A screening procedure for total N-nitroso contaminants in personal care products: results of collaborative studies undertaken by a CTPA Working Group.
Synopsis A modified procedure for the determination of total N-nitroso compounds in personal care products was evaluated in collaborative studies organized through the UK Cosmetic Toiletry and Perfumery Association (CTPA). The method offers a true 'totals'determination in that a solution of the whole sample is analysed. Samples are dissolved/suspended in water or aqueous THF, and nitrite/nitrite ester interferences are removed by prior treatment with sulphamic acid. The treated test solution is denitrosated in a single reaction with HBr/acetic acid, in refluxing n-propyl acetate, and 'total'N-nitroso compounds are determined in a chemiluminescence reaction of the released nitric oxide with ozone. The use of a propyl acetate denitrosation solvent and of higher concentrations of HBr have improved both the sensitivity (routine limit of determination at 10 mugkg(-1)) and water tolerance of the method. The method was shown to recover N-nitrosamines quantitatively, and to be sufficiently repeatable and reproducible to be used as a screening technique for N-nitroso compounds in personal care products.
Challis
B C
BC
Open University, Walton Hall, Milton Keynes MK76AA, UK.
Colling
J
J
Cromie
D D
DD
Guthrie
W G
WG
Pollock
J R
JR
Taylor
P
P
Telling
G M
GM
Wallace
L
L