View west from Almaden Quicksilver County Park toward Loma Prieta, highest peak of the Sierra Azul. All photos by Andrew Alden.

In the foothills due south of San Jose sit the remnants of California's first mining bonanza, the New Almaden mercury district. Today Almaden Quicksilver County Park is a rugged playground for hikers, bicyclists and equestrians, but lovers of geology and mines have a special kind of fun there.

The first Californians mined a deep-red ore they called mohetka in the heights of Los Capitancillos Ridge. Like other ancient peoples around the world, they used it as a pigment. In 1845 a Mexican visitor recognized the substance as cinnabar or mercury ore. Soon afterward the New World's richest quicksilver mining district began production, supplying the mercury for the refiners of the California Gold Rush. Its name, New Almaden, echoed the famous Almadén mines of Spain. A hundred years later, the mines had yielded mercury in the amount of more than a million flasks—a volume of the liquid metal weighing 76 pounds. Although mining ended in the 1970s, geologists believe that much undiscovered ore remains.

Let's look at the geologic map of the area (derived from USGS Map OF-98-975).

The New Almaden district runs northwest on Los Capitancillos Ridge from the village of New Almaden. Asterisks mark the four park entrances. Franciscan rock units are fm, melange; fpv, volcanics; gs, greenstone; pink, serpentinite; yellow, silica-carbonate rock; orange, chert. Units with names starting Q, T or K are younger.

It's kind of a mess, and the details are in the caption, but basically Los Capitancillos Ridge is like many other Bay Area mercury sites, an intricate mixture of Franciscan rocks and serpentinite that has been kneaded and heated and injected with metal-bearing fluids. These fluids, derived from magma intrusions, replaced the minerals in the serpentinite and turned it into silica-carbonate rock. The cinnabar lodes, in turn, were emplaced in and near the silica-carbonates. As you hike about the ridge, keep an eye underfoot for the widespread serpentinite.

Serpentinite boulders in a streambed.

Among other things, the park contains mines and machinery spanning a century of progress from traditional techniques of medieval origin to modern American facilities. One mine entrance, the San Cristobal tunnel, has been kept open for a short distance.

San Cristobal tunnel, first opened in 1866.

Go on in and look for the veins in the walls. These are typically filled with quartz or dolomite.

Veins in the San Cristobal tunnel.

Another worthwhile spot is the site of the Buena Vista shaft, the deepest in the district. The foundation of the pumphouse is constructed of large blocks of local sandstone and Sierran granite. It was abandoned in 1893.

The Buena Vista shaft mainly served to dewater the hills and allow neighboring mines to go deeper in search of cinnabar.

Nearby are extensive piles of mine tailings. Although this shaft produced only minor amounts of ore, the rocks themselves are interesting. Remember that collecting rocks and minerals is forbidden. A ranger told me that if people kept taking things home with them, eventually there would be no tailings left. I don't see the problem with that, and if I could make the rules I would give rockhounds access to limited parts of the park.

Don't miss the views of the surrounding territory. The top photo of this post shows the view west to the Sierra Azul, and to the east are views of the Santa Teresa Hills and Diablo Range.

Mount Hamilton's observatories stand out beyond the lower Santa Teresa Hills, site of more mercury mines and sandstone quarries.

The mining museum housed in the Casa Grande, the old manager's residence built in 1854, is full of exhibits and is well worth a visit if you can be there during its brief open hours.

The Casa Grande has rooms full of period furnishings as well as the Quicksilver Mining Museum.

The little museum shop has cinnabar from the Guadalupe Mine for sale. This is the only way you can acquire New Almaden specimens today, unless a dealer is selling off a historic collection at a rock and mineral show.

New Almaden cinnabar is notable for its tiny crystals that give the ore a glittering appearance.

The definitive source for historic and geologic information on the area is the classic US Geological Survey Professional Paper 360, "Geology and Quicksilver Deposits of the New Almaden District."

