The greatest microbial risks are associated with the ingestion of water contaminated with human and animal excrement. However, chemical contamination on ships could also occur as a result of transporting contaminated bulk water onboard to port, onboard cross-links or improper onboard handling.
Care should be taken when treating, transferring, producing, storing or distributing water in ships as shore-to-ship transfer is also a potential source of microbial or chemical contamination.
In addition to the transfer of water from land to ship and the storage of large quantities aboard the ship, many ships use desalination to produce their own drinking water, which is potentially contaminated.