At 08:07 AM 7/18/01, you wrote:
>Can anyone help me to find some articles about the stable isotpic methods
>and pollution? It is a research I have to do for a Ph.D.

Any kind of pollution specifically? Here are 2 things I've come across
recently that may fit your bill, depending on your definition of pollution

Pearson, J., et al. (2000) "Traffic exposure increases natural 15N and
heavy metal concentrations in mosses" New Phytol. v 147, 317-326

Fogg, Graham E., et al. (1998) "Spatial variation in nitrogen isotope
values beneath nitrate contamination sources" Ground Water v. 36, No. 3,
418-426

Howard