Acrylonitrile

Direct observations: clinical cases, poisoning incidents and other

Administrative data

Endpoint:

direct observations: clinical cases, poisoning incidents and other

Type of information:

other: review article

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Published review of human poisoning incidents

Data source

Reference

Reference Type:

review article or handbook

Title:

Unnamed

Year:

2004

Materials and methods

Study type:

poisoning incident

Endpoint addressed:

acute toxicity: inhalation

acute toxicity: dermal

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Review of poisoning incidents in humans

GLP compliance:

no

Remarks:

not applicable

Test material

Test material information

Constituent 1

Reference substance name:

Acrylonitrile

EC Number:

203-466-5

EC Name:

Acrylonitrile

Cas Number:

107-13-1

Molecular formula:

C3H3N

IUPAC Name:

prop-2-enenitrile

Method

Type of population:

general

occupational

Subjects:

The review discusses several acrylonitrile poisoning incidents: worker poisoningc and accidental poisoning of children.

Ethical approval:

not applicable

Remarks:

review of accidental poisoning incidents

Route of exposure:

dermal

inhalation

Reason of exposure:

accidental

Exposure assessment:

not specified

Details on exposure:

There were several reported cases: workers exposed to low acrylonitrile concentrations (> 5ppm equivalent to 11 mg/m³), workers in a synthetic rubber manufacturing plant exposed to acrylonitrile vapour at levels of 16 to 100 ppm (35 to 219 mg/m³) for 20 to 45 minutes, and acute inhalation up to 15 minutes.

Examinations:

Various physiological examinations were carried out.

Medical treatment:

In the case of the 24 year old sprayed whilst unloading acrylonitrile from a ship: doctors administered 15 antidotal treatments against cyanide poisonging, and three baths.

Results and discussion

Clinical signs:

Various including local irritation, headaches, vertigo, vomiting, tremors, convulsions. See 'remarks on results'.

Results of examinations:

Examinations not reported.

Effectivity of medical treatment:

In the case of the 24 year old male sprayed with liquid acrylonitrile, 15 antidotal treatments against cyanide poisoning were administered along with three full baths to remove the chemical. The man survived the incident.

Outcome of incidence:

Various, see remarks on results.

Any other information on results incl. tables

Inhalation exposure

Workers exposed to low acrylonitrile vapour concentrations suffered from local effects such as irritation of the eyes, nose, throat and respiratory tract, headaches, vertigo and limb weakness (> 5 ppm). Slight liver enlargement and jaundice have also been reported. Exposure to concentrations of 16 to 100 ppm for 20 to 45 minutes resulted in mucous membrane irritation, headaches, nausea, feelings of apprehension and nervous irritability. Low-grade anaemia, leucocytosis, kidney irritation and mild jaundice were also apparent, but these effects subsided with exposure cessation. In 16 cases of acute inhalation of acrylonitrile fumes by workers, nausea, vomiting headache and vertigo appeared within 5-15 minutes, none of the workers required hospitalisation.

Exposures to higher concentrations have resulted in tremors, convulsions, unconsciousness, respiratory and cardiac arrest, and death. Exposure was fatal in the case of a 3 year old girl who slept overnight in a room recently sprayed with an acrylonitrile-based fumigant. Respiratory malfunction, lip cyanosis and tachycardia were among the symptoms described. Five adults who spent the night and much of the day in a room fumigated with an acrylonitrile based product complained only of eye irritation. The EU RAR reports that there have been several other cases of death in children, where adults only suffered mild irritation.

Dermal exposure

A 10 year old girl died after her scalp had been treated for lice with an insecticide formulation containing acrylonitrile (Ventox). The girl had impetigo and resultant widespread scratches on the skin of her scalp, which could have led to increased absorption of acrylonitrile.

Following exposure to acrylonitrile as a liquid or vapour, local effects such as blisters on the skin and irritation of the mucous membranes and upper respiratory tract was reported. Clinical signs seen a 24 year old man sprayed in the face, eyes and body with liquid acrylonitrile were; dizziness, flushing, nausea and vomiting occurring within 30 minutes of exposure, followed by generalised erythema together with a mild conjunctivitis. The victim subsequently suffered hallucinations and convulsions. There were recurrent signs of cyanide poisoning over a 72 hour period, suggesting that the acrylonitrile (or a metabolite) was stored in tissues, or was slowly absorbed from the skin (or possibly the gastrointestinal tract as it is possible the man swallowed some of the chemical). The patient was thoroughly bathed three times, so the likelihood that deposits on the skin played a role in recurrent bouts of symptoms was remote, and indicated dermal absorption as the possible primary route of entry.

Applicant's summary and conclusion

Executive summary:

The observations of accidental poisoning incidents indicate that acrylonitrile is toxic by the oral, dermal and inhalation routes, that it causes neurotoxic effects (which can be due both to acrylonitrile itself and to the release of cyanide), and that exposure in children is often fatal.