Newsletter - April 2005
Note: The following summaries are based on articles from the press and from peer-reviewed publications, and they represent the opinions of the original authors. The views of authors expressed herein do not necessarily state or reflect those of the United States Government, and shall not be used for advertising or product endorsement purposes. Reference herein to any specific commercial products, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government.
Current Events, News and Journal Articles
- How Safe is Seafood? New "Seafood Safe" Testing Program and Label to Answer Health Concerns of U.S. Consumers. A seafood distributor, EcoFish, has lauched a new program to help consumers select seafood that is safe by providing of an easy-to-read label that list that critical safety information. The new "Seafood Safe" program and label, the first of its kind in the United States, will assist consumers in making informed decisions when purchasing seafood at the supermarket or in restaurants. Seafood Safe is a comprehensive testing program for two toxic chemicals of concern in seafood, PCBs and mercury. Testing is conducted for the company by independent testing laboratories under the guidance of a scientific advisory panel. Although EcoFish is the first to adopt the Seafood Safe program, the program will be available to the entire seafood industry by the fall of 2005. The Seafood Safe Web site provides meal recommendations for adults and children based on body weight and other factors.
Source: How Safe is Seafood? New "Seafood Safe" Testing Program and Label to Answer Health Concerns of U.S. Consumers. 2005. Business Wire, Feb 22.
- IQ Loss Linked to Mercury Deemed Costly. Researchers at Mount Sinai Center for Children's Health and the Environment reported that lower IQ levels resulting from mercury exposure in utero is estimated to cost the U.S. economy $8.7 billion a year in lost earning potential. The researchers combined results from a number of studies to determine that potentially hundreds of thousands of babies are born every year with lower IQ associated with mercury exposure. Using similar study results that examine the effects of lead exposure on IQ, the Mt. Sinai researchers calculated that even a 1.6 point decline in IQ could cost a person $31,800 in lost lifetime earnings as a result of missed educational opportunities or jobs. The findings, published in Environmental Health Perspectives, are derived in part from data from the Centers for Disease Control and Prevention (CDC), which monitored the frequency of high mercury blood levels in women of childbearing age across the United States. Mount Sinai researchers estimated that from 316,588 to 637,233 children are born each year with umbilical cord blood mercury concentrations linked to IQ loss. The study also found that IQ losses linked to mercury range from 0.20-24 IQ points.
Source: IQ Loss Linked to Mercury Deemed Costly. 2005. Lourenco, H. M., C. Afonso, M.F. Associated Press, March 1.
- Minnesota's Pollution Control Agency Slow to Look into Contamination from 3M Chemical. After the 3M Company discontinued its Scotchgard product in 2000 due to concerns about one of its chemicals, the U.S. Environmental Protection Agency started an investigation in Minnesota, where the chemical was developed; however, the Minnesota Pollution Control Agency (MPCA) waited for two more years before looking into the matter. Scotchgard, one of 3M's premier products, was produced from a chemical that degrades to perfluorooctanyl sulfonate (PFOS), produced at 3M's plant in Decatur, Alabama. 3M also produced perfluorooctanoic acid (PFOA) at its plant in Cottage Grove, Minnesota. Scientists found that PFOS and PFOA do not degrade readily in the environment. PFOS and PFOA remain in the human body for about five years and four years, respectively. This could be a health problem if these chemicals turn out to be toxic in humans. These chemicals have already been shown to cause birth defects and even death in laboratory animals at high doses.
Source: Minnesota's Pollution Control Agency Slow to Look into Contamination from 3M Chemical. 2005. Associated Press, February 24.
- Selenium in water, sediment, plants, invertebrates, and fish in the Blackfoot River drainage. In September 2000, nine stream sites in the Blackfoot River watershed in southeastern Idaho were sampled for water, surficial sediment, aquatic plants, aquatic invertebrates, and fish to determine selenium contamination levels. Water quality parameters (e.g., pH, hardness, and specific conductance) were relatively uniform among all sites. Elevated selenium levels were found in water, sediment, aquatic plants, aquatic invertebrates, and fish from several sites, suggesting deposition in sediments and food web cycling through plants and invertebrates. Selenium levels were of concern in water at eight sites (> 5 mg/L), sediment at three sites (> 2 ppb); in aquatic plants at four sites (> 4 ppb); in aquatic invertebrates at five sites (> 3 ppb); and in fish at seven sites (> 4 ppb in whole body). A hazard assessment of selenium suggested phosphate mining was the apparent source of the selenium, and levels were sufficiently high in several ecosystem components to result in adverse effects to aquatic resources.
