[rashmi]

Is there any reason why BOD results would be higher than TOC results?

[Pradeep]

It is better to understand the meanings of these terms.

TOC is total mg of availbale organic carbon may be in one liter or one kilogram.

BOD is amount of dissloved oxygen (mg) concentration need to oxidize those organic compound in a one liter of solution by biological agents ( microorganisms).  This depend on the oxidation state of carbon also.

So two different parameters. That can happen.