The new Mercury and Air Toxic Standards announced by EPA administrator Lisa Jackson on December 21st require the electrical industry to limit stack emissions of mercury, arsenic and other toxic pollutants that originate from coal and oil-fired power plants and end up in America's air, water and food. Power plants are the largest source of mercury emissions at around 50 tons of mercury pollution annually. Because the particles are heavier than air, the mercury eventually falls back down and is deposited in rivers, lakes and oceans where it is converted into a more toxic form called methylmercury. This builds up in the food chain, meaning that fish at the top, such as striped bass, blue fin tuna and shark, carry the highest levels of the toxin.

The EPA estimates that 11,000 premature deaths and 130,000 cases of aggravated asthma among children annually by 2016 will be prevented, as well as other health benefits. Women, children and the developing fetus are most at risk for serious health problems resulting from mercury exposure. Between 300,000 and 600,000 of the 4 million babies born in the U.S. each year are exposed to significant amounts of the neurotoxin while in the womb.

Using scrubbers and other well-demonstrated technology, the rule requires power companies install equipment or shut down old plants by 2014 with the possibility of an extension into a fourth year. Seventeen states have already required the industry to apply the clean technology. These older US plants, operating mostly in the Midwest and East, can affect our Bay Area waterways and we will benefit from the new rule. However, most of the mercury in the San Francisco Bay enters from spills, the air, or water runoff from land from natural sources and historical mining.

Mercury levels will remain high in many species of San Francisco Bay and some ocean fish as well as other toxins like PCBs. The California Office of Environmental Health and Hazard Assessment (OEHHA) monitored contaminants in chemical contaminants in fish from the San Francisco Bay.

While the EPA rule is good news for Americans, we must be cautious about what fish and how much fish we consume. Some fish from San Francisco Bay like rockfish and smelt are low in mercury and can be safely eaten. Others like wild king salmon are high in Omega-3s that have been demonstrated to be beneficial to human health. Others like sharks, striped bass and other top predators like swordfish and tuna bio-concentrate mercury and should be avoided, especially by women 18-45 and children under 7 years. The point is to ask where your fish is coming from, how was it caught and how much can you eat. A mercury calculator on the "Got Mercury?" website allows one to calculate how much mercury they are consuming and if it exceeds advisory guidelines produced by the EPA.

The "Got Mercury" Campaign, a project of the Turtle Island Restoration network based in Marin County, is building awareness about toxic mercury in commonly eaten seafood. To reduce risk from mercury exposure, "Got Mercury" is asking the government to increase health advisories and reduce action levels for mercury in fish. The program is also petitioning the FDA to lower the legal mercury action level from 1 part per million (ppm) to 0.5 ppm to be in line with the Environmental Protection Agency’s mercury standards for recreationally caught fish and to require seafood sellers to post mercury in fish warning signs.

Coal still king in Greene County, Pa.

Greene County is in the far southwest corner of Pennsylvania. It is bordered on two sides by West Virginia, and outside of its towns, it is filled with winding country roads flanked by rolling hills. Here, coal still reigns.

Every summer, the county hosts the King Coal Show, a week-long festival with mine rescue contests, a parade, and the Pennsylvania Bituminous Coal Queen Pageant. On a stormy Sunday evening in August, high school girls in evening gowns touted their coal-mining pedigrees along with their good grades and volunteer work. Like many in the area, most could find a great-grandfather, uncle or father who worked in the mines to claim as their connection to the industry.

Here, said County Commissioner Pam Snyder, coal is not a dirty four-letter word.

“Coal means jobs, sustainability on our tax base, families being able to make a good living, raise their children, have decent health-care,” Snyder said.

Today, the coal patch towns that used to dot the county are a thing of the past, but one in five jobs in Greene County is still in mining, and Snyder said a third of the county’s general fund comes from taxes on coal.

Snyder said she does not see anti-coal campaigns as an attack on her community’s way of life. Rather, it is more like a misunderstanding.

“I think if you live in a part of the country where coal has no place and never existed, you are just used to turning on your light switch,” Snyder said, “never giving thought to where that electricity’s being powered from or how it’s getting into (your) home.”

Snyder said she understands why people take their power for granted, but argues those who oppose coal as a power source need to realize how big a role it plays in the nation’s energy portfolio.