Source: Selenium in water, sediment, plants, invertebrates, and fish in the Blackfoot River drainage. Stevens, H.J. and K.J. Buhl. 2005.Water Air and Soil Pollution 159 ( 1): 2-34.
- Survey of omega-3 fatty acid intakes and omega-3 food selections in cardiac patients living in a section of the Midwestern United States. The authors surveyed the omega-3 fatty acid intakes and omega-3 food selections of 36 cardiac patients living in the Midwest. An omega-3 food frequency was developed that included 149 food items, and study participants included cardiac patients from a local heart clinic (n = 36). Dietary omega-3 fatty acid intakes varied from 0.18 - 10.15 g/day. Seafood and fish were the primary food sources of omega-3 fatty acids and were eaten twice a week. Major plant food sources of omega-3 fatty acids consumed included walnuts, flaxseed, canola oil, and soybeans.
Source: Survey of omega-3 fatty acid intakes and omega-3 food selections in cardiac patients living in a section of the Midwestern United States. Kimberly, H., L. Nancy, and E. Sharon. 2004. Nutrition Research 24 (9): 741-747.
- 'School's in' for omega-3. The author discusses the process of fortification of foods in the United States with omega-3 fatty acids. The discussion centers on food fortification with respect to: recognition that in children, deficiencies of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) in diets may delay cognitive development; consumer awareness of the beneficial properties of omega-3 fatty acids; FDA claims that support a link between reductions in risk of coronary heart disease and consumption of foods rich in EPA and DHA; alpha-linolenic acid (found in flax or linseed); certification of menhaden fish oil as a GRAS ingredient; formulation problems associated with fish oils and solutions; and other sources of EPA and DHA in various foods.
Source: 'School's in' for omega-3. Wade, M.A. 2005. Prepared Foods 174 (1):145-146.
- Mercury in commercial fish: optimizing individual choices to reduce risk. The authors examined mercury concentrations in three fish species (tuna, flounder, and bluefish) available in New Jersey stores by sampling in different regions of the state, in communities with different per capita incomes, and in both supermarkets and specialty fish stores. The researchers studied whether mercury levels in New Jersey fish, when compared to data collected nationally by the U.S. Food and Drug Administration (FDA) for the same species, differed based on region of the state, economic neighborhood, or type of store. The researchers found that mercury levels varied significantly by species (tuna contained the highest concentrations, and flounder contained the lowest); there were no significant differences based on the type of store or economic neighborhood; and there was one difference based on region (flounder from fish markets along the Jersey shore had higher mercury concentrations than flounder in other markets). The authors also analyzed mercury levels in other commonly available fish and shellfish species from central New Jersey markets and found significant differences in availability and mercury concentrations among fish and shellfish. Consumers that select fish for availability (present in > 50% of markets) would select flounder, snapper, bluefish, and tuna (highest mercury levels), and those that select based on price would select whiting, porgy, croaker, and bluefish (mean mercury levels < 0.3 ppm). Flounder was the fish with the best availability, cost, and low mercury concentrations. The authors recommended that state health agencies gather information on fish availability in markets, as well as fish preferences data from diverse groups of citizens, and utilize this information to select fish for chemical contaminant analysis.
Source: Mercury in commercial fish: optimizing individual choices to reduce risk. Burger, J., A.H. Stern, and M. Gochfeld. 2005. Environmental Health Perspectives 113 (3): 266-71.
- Mercury and omega-3 fatty acids in retail fish sandwiches. Mercury and fatty acids were measured in fish sandwiches purchased from six retail restaurant chains. Mean mercury concentrations ranged from 5 to 132 ppb; well below the FDA action level (1,000 ppb). Mean concentrations of EPA plus DHA ranged from 91 to 620 mg per sandwich. A 60-kg individual consuming one or two fish sandwiches per week would be exposed to 2 to 40 percent of the reference dose for mercury and would consume 18 to 126 percent of the adequate intake for EPA plus DHA recommended for a pregnant or lactating woman.
Source: Mercury and omega-3 fatty acids in retail fish sandwiches. Shim, S.M., J.A. Lasrado, L.E. Dorworth, and C.R. Santerre. 2005. J Food Prot 68 (3): 633-5.
