Can salt-based water softeners be harmful to us ...

Your, most water softeners have a tank filled with beads, like marbels. A small electric charge causes the beads to attract and hold hard water minerals such as iron and maganeese particles. After these beads collect their limit of hard water deposits they have to be cleaned. They are cleaned with a solution of SALT WATER". That is all the salt pellets do. After the salt water mixture cleans the beads it is flushed away. Then, the salt mixture is re-flushed again so that only a small trace of salt is left on the tank pellets. It is a very, very small amount of salt left in the tank. So little that you cannot taste or smell it. It is unlikely that your skin could be that sensitive to salt without sensititvy to other chemicials. Older water softeners used a timer to flush the tanks each night while we were asleep, with a timer. Newer units have a detector that constantly anaylizes the water and flushes only when it's needed. That is why they use less salt. To stop your swelling, try this.. DON"T USE THE CHEAPER ROCK SALT. Use more expensive $5.00 a bag pellets. Check to see if your water softener is set correctly. Your cities or countys website publishes the water hardness levels. Set your softener to the cities published levels. A iron rating of 10 or less means you already have soft water. If you live in the country and have "well water",your iron rating could be 30 or more. Check you operation manual that came with the unit to see how to adjust your water softener correctly. If your setting are correct, set your conditeners switch to manual clean now and listen to see if you hear it working. If it is working by the sound, contact the city government to see if they are currently flushing the water system. It sound like it's an ajustment thing. Perhaps an allergy to salt?

I have had swelling in my legs  as well and I cannot figure where else the swelling can come from let me know what else you find out? leilanirodriguez@comcast.net

Yes

Water softeners put salt into bathing and drinking water and after years of bathing and drinking this adds up into our systems.   Many scientist have conducted studies to show serious harm that water softeners do to our bodies.  The 2004 World Health Organization did a report on naturally soft water and it showed an increase in morbidity, heart problems, strokes and osteoperosis to name a few.  It also attributes to child birth defects.  This is naturally soft water, that doesn't even have the salt contamination that water softeners induce.  Hope this helps!

Can the debris and filmy substance that sometime show up in the salt water tank in my wter softener contaimiante the water that flows through the beaded tank in my sofener system and to the tap in my house?

The JEFF72 explaines it is correct, but if the machine is NOT working properly,or is not properly set up, there WILL be salt left in the water going into the house that YOU WILL taste.The machine is not set up properly!!.There should NOT be any salt in the home H2O [water] because it is a chemical process as JEFF72 writes.I happen to own a "RAINSOFT" water softener and they are very expensive ($125~$145 per ADJUSTMENT VISIT) & I have to wait a WHILE (not every year) for the "adjustments" One time the "RAINSOFT" guy came over and charged $65 for a $2.45 PLASTIC gear that was split.I found the price of the gear after the repair.
They have a monopoly on stuff like that. by the way, don't call them a plead bargen or ask them if they can help you over the phone, they won't they want the home visit

Baudelaire, my wife and I both suffered similar swelling almost immediately after moving to our home 3 years ago, with built-in salt-based water softener. The "reaction" is not from skin being exposed to salt. It is a cardiovascular circulation and water-retention problem from DRINKING it. My wife and I are both healthy, athletic people, in good shape and 50 yrs old. It took us the longest time to figure out the problem, as we both would notice swollen ankles in the evening when we settled down for the night. I am a biologist, and it still didn't occur to me that our tap water was the problem, until one day the system's backflush malfunctioned due to a power outage, and we made a pot of coffee that was terribly salty. I started doing research on the salt-based systems, and talked to doctors about it. The culprit became obvious. Even when the system is normally working correctly, the increase in our salt intake is significant. As soon as we switched to a jug bottle of spring water for drinking, the swollen ankles went away.

While jeff72's response is technically correct about how most salt-based water softeners function, to suggest that the trace amounts of sodium chloride in the water is harmless is medically inaccurate. Generally, calcium and magnesium ions are the target of these softeners, as they make up what is called "hard" water. These metals are actually GOOD for us, but bad for pipes and appliances though. The salt softener replaces two good, healthy metals with a BAD, unhealthy molecule which is "salt". Softened water from a salt-based water softener is not recommended for drinking, watering houseplants, lawns and gardens due to its sodium content.  There are many health risks associated with sodium intake.   People on restricted sodium intake diets should account for increased levels of sodium in softened water.  Your family physician should be consulted.  Sodium intake from softened water can be avoided by leaving one kitchen tap un-softened for drinking and cooking. Not only that, but water used in recharging a water softener may over load or reduce the effectiveness of small septic or sewer systems. 

Hope that helps!

The real health concerns are from intake of sodium chloride, and not sodium bicarbonate that results from softening water. You can read more here:

How Water Softeners Work and Salt-Free Water Softeners