Is deciduous forest chipping safe?

[Chun]

I know that Pine and Cedar is dangerous for hamsters as a substrate, But is deciduous forest chippings safe or not?

[SKB_Hamsters]

Deciduous as in hardwood shaving (like aspen) are safe for hamsters. Although I would check that the wood itself is safe before using to be on the safe side.
As you mentioned cedar and pine are usnasfe - although kiln-dried and dust extracted pine is okay to use.

I don’t know where you are located but if you are looking into natural based substrate then hemp bedding is another option or a paper based bedding (like Fitch in the UK)