Hi Johan,
If you mean import from client file, the answer is yes :
As DBA disable option for user or group 'alain' for example :
set option alain.ALLOW_READ_CLIENT_FILE='OFF';
set option alain.ALLOW_WRITE_CLIENT_FILE='OFF';
If alain tries enable options, he receives error :
"Could not execute statement. Only the DBA can set the option 'allow_read_client_file' SQLCODE=-204, ODBC 3 State="42000" Line 1, column 46 You can continue executing or stop. set temporary option ALLOW_READ_CLIENT_FILE='ON'".
For normal load (source file in server's machine), I think no solution but revoke insert privilege.
If you need forbid ALL users to use this factility, you can use server option "-gl DBA".
Regards, Tayeb