It's citrus...drink it for breakfast with your waffles. Problem solved.
Or read the MSDS on Park's website:
http://www.parktool.com/documents/9ee787ce0d64ad72466d7d837e0b56bbebc27cd4.pdf
13. Disposal Considerations
Dispose of spilled material in accordance with state and local regulations for waste that is non-hazardous by
Federal definition. Note that this information applies to the material as manufactured; processing, use, or
contamination may make this information inappropriate, inaccurate, or incomplete.
Note: that this handling and disposal information may also apply to empty containers, liners and rinsate.
State or local regulations or restrictions are complex and may differ from federal regulations. This
information is intended as an aid to proper handling and disposal; the final responsibility for handling and
disposal is with the owner of the waste. See Section 9 - Physical and Chemical Properties.
It's non-hazardous, but what it stripped off your chain might be a hazard. Or at least useful to spray where you don't what grass and weeds to grow. If they do grow where you spray, check to see there are not more than three eyeballs per plant. More than three indicates a species invading from another planet.