While we are on the subject of eating seafood and subject of allergies
has come up, I have a question or two.

For years I ate every kind of seafood (with gusto!). Then, staring
about six years ago, I developed some allergies. I get a swelling
reaction from nori (the seaweed wrap around sushi) and soft-shelled
crab. Maki-sushi is a no go, but nigiri sushi seems okay (is it's a
kind of nigiri that comes with a little nori seat belt, I just don't
eat the obi). I'm guessing it is the iodine I am reacting to, but not
all seafood effects me. I can eat shrimp and lobster and have no
reaction. Perhaps, as one eats the entire soft-shelled crab, I am
reacting to the seaweed the crab has just eaten?

I know what you are thinking. This is a mollusk list and I'm talking
crustaceans. But at about the same time oysters start making me sick.
No swelling, no rash, but heaving-ho with great force and exhaustion
for about 24 hours after the fact. At first i thought it was a bad
oyster, but I had reactions on different occasions with the same
reaction. I've held off on most bivalves, except for the odd cup of
clam chowder, but I can eat conch, Strombus gigas, Strombus costatus,
with no problem. What am I reacting to? A specific protein in the
oyster?

I ask because last month I was in California and had a chance to try
abalone. I've always wanted to taste abalone, but I wasn't sure if it
would be a problem for me. Any thoughts folks?