Watching Our Water Ways

Environmental reporter Christopher Dunagan discusses the challenges of protecting Puget Sound and all things water-related.
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Water quality is defined by its effect on sea life

Friday, April 11th, 2014

We just completed another group of stories in the ongoing series we’re calling “Taking the Pulse of Puget Sound.” This latest story package is about marine water quality and marine sediments. (The stories themselves require a subscription.)

Noctiluca, a type of plankton that could disrupt the food web, has grown more prevalent in recent years. Photo by Christopher Krembs, Eyes Over Puget Sound

Noctiluca, a type of plankton that could disrupt the food web, has grown more prevalent in recent years.
Photo by Christopher Krembs, Eyes Over Puget Sound

For all my years of environmental reporting, I have to say that I’ve never really understood the meaning of water quality. Keeping the water free of chemicals and fecal bacteria is one thing. Safe levels of oxygen, temperature, acidity and suspended sediment are other important factors.

But in the real world, you never find ideal conditions. You take what you get: physical conditions dictated by weather, climate and bathymetry; a strange brew of toxic chemicals; and a mix of nutrients and organic material, all drifting through complex cycles of life and death.

Water quality means nothing without the context of living things. More than 1,000 species of tiny organisms live in or on the mud at the bottom of Puget Sound. In many areas, sensitive species have disappeared. We are left with those that can tolerate harsher conditions. Why are they dying off? What can be done about it?

Some plankton species are becoming more dominant, and the effects on the food web are unknown. When water quality is poor, Jellyfish are displacing forage fish, disrupting the food supply for larger fish.

We know that toxic chemicals are spilling into Puget Sound in stormwater and getting into the food web, first touching the tiniest organisms and eventually causing havoc for fish, marine mammals and humans. Compounds that mimic hormones are affecting growth, reproduction and survival for a myriad of species. Because of biomagnification, some chemicals are having serious effects at concentrations that could not be measured until recently.

Puget Sound can’t cleanse itself by flushing its chemicals and waste out to sea, as most bays do. Puget Sound is long and narrow and deep, and the exchange of water takes a long time. Most of the bad stuff floating in the water just sloshes back and forth with the daily tides.

We can’t forget that some of the good stuff floating around are microscopic plants that feed the food web, along with a variety of larvae that will grow into fish, shellfish and many other creatures. But many of these planktonic life forms are vulnerable to chemicals, which can reduce their ability to survive against predators, tipping the balance in unknown ways.

Understanding water quality is not so much about measuring what is in the water as understanding the effects on living things. Which species are missing from a given area of Puget Sound, and what killed them off?

Biological monitoring has been around for a long time, but we may be entering a new phase of exploration in which we begin to connect the dots between what takes place on the land, how chemicals and nutrients get into the water, and what that means for every creature struggling to survive.

We have some brilliant people working on this problem in the Puget Sound region. I would like to thank everyone who has helped me gain a better understanding of these issues, as I attempt to explain these complexities in my stories.

—–

While I was looking into the sediment story, Maggie Dutch of Ecology’s sediment monitoring team introduced me to a huge number of benthic invertebrates. In a blog she calls “Eyes Under Puget Sound,” she talks about the monitoring program and offers a slideshow of some of the bottom creatures. See also Ecology’s Flickr page.

For some amazing shots of polychaete worms, check out the work of marine biologist and photographer Alex Semenov who took these colorful pix in Russia and Australia.


Amusing Monday: Celebrating World Water Day

Saturday, March 22nd, 2014

I’m posting this “Amusing Monday” entry two days early, because today is officially World Water Day, as declared by the United Nations.

Photo by xxxx. Copyright World Water Day, used with permission

Photo by Murli Menon.
Copyright World Water Day, used with permission

I guess the timing is not that important. After all, I don’t expect anyone to go out and march in a World Water Day parade, or fire off water pistols in celebration, or even drink water in excess and then sleep in the next morning. But if you are inclined to celebrate, you may as well celebrate the essential value of water.

The photos on this page are the top choices of Facebook voters in a contest sponsored by World Water Day.

The picture of the white tiger, called “Water Preserves the Earth,” is said to demonstrate that all creatures need water, yet the tiger realizes that this water is polluted and hesitates to drink it.

