effects. However, the effects are not disabling and are transient and reversible upon cessation of exposure.
AEGL-2 is the airborne concentration (expressed as ppm or mg/m3) of a substance above which it is predicted that the general population, including susceptible individuals, could experience irreversible or other serious, long-lasting adverse health effects or an impaired ability to escape.
AEGL-3 is the airborne concentration (expressed as ppm or mg/m3) of a substance above which it is predicted that the general population, including susceptible individuals, could experience life-threatening health effects or death.
Airborne concentrations below the AEGL-1 represent exposure concentrations that could produce mild and progressively increasing but transient and nondisabling odor, taste, and sensory irritation or certain asymptomatic, nonsensory effects. With increasing airborne concentrations above each AEGL, there is a progressive increase in the likelihood of occurrence and the severity of effects described for each corresponding AEGL. Although the AEGL values represent threshold concentrations for the general public, including susceptible subpopulations, such as infants, children, the elderly, persons with asthma, and those with other illnesses, it is recognized that individuals, subject to idiosyncratic responses, could experience the effects described at concentrations below the corresponding AEGL.
Chloroacetaldehyde is a colorless, volatile liquid with an acrid, penetrating odor. It evaporates easily and dissolves in water. It is not flammable, but vapor/ air mixtures may be explosive at temperatures above 88°C. Chloroacetaldehyde can exist in combinations of four forms: monomer, monomer hydrate, dimer hydrate, and cyclic trimer. Commercial aqueous solution of chloroacetaldehyde (45%) contains a 50:50 mixture of the monomer and dimer hydrates. Chloroacetaldehyde is predominantly used as a chemical intermediate in the manufacture of 2-aminothiazole and other compounds, in the control of algae, bacteria, and fungi in water, and in a spinning solution of poly β-alanine.
The toxicity database on chloroacetaldehyde is poor. Apart from a brief statement indicating that a concentration of 10 ppm produced lacrimation and nasal irritation in humans, no information was available on human toxicity. Chloroacetaldehyde is known to be a strong corrosive agent. The predominant effect of chloroacetaldehyde in animals is direct, strong irritation of the eyes, nose, and lungs (resulting in pulmonary edema and death), and has a very steep concentration-response relationship. The best studies of these effects are by Dow Chemical Company (1952) and Arts (1987). The first study exposed mice, rats, and guinea pigs to chloroacetaldehyde at several concentrations and exposure duration, ranging from 400 ppm for 6 min to 10 ppm for 7 h. Rats, mice, and guinea pigs were also exposed repeatedly (eight exposures in 10 days) to