9 resultados para flame retardant additives

em Aquatic Commons


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NOAA’s Mussel Watch Program was designed to monitor the status and trends of chemical contamination of U.S. coastal waters, including the Great Lakes. The Program began in 1986 and is one of the longest running, continuous coastal monitoring programs that is national in scope. NOAA established Mussel Watch in response to a legislative mandate under Section 202 of Title II of the Marine Protection, Research and Sanctuaries Act (MPRSA) (33 USC 1442). