RAYMOND SINGER,
PH.D.
A Professional
Association
36
Alondra Road / Santa Fe, New Mexico / 87505
Alternate office: 180 E.
79th Street / Suite 1-C / New York, N.Y. / 10021
Telephone: (505)
466-1100 / Fax: (505) 466-1101 / E-mail: ray.singer@gmail.com
Singer,
R. (2001). Neurotoxicity evaluation of a new solvent. Archives of Clinical
Neuropsychology, 16 (2001), 697.
Purpose:
To evaluate a case of potential neurotoxicity from a new solvent, Foamflush,
which is composed primarily of gamma butyrolactone and n-methyl pyrrolidone.
Both of these substances are organic solvents. The product
replaced the neurotoxic solvent methylene chloride and is designed to dissolve
urethane foam. Foamflush is one of
70,000 chemicals in commercial use, most of which lack adequate, or any testing,
for potential workplace neurotoxicity. Nevertheless, all organic solvents have
the potential to cause neurotoxicity due to their action of dissolving organic
materials, such as lipids in nervous system tissue, depending upon factors of
exposure (amount, duration, intermittency, co-exposures, etc.), the exposed
(constitution, prior exposures, current health status etc.), the dissolving
strength of the solvent, and its capacity and opportunity to enter the human
body.
Method:
Exposure assessment, neuropsychological testing, personality
assessment
Results:
A woman worked for 3 years on an assembly line manufacturing foam automobile air
filters. She had an almost perfect work attendance record, and was well regarded
by co-workers and supervisors. On two occasions during her last months at this
job, the hosing carrying the solvent, Foamflush, malfunctioned, and she was
enveloped in a solvent mist. Immediate symptoms included headache, nausea, skin
rash, shortness of breath, stomach pain, nervousness, blackouts, hoarseness, and
slowing and slurring of speech. Shortly thereafter, she developed a disorder
similar to Parkinson=s disease, with motor and cognitive dysfunction. She was
diagnosed with extrapyramidal system dysfunction, tremor and headache. Upon
examination 4 years post-exposure, symptoms consistent with permanent
neurotoxicity were found with the Neurotoxicity Screening Survey.
Estimated pre-morbid FSIQ was probably in the average range. Current FSIQ was
1st % (VIQ 2nd %, PIQ 1st %). She had extreme
anxiety and depression on the Beck=s Inventories. Malingering was not found on 4
tests of this variable. Results on the NEO Personality Inventory indicated a
possible Avoidant or Dependent personality disorder, conditions which were
probably latent prior to exposure. Examination of the medical record found no
alternate explanation of her illness.
Conclusion:
Gamma butyrolactone and/or n-methyl pyrrolidone may cause permanent
neurotoxicity in some people, depending upon various factors of exposure, etc..
In general, solvent-workers need to be informed of the potential for neurotoxic
injury from their exposure, and then monitored using repeated neurobehavioral
tests.