Acrylonitrile

Health surveillance data

Administrative data

Endpoint:

health surveillance data

Type of information:

other: review

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Unpublished review of the available data

Data source

Reference

Reference Type:

grey literature

Title:

Unnamed

Year:

2010

Materials and methods

Study type:

other: review

Endpoint addressed:

neurotoxicity

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

Literature review

GLP compliance:

no

Remarks:

: not relevant

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:

occupational

Ethical approval:

not applicable

Details on study design:

Review and critical appraisal of relevant luterature data relating to the neurotoxicity of acrylonitrile.

Results and discussion

Any other information on results incl. tables

Wilson (1944) reports health problems encountered in workers exposed to acrylonitrile in the synthetic rubber industry. Reported symptoms included nausea, vomiting, diarrhoea, weakness, fatigue, headache, nasal irritation and oppressive feeling. Workers were also likely exposed to a number of other compounds used in the manufacture of synthetic rubbers, such as butadiene, styrene, hydrogen peroxide and carbon tetrachloride. The same author (Wilson et al., 1948) reports that workers exposed to acrylonitrile at concentrations of 6-100 ppm for 20-45 minutes had headaches, irritation of mucous membranes and nervous irritability. However potential exposure to multiple chemicals may also have contributed to this symptomatology.

Sakurai et al (1978) studied the effects of acrylonitrile in workers exposed for over 5 years, and in matched controls. Although the authors were very careful in selecting the subjects for this study, the sample sizes in this study are small (three groups of 20 exposed workers; exposure levels of 2.1, 7.4 and 14.1 ppm). No evidence for an effect of acrylonitrile was found, but the possibility of a palpable liver and conjunctival reddening effects cannot be entirely excluded.

 

Muto et al. (1992) report that medical examination failed to detect any health effects attributable to long-term exposure to acrylonitrile at 0.27 and 0.84 ppm, but symptoms of irritation could not be ruled out. Some symptoms such as heaviness in the stomach were reported in the absence of other gastrointestinal symptoms. Eye pain or lacrimation were also seen in one factory; decreased libido, poor memory and reddening of the conjunctiva were reported in another factory. These signs and symptoms were not reported in the other factories and were not considered related to acrylonitrile as the level of exposure was considerably lower than past levels, according to the authors.

 

Kaneko et al. (1992) investigated the relationship between long-term exposure to acrylonitrile and symptoms as measured with a questionnaire (modified Cornell Medical Index) in seven acrylic fibre factories (504 males divided into three exposure groups of 1.8, 7.4 or 14.1 ppm for 5-9 years) and in a reference group of 255 males. The authors conclude that there were no differences between the exposed and referenced groups.

 

Cheng et al. (2004) examined olfactory function in 52 injection-moulding workers exposed to acrylonitrile-butadiene-styrene (ABS) thermal decomposition products (7.3 years at unknown exposure levels) and in 72 control workers. The Connecticut Chemosensory Clinical Research Center method was used to test olfactory functions. Threshold scores were significantly reduced in the exposed workers compared to controls, but they recovered after one night of rest. Due to the concurrent exposure to other respiratory irritants, the authors concluded that it was impossible to speculate on the cause of the lower threshold scores in this study.

 

Rongzhu et al. (2005) examined the neurobehavioral effects in 3 groups of workers exposed to acrylonitrile by inhalation (175 workers from two departments exposed to 0.11 or 0.91 ppm (no personal sampling and with expousre to other substances). The matched control group consisted of 174 unexposed workers. Several psychological tests were used in this study and gave ambiguous data (contradictory results, no relation to exposure duration). Simple reaction time (attention/response speed) and motor steadiness tests showed reduced performance in both exposed groups compared to controls, as well as a duration-related decrease. Among the many tests, several statistically significant differences were flagged, and the multiplicity problem was neither controlled nor addressed. The authors conclude that due to limitations, further studies are needed to determine the presence of a neurotoxic effect.

Applicant's summary and conclusion

Conclusions:

It is concluded that irritation is often reported in human studies, however other reported signs or symptoms were nonspecific (headache, fatigue, weakness). It is noted that olfactory function can be reversibly affected in workers exposed to ABS products for several years, but that no convincing evidence has been provided to support neurobehavioural effects in workers exposed to AN by inhalation at ambient concentrations of 0.91 ppm.

Executive summary:

The author reviews the available health surveillance data relating to the neurotoxicity of acrylonitrile. It is concluded that irritation is often reported in human studies, however other reported signs or symptoms were nonspecific (headache, fatigue, weakness).