‘You need to be mining coal to get paid’

Greene County is home to four major underground mines, including two of the largest in the country, Enlow Fork and Bailey Mine, which together span 22 miles north to south and spill into neighboring West Virginia.

Miners at Consol Energy’s Bailey mine ride an elevator down 700 feet and take a half-hour-long ride on an underground trolley just to get to the job site. There, a massive automated shearing machine lumbers along an exposed wall of coal and slices away at the coal seam. Braces hold the ceiling up until the cutting drums have cleared, then re-position farther down the wall. Chunks periodically fall from the ceiling into a sludge of water and coal dust.

Highly mechanized longwall mining is a far cry from the days of pick-axes and canaries, but mining is still hard, dirty work. Yet, it pays well, an average of almost $90,000, much higher than the county average.

In August, the Obama administration put in place new rules designed to cut the amount of air pollution from coal-fired power plants by more than half, a move the EPA says would reduce asthma, bronchitis and heart attacks in 31 states. The EPA is drafting global warming rules that could hit coal even harder.

Tom Mills, who has been working in Cumberland Mine in Greene County for five years, said he sees new regulations as a threat.

“No matter what you always worry about your job,” Mills said. “You need to be mining coal to get paid. And if they shut these power plants down, these coal-fired power plants, what are they going to use the coal for?”

Like many in the industry, Mills said the future of energy lies in cleaner-burning coal, not in renewable sources.

“Instead of the Sierra Club donating money to shut these places down, maybe they should have donated those millions of dollars to technology to make them burn cleaner,” Mills said.

Mills is not the only one feeling threatened. Billboards touting the reliability and affordability of coal over renewables pepper the highway in Southwestern Pennsylvania, paid for by a group called “Families Organized to Represent the Coal Economy.”

New energy sources in coal’s backyard

Perhaps a more immediate threat than new EPA regulations, though, is the natural gas boom. The tapping of huge reserves in the Marcellus Shale formation right in Greene County and across the region has driven down the price of natural gas and made it more competitive.

Jimmy Brock, chief operating officer for coal for Consol Energy, which owns Bailey mine and also has natural gas operations, said natural gas and new regulations could cut into the market for coal. But if demand drops domestically, he said he is confident the international markets will make up the difference.

“I am not worried for the future of the coal,” Brock said. “I believe coal’s here today, I believe it’ll be here tomorrow, and I believe it’ll be here for many years to come.”

Greene County Commissioner Pam Snyder put it differently. Although she said a serious blow to the coal industry would cripple her county’s economy, “nobody’s pushing panic buttons yet.”

The share of the nation's electricity generated by coal during the first quarter of this year was at its lowest in more than 30 years, due largely to low natural gas prices. But with U.S. demand for electricity expected to grow by about a third in the next quarter century, the industry says King Coal is here to stay.

Bluestem Lake near Lincoln, Nebraska.

Bluestem Lake near Lincoln, Nebraska is five miles north of a coal-fired power plant. It is also one of 85 bodies of water in the state under a consumption advisory because of fish found to have elevated levels of mercury in their tissues. Half of the airborne mercury pollution in the US comes from coal-fired power plants. After years of study and debate, the EPA is planning to announce new limits on mercury from coal plants in November. Ken Winston of the Nebraska Sierra Club believes the agency is doing the right thing.

“When you burn coal, mercury goes up into the atmosphere,” Winston said. “It comes down in the form of rain. Fish eat it. People eat the fish. It can be very damaging and have long term negative impact on the development of children. So it’s something we need to get out of the environment as much as possible.”

The EPA says its proposed new mercury rules could reduce emissions across the country by 91%. Meanwhile, utilities are scrambling to meet other new federal regulations and industry groups are asking the government to slow down. The Nebraska Public Power District operates two coal plants. Under the proposed mercury rule Environmental Manager, Joe Citta, says the utility will need to install equipment that uses activated carbon in order to remove even more mercury than control systems already in place.

Sheldon Station coal fired power plant produces 140 pounds of mercury per year.

“The system is several million dollars,” Citta said. “But what really makes it expensive is the operating cost because activated carbon is rather pricey.”

