specific swap partitions for multiple debian distros in single computer

I'm trying to setup a computer with three debian instances (wheezy, jessie and sid), I've created / and swap partitions for each debian instance, during the installation I did specify which swap partition to use for each instance, and I did verify that the other partitions were configured as "do not use this partition", but when running jessie I see the three swap partitions are active

$ swapon -s
Filename                Type        Size    Used    Priority
/dev/sda10                              partition   7812092 0   -1
/dev/sda12                              partition   7812092 0   -2
/dev/sda8                               partition   8191996 0   -3

my /etc/fstab file only refers to one of them

$ cat /etc/fstab 
UUID=197fd69d-285e-4fec-6d5d-498d4d4b92a2 /               ext4    errors=remount-ro 0       1
UUID=562B-713C  /boot/efi       vfat    defaults        0       1
# swap was on /dev/sda12 during installation
UUID=7e958357-a446-4a32-7c06-81f6751fdab6 none            swap    sw              0       0
/dev/sdb1       /media/usb0     auto    rw,user,noauto  0       0

I know I can swapoff the swap partitions corresponding to the other debian instances, and it could be done in a @reboot entry of cron, but I don't like that, to prevent data loss I would prefer them not to be touched at all. Then the question is: how do I tell debian not to use some specific swap partition?