Section 1 - CHEMICAL PRODUCT AND COMPANY IDENTIFICATION

PRODUCT NAME

O-TOLIDINE DIHYDROCHLORIDE

NFPA

PRODUCT USE

Used in the manufacture of dyes. Used as stain developer in microscopy.

SYNONYMS

C14-H16-N2.2HCl, "benzidine, 3, 3'-dimethyl-, dihydrochloride", "benzidine, 3, 3'-
dimethyl-, dihydrochloride", "4, 4'-diamino-3, 3'-dimethylbiphenyl dihydrochloride", "4,
4'-diamino-3, 3'-dimethylbiphenyl dihydrochloride", "3, 3'-dimethylbenzidine
dihydrochloride", "3, 3'-dimethylbenzidine dihydrochloride", "3, 3'-dimethylbiphenyl-4,
4'-biphenyldiamine dihydrochloride", "3, 3'-dimethylbiphenyl-4, 4'-biphenyldiamine
dihydrochloride", "2, 3'-dimethylbiphenyl-4, 4'-diamine dihydrochloride", "2, 3'-
dimethylbiphenyl-4, 4'-diamine dihydrochloride"

Section 2 - HAZARDS IDENTIFICATION

CANADIAN WHMIS SYMBOLS

None

EMERGENCY OVERVIEW

RISK

Harmful if swallowed.
May cause CANCER.
Toxic to aquatic organisms, may cause long- term adverse effects in the aquatic
environment.

POTENTIAL HEALTH EFFECTS

ACUTE HEALTH EFFECTS

SWALLOWED

  Accidental ingestion of the material may be harmful; animal experiments indicate that ingestion of less than 150 gram may be fatal or may produce serious damage to the health of the individual.  The substance and/or its metabolites may bind to hemoglobin inhibiting normal uptake of oxygen. This condition, known as "methemoglobinemia", is a form of oxygen starvation (anoxia).  Symptoms include cyanosis (a bluish discoloration skin and mucous membranes) and breathing difficulties. Symptoms may not be evident until several hours after exposure.  At about 15% concentration of blood methemoglobin there is observable cyanosis of the lips, nose and earlobes. Symptoms may be absent although euphoria, flushed face and headache are commonly experienced. At 25-40%, cyanosis is marked but little disability occurs other than that produced on physical exertion. At 40-60%, symptoms include weakness, dizziness, lightheadedness, increasingly severe headache, ataxia, rapid shallow respiration, drowsiness, nausea, vomiting, confusion, lethargy and stupor. Above 60% symptoms include dyspnea, respiratory depression, tachycardia or bradycardia, and convulsions. Levels exceeding 70% may be fatal.  

EYE

  Although the material is not thought to be an irritant, direct contact with the eye may cause transient discomfort characterized by tearing or conjunctival redness (as with windburn). Slight abrasive damage may also result. The material may produce foreign body irritation in certain individuals.  

SKIN

  Skin contact is not thought to produce harmful health effects (as classified using animal models). Systemic harm, however, has been identified following exposure of animals by at least one other route and the material may still produce health damage following entry through wounds, lesions or abrasions. Good hygiene practice requires that exposure be kept to a minimum and that suitable gloves be used in an occupational setting.  Entry into the blood-stream, through, for example, cuts, abrasions or lesions, may produce systemic injury with harmful effects. Examine the skin prior to the use of the material and ensure that any external damage is suitably protected.  

INHALED

  Inhalation of dusts, generated by the material during the course of normal handling, may be damaging to the health of the individual.  The material is not thought to produce respiratory irritation (as classified using animal models). Nevertheless inhalation of dusts, or fume, especially for prolonged periods, may produce respiratory discomfort and occasionally, distress.  

CHRONIC HEALTH EFFECTS

  Long term exposure to high dust concentrations may cause changes in lung function i.e. pneumoconiosis; caused by particles less than 0.5 micron penetrating and remaining in the lung. Prime symptom is breathlessness; lung shadows show on X-ray.  Limited evidence suggests that repeated or long-term occupational exposure may produce cumulative health effects involving organs or biochemical systems.  There is ample evidence that this material can be regarded as being able to cause cancer in humans based on experiments and other information.  Exposure to the material may cause concerns for human fertility, on the basis that similar materials provide some evidence of impaired fertility in the absence of toxic effects, or evidence of impaired fertility occurring at around the same dose levels as other toxic effects, but which are not a secondary non-specific consequence of other toxic effects..  Most arylamines are powerful poisons to the blood-making system. High chronic doses cause congestion of the spleen and tumor formation.  4,4'-dihydroxyphenyl oxide may have effects similar tofemale sex hormones.  o-Tolidine is a urinary metabolite found in workers engaged in the  manufacture of 3,3'-dimethylbenzidine dyes. Human intestinal microflora  are responsible for the initial biotransformation of these dyes. Elevated  risk for cancer of the urinary bladder has been found in workers engaged  in dye manufacture and those exposed to a combination of benzidine and  o-tolidine. Administration of o-tolidine has produced cancer in some  tissues but not in bladder. When introduced by gastric intubation mammary  carcinomas were induced, whilst commercial grade o-tolidine induced  Zymbal gland carcinomas and auditory canal carcinomas following  subcutaneous injection. When administered in drinking water rats showed  benign and malignant neoplasms of the skin, Zymbal's gland, liver, oral  cavity, small and large intestine and lung. male rats exhibited an  increased incidence of benign and malignant neoplasms of the preputial  gland and mesothelium and an increased incidence of brain neoplasms.  Female rats showed benign and malignant neoplasms of the clitoral and  mammary gland and brain neoplasms.