NPPD will spend 35 million dollars to meet another new regulation reducing smog-forming pollutants that cross state lines. That rule, the Cross-State Air Pollution Rule (CSAPR), was announced in July and takes effect in January. Citta says it requires more cuts than many in the industry expected for pollutants like nitrogen oxides (NOx) and sulfur dioxide (SO2).

“This caught our state, many other states also,” Citta said. When the final rule came out they had reduced those by an additional 40%. Then with only 6 months to comply…We felt the proposed rule was manageable. We would have had to do some things. But they were certainly more achievable than this additional 40% reduction.”

Nebraska utilities feeling rushed by regulation are hoping to get some extra time. The Nebraska Attorney General’s office is working on a lawsuit against the interstate smog rule that a spokesperson says would protect utilities and consumers from costly federal overreach. A bill in the House of Representatives could slow things down by commissioning a study on the economic impact of the EPA’s emissions agenda. Steve Gates of the American Coalition for Clean Coal Energy says it is a reaction to a lot of regulation in a short period of time.

“In a state like Nebraska where 65% of our electricity comes from coal, something is going to happen and the guess is electricity prices go up immediately,” Gates said. “You know, there’s just a lot of economic implications that really should be looked at before we jump into something that no one knows the outcome economically.”

Nebraska rails are a major thoroughfare from Wyoming to power plants in the Midwest and southern Plains. Gates says the state’s economic ties to coal show the advantage of having easy access to inexpensive energy.

“We’re fortunate enough to be in the top ten lowest states for electricity in the country,” Gates said. “What we need to do is find a balance between reducing emissions the best we can while also keeping an eye on what we’re going to do to local economies if we enact something too quickly.”

The EPA claims that the mercury rule will have a positive economic impact in the end by providing health savings of up to $140 billion from reduced asthma, heart disease and other serious ailments. Gates says the EPA underestimates the cumulative impact of multiple rules all coming down at once, particularly in a bad economy. The Sierra Club’s Ken Winston believes power companies are capable of covering costs that they have not paid in the past.

“They can absorb the cost of making these changes much more easily than a person can,” Winston said. “An individual whose child doesn’t develop appropriately because they’ve had mercury poisoning, that’s a life that’s destroyed and we can’t tolerate that.”

Additional Links

• Nebraska Public Power District (NPPD)
• EPA mercury rule
• Nebraska Sierra Club
• Sierra Club – Beyond Coal
• Fish consumption advisories page
• Cross-State Air Pollution Rule (CSAPR)
• Houtson Chronicle – Texas sues EPA to block new pollution rule
• Nebraska AG lawsuit story
• Washington Post – White House threatens veto of House bill to delay EPA pollution rules
• The American Coalition for Clean Coal Electricity (ACCCE)

Cinnabar from Lake County. Photo by Andrew Alden.

It's widely known that California has a mercury problem unlike other parts of the world. We don't produce it and we don't emit much any more, but a lot of old mercury is still lying around from the mining days. How did that happen?

In undisturbed nature, mercury is no more than a very local and very temporary problem. Mercury occurs mostly in sulfide compounds that are concentrated where ore-forming fluids invade metal-rich rocks. Cinnabar and metacinnabar are both mercury sulfide, HgS. Metacinnabar forms at higher temperatures.

Metacinnabar from the Mt. Diablo Mine. Photo by Andrew Alden.

The California Coast Range was a natural place for world-class mercury ore bodies to grow. First, the range has a large amount of metal-rich rocks in the form of serpentinite and its parent rock, peridotite, derived from ancient seafloor. Second, these rocks were cracked and tilted as the Coast Range was built. Third, volcanic activity worked over these rocks, adding heat and chemically active fluids. Thus the source rocks were repeatedly mobilized, attacked and disrupted, a natural refining sequence that at each step concentrated metals.

Serpentinite is a slippery rock that tends to attract faults, which in turn attract fluids. Hot deep fluids replaced the serpentinite with carbonate minerals like calcite, then again with silicate minerals like quartz. As veins of these minerals fan outward they carry mercury with them. Coast Range mercury was originally deposited at high temperatures deep underground, often associated with gold sitting a bit deeper. It remains for erosion to slowly uncover the ores. In coastal California, erosion is quite active as the Coast Range continues to rise.

