thanks but im not in the USA and in the UAE , you cant find a lot of autocare products !! the only pones ive found here so far are armour all ..

bmw dealers actually carry break dust repellants here in Canada. Ask the dealer for it

What I see on your pics is the tire dressing overspray, which attracts the dust... When you spray your tires to look 'wet', make sure you wipe off the overspray from the rims ! And dont spray too much !

Simple solution? If it bugs ya Wash em. Takes 10 minutes to do them all if all you want to do is get the dust off. No more than 10 minutes a wheel if you want a really great job including the inside of the wheels.

Yes, use a polymer base wax "synthetic" Zaino is good. Then you can top coat with the brand "Wheel Wax" That's what I do.

thats right but the wheel dressing i use says on the instructions "do not wipe , any dripping on the rims will dry alone"

Hmm, it appears they lied. So the question is, which is more important to you, having shiny tires or not having pond scum on your rims?

shiny wheels :P

Another idea that I've only had the patience to try once in the 25 years I've owned these cars is to clean & wax the whole wheel, inside & out.

My guess from your pictures is the rain released brake from the other side of the wheels & it slung onto the front.

Even just shooting the water hose on the back of the wheels will get rid of some of the build up.