- A comparison of the non-essential elements cadmium, mercury, and lead found in fish and sediment from Alaska and California. Concentrations of three elements (cadmium, mercury, and lead) were analyzed in sediment and fish from locations in Alaska and California. The results were used to examine differences in bioaccumulation within and between geographic regions. The authors analyzed several tissues from white croaker and English sole in California and flathead sole in Alaska (several other species of invertebrates were analyzed for mercury only). Cadmium levels in fish liver were negatively correlated with sediment levels. No such correlations were detected for mercury and lead. Normalized sediment concentrations for liver and organic carbon were positively correlated, but only for the California sites. Sediment lead levels at the Alaska sites were lower than for the California sites; however, Alaska invertebrates typically accumulated more lead. Lead accumulation was higher in California fish, although ratios of total metal/acid volatile sulfides (AVS) in sediment were one to two orders of magnitude higher for the Alaska sites. Bioaccumulation factors were greatest at relatively clean sites, indicating these metals were more bioavailable at clean sites than from contaminated areas. The authors suggest that differences in fish species are less important than site-specific geochemical features in controlling bioavailability and bioaccumulation.
Source: A comparison of the non-essential elements cadmium, mercury, and lead found in fish and sediment from Alaska and California. Meador, J.P., D.W. Ernest, and A.N. Kagley. 2005. Sci Total Environ 339 (1-3): 189-205.
- Mercury burdens in Chinese mitten crabs (Eriocheir sinensis) in three tributaries of southern San Francisco Bay, California. Chinese mitten crabs, introduced from Asia, were first reported in San Francisco Bay in 1992 and are now widely established in nearly all tributaries to San Francisco Bay. Mitten crabs bioaccumulate heavy metals more than some other crustaceans. Because they are prey for fish, birds, and mammals, and food for humans, their mercury burdens have the potential to impact the ecosystem and public health. The authors assessed the potential implications of mitten crab mercury burdens in three tributary streams in the southern portions of San Francisco Bay and found that total mercury and methylmercury hepatopancreas concentrations did not differ among streams. The maximum levels measured did not exceed the action level of 1 ppm recommended by the FDA. In addition hepatopancreas methylmercury concentrations declined with increased crab size. This finding suggests a possible mechanism for mercury excretion. In addition, predators might reduce mercury exposure if they select larger crabs.
Source: Mercury burdens in Chinese mitten crabs (Eriocheir sinensis) in three tributaries of southern San Francisco Bay, California. Hui, C.A., D. Rudnick, and E. Williams. 2005. Environmental Pollution 133 (3): 481-487.
- Fish consumption: Recommendations versus advisories, can they be reconciled? The American Heart Association (AHA) recommends consumption of at least two servings of fish per week to achieve cardiovascular protective effects. Some fish however, are contaminated with methylmercury, which may counteract the beneficial effect of the omega-3 fatty acids. Numerous state and federal governments have issued advisories for certain fish species, and these mixed messages may create confusion for the both consumers and health professionals. The authors review whether it is possible to follow the AHA recommendation for fish consumption while avoiding the risks associated with consuming mercury in amounts that exceed government thresholds.
Source: Fish consumption: Recommendations versus advisories, can they be reconciled? Smith, K.M. and N.R. Sahyoun. 2005. Nutritional Review 63 (2): 39-46.
- Impact of consumption of freshwater fish on mercury levels in hair, blood, urine, and alveolar air. Fish consumption is the major exposure route for humans to methylmercury. The authors investigated the influence of freshwater fish consumption on mercury concentrations in hair, blood, urine, and end-exhaled (alveolar) air. The cohort consisted of 20 subjects recruited from sport-fishing organizations who ranged in age from 61 to 87 years and were without dental amalgam fillings. Six subjects ate freshwater fish at least once a week and were designated high consumers; eight individuals ate freshwater fish at least once a month, but less than once a week, and were classified as medium consumers; and six subjects were classified as low consumers who consumed no freshwater fish in the past three months. The study found a significant relationship between fish consumption and mercury in all biological media. Among high consumers, median mercury concentrations were 8.6 ppb (blood), 2.4 ppm (hair), 10 pg/L (alveolar air), and 1.1 microg/g creatinine (urine). High consumers had much higher mercury residues in blood (9-fold), hair (7- fold), alveolar air (3-fold), and urine (15-fold) than low-consumers. The blood-hair mercury ratio was 1:270, which agrees with the ratio of 1:250, specified by the World Health Organization (WHO) in 1990.
