A toxic algal bloom in several Tasmanian waterways prompts the Australian Health Department to issue warnings against eating shellfish such as clams, mussels, and oysters due to the risk of paralytic shellfish poisoning, with symptoms that include tingling and weakness of the arms and legs, and in extreme cases, death.
http://www.themercury.com.au/article/2011/03/26/217611_tasmania-news.html
http://www.media.tas.gov.au/release.php?id=31929