Human systemic exposure to [14C]-paraphenylenediamine-containing oxidative hair dyes: Absorption, kinetics, metabolism, excretion and safety assessment

Systemic exposure was measured in humans after hair dyeing with oxidative hair dyes containing 2.0% (A) or 1.0% (B) [14C]-p-phenylenediamine (PPD). Hair was dyed, rinsed, dried, clipped and shaved; blood and urine samples were collected for 48 hours after application. [14C] was measured in all materials, rinsing water, hair, plasma, urine and...

Occupational exposure of hairdressers to [14C]-para-phenylenediamine-containing oxidative hair dyes: A mass balance study

We monitored the exposure of hairdressers to oxidative hair dyes for 6 working days under controlled conditions. Eighteen professional hairdressers (3/day) coloured hairdresser's training heads bearing natural human hair (hair length: approximately 30 cm) for 6 h/working day with a dark-shade oxidative hair dye containing 2% [14C]-para...

Repeated topical treatment, in contrast to single oral doses, with Vitamin A-containing preparations does not affect plasma concentrations of retinol, retinyl esters or retinoic acids in female subjects of child-bearing age

Background: Vitamin A is widely used in cosmetic preparations. Given that oral Vitamin A and its metabolites present a potential reproductive risk, the present study investigated the effect of topical Vitamin A on human endogenous plasma levels of Vitamin A and its metabolites. Methods: Two groups of 14 female volunteers of child-bearing age...

Human systemic exposure to a [14C]-para-phenylenediamine- containing oxidative hair dye and correlation with in vitro percutaneous absorption in human or pig skin

We investigated the absorption of a commercial [14C]-PPD- containing oxidative dark-shade hair dye in human volunteers as well as in vitro using human or pig ear skin. The hair of eight male volunteers was cut to a standard length, dyed, washed, dried, clipped and collected. Hair, washing water, materials used in the study and a 24-h scalp wash...

Urinary acetylated metabolites and N-acetyltransferase-2 genotype in human subjects treated with a para-phenylenediamine-containing oxidative hair dye

In the organism of mammals, important detoxification pathways of arylamines are catalysed by N-acetyltransferase 2 (NAT2). A recent case-control epidemiology study suggested that human NAT2 slow acetylators exposed to oxidative hair dyes may be at greater risk to develop bladder cancer. We therefore profiled urinary [14C]-metabolites and NAT2...

Safety assessment of a P-phenylenediamine (PPD) containing permanent hairdye: A [14C]-radiolabelled mass balance study in human volunteers

Safety assessment of a p-phenylenediamine (PPD) containing permanent hair-dye: A [14C]-radiolabelled mass balance study in human volunteers