Impact of consumption of freshwater fish on mercury levels in hair, blood, urine, and alveolar air. Johnsson, C., A. Schutz, and G. Sallsten. 2005. Journal of Toxicology and Environmental Health 68 (2): 129-40.
- Evaluation of a point-of-care blood analyzer and determination of reference ranges for blood parameters in rockfish. The authors compared values of blood parameters in rockfish obtained by use of a point-of-care portable blood analyzer with values determined by a veterinary diagnostic laboratory; calculated reference ranges in black rockfish for several blood parameters; and compared blood parameter values in clinically normal and abnormal fish. The authors examined 41 captive adult black rockfish (Sebastes melanops) and 4 captive adult blue rockfish (S. mystinus). Blood samples were analyzed immediately for a variety of blood parameters with a point-of-care analyzer. Paired blood samples were transported to a veterinary diagnostic laboratory for comparable analyses. The authors reported that data obtained with the point-of-care analyzer were reproducible; however, values for most parameters were significantly different from those obtained by the veterinary diagnostic laboratory. Fish with poor body condition had some blood parameter values lower than values from clinically normal fish. For a large number of clinically normal fish, point-of-care data must be obtained for reference ranges to be calculated; therefore, further evaluation of clinically abnormal fish is necessary to determine the relevance of the resulting data.
Evaluation of a point-of-care blood analyzer and determination of reference ranges for blood parameters in rockfish. Harrenstien, L.A., S.J. Tornquist, T.J. Miller-Morgan, B.G. Fodness, and K.E. Clifford. 2005. Journal of the American Veterinary Medicine Association 226 (2): 255-65.
- Effect of concomitant consumption of fish oil and vitamin E on production of inflammatory cytokines in healthy elderly humans. A beneficial effect of fish oil in reducing inflammatory and cardiovascular diseases may occur in part through fish oil's inhibition of synthesis of pro-inflammatory cytokines. The authors reported that epidemiologic studies have shown an association between increased dietary vitamin E intake and reduced cardiovascular disease risk. This current study was designed to determine the effect of concomitant fish oil and vitamin E intake on interleukin (IL)-1beta, IL-6, and tumor necrosis factor (TNF) alpha production by peripheral blood mononuclear cells. Healthy elderly individuals consumed fish oil with the addition of different doses of vitamin E for three months. Results show that fish oil inhibited production of pro-inflammatory cytokines. Vitamin E did not interfere with this effect of fish oil, but its addition might contribute to the fish oil-induced inhibition of cytokines, especially at the 200 mg/d dose.
Effect of concomitant consumption of fish oil and vitamin E on production of inflammatory cytokines in healthy elderly humans. Wu, D., S.N. Han, M. Meydani, and S.N.Meydani. 2004. Ann N Y Acad Sci 1031:422-4.
- Environmental mercury exposure in children: South China's experience. The authors studied the relationship between dietary habits and environmental mercury exposure in Chinese children. Hair and blood mercury concentrations of children aged 3 years old and above in 2000 were collected for analysis. Sociodemographic data, dietary habits within the last six months, and other risk factors for mercury exposure were collected. Children with blood mercury levels above the toxic range (> 45 nmol/L) and their family members were evaluated further, and their blood and hair mercury concentrations were monitored before and after a three month fishing-moratorium period. A total of 137 Chinese children (mean age, 7.2 years) were recruited. The mean hair and blood mercury levels were 2.2 ppm and 17.6 nmol/L, respectively. In cohort, there was a strong correlation (r = 0.88) between hair and blood mercury levels. Fish consumption frequency correlated with both hair (r = 0.51) and blood (r = 0.54) mercury levels. Children who consumed fish more than three times per week had hair and blood mercury levels that were twice as high as those who consumed fish l to 3 times per week and three times more than those who never consumed fish. Five children and 12 family members had blood mercury levels exceeding the toxic range.
Environmental mercury exposure in children: South China's experience. Ip, P., V. Wong, M. Ho, J. Lee, and W. Wong. 2004. Pediatric Int 46 (6): 715-21.