Photo by Joseph Galea Copyright World Water Day, used with permission

Photo by Joseph Galea
Copyright World Water Day, used with permission

The second photo, called “Water Gives Energy,” illustrates the hope of a future when all children have access to a safe supply of water.

A slide show of the best photos submitted in the context can be found on the World Water Day Flickr page.

Finally, the two videos below provide a strong contrast between technologies available to produce a clean supply of water for everyone.


Any ideas for a no-discharge zone in Puget Sound?

Tuesday, February 25th, 2014

Washington Department of Ecology is pushing ahead with its plan to create a “no-discharge zone” for Puget Sound, which would prohibit the discharge of sewage from boats, even those with a Type II marine sanitation device. Check out my story last week in the Kitsap Sun, Feb. 19 (subscription).

Proposed no-discharge zone for Puget Sound // Washington Department of Ecology

Proposed no-discharge zone for Puget Sound
Washington Department of Ecology

For many people, it is disconcerting to think about mobile toilets traveling everywhere in Puget Sound and discharging their waste anywhere and at any time.

Kitsap Public Health District has gained a reputation for tracking down sources of pollution and getting them cleaned up. If you have a failing septic system, for example, you are expected to get it fixed. Many of the Dyes Inlet beaches between Bremerton and Silverdale were reopened to commercial shellfish harvesting, thanks in no small part to these persistent efforts to clean up bacterial pollution.

Sewage-treatment plants still discharge some bacteria, despite advanced treatment processes. Consequently, shellfish beds are permanently closed around treatment plant outfalls, with the closure zone dependent on the level of sewage treatment. And when there are sewage spills, long stretches of beach may be closed to shellfish harvesting for 10 days or longer.

When they are working properly, Type II marine sanitation devices aboard boats are fairly good at killing bacteria, although levels are still above state water-quality standards. Less certain is what happens to human viruses, including hepatitis, that may not be killed. In addition, marine toilets release chemicals — such as chlorine, quaternary ammonia and formaldehyde — into the water.

To delve further, check out:

It’s not hard to see why the goal would be to eliminate discharges of boater waste into Puget Sound, assuming that sufficient pumpout stations exist for people to offload their waste. Pumpout stations are connected to sewage-treatment systems, which do a better job of disinfection and remove most solids that can contribute to algae blooms and low-oxygen conditions.

Creating a no-discharge zone is one goal of the Puget Sound Action Agenda (PDF 16.4 mb) developed by the Puget Sound Partnership.

Ecology Director Maia Bellon seemed to strike the right tone when she announced the petition for a no-discharge zone (PDF 8.1 mb) in Puget Sound:

“We want to reach out and invite comments, questions and suggestions over this draft proposal. We’re working with boating, shipping and fishing leaders, and now is the time for broader perspective and feedback. Everyone who lives here has a vested interest in a healthy Puget Sound.”

Her approach leaves the door open to some creative solutions for getting everyone in compliance with the no-discharge zone. As I showed in last week’s story, the no-discharge zone could be a hardship for some tugboat and fishing boat operators. One estimate for converting a tugboat is $125,000.

Ecology’s solution so far has been simple: Give those without holding tanks three years to install the tanks and plug up theirs discharge pipes.

Other solutions may be possible, although they could create administrative burdens for Ecology. What about the idea of creating an exemption for boats that have no holding tanks? Boat owners could pay an annual fee for the exemption, and the money could go into a fund to assist owners with the cost of conversion. Maybe a conversion should be required, if necessary, at the time a boat is sold. It’s just an idea.

When applying for an exemption from the no-discharge zone, boat owners should agree to discharge treated wastes at a safe distance from the beach. Maybe they should be required to know where certified shellfish beds are located and stay even farther away.

I realize these ideas would complicate a simple plan, and maybe there are better ideas. In general, I believe that a reasonable solution should be proportional to the problem. We should not kill a rat with heavy explosives, while ignoring the cost of repairs.

To see how more than 20 other states are addressing no-discharge zones, visit the Environmental Protection Agency’s website on vessel sewage discharges and a state-by-state breakdown of no-discharge zones.

When I broke this story in September, I interviewed others who had thoughts on the issue. See Kitsap Sun, Sept. 25 (subscription).

For recreational boaters, check out “Beating the Pumpout Station Blues” by Capt. Mike Brough of the Coast Guard.


