Guidelines for care & Use of Dry Solvent Stills [Example]

1. Health Hazards of Some Common Chemicals
(From Bowman Gray School of Medicine’s Chemical Waste Disposal: Policies and Procedures, 1985,
pages III 2-6, reprinted with permission)
Some of the more obviously dangerous properties of common classes of chemicals are listed here
as a preliminary source of toxicity information. Physical and health hazards are described, along with
“signs and symptoms associated with exposures to hazardous chemicals used in the laboratory” (OSHA, in
29 CFR 1910.1450). You will not be using all of these chemicals in the undergraduate labs. In fact, the
more dangerous a chemical is, the less likely it will be assigned as a reagent in your lab.
1. “ Acids
Acetic acid is considerably more corrosive to the skin than is generally believed, readily
penetrating the skin producing blisters, dermatitis, and ulcers. Even at room temperature the
vapor is highly irritating to the eyes and to the nose and throat on inhalation.
2. Alcohols
Chromic Acid is a strong oxidizing agent but not a strong acid. It is both poisonous and irritating
to the skin. Precautions should be taken against skin contact with the solid or its solutions and
against inhalation of dust from the solid or of mist from the solutions. Reaction with chlorides
yields chromyl chloride. Chromic acid and chromyl chloride are suspected carcinogens.
Hydrochloric acid fumes are corrosive to tissues on contact.
Hydrofluoric acid is extremely irritating and corrosive to the skin and mucous membranes. It
produces severe skin burns which are slow in healing. Burns must be treated immediately as
tissue necrosis can develop. It is highly toxic by ingestion or inhalation.
Nitric acid is a powerful oxidizing agent. In the oxidation of most organic materials, concentrated
nitric acid will produce dense clouds of highly toxic red or brown oxides of nitrogen. Since
inhalation of these oxides in dangerous quantities produces only a mild irritation of the
respiratory organs, it is possible to inhale a dangerous concentration without much discomfort or
apparent injury.
Picric acid is rapidly absorbed through the unbroken skin and even more rapidly through wounds,
leading to headache, fever, and insomnia. Exposure to the dust of picric acid may cause irritation
to the nose and throat and especially of the eyes, leading to ulceration of the cornea. It is also
hazardous due to its explosive properties.
Sulfuric acid (concentrated) chars and destroys plant or animal tissue because of its avidity for
water, which it removes from organic material with which it comes in contact. The fumes are
extremely irritating both to the skin and to the mucous membranes.
Phosphorus halides and oxy-halides are fuming liquids or solids which decompose rapidly in the
presence of water or moist air to form hydrochloric, phosphorous, or phosphoric acids. The
vapors are strongly irritating to the skin, mucous membranes, and respiratory system.
Phenol (carbolic acid) is readily absorbed through the intact skin. Liquid phenol in contact with
skin produces a tingling sensation followed by a loss of feeling. The skin becomes white and
wrinkled and later turns dark brown and sloughs off. This is not a true corrosive action, but is a
local gangrene caused by destruction of the blood supply to the affected area.
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