Background. Phenolformaldehyde resins, especially the para-tertiary-bu
tylphenolformaldehyde resin (PTBP-FR), are widely used in industry and
in numerous materials of everyday use, such as glues, adhesives, or i
nks. They can cause many occupational and nonoccupational cases of der
matitis. Patients and Methods. forty-one patients with positive patch
test results to PTBP-FR were selected for this study, They were patch-
tested with a series of chemically related compounds and cross-reactio
ns were noted. Results. Phenolformaldehyde resin (PF-R) was frequently
positive (65.8%), whereas other compounds gave a much smaller number
of positive results, Cases of occupational exposure (24.4%), location
of the dermatitis (hands were involved in 46.3% of cases), and possibl
e sources of exposure (shoes were the responsible agent in 12.2% of ca
ses) were evaluated. Conclusions. Phenolformaldehyde resins are an imp
ortant cause of contact dermatitis and must be studied chemically and
clinically to improve the prognosis of sensitized patients.