No, it's not true. It's an urban legend that has been going around theinternet and is not based in fact. Here's a site that talks about thehistory of this fake email:
* [2 k6 Z. u1 [# q1 d/ g9 P3 o8 t2 N# }5 }tvb now,tvbnow,bttvbhttp://www.snopes.com/toxins/shrimp.htm |