedema with fibrinous exudate in the oropharyngolarynx. After 60 days, the authors observed an improvement of dysphonia and the laryngoscopy revealed a sight vocal cord oedema.

Applicant's summary and conclusion

Conclusions:

Inhalation of anhydrous ammonia caused burns and laryngeal sequelae.

Executive summary:

A tanker truck carrying anhydrous ammonia fell off a highway, and released a dense cloud of anhydrous ammonia gas. Fifty-four people inhaled the gas and after ninety days, three people were still experiencing hoarseness and were examined. The authors assessed three patients with laryngeal sequelae due to anhydrous ammonia inhalation burn. They found a case of hyperemia and oedema, one case of granuloma of the posterior third portion of the left vocal cord, and one case of vocal cord adhesion.

Treatment included corticosteroid medication and phonoaudiological treatment.