PRINCIPLES OF TOXICOLOGY

or now are found in common household products and, thus, poisonings may occur in children. In
addition to ingestion in those cases, aspiration into the lungs may occur, causing chemical pneumonitis
that may complicate treatment.
Many of the adverse effects attributed to solvents are rather nonspecific, and the symptomology of
any particular unknown solvent poisoning often provides few clues to the specific solvent in question.
Acute overexposure to organic solvents initially may produce a generalized “chemical malaise” with
a wide range of subjective complaints. It also may produce temporal changes in effects that appear
contradictory (e.g., euphoria, narcosis). Therefore, initial treatment often is symptomatic with regard
to the systemic toxicity, coupled with measures designed to limit further systemic absorption.
To illustrate the generally nonspecific nature of solvent intoxication and the related problems that
may be faced by the health specialist in attempting to diagnose uncharacterized exposure situations,
acute symptoms are described below for a few common agents. It should be noted that, in contrast to
the acute effects, the effects of chronic exposure to these agents may differ dramatically, as discussed
in other sections of this chapter.
• Benzene—euphoria, excitement, headache, vertigo, dizziness, nausea, vomiting, irritability,
narcosis, coma, death
• Carbon tetrachloride—conjunctivitis, headache, dizziness, nausea, vomiting, abdominal
cramps, nervousness, narcosis, coma, death
• Methanol (wood alcohol)—euphoria, conjunctivitis, decreased visual acuity, headache,
dizziness, nausea, vomiting, abdominal cramps, sweating, weakness, bronchitis, narcosis,
delirium, blindness, coma, death
16.3 TOXIC PROPERTIES OF REPRESENTATIVE ALIPHATIC ORGANIC SOLVENTS
Saturated Aliphatic Solvents: CnH2n+2
Alkanes
16.3 TOXIC PROPERTIES OF REPRESENTATIVE ALIPHATIC ORGANIC SOLVENTS 377
The chemical class known as the saturated aliphatic hydrocarbons, or alkanes (also termed paraffins)
have many members and generally rank among the least potentially toxic solvents when acute effects
are considered. This group represents the straight-chain or branched hydrocarbons with no multiple
bonds. The vapors of these solvents are mildly irritating to mucous membranes at the high concentrations
that are required to induce their relatively weak anesthetic properties. The four chemicals in this
series with the lowest-molecular-weight (methane, ethane, propane, butane) are gases with negligible
toxicity and their hazardous nature is limited almost entirely to flammability, explosivity, and basic
asphyxiant potential.
The higher molecular weight members of this class are liquids and have some CNS-depressant,
neurotoxic, and irritant properties, but this is primarily a concern of the lighter, more volatile fluid
compounds in this series (i.e., pentane, hexane, heptane, octane, nonane). The liquid paraffins,
beginning with the 10-carbon compound decane, are fat solvents and primary irritants capable of
dermal irritation and dermatitis following repeated, prolonged or intense contact.
The symptoms of acute poisoning by this group are similar to those previously described as
generally present in solvent intoxication (i.e., nausea, vomiting, cough, pulmonary irritation, vertigo
or dizziness, slow and shallow respiration, narcosis, coma, convulsions, and death) with the severity
of the symptoms dependent upon the magnitude and duration of exposure. Accidental ingestion of
large amounts (exceeding several ounces, or about 1–2 mL/kg body weight) may produce systemic
toxicity. If less than 1–2 mL/kg is ingested, a cathartic, used in conjunction with activated charcoal to
limit absorption, is the therapeutic approach. In either situation, aspiration of the solvent into the lungs
is the initial primary concern from a medical perspective. Low-viscosity hydrocarbons attract particular