- Environmental mercury exposure in children: South China's experience. The authors used a previously developed exposure model to assess the effectiveness of various fish advisory scenarios on minimizing mercury blood levels resulting from commercial seafood consumption. The model used predicts mercury (Hg) blood levels in U.S. women of child-bearing age based on the frequency of seafood consumption, meal size consumed, and seafood species consumed. The model was confirmed using National Health and Nutrition Examination Survey (NHANES) blood Hg data. The authors used the model to predict the impact of limiting the amount or seafood species consumed on Hg levels. Various advisory scenarios based on limiting total consumption of seafood and/or eliminating certain species from the diet were simulated. For the baseline model, median (uncertainty) estimates for the 50th, 95th, and 99th per capita population percentiles were 1.25, 8.2, and 16.1 ppb blood Hg, respectively. After restricting seafood consumption to no more than 12 ounces per week, the medians dropped to 1.22, 6.8, and 10.6 ppb blood Hg, respectively. Eliminating species, with average methymercury levels above 0.6 ppm, resulted in only modest reductions in mercury blood levels, as compared to restricted consumption scenarios. Results suggest that for consumers in the high end of the exposure distribution, methylmercury exposure can be more effectively minimized by reducing the meal size and meal frequency (e.g., 12 ounces per week) than by changing the fish species consumed.
An intervention analysis for the reduction of exposure to methylmercury from the consumption of seafood by women of child-bearing age. Carrington, C.D., B. Montwill, and P.M. Bolger. 2004. Regulatory Toxicolology and Pharmacology 40 (3): 272-80.
- Content of mercury and cadmium in fish (Thunnus alalunga) and cephalopods (Eledone moschata) from the south-eastern Mediterranean Sea. No Abstract Available
Pesticide residues in water, sediment, and fish at the Sparta, Illinois, National Guard Armory. Ownby, D. R., T.A. Trimble, K.A. Cole, and M.J. Lydy. 2004. Bulletin of Environmental Contamination and Toxicology 2004 73 (5): 802-809.
- Pesticide residues in water, sediment, and fish at the Sparta, Illinois, National Guard Armory. The authors analyzed the levels of mercury (Hg) and cadmium (Cd) in muscle and liver (hepatopancreas) of albacore tuna (Thunnus alalunga) and horned octopus (Eledone moschata) to determine whether the concentrations exceeded the maximum levels established by the European Commission. Mean mercury and cadmium concentrations (wet weight) were higher in liver (albacore: Hg = 2.41 ppm, Cd = 9.22 ppm; horned octopus: Hg = 0.76 ppm, Cd = 6.72 ppm) than in muscle (albacore: Hg = 1.56 ppm, Cd = 0.05 ppm; horned octopus: Hg = 0.36 ppm, Cd = 0.33 ppm). Mercury concentrations exceeding the 1 ppm legal limit were reported in almost all albacore tuna samples (muscle: 71.4%; liver: 85.7%). For horned octopus, concentrations greater than 0.5 ppm were only observed in the hepatopancreas. In muscle samples, the levels were below this limit for all samples tested. Of the albacore muscle, 42.8% exceeded the proposed tolerance limit for cadmium for human consumption; for horned octopus, the established limit was not exceeded in any sample.
Content of mercury and cadmium in fish (Thunnus alalunga) and cephalopods (Eledone moschata) from the south-eastern Mediterranean Sea. Storelli, M.M. and G.O. Marcotrigiano. 2004. Food Addit Contam 21 (11): 1051-6.
Meetings and Conferences
- World Recreational Fisheries Conference. June 12-16, 2005, Trondheim, Norway. http://www4.nina.no/WRFC2005/htm/startside.htm
- Total Maximum Daily Load 2005. June 26-29, 2005, Philadelphia, PA. http://www.wef.org/conferences/TMDL05.jhtml
- National Environmental Health Association. June 26-29, 2005, Providence, RI. http://www.neha.org/AEC/2005/
- American Fisheries Society 135th Annual Meeting. The 135th Annual Meeting of the AFS will be held at the Egan Convention Center and Performing Arts Center in Anchorage, Alaska September 11-15, 2005. The meeting's theme will be "Creating A Fisheries Mosaic: Connections Across Jurisdictions, Disciplines, and Cultures." Get more information and register here: http://www.wdafs.org/Anchorage2005/index.htm
- 2005 National Forum on Contaminants in Fish. The 2005 Fish Forum is sponsored by the U.S. Environmental Protection Agency and the Maryland Department of the Environment. It will be held in Baltimore, Maryland, September 18-21, 2005. Get more information and register here: http://epa.gov/ost/fish/forum/2005/
- Society of Environmental Toxicology and Chemistry (SETAC). November 13-17, 2005, Baltimore, MD. For more information see http://www.setac.org/htdocs/who_guna.html
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