Wide zones of silica-carbonate alteration dot our mountains and host hundreds of mercury occurrences. The great New Almaden Mine, south of San Jose, exploited a deposit of this type. It was the largest mercury producer in North America, spawning the gold mining industry that followed the placer gold rush of 1849. Cheap, efficient mercury amalgamation was the key to gold production, and New Almaden mercury made it feasible.

Yuba Gold Dredge 17, still working the Sierra gravels, uses mercury amalgamation to capture flour gold. Photo by Andrew Alden.

Volcanic heat also spawns hot-spring activity that can create mercury ore bodies, too. The McLaughlin Mine, north of Lake Berryessa, exploited a hot-spring type deposit yielding gold as well as mercury.

Today the mercury mines of the Bay Area are all closed and being remediated. The New Almaden property is now a county park and the McLaughlin Mine is being carefully restored to a working countryside. Fortunately, mercury can be well controlled if acid mine drainage can be prevented, because cinnabar is poorly soluble except in strongly acid waters. At Clear Lake, the large former Sulphur Bank Mine is slowly getting under control. The privately owned Mount Diablo Mine, where my metacinnabar specimen was collected, is not a threat to spill into local streams although money is needed to fix it for good.

Worldwide, the overwhelmingly largest source of mercury pollution is from the burning of coal. A much smaller source is from oil and gas. Mercury appears to ride along with oil and gas as they trickle from their source rocks upward into the reservoirs we mine for energy. In oil, mercury lives in the tiny metal portion; in gas, mercury is a vapor. Levels in both are in the low parts-per-billion range, although California's oil tends to have relatively high levels. Mercury levels are highest in the dense fraction called petroleum coke, which is burned in place of coal. Even so, coal is far dirtier in terms of mercury, and the Bay Area is spared that insult.

More reading:

• Mercury Cycling and Bioaccumulation in Clear Lake, special issue of Ecological Applications
• Mercury Geoenvironmental Models by James Rytuba (US Geological Survey)

Artist concept of MESSENGER arriving at Mercury.
Credit: NASA

History has been made yet again: NASA's MESSENGER spacecraft is now in orbit around the solar system's innermost planet!

This is exciting to me. When I was a child, Mercury was a contender in my mind for "favorite planet"—right up there with Pluto, being so far away and mysterious, and Uranus, being such a pretty shade of blue. Mind you, that was back before spacecraft had visited any of them….

Being closest to the Sun gave Mercury a claim to fame—just as Venus being the hottest planet or Earth being the home planet or Mars being the red planet or Saturn having rings…okay, they're all special.

At first glance, Mercury presents the appearance of Earth's Moon, but doing just a little math tells you there's more to it. Just divide its mass by its volume and you get 5.43 grams per cubic centimeter—Mercury's average density. That's only a shade less than Earth's average density of 5.51 g/cc, which indicates that Mercury contains more heavy elements than the Moon—elements like iron, for example. (Personally, I suspect there's gold on that thar planet, too….) In fact, after Earth, Mercury is the densest known planet in the solar system. What does it hide under that cratered and radiation-baked surface?

An interesting tidbit about Mercury: because of its high density—because of the amount of material packed within its smallish confines—the surface gravity on Mercury is about the same as on Mars, even though Mars is larger. (Mercury has a diameter of just over 3000 miles, while Mars is about 4200 miles across.) On both worlds, you'd weight about 38% what you weigh on Earth.

And now, Mercury has joined a new club: planets that have been orbited by spacecraft—in this case, NASA's MESSENGER. MESSENGER has been en route to its final orbit around Mercury for over six and a half years. Since its launch on August 3, 2004, MESSENGER has been winding its way through the inner solar system, swinging back past Earth about a year after launch, making a couple of close passes by Venus, then three fly-bys of Mercury itself, before settling into orbit on March 17th.

This long and meandering path was a great fuel saver: by making flybys of planets, MESSENGER's trajectory and speed were altered to make the transition from Earth orbital velocity to a stable orbit around Mercury without burning a lot of fuel to do so. Other spacecraft have used gravitational "slingshot" maneuvers to change direction or gain speed for free, including the Voyagers and New Horizons (on its way to Pluto).

