This paper describes a simple and inexpensive pervaporation flow injection (PFI) system for the on-line determination of arsenic in industrial samples based on amperometric detection. The PFI system uses on-line hydride generation for the separation of As(III) from the sample matrix thus substantially reducing matrix interferences associated with "dirty" industrial samples. A method for the speciation of As(III) and As(V) is also described. The PFI system is validated using hydride generation atomic absorption spectrometry. There was no statistically significant difference at the 95% confidence level between the results for the two methods. The proposed PFI method is characterised by a wide analytical concentration range (0.05-60mgL(-1)), a detection limit for As(III) of 1.0microgL(-1) and a sample throughput of 12h(-1).