TY - JOUR
T1 - Dermal uptake and percutaneous penetration of organophosphate esters in a human skin ex vivo model
AU - Frederiksen, Marie
AU - Stapleton, Heather M.
AU - Vorkamp, Katrin
AU - Webster, Thomas F.
AU - Jensen, Niels Martin
AU - Sørensen, Jens Ahm
AU - Nielsen, Flemming
AU - Knudsen, Lisbeth E.
AU - Sørensen, Lars S.
AU - Clausen, Per Axel
AU - Nielsen, Jesper Baunsøe
PY - 2018
Y1 - 2018
N2 - Organophosphate esters (OPEs) are used as flame retardants, plasticizers, and as hydraulic fluids. They are present in indoor environments in high concentrations compared with other flame retardants, and human exposure is ubiquitous. In this study we provide data for estimating dermal uptake for eight OPEs and ranking in OPEs risk assessment. Dermal uptake and percutaneous penetration of the OPEs were studied in a Franz diffusion cell system using human skin dosed with a mixture of OPEs in an ethanol:toluene (4:1) solution. Large variation in penetration profiles was observed between the OPEs. The chlorinated OPEs tris(2-chloroisopropyl) phosphate (TCIPP), and in particular tris(2-chloroethyl) phosphate (TCEP), penetrated the skin quite rapidly while tris(1,3-dichlor-2-propyl) phosphate (TDCIPP) and triphenyl phosphate (TPHP) tended to build up in the skin tissue and only smaller amounts permeated through the skin. For tris(isobutyl) phosphate (TIBP), tris(n-butyl) phosphate (TNBP), and tris(methylphenyl) phosphate (TMPP) the mass balance was not stable over time indicating possible degradation during the experimental period of 72 h. The rates at which OPEs permeated through the skin decreasedin the order TCEP > TCIPP >= TBOEP >TIBP >= TNBP > TDCIPP > TPHP> TMPP. Generally, the permeation coefficient, k(p), decreased with increasing log K-ow, whereas lag time and skin deposition increased with log K-ow. The present data indicate that dermal uptake is a non-negligible human exposure pathway for the majority of the studied OPEs. (C) 2018 Elsevier Ltd. All rights reserved.
AB - Organophosphate esters (OPEs) are used as flame retardants, plasticizers, and as hydraulic fluids. They are present in indoor environments in high concentrations compared with other flame retardants, and human exposure is ubiquitous. In this study we provide data for estimating dermal uptake for eight OPEs and ranking in OPEs risk assessment. Dermal uptake and percutaneous penetration of the OPEs were studied in a Franz diffusion cell system using human skin dosed with a mixture of OPEs in an ethanol:toluene (4:1) solution. Large variation in penetration profiles was observed between the OPEs. The chlorinated OPEs tris(2-chloroisopropyl) phosphate (TCIPP), and in particular tris(2-chloroethyl) phosphate (TCEP), penetrated the skin quite rapidly while tris(1,3-dichlor-2-propyl) phosphate (TDCIPP) and triphenyl phosphate (TPHP) tended to build up in the skin tissue and only smaller amounts permeated through the skin. For tris(isobutyl) phosphate (TIBP), tris(n-butyl) phosphate (TNBP), and tris(methylphenyl) phosphate (TMPP) the mass balance was not stable over time indicating possible degradation during the experimental period of 72 h. The rates at which OPEs permeated through the skin decreasedin the order TCEP > TCIPP >= TBOEP >TIBP >= TNBP > TDCIPP > TPHP> TMPP. Generally, the permeation coefficient, k(p), decreased with increasing log K-ow, whereas lag time and skin deposition increased with log K-ow. The present data indicate that dermal uptake is a non-negligible human exposure pathway for the majority of the studied OPEs. (C) 2018 Elsevier Ltd. All rights reserved.
KW - PFR
KW - OPFR
KW - OPE
KW - Flame retardants
KW - Plasticizers
KW - Human exposure
U2 - 10.1016/j.chemosphere.2018.01.032
DO - 10.1016/j.chemosphere.2018.01.032
M3 - Journal article
C2 - 29353672
SN - 0045-6535
VL - 197
SP - 185
EP - 192
JO - Chemosphere
JF - Chemosphere
ER -