An MP has vowed to challenge a company after concerns "toxic sludge" being dumped near the shoreline is harming sea life.

There are fears that dredged sediment disposed of by Brighton Marina in the Beachy Head West Marine Conservation Zone between the marina and Ovingdean is smothering marine animals.

Sussex Wildlife Trust, residents and independent councillor for Rottingdean and West Saltdean Bridget Fishleigh want the marina, which currently dumps the sediment about 50m from the shoreline, to dispose of it further out to sea.

They are concerned that marine life, including blue mussel beds, native oysters and short-snouted seahorses, is being “smothered” by the sludge.

They have also said the impact on humans swimming in the area is “unknown”.

Cllr Fishleigh said she often sees black debris washed up on the beach and brown sludge in rock pools.

One resident described the sediment as "toxic, "thick sludge".

Fears surfaced after Premier Marinas (Brighton) applied to renew its dredging licence.

The company has held the licence for ten years and the renewal ahead of its expiration in May 2025 would allow it to have a further ten.

The original licence was granted before the area was made a conservation zone.

Brighton Marina needs to dredge the entrance to the harbour to ensure boats can keep moving.

Sarah Ward, marine conservation officer at Sussex Wildlife Trust, said the activity should not continue.

“The licence was originally granted before the MCZ was designated but now that the area is protected, it’s not appropriate to allow this potentially harmful activity to continue,” she said.

“Sussex Wildlife Trust disagrees on principle that such an activity should be allowed to take place in a protected area and we’re also concerned over the precedent this may set for similar cases elsewhere.”

Chris Ward, MP for Brighton Kemptown and Peacehaven, has now taken up the cause.

"Protecting the natural environment is one of my main priorities,” he said.

“It’s vital that local residents’ voices are heard on this and I will be pressing the dredging company to provide a detailed explanation of their measures to protect the marine environment and wildlife."

A public consultation is under way and people have been encouraged to register their views.

Premier Marinas Brighton did not respond to requests for comment.