At Mercury, sunlight is up to ten times more intense than at Earth—and since Mercury has no atmosphere to filter out ultraviolet and X-rays, let's just say the sunburn you'd get standing on its surface would be nothing short of lethal. Never mind the lack of air….

To keep cool in the intense solar radiation environment around Mercury, MESSENGER takes advantage of the same physical principle that keeps the dark side of Mercury itself cool (as cold as negative 185 degrees F): insulation. Down on Mercury, the night-time surface is protected from the Sun's intense rays by an entire planet of material. With no atmosphere to trap heat, at night the temperature plummets as heat radiates from rocks and soil directly into space.

MESSENGER possesses a shield: a "sun screen" made of heat-resistant ceramic cloth, situated between the Sun and spacecraft much like someone holding a parasol to stay in the shade.

Poking out from behind its shield, MESSENGER wields two solar panels that provide the spacecraft all of its power—one distinct advantage of the otherwise troublesome intensity of Mercurial sunlight.

Now that MESSENGER is in orbit, what do we hope to discover in the days and months ahead?

Is there ice at the bottom of polar crater floors? How is Mercury's magnetic field generated? Does Mercury have, or did it have, plate tectonics? What's it made of? How does Mercury interact with plasma flowing from the Sun—the solar wind? Are there any strange obelisks on its surface? …to make just a partial list…. Answers to follow (for most of them, anyway).

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Mercury is a poisonous metallic element that is liquid at room temperature.

There's nothing like producing a controversial story on some favorite food group to have a profound effect on one's appetite. I gave up chicken after doing a story on factory farms (I already didn't eat beef or pork or I would have eliminated those as well.) Now, fish, too, has fallen from grace. Ignorance was bliss.

I've known for quite some time that some fish, especially tuna, were high in mercury. But discovering the extent of the problem, and that halibut and sea bass were also on the “do not eat too much of” list, was eye-opening for me. Now I count fish servings like some people count calories. Japanese cuisine, one of my favorites, has lost some of its glow, as well as its frequency in my dining-out plans.

Many of you have practical questions, as did I. How big a crimp does this have to put in my diet? How much is too much? How often is too often? Can I still enjoy that tuna sashimi and not worry about mercury overload?

Because there wasn't time in the QUEST TV segment on mercury in the bay to include information on safe fish eating practices, below are the guidelines, along with web links, to help you get plenty of Omega 3s and still keep your mercury levels low.

Here's what California's Office of Environmental Health Hazard Assessment says about eating fish from the San Francisco Bay and Delta Region.

• Women beyond childbearing age and men should eat no more than two meals per month of San Francisco Bay sport fish, including sturgeon and striped bass caught in the delta. (One meal for an adult is about eight ounces).
• Women beyond childbearing age and men should not eat any striped bass over 35 inches.
• Women of childbearing age, pregnant, nursing mothers, and children should not eat more than one meal of Bay fish per month. In addition, they should not eat any striped bass over 27 inches or any shark.
• This advisory does not apply to salmon, anchovies, herring, and smelt caught in the bay; other sport fish caught in the delta or ocean; or commercial fish.
• Richmond Harbor Channel area: In addition to the above advice, no one should eat any croakers, surfperches, bullheads, gobies or shellfish taken within the Richmond Harbor Channel area because of high levels of chemicals detected there.

Here’s a summary of the joint fish advisory published by the FDA and EPA for women who are pregnant, breastfeeding or may become pregnant and for children. This is a general advisory not exclusive to any water body.

• Do not eat Shark, Swordfish, King Mackerel, or Tilefish because they contain high levels of mercury.
• Eat up to 12 ounces (2 average meals) a week of a variety of fish and shellfish that are lower in mercury. Five of the most commonly eaten fish that are low in mercury are shrimp, canned light tuna, salmon, pollock, and catfish.
• Another commonly eaten fish, albacore ("white") tuna has more mercury than canned light tuna. So, when choosing your two meals of fish and shellfish, eat only up to 6 ounces (one average meal) of albacore tuna per week.
• Check local advisories about the safety of fish caught by family and friends in your local lakes, rivers, and coastal areas. If no advice is available, eat up to 6 ounces (one average meal) per week of fish you catch from local waters, but don't consume any other fish during that week.
• Follow these same recommendations when feeding fish and shellfish to your young child, but serve smaller portions.

