Formaldehyde
Airborne concentrations associated with sensory irritation are above 0.3 to 0.5 ppm, eye irritation
being the most sensitive endpoint. Moderate eye, nose and throat irritation occurs at 2 to 3 ppm.
However some individuals may experience adverse effects such as watery eyes; burning sensations
in the eyes, nose, and throat; coughing; wheezing; nausea; and skin irritation at lower
concentrations.
Sensitization
Studies in Animals
Formaldehyde was tested and found to be a skin sensitizer in numerous tests. The induction with a
5% aqueous solution and challenge with 2 and 4% aqueous solutions, for instance, gave a positive
result in a guinea pig maximization test.
Studies in Human
Skin
The thresholds for elicitation of allergic contact dermatitis in sensitized subjects range from 30
ppm(w/w), aqueous solution, for patch testing to 60 ppm (w/w) for products containing
formaldehyde. A threshold for induction has not been clearly established, but it is estimated to be
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