Mercury can be transported through the atmosphere and deposited into the sea via wet and dry deposition. Wet deposition occurs when mercury is dissolved in rainwater or snow and falls to the ground. Dry deposition occurs when mercury particles are deposited onto the ground without being dissolved in water.

Riverine inputs

Mercury can also enter the sea from rivers and streams. Mercury can be washed into rivers and streams from the atmosphere, from mining and industrial activities, and from natural sources such as volcanoes and geothermal vents.

Coastal erosion

Mercury can also enter the sea from coastal erosion. When coastal areas erode, mercury-containing sediments can be released into the water.

Dredging

Dredging can also release mercury into the sea. Dredging is the process of removing sediment from the bottom of a body of water. When sediment is dredged, it can release mercury that is bound to the sediment.

Shipping

Shipping activities can also release mercury into the sea. Mercury can be released from ships' engines, from the burning of fuel, and from the use of anti-fouling paints.

Ocean currents

Once mercury is in the sea, it can be transported by ocean currents. Ocean currents can transport mercury over long distances, and it can eventually be deposited in sediments or taken up by marine organisms.