Organic Sea Vegetables?

Theresa Proud of Wilmington DE writes:

Thank you so much for the article, "Sea Vegetables: Don't Call 'Em Weeds." I am excited about the health benefits of sea vegetables, especially wakame, hijiki, and kombu, and have enjoyed experimenting with them in new recipes. I am concerned, however, about whether pollution and irresponsible harvesting must be considered. Could sea vegetables be affected by the same contaminants that poison the fish supply? Are "organic" sea vegetables available? Thanks for your great work.

Sincerely,

Theresa Proud

The Green Guide Responds:

A great number of environmental factors can affect sea vegetables and their organic status, many of which might not occur to the landlocked. For starters, pollutants can be discharged from nearby sewage treatment plants, chemical and industrial plants, and nuclear power facilities. Then there is the boat traffic (including boats used to harvest the sea vegetables) which can yield oil and gas slicks from leaky motors. Other contaminants arise from runoff, such as the fertilizers, pesticides or other pollutants that wind up in waterways from adjacent fields and hard-surfaced streets. One harvester, Larch Hanson, warns of pesticides on netting used to dry seaweed after its been collected.

The difference, however, between contaminants in the fish supply and those in sea vegetables, arises from metabolic processing. Certain Persistent Organic Pollutants (POPs), such as carcinogenic dioxins, collect in the body fat of fish and accumulate over time. Because of this, the highest concentrations are found in older, carnivorous fish, like swordfish or tuna, who have consumed numbers of contaminated fish over their lifespans. Since this isn't the case with sea vegetables, you won't find the same elevated concentrations of contaminants in them. Nonetheless, just as with non-organic land vegetables, pesticides residues can wind up on sea vegetables, not to mention residues from oil, gas, and the other substances.

So what protection do organic sea vegetables offer? According to the USDA-approved standards of a major certifier, OCIA, seaweed harvesting waters and sediment must be free of "significant contamination from residential, municipal, commercial, or industrial waste, emissions, tailings or affluent [sic]." They cannot be within twenty miles of a nuclear facility or three miles of an industrial or sewage discharge. Water testing, however, is not required. While these standards add confidence, they cannot ensure contaminants never reach the crop.

Since you're looking for the healthiest sea vegetables out there, it couldn't hurt to talk to the harvesters who provide your organic seaweed. Ask whether they harvest in motor boats or rowboats, whether their beds are near any towns or industry, and if they test their water regularly. If they are unhelpful, you can always find someone else who needs your business.