[Grammar] Are these sentences correct?

[popri]

Hi, please help with my English.

1)Some studies say that crops grown without using chemicals are safer than that grown with using them.
2)Some studies say that crops grown without using chemicals are safer than the ones grown with using them.

Are both sentences correct?
Is “that (or a demonstrative pronoun)” able to become an antecedent of “grown with using it”?

Thank you.

 

[andrewg927]

I would say "those" instead of "that". Also omit "with". "With" and "without" are not used together like that.

 

[popri]

Thanks for your explanation.

1)Some studies say that crops grown without using chemicals are safer than those grown using them.
2)Some studies say that crops grown without using chemicals are safer than the ones grown with using them.

So, both revised sentences are correct, right?

 

[GoesStation]

Number 1 is correct. Number 2 would be okay if you removed the second using.

 

[popri]

Thank you for my typing mistake.
2)Some studies say that crops grown without using chemicals are safer than the ones grown with them.
or Some studies say that crops grown without using chemicals are safer than the ones grown using them.　Right?

 

[andrewg927]

Yes.

 

[tedmc]

How about: Some studies say that crops grown are without using chemicals are safer?

I thought it is understood that the comparison is made with crops grown with using chemicals.

 

[tzfujimino]

How about: Some studies say that crops grown [STRIKE]are[/STRIKE] without using chemicals are safer?

I thought it is understood that the comparison is made with crops grown with using chemicals.

 

[GoesStation]

How about: Some studies say that crops grown [strike]are[/strike] without using chemicals are safer? :tick:

I thought it is understood that the comparison is made with crops grown [strike]with[/strike] using chemicals.:tick:

See above.