[Softeners in synthetic materials--are they harmful to humans? First indication of genotoxic effect of phthalates].
BACKGROUND
A wide range of phthalate derivatives are added to plastic materials, including PVC, as softeners. Although the possibility that these substances pose a risk to human health continues to be discussed, a definitive answer has yet to be found. In particular, their genotoxic potential has not so far been investigated in human material.


METHODS
The literature is reviewed to provide an overview of the present state of such discussions. We carried out our own in vitro investigations into the genotoxicity of dibutylphthalate (DBP) and diisobutylphthalate (DIBP) in human mucosa with the aid of the alkaline version of single-cell microgel electrophoresis.


RESULTS
Various effects of phthalates have been identified in the animal model, for example, changes in blood count, anti-androgenic or xenoestrogenic effects, proliferation of peroxisomes and progression of liver cell tumors. In humans, elevated phthalate levels following treatment with extracorporeal oxygenation have not been found to have any direct toxic effects. Initial results of our in vitro studies revealed a clear genotoxic potential in human oropharyngeal and nasal mucosa.


CONCLUSIONS
Using suitable test methods, phthalates need further investigation for their health hazard potential in humans. In vitro experiments with two substances of this class involving human mucosa, indicate the possibility of geno-toxic effects.
Kleinsasser
N H
NH
Klinik und Poliklinik für Hals-, Nasen- und Ohrenkranke der Universität München.
Harréus
U A
UA
Münzenrieder
R K
RK
Weissacher
H
H
Kastenbauer
E R
ER
D000818:Animals; D004249:DNA Damage; D005260:Female; D006801:Humans; D008297:Male; D009152:Mutagenicity Tests; D010795:Phthalic Acids / Q000633:toxicity*; D010969:Plastics / Q000633:toxicity*
D010795:Phthalic Acids; D010969:Plastics