OSHA Hazard Information Bulletins Health Hazard Information Alert Regarding Thixon 511-T.
OSHA Safety and Health Information Bulletins - Table of Contents
- Information Date: 19860722
- Record Type: Hazard Information Bulletin
- Subject: Health Hazard Information Alert Regarding Thixon 511-T.
July 22, 1986
MEMORANDUM FOR REGIONAL ADMINISTRATORS
THRU: |
JOHN MILES Director Directorate of Field Operations |
|
| EDWARD BAIER Director Directorate of Technical Support |
|
FROM: |
RALPH YODAIKEN Director Office of Occupational Medicine |
|
SUBJECT: |
Health Hazard Information Alert Regarding Thixon 511-T |
On April 23, 1986, five rubber molding workers employed at Barr Rubber
Corporation, Sandusky, Ohio were hospitalized for methemoglobinemia.
Investigation by NIOSH found the cause to be from the contamination of an
adhesive called Thixon 511-T with dinitrobenzene. The contaminant was traced
to a curing agent which is supplied by Sandoz Chemical Corporation,
Charlotte, North Carolina for the production Thixon 511-T. On May 28, Dayton
Chenucak Division of the Whittaker Corporation, the manufacturers of Thixon
511-T, recalled Lots #6171 and #5231 because of dinitrobenzene contamination.
Lot samples of the curing agent are not routinely retained by Sandoz for
future chemical analysis. It is, therefore, possible that other lot numbers
are also contaminated with dinitrobenzene.
Thixon 511-T is a solvent-borne adhesive which was being used by Barr Rubber
to bond metal studs onto automotive rubber bumper strips.
Dinitrobenzene is (normally) used in the preparation of dyes and dye
intermediates, as a polymerization inhibitor in the plastics industry, and as
an explosive. The current OSHA standard for dinitrobenzene is 1 milligram
per cubic meter of air (1 mg/m3) for an eight hour TWA with a "skin"
notation. The American Conference of Governmental Industrial Hygienists
(ACGIH) has recommended a Threshold Limit Value exactly the same as the OSHA
PEL.
Dinitrobenzene causes methemoglobinemia which prevents oxygen uptake in the
blood and may, in rare cases, be fatal. The symptoms of acute exposure
include cyanosis, a blue coloration of the lips and fingernails, and headache
when the methemoglobin level exceeds 15 percent of the total hemoglobin.
Breathlessness upon exertion, weakness, nausea and vomiting occur with levels
above 40 percent. Levels greater than 70 percent can cause stupor, coma, and
possibly death. Symptoms may be aggravated by alcohol and certain
susceptible individuals are more likely to develop methemoglobinemia.
Chronic exposure is associated with anemia, reduced vision and possibly liver
damage.
Because methemoglobinemia can be asymptomatic, any worker exposed to Thixon
511-T should have a complete medical examination. Special attention should
be given to:
(1) A present or past account of symptoms suggesting
methemoglobinemia.
(2) A yellow discoloration to the skin from contact with
dinitrobenzene and cyanosis (blue coloration of lips and
fingernails).
(3) Blood studies including a complete blood count, liver enzymes,
and a post-shift methemoglobin concentration.
Treatment is necessary for severe mehtemoglobinemia which requires
hospitalization for supportive care and intravenous administration of
methylene blue.
OSHA Safety and Health Information Bulletins - Table of Contents |
|