Also, check for local advisories for each water body in California that has fish consumption guidelines. They vary by water body.

And lastly, here’s some practical advice from Dr. Jane Hightower, the medical doctor who we feature in the mercury story.

• “If you’re genetically susceptible, it’s really important to know that if you are an autoimmune-prone patient, Lupus, MS, thyroiditis, these kinds of things, then you should not consume mercury on a regular basis or at all. … And then the cardiac patients. You know, mercury can cause a reaction in vessels that leads to inflammation. So you want to have your Omega 3 fatty acids, which is anti-inflammatory. And not have mercury which is pro-inflammatory…. If you want to avoid significant mercury and you just don’t know what the mercury content is in the fish, a rule of thumb is to eat the small fish. Not a piece of the fish. If it comes in a steak, you want to know how big the fish was that the steak came from. You want the whole fish to fit on your plate. Don’t buy a bigger plate. Get a smaller fish. With the exception of salmon. Salmon can have elevated mercury, but very rarely.”

Good luck, good health, and and watch out for bones!




Watch the Mercury in San Francisco Bay television story online.




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Tags: almaden, gold rush, mercury, mining, poison, pollution, total maximum daily load, toxic
]]> http://science.kqed.org/quest/2009/10/06/producers-notes-mercury-in-san-francisco-bay/feed/ 0 37.8627000 -122.318000037.8627000-122.3180000 http://science.kqed.org/quest/2009/06/12/how-toxic-is-a-busted-compact-florescent-bulb/ http://science.kqed.org/quest/2009/06/12/how-toxic-is-a-busted-compact-florescent-bulb/#comments Fri, 12 Jun 2009 23:40:53 +0000 Jim Gunshinan http://www.kqed.org/quest/blog/?p=2786
Which is worse for you, a can of tuna or a broken CFL bulb? Sorry, Charlie… image by Dave LifsonA paper expected to be published in the August issue of the lighting industry journal, LD+A, may quiet some of the controversy over the dangers of mercury in compact fluorescent lights (CFL). I’ve argued in this blog that the cut in mercury emissions from power plants due to the electricity saved when traditional incandescent bulbs are replaced with CFLs, greatly outweighs the amount of mercury that could escape from broken CFLs, plus what is emitted during the making and transportation of CFLs. But the paper, by Robert Clear, Francis Rubinstein, and Jack Howells, who do research at Lawrence Berkeley National Laboratory (LBNL), goes a step farther by showing that even a person who breaks a lamp is more at risk from mercury in the environment than from the mercury in the lamp itself.

The researchers point out that there is a distinction between the kind of mercury that you are exposed to from broken CFLs—elemental mercury—and the mercury emitted from power plant smokestacks after it finds it’s way into waterways and oceans, where it becomes methyl mercury. Methyl mercury accumulates all up the food chain, so that large fish like tuna can contain a lot of it. Methyl mercury crosses the blood-brain barrier and passes through a pregnant woman’s placenta to her fetus. Methyl mercury is responsible for developmental problems, while elemental mercury, which is inhaled, appears to be more of a hazard for adults and children, and only then in the case of severe or prolonged exposures. In most mild cases, when the elemental mercury exposure ends, the bad effects diminish and go away. This is unfortunately not true for the developmental problems caused by methyl mercury.

The startling conclusion of the paper is that in a worse case scenario—you break a CFL in a closed, unventilated room; you vacuum the carpet, throwing mercury into the air; you set the vacuum in a corner; and then sit in the room breathing for eight hours—the amount of mercury exposure is about equivalent to the exposure you’d get from eating a can of Albacore tuna.