Student project could lead to official state oyster

Friday, February 14th, 2014

Nobody was really talking about designating an official “Washington state oyster” until 14-year-old Claire Thompson came along. Now the state Senate has approved a bill, on a 47-1 vote, to list the Olympia oyster as the state’s official oyster.

Claire is an eighth grader at Olympia’s Nova School, which requires a yearlong project involving something that students care deeply about and can make a difference. Claire, who hopes to become a marine biologist or oceanographer, developed a sense of history for the once-prominent Olympia oyster, as we learned from her testimony before the Senate Governmental Operations Committee.

The full testimony on SB 6145 falls between 40:00 and 51:00 in the video on this page.

“Pollution near historic beds caused many closures of the fishery and rallied the oyster farmers to fight for the earliest pollution control regulations for clean water and cleanup,” Claire told the committee.

Ostrea lurida, the scientific name for the Olympia oyster, is the only native oyster to the region. The Pacific oyster, imported from Japan in the 1920s, makes up most of the production today, but the tiny Olympia is making a comeback as a unique delicacy with natural ties to the region.

Claire talked about ocean acidification, caused by excess carbon dioxide in the atmosphere, and its ongoing threat to the ecological health of Puget Sound, Hood Canal and other bays and estuaries.

“Ostrea lurida,” she said, “stands as a living symbol of Washington’s history, from the earliest Native Americans through the pioneers down through statehood to the present day, deserving protection as our native oyster. Please join me in fighting to protect not only our native oyster but our waters as well.”

Claire is the daughter of Rowland Thompson, lobbyist for Allied Daily Newspapers of Washington, who encouraged her to develop her project and speak before the Legislature.

Jim Jesernig of Pacific Coast Shellfish Growers Association said he supports the bill, even though it came as a surprise to his group.

“We have been very pleased working with Claire,” Jesernig said. “It’s very interesting. From the industry, we did not see this. We were working on derelict vessels and a whole bunch of things going on. Claire has worked with folks in Willapa Harbor and the South Sound. We would like to support this in any way.”

If next approved by the house, the Olympia oyster will become the official state oyster, joining:

  • The orca, the official marine mammal;
  • The Olympic marmot, the official endemic mammal;
  • The willow goldfinch, the official bird;
  • The steelhead trout, the official fish; and
  • The common green darner dragonfly, the official insect.

By the way, Puget Sound Restoration Fund, a nonprofit group, has been working for years to restore the Olympia oyster to Puget Sound. I first wrote about this issue in 1999 in a piece called “Native oyster making a comeback — with help.” A companion piece about the taste of the little oyster was titled “Olympia Oyster Gains Respect.” I also presented the tribal perspective in “Tribal Officials Welcome Oyster Restoration.”

Since then, Puget Sound Restoration Fund has helped rebuild native oyster populations in many bays, with one of the greatest successes in Liberty Bay near Poulsbo. Betsy Peabody, executive director, told me this morning that her group has great hopes for success in Dyes Inlet near Silverdale and in Port Gamble Bay in North Kitsap. A new oyster hatchery in Manchester is expected to be in operation later this year.

Washington Department of Fish and Wildlife has developed a long-term restoration plan for the Olympia oyster with 19 areas listed for habitat restoration:

Drayton Harbor
Bellingham Bay (South) Shoreline, Portage Island, and Chuckanut Bay
Samish Bay
Padilla Bay
Fidalgo Bay
Similk Bay
Sequim Bay
Discovery Bay
Kilisut Harbor
Port Gamble Bay
Quilcene Bay
Union River/Big and Little Mission Creek(s) deltas
Liberty Bay and sub-inlets
Dyes Inlet and sub-inlets
Sinclair Inlet
Point Jefferson-Orchard Point complex of passages and inlets
Budd Inlet
Henderson Inlet
Harstine/Squaxin Islands complex of passages and inlets


Kitsap County acquires prime forest, shoreline

Wednesday, February 12th, 2014

It’s official. Kitsap County has become the proud owner of 535 acres of prime lowland forest, including 1.5 miles of shoreline on Port Gamble Bay. See the story I prepared for tomorrow’s Kitsap Sun (subscription).

