Yeah, drew010 is correct.
When you're performing a query that will return more than one result, you have to "fetch" each row, as such. The error in your code, is you're not actually "fetching" the email addresses, so you can't expect to have them in an array.
I'd suggest using the mail command inside the while loop, or, alternatively, build up a variable of the addresses, and use implode outside the loop.
while($row = mysql_fetch_array($result)) {
$emails[] = stripslahes($row["email"]);
}
$addresses = implode(",",$emails);
You can take it from there.
Hope it helps.
Kev.