Dumped but not burned!

Have concern about the amount of aviation fuel that is dumped into the air during flight to reduce the weight on landing gear and as a safety measure to lessen fire risk. Every day airliners worldwide are dumping huge amounts of fuel into the atmosphere.
What happens to it? What is it doing to our health? What is it doing to the Greenhouse? I'm sure that vested interests will say it is safe, that it disapates, etc.
What goes up must come down. On us, on our food, on our water supply. What affect does it have on the ocean and sea life? Think about it, I read that one Plane dumped 83 tonnes of fuel. Multiply this by all the planes in the world and its a major concern. HAVE a NICE DAY!

I don't know what the actual stats are but it's supposed to be only done when the route was shorter than planned or in an emergency landing straight after take off. I can't imagine airlines deliberately overloading their planes with fuel that they know is just going to be dumped before landing - it ain't cheap.

But then I wouldn't be surprised if it was a regular occurrence.

It's supposed to be done at a relatively high altitude so that it has a chance to evaporate before it hits the ground. I do recall something in the papers about it a couple of years ago - some health issue in parts of Sydney someone had connected to the practice. Another reason not to live in a city, they're such unhealthy places...

As I understand it, most of the newer aircraft do not have the ability to dump fuel. They have to burn it. Within the last year or so a flight from LA to NY had a problem. They circled for 3 hours before landing in LA.