Eating a can of tuna has positive health effects as well as the negative health effects from the mercury. There are no positive health effects from a broken CFL, and you can reduce your exposure. The researchers suggest that in the case of a broken CFL, you should immediately open a nearby window. You can limit contamination by gathering up the large pieces of the broken bulb into a bag and set the bag outside. The room should then be left to air out for an hour or so. If the lamp broke on a carpet you can vacuum, but it should be done quickly while the room is being ventilated, the vacuum cleaner should be removed to an outside area, and again the room should be left vacated for an hour or so. Once the vacuum cleaner has cooled, you can empty the contents of the vacuum cleaner bag into the bag with the broken bulb. Take the bag to your nearest recycling center.

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Tags: albacore, cfl, compact flourescent lighting, light bulb, mercury, methyl mercury, tuna
]]> http://science.kqed.org/quest/2009/06/12/how-toxic-is-a-busted-compact-florescent-bulb/feed/ 0 37.8686000 -122.267000037.8686000-122.2670000 http://science.kqed.org/quest/2008/10/22/mercury-messenger-the-view-is-great-wish-you-were-here/ http://science.kqed.org/quest/2008/10/22/mercury-messenger-the-view-is-great-wish-you-were-here/#comments Wed, 22 Oct 2008 16:13:37 +0000 Ben Burress http://www.kqed.org/quest/blog/?p=906 MESSENGER's color filter imaging capability reveals variations
in color on Mercury too subtle for the human eye.
Photo credit: NASA/MESSENGERLike a snow-bird relative vacationing in warmer climate localities and sending back picture postcards of their trip, NASA's MESSENGER spacecraft has made yet another swing past our Solar System's innermost planet, Mercury. But, like the traveler who just can't seem to get enough sightseeing in, this was another whirlwind flyby set to the furious tempo of a camera snapping pics–about 1200 in all…

Did MESSENGER find anything new, since its first flyby back in January? Here are a few highlights:

• Prominent "ejecta" rays streaking out from several large craters–previously revealed only by radar imaging from Earth, now photographed for the first time.

• 30% more of Mercury's largely unexplored surface than had been revealed by the Mariner 10 flybys in the 70's and MESSEGNER's own first flyby last January (spacecraft–namely Mariner 10 and MESSENGER–have now imaged 95% of Mercury's surface).

• "Hyper-color" (my own word) imaging of surface features that reveal variations in color too subtle for the human eye to notice, providing information on soil and rock composition.

I'm a planet junkie–and Mercury has always had a special place in my imagination. One might think of Mercury as the least interesting planet, in our Solar System as well as among dozens of "exoplanet" systems yet discovered. After all, it's a small, dry, cratered, and airless lump of rock and dust, resembling for the most part Earth's Moon. Consider, however, the point of view of someone who's favorite place on Earth is dry, dusty Death Valley, and my enamorment might not come as such a surprise.

In my imagination I see towering cliffs, enormous, deep crevasses, wide, flat dusty plains, bright brights in sunlit patches and dark darks in shadow….

But it's really its differences from Earth that make Mercury such an appealing exotic vision. Being where it is, 36 million miles from the Sun (about a third the Earth-Sun distance), the sunlight striking the Mercurian landscape is six times brighter–imagine that! And not just the visible light spectrum, but all the wavelengths of light the Sun puts out are free to impact Mercury's surface, unimpeded by an atmosphere: infrared, ultraviolet, X-rays, and potent burst of gamma rays rain down intensely on the planet's plains, mountains, and craters.

Speaking of the Sun, its behavior in Mercury's skies is, to say the least, zany. Mercury orbits the Sun in about 88 days (Earth days), but rotates so slowly that a single Mercurian day (the time from one high noon to the next) is about 115 Earth days. Not only does that mean sun-up to sun-down lasts roughly a couple of months, but that Mercury's orbital motion has a greater effect than its rotation on the Sun's apparent motion through its sky. The complicated relationship between Mercury's year and its day also causes the Sun to go "retrograde" at times–that is, periodically halt its progress from one horizon to the other and temporarily go in the opposite direction.

So, our prodigal vacationer MESSENGER has its itinerary straight: a climate with the brightest, warmest sunlight, pristine landscapes, long sunny days, and big skies that perform tricks for its amusement. Now, if only there was a beach…

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Tags: Astronomy, chabot space and science center, kqed, mercury, messenger, nasa, planets, QUEST, Science
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