Port Gamble Bay shoreline // Photo by Don Willott

Port Gamble Bay shoreline // Photo by Don Willott

This is prime property, both from an ecological and recreational viewpoint. It is extremely rare to find a place where so much shoreline belongs to the public, especially in a populated area like Kitsap County. With restoration work and time for nature to respond, this property could return to a near-pristine condition.

This is the first property sale completed by the Kitsap Forest & Bay Project. More than two years ago, I attended a kick-off meeting to launch the fund-raising effort. It all began with an option agreement to buy up to 7,000 acres of forestland from Pope Resources. See Kitsap Sun, Oct. 19, 2012.

The effort followed a disbanded plan by the county to trade the land for increased housing density near Port Gamble. (See Kitsap Sun, Jan. 19, 2010.)

The new effort was spearheaded by Cascade Land Conservancy, now called Forterra. CLC President Gene Duvernoy spelled out the task ahead as he announced that Michelle Connor, a vice president of CLC, would be put in charge. Duvernoy declared:

“This is probably the most important project we can accomplish to save Puget Sound… Anytime we have a real thorny project, we hand it to Michelle to make it happen… This option agreement is a reason to celebrate, but now we need to get serious. Now, we can look at all the financing and funding possibilities. Until today, we were unable to do that.”

Other acquisitions are expected to be completed soon, but it remains unclear how much of the 7,000 acres can be acquired from Pope.

In celebration of the completed sale, I would like to share the statements made in a news release by a variety of people involved in the project:

Kitsap County Commissioner Rob Gelder:

“This acquisition has been years in the making and the beginning of a series of great things to come in 2014. We are lining up funding to protect additional lands from Kingston to Port Gamble as part of this preservation effort.”

Michelle Connor, Forterra’s executive vice president:

“Conservation of these lands will help sustain the cultural heritage and health of our communities, the functioning of our environment and diversity of our economy. Moving the whole effort forward is a testament to the leadership of local residents, Kitsap County, the Port Gamble S’Klallam Tribe, the Suquamish Tribe, and the state of Washington.”

Suquamish Tribal Chairman Leonard Forsman:

“The public purchase of the shoreline block at Port Gamble Bay is an accomplishment worth celebrating. The Suquamish Tribe is grateful that this critical marine habitat will be protected for time immemorial and help in efforts to protect the water quality of Port Gamble Bay.”

Jeromy Sullivan, chairman of the Port Gamble S’Klallam Tribe:

“One of my tribe’s ongoing priorities is to ensure that Port Gamble Bay remains productive and healthy for future generations. The conservation of this property furthers that goal by protecting water quality, preventing development and limiting stormwater runoff and other associated impacts.”

Jon Rose, president of Olympic Property Group, Pope Resources’ real estate subsidiary:

“We are proud to be working with the community to protect these forests, beaches and trails for future generations. This purchase is a prize that has been earned through nearly a decade of dedicated efforts by the local community.”

Sandra Staples-Bortner, executive director of Great Peninsula Conservancy, a key player in the acquisition:

“The many community partners involved in the Kitsap Forest & Bay Coalition have dedicated countless hours to help achieve this historic land purchase, handing out trail maps, speaking to community groups and marching in parades. And when it came down to the wire, the coalition raised over $10,000 in three days to fill the final funding gap.”

Maia Bellon, director of the Washington Department of Ecology:

“Restoring and sustaining the ecological systems that support Port Gamble Bay is critical for Hood Canal, Puget Sound, and all of us who call Washington home.”


Geoduck market expands to Chinese neighbors

Sunday, February 9th, 2014

The market for geoducks harvested in Washington state has shifted from China to other Asian countries, primarily Hong Kong and Vietnam, according to certificates issued by the Washington State Department of Health.

Kitsap Sun photo

Kitsap Sun photo

We learned a week ago that the Chinese ban on imports from the U.S. West Coast will continue until Chinese health authorities better understand the U.S. system of protecting public health. See Water Ways, Feb. 4, with links to other sources of information.

The ban caused exporters to find new markets. I reported these numbers in a story published in yesterday’s Kitsap Sun (subscription):

“Health certificates issued by the Washington State Department of Health totaled 757 in January — more than double the 373 certificates issued in January 2013, when shipments were still going into China. These certificates are required to identify the shellfish-growing area and ensure that a given shipment of seafood is safe to eat.

