if your god created a perfect world, for humans, why is 78% of the atmosphere poisonous to humans, ?

Salt is a natural cleaning agent. That would make perfect sense to have so much cleaning agent in a world full of sinful destroyers.

And there is tons of drinking water everywhere. For those that have tried to attack the Lord, your attack is among the stupidest attempts I have ever seen. Laughably idiotic.

I am an atheist, but I still think this question is ridiculous. Nitrogen is not poisonous to humans.

Quick, everyone move to Mars.

How can air be poisonous if we breathe it? We would die if the air was 100% oxygen

Don't breathe!

So God should kill all fish in the ocean so we can magically become fresh water, and He should make us grow fins and gills?

... you.. didn't exactly think this out before asking..  did you?

Nitrogen is not poisonous. There are bacteria that turn nitrogen into fertilizer.

If 78% of the atmosphere was poisonous, we would be dead.

The bible doesnt say the world is perfect duh.

If the atmosphere was full of oxygen everything would burn down.

Sooo.....here's how it happened, according to the completely accurate, amazing book called The Bible.

God created the planet perfect. Oh yes, it was AMAZING! Except....he gave us " free will " which include the ABILITY to defy him (which to me doesn't sound so perfect, but still 😉). He then said "DONT USE THAT FREE WILL, OR ELSE!"

So that crazy Eve, she goes off and uses her free will. This is the point where a truly magical transformation took place.

SATAN took over, completely thwarting God's perfect plan, and created all kinds of shite that wasn't there before....sickness, death, volcanoes, mosquitoes, etc. Woah that dude is powerful!

So as you see, SATAN is the one who salted the water and reduced the O2 levels in the atmosphere. GOD had nothing to do with it, and was completely powerless to fix it!

Nobody - not even God - ever claimed the world was perfect. Merely "very good".

Yet, we're still kicking, ain't we?

Our existence thrives on conflict and adversity.  What would drive us to survive, if there were no danger or threat to our existence?  The entire universe is sustained by an endless succession of violent collisions, eruptions, explosions and implosions; life on earth is no exception, especially in the human domain.  

Our world is expressed as "variety" and "diversity", which is suitable for our capacity 'to choose'; hence 'freewill'.  This realm is "purgatorial", allowing the possibility for "positivity, negativity, and neutrality", as potential outcomes, and available options to select from.  

Freewill is what allows us to operate outside "divine bounds", but not without consequences.  Without freewill, we'd all remain stuck on the levels we start out on, with no chance of progress.  This realm allows human the maximum opportunity for advancement, based on our abilities, and limitations.

Out of His Unconditional Love, it is God's Will that we have freewill, so that we may choose Him on our own; which demonstrates that The Lord does not rule by force.  Love that has to be "forced" cannot be 'Love' at all. Thus, God does not interfere with freewill without our consent, and rob us of the opportunity to choose for ourselves.  

All is 'perfect', if not, 'perfectly imperfect', because of a 'Perfect God'.

God did create a perfect world , man screwed it all up.. just to let you know there is only one God and he's your's also,,one day soon your going to meet him,try telling him he's not your's and see where it gets you..

ask god on judgement day

According to the Bible
God created the Earth to be inhabited.
It does not teach: to be inhabited specifically by humans!

Percentage-wise, extremely little of the atmosphere is poisonous to humans.

71% of the planet's surface is undrinkable water because that water contains a salt content that too high for human consumption.

hmm...
Why are you all the way up there?

Man did, made,  as you ask of!  
If man had never come, neither would these problems! 
In 1950 the Odds for a child to get Cancers was at Zero Percent!  Adults was three percent and most of then smoked.  By 2001 the odds of getting Cancers was at 112! All caused by Man-made things!