team from Universiti Malaya Trengganu did a survey
of coastal and estuarine water
on the Malacca Strait coastline from Johor to Penang in March 2019.
The researchers found high concentrations of heavy metals (Arsenic, Cadmium, Lead, and Mercury) in waters off Johor, Port Klang (in the state of Selangor), and Penang.
The researchers have warned locals, through local mass media, to reduce their consumption
of local shellfish (see link below).
Conch, cockles, mussels, and whelks are farmed in several places along the coast of the Malacca Strait - and subsequently retailed in wet markets and sold, after preparation and cooking
, at food
stalls and in food
courts. Quite a few fin fish
are raised and farmed in cages off the coasts of Johor and Penang and also ultimately sold in wet markets and at food stalls, food courts, and restaurants.