“Of the 757 certificates issued in January, 409 designated shipments into Hong Kong, while 243 designated shipments into Vietnam. Other shipments were to Malaysia, 38; Thailand, 24; Indonesia, 8; and a number of countries with smaller shipments. Because shipments were closed off to China in January, no certificates were issued for that country.”

Wild geoduck harvesting is a multi-million industry, bringing significant revenues to businesses, tribes and state government.

Yesterday’s story, which was picked up by the Associated Press, describes how state and tribal geoduck divers appear to be on track to take their allocations of deep-water geoducks.

How many of these giant clams are getting into China illicitly and by what routes has been hard to track down. I have collected many rumors and comments on background, but I’ve been unable to verify the most provocative stories.

A new harvest year begins in April with new allocations of geoducks for the state and tribes. Meanwhile, the Department of Natural Resources has scheduled a bid opening for state geoduck tracts later this month.

It will be interesting to see how the Chinese ban on imports from the U.S. West Coast affects the price of geoducks over the coming year. So far, after a short closure when the ban was imposed, prices for wild geoducks have been holding fairly stable, according to officials involved in the market.


China maintains ban on shellfish imports

Tuesday, February 4th, 2014

Business and government officials involved in the lucrative geoduck export market got some bad news on Friday, when federal authorities released a letter they had received from the Chinese government.

Kitsap Sun photo

Kitsap Sun photo

The letter raises many questions — at least from a Chinese perspective — about how the U.S. regulatory system protects public health. The message from Chinese health authorities dashes the hopes of industry officials for a quick lifting of the Chinese ban on shellfish imports from the U.S. West Coast.

I wrote about this issue for Saturday’s Kitsap Sun (subscription). My story was picked up by the Associated Press and distributed widely. (If you don’t subscribe to the Sun, see The Columbian, Vancouver, for the AP version.)

Washington state has a proud reputation for protecting public health when it comes to shellfish, and the letter from China does little to dispel suspicions among those who think that China may have ulterior motives. After all, Chinese authorities have done nothing to limit the geographic scope of the import ban or even limit the ban to geoducks only.

A statement (PDF 114 kb) from the National Oceanic and Atmospheric Administration concludes that the letter contains about 20 separate requests for information about testing and safety.

You may wish to read the the letter from China’s General Administration of Quality Supervision, Inspection and Quarantine (PDF 150 kb). As translated, the letter includes this statement:

“We don’t not have a full understanding of the US regulatory system including the definition of sea region and management, the official monitoring on PSP and heavy metals and the responsibility among the relevant government agencies, and we have not conducted an on-site evaluation neither.”

The letter says the suspension of imports may be reduced to a specific area after certain questions are answered. It calls on the U.S. to develop an action plan for evaluation and outlines a review process, including a visit by an “expert team” from China to evaluate the geoduck inspection programs.

Officials at all levels in the U.S. say they are evaluating the questions posed in the letter and preparing a coordinated response.

Previous entries in Water Ways:

Jan. 9, 2014: Geoducks test OK, but what’s behind Chinese ban?

Dec. 24, 2013: Health officials to quickly test geoducks for arsenic


Chinese TV discusses shellfish import ban

Thursday, January 23rd, 2014

U.S. officials say they have not heard a word from Chinese health authorities since the Washington State Department of Health sent test results showing that geoducks from Puget Sound are safe to eat.

A ban on shellfish imports from the Northwest continues. By all accounts, it appears that U.S. shellfish exporters will miss a chance to provide geoducks, oysters and other shellfish to China during lucrative Chinese New Year celebrations next week.

The National Oceanic and Atmospheric Administration has sent the health department’s test results to China, NOAA spokeswoman Connie Barclay told me yesterday. “We will continue to work with folks to see if we can resolve this issue,” she said.

Meanwhile, Chinese Central Television (CCTV), a government-sponsored TV network in China, has produced a video describing the issue, including the economic effects on shellfish growers. It’s a pretty straightforward piece, but offers no hint about what further steps may be taken by the Chinese government.

For background, see my last entry in Water Ways on Jan. 9. which includes links to other sources. The same goes for an entry on Dec. 24 and the first one on Dec. 17.

The bottom line is that nothing has happened for weeks. Shellfish growers are waiting patiently, hoping this does issue does not grow into an extended trade dispute.


Geoducks test OK, but what’s behind Chinese ban?

Thursday, January 9th, 2014

Now it is up to Chinese officials to decide upon shellfish imports to their country, as uncomfortable as that may be for U.S exporters. I’ve begun to learn about international trade policies to better understand the confusing actions of Chinese health authorities.

As you’ve probably heard by now, officials with the Washington State Department of Health have concluded from a new round of testing that arsenic in geoducks from Poverty Bay presents no legitimate health concern. That seems to contradict findings from Chinese health authorities, who cited high levels of arsenic in Poverty Bay geoducks when they suspended shellfish imports from the U.S. West Coast.

Unfortunately, the Chinese have failed to reveal how they came to their findings, and they discarded all the geoducks used in their tests. Divers from the Washington Department of Natural Resources collected new geoducks from Poverty Bay, and state health experts conducted new tests. The findings were released Tuesday, and I covered that in some detail in a story published in yesterday’s Kitsap Sun (subscription). Also, check out Water Ways, Dec. 24, to understand the different types of arsenic.

USTR report

Results from the Washington state health lab showed that arsenic levels in all parts of the geoduck came in under the Chinese limit of 0.5 parts per million, except for the skin. Dave McBride, a toxicologist for the state health department, told me that cooks in both China and the U.S. blanch the geoduck to remove the inedible skin, so that’s not a factor.

But even if one consumes the whole geoduck, tests on the “whole body” found only one composite sample out of 12 that exceeded the Chinese standard. Of course, it would have been more convincing if none of the whole-body samples came in above 0.5 ppm.

A private lab also tested geoducks from Poverty Bay, and those results came in even lower. The differing findings probably resulted from the different methods used, Dave McBride told me. It might be wise to try to reconcile the differences and report the scientific uncertainty (possible range) represented by the two techniques.

Meanwhile, I’ve begun talking to experts on Chinese trade, who say it is not unusual for governments around the world to use alleged health concerns to gain a trade advantage.

As I reported in yesterday’s story, the U.S. Trade Representative, a presidential cabinet post, reported to Congress at the end of last year about what appeared to be unjustified health concerns blocking a variety of agricultural imports into China:

“In 2013, serious problems have remained for U.S. exporters, who are faced with nontransparent application of sanitary and phytosanitary measures, many of which have appeared to lack scientific bases and have impeded market access for many U.S. agricultural products.

“China’s seemingly unnecessary and arbitrary inspection-related import requirements also continued to impose burdens and regulatory uncertainty on U.S. agricultural producers exporting to China in 2013 … Products most affected in 2013 included poultry, pork and beef.”

Dongsheng Zang, a University of Washington law professor who specializes in Chinese trade, and Debra Glassman, faculty director of the UW’s Global Business Center, helped me understand the trade situation for yesterday’s story. Here are some of the key points I came away with:

  • Chinese officials don’t always base their decisions on the best evidence,, even though agreements under the World Trade Organization require them to do so. In 2011, China stopped imports of oysters from Washington state following reports of a few people getting sick from eating raw oysters from Hood Canal. Zang says Chinese officials based their actions only on “media reports.”
  • Import bans often come quickly and take a long time to resolve. That happens not just in China but in other countries and the European Union, especially when the dispute must be resolved by the World Trade Organization.
  • International agreements require that any import restrictions must be the “least-trade-restrictive” to protect the public, such as banning shellfish from specific bays where problems are identified, Glassman said.
  • The Chinese ban on U.S shellfish could be designed for a domestic audience inside China. “I can only speculate,” Zang said. “Food safety is a huge issue in China. It’s really hard to say whether this (geoduck ban) is about public health or domestic policy.”

An official in the office of the U.S. Trade Representative in Washington, D.C., told me (on background) that the office is watching this issue closely. If the shellfish ban develops into a full-fledged trade dispute, that office will become involved.

I realize that geoduck harvesters and government officials don’t want to accuse the Chinese of acting inappropriately. They just hope that the ban will be lifted without a drawn-out dispute. Meanwhile, those in the industry are losing millions of dollars by being shut off from their most important market for the giant clams.


Health officials to quickly test geoducks for arsenic

Tuesday, December 24th, 2013

Shellfish and toxicology experts with the Washington State Department of Health are rushing to test new samples of geoducks from Poverty Bay near Federal Way. Poverty Bay is the apparent source of the geoducks that triggered a Chinese ban on the imports of all bivalves from the U.S. West Coast.

Photo: Washington Sea Grant

Photo: Washington Sea Grant

Since I wrote about this issue in Water Ways last Tuesday, state health officials have learned that arsenic — not paralytic shellfish poison — was cited by Chinese health officials as the cause of their concern in the Poverty Bay geoducks.

Past studies by state researchers have concluded that arsenic is not a health concern in shellfish taken from Puget Sound, based on sampling from some of the most polluted bays in the region. A letter (PDF 118 kb) sent last week from the U.S. Seafood Inspection Program to China’s health officials calls for China to lift its unusual ban. The letter cites a 2007 health assessment on arsenic in geoducks from Poverty Bay, where the giant clams were deemed safe to eat.

As a precaution, Washington Department of Natural Resources has closed the 135-acre Redondo Tract in Poverty Bay to shellfish harvesting until the Chinese ban can be resolved, according to a statement issued Friday from Public Lands Commissioner Peter Goldmark.

One of the complicating factors in dealing with arsenic in shellfish is that the organic forms (primarily arsenobetaine) are not toxic, yet they are far more prevalent than the toxic inorganic forms (arsenic III and arsenic V ).

It is far easier to measure total arsenic than to separate organic from inorganic forms, so researchers often make assumptions. To be extra safe, they have assumed for years that toxic inorganic arsenic is less than 10 percent of total arsenic. Now, they have begun to rely on more recent geoduck studies from Seattle’s Richmond Beach (PDF 327 kb) that showed the inorganic form of arsenic to be less than 1 percent of total arsenic.

Dave McBride, a toxicologist with Washington’s Department of Health, told me the Chinese were reporting levels of arsenic at 1.7 parts per million, but they failed to say whether that was total arsenic or inorganic arsenic. The Chinese health limit was reported as 0.5 parts per million inorganic arsenic.

It also makes a difference whether the whole geoduck was tested or just the edible parts. The skin, which is generally discarded when cooking, appears to concentrate more arsenic than other parts, but the levels still are not high enough to be a concern.

A 2002 study of shellfish from several polluted water bodies in Puget Sound (PDF 1.5 mb) found levels of inorganic arsenic in clams to fall in a range from 0.015 to 0.035 parts per million. A 2007 health assessment of geoducks from Poverty Bay (PDF 874 kb) found total arsenic levels ranging from 2.28 of 4.96 parts per million.

Assuming inorganic arsenic at 1 percent of total arsenic the maximum value is .05 parts per million for shellfish from Poverty Bay. That’s one-tenth the level of concern reported by the Chinese.

Initially, Poverty Bay was an issue because of two sewage outfalls in the area and the proximity to Tacoma’s former ASARCO smelter — even though most airborne pollution landing on the water gets well dispersed. But the formal health assessment allayed concerns about arsenic and other metals as well.

Arsenic always raises initial concerns, because its inorganic form is known to disrupt the metabolism of multi-celled organisms, including humans. Also, it has been known to cause cancer. Because inorganic arsenic levels in shellfish are normally low, no federal or state standards have been established.

In response to the Chinese ban, the Department of Natural Resources went out yesterday and collected new geoduck samples from Poverty Bay. The idea will be to present findings on both total arsenic and inorganic arsenic, thanks to more sophisticated analytical equipment at the Department of Health laboratory.

Three geoducks will be put together to create a composite sample. In all, two composite samples each will be associated with 12 different locations in the bay, according to McBride.

Edible geoduck tissue will be separated from the “gutball,” which may be prepared by some Chinese cooks, I’m told. If enough samples are available, the whole geoduck (minus the shell) may be tested as well, or possibly just the skin.

One long day of processing is planned for Thursday, and the samples will be run through analytical equipment over the weekend, McBride told me. A report on the findings can be expected next week.

For information about the China ban on shellfish, check out a fact sheet from the state’s Office of Shellfish and Water Protection (PDF 282 kb).


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"In the end, we will conserve only what we love, we will love only what we understand, and we will understand only what we are taught."Baba Dioum, Senegalese conservationist

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