No. Firstly let me clear up one thing, by carbon sequestration I assume that you are referring to CCS. Now, in brief CCS involves capturing carbon dioxide and pumping it into old oil and gas fields. It is pumped directly into the reservoir rock and therefore, assuming nothing goes wrong with the pipe, never comes into contact with the marine environment.
Obviously there are potential problems with pipe rupturing and other such events but in reality these are no different from issues already present in marine drilling programmes. All carbon storage is through, as I said previously, old oil and gas fields and maybe saline aquifers so the equipment will not disturb ecosystems further. As the gas never enters the ecosystem (in theory) then it won't have an effect.
The only major issue at this time is the lack of reliable equipment in place to monitor potential leakage.