有没有有毒的海藻海带？

海水海藻海带都没有毒。好不好吃，可以不可以消化就是另外一回事。大多数的淡水海藻都有毒。 http://en.wikipedia.org/wiki/Edible_seaweed

但是，有两种海藻要回避，因为有害。一种是巨大鞘丝藻（lyngbya majuscula），另一种是鹿尾菜或羊栖菜（hijiki ）。

I often get asked if there are any poisonous seaweed around Britain. From my own research I discovered that Desmarestia is the only poisonous seaweed that you should leave well alone. However I wanted to double check my own knowledge against that of a world class expert.

So I went and asked Professor Michael Guiry, Director of AlgaeBase and world authority on seaweed. Here’s his reply:

“As far as I know, there are no really poisonous seaweed in this part of the world. “Our” Desmarestia species (4 of them and as you said mostly in deep water) produce sulphuric acid and can have a cellular pH of 2.

Anything else you might want to eat is free of poisons in the conventional sense as far as I am aware. However, care should be exercised when collecting in areas with high coliform counts and other bacteria, particularly in estuaries.

I have seen some really disgusting places on the south coast of England and would be loath to eat anything collected from shores from Portsmouth east to Norfolk, and anything from the major estuaries. The same applies to Dublin Bay, Cork Harbour, Inner Galway Bay, and Belfast Lough.”

So there you have it, straight from the horses mouth so-to-speak.

http://www.eatweeds.co.uk/are-there-any-poisonous-seaweeds-in-britain

Lyngbya majuscula is a benthic filamentous marine cyanobacterium, which in recent years appears to have been increasing in frequency and size of blooms in Moreton Bay, Queensland. It has a worldwide distribution throughout the tropics and subtropics in water to 30m. It has been found to contain a variety of chemicals that exert a range of biological effects, including skin, eye and respiratory irritation. The toxins lyngbyatoxin A and debromoaplysiatoxin appear to give the most widely witnessed biological effects in relation to humans, and experiments involving these two toxins show the formation of acute dermal lesions. Studies into the epidemiology of the dermatitic, respiratory and eye effects of the toxins of this organism are reviewed and show that Lyngbya induced dermatitis has occurred in a number of locations. The effects of aerosolised Lyngbya in relation to health outcomes were also reported. Differential effects of bathing behaviour after Lyngbya exposure were examined in relation to the severity of health outcomes. The potential for Lyngbya to exhibit differential toxicologies due to the presence of varying proportions of a range of toxins is also examined. This paper reviews the present state of knowledge on the effects of Lyngbya majuscula on human health, ecosystems and human populations during a toxic cyanobacterial bloom. The potential exists for toxins from Lyngbya majuscula affecting ecological health and in particular marine reptiles.


http://www.ncbi.nlm.nih.gov/pubmed/11757852



Seaweed is Contaminated


Seaweed does to the ocean what plants do to our air. They purify it. The downside is that the ocean is much more polluted than our air. Seaweed catches and filters a lot of pollution. Heavy metals, toxic material, and any type of junk that finds its way into our water also has a strong possibility of ending up in your food: in that seaweed that you eat.

The Food Standards Agency even advised people not to eat a type of seaweed called hijiki because of the high levels of arsenic that it contains. There are probably various types of toxins that could end up in the seaweed that you eat, simply because the ocean has never been so polluted and it keeps getting worse.

When seaweed is labeled as “organic,” it simply means that the seaweed has been tested to make sure the levels of heavy metals they contain is not above a certain level judged “problematic.” It doesn't mean that the seaweed doesn't contain any heavy metal. In fact, it would be impossible to make such a claim because seaweed sold is a wild food that comes from the same ocean that everybody knows to be polluted.


http://www.fredericpatenaude.com/articles/seaweed.html


Hijiki or hiziki (ヒジキ, 鹿尾菜 or 羊栖菜 hijiki^?) (Sargassum fusiforme, syn. Hizikia fusiformis) is a brown sea vegetable growing wild on rocky coastlines around Japan, Korea, and China. The written kanji forms of its two names, which are examples of ateji, literally mean deer-tail grass and sheep-nest grass, respectively.

Possible arsenic health risk

Several government food safety agencies advise consumers to avoid consumption of hijiki seaweed. Test results have indicated that levels of inorganic arsenic were significantly higher than in other types of seaweed. These results have been independently verified.^[1]
Government food safety agencies that have issued warnings include:

• the Canadian Food Inspection Agency (CFIA)^[2]
• the Food and Environmental Hygiene Department (FEHD) of Hong Kong^[3]
• the Food Standards Agency (FSA) of the United Kingdom^[4]
• the New Zealand Food Safety Authority (NZFSA)

The Ministry of Health, Labour and Welfare of Japan has responded with a report pointing out that, while the consumption of more than 4.7 g hijiki seaweed per day could result in an intake of inorganic arsenic that exceeds the tolerable daily intake for this substance, the average daily consumption for Japanese people is estimated at 0.9 g.^[5] Several of the reports from other food safety agencies acknowledged that occasional Hijiki consumption was unlikely to cause significant health risks, but advised against all consumption regardless.^[3][4]
Although no known illnesses have been associated with consuming hijiki seaweed to date, inorganic arsenic has been identified as carcinogenic to humans, and exposure to high levels of inorganic arsenic has been linked with gastrointestinal effects, anemia and liver damage. People who follow a macrobiotic diet that often includes large amounts of seaweed may be at greater risk.

http://en.wikipedia.org/wiki/Hijiki