You can easily retrieve the required solvent toxicity information from internet sites; from the solvent's 'Material Safety Data Sheet' or 'Safety Data Sheet', usually available at the internet after the several commercial brands that supply those solvents; or from solvent related or chemical safety related reference literature.

http://www.atsdr.cdc.gov/substances/index.asp

http://www.cdc.gov/niosh/npg/

http://www.fda.gov/default.htm

http://www2.epa.gov/saferchoice/safer-ingredients

Dear Mr. Sudipta,

Actually, both solvents are toxic for its use in scaffolds. However, I would recommend to use DCM because it is easy to eliminate from the final material.  As you donot mention the material that you would like to process is hard to advice you whether the size will increase/decrease with the solvent polarity. good luck

Dear Gloria Huerta Angeles Madam, I am using PCL and PLA as polymer for making scaffold by near field electrospinning. Thanks for your advice. I will be grateful to you if you advice more.

With regards to last post, I would like to mention that the cyclic ethers tetrahydrofuran (THF) or 1,4-dioxane can substitute for dimethylformamide (DMF) as water-miscible solvents for a polycaprlactone (PCL) / poly(lactic acid) (PLA) mixture or blend. 

Thank you Sir Carlos Araujo Queiroz. I have a question to you that is there any effect of solvent on the diameter of electrospun fiber?

With regards to last post, please check: J.M. Gluck; "Electrospun Nanofibrous Poly(ε-caprolactone) (PCL) Scaffolds for Liver Tissue Engineering", MSc. Thesis, North Carolina State University, 2007.

http://repository.lib.ncsu.edu/ir/bitstream/1840.16/2269/1/etd.pdf

Thank you sir Carlos.

Depends on the crosslinking of your PCL or PLA.  DCM in general make polymers swell better than DMF and easy to remove/evaporate and carcinogen.  DMF is a weak base.

It might be helpful

https://www.researchgate.net/publication/334118785_An_Overview_on_Common_Organic_Solvents_and_Their_Toxicity