Two lanes of the M20 between Hythe and Ashford were closed during this morning's rush hour when a lorry overturned.
The vehicle was carrying a liquid used to remove graffiti, which can be an irritant.
There was no leak but two London-bound lanes were closed as a precaution while firefighters dealt with the vehicle. Kent Highway Services also attended.
The incident happened at 6.30am near junction 11 and the Stop 24 service station.
The road was clear by 8.30am.
Firefighters from Folkestone and Canterbury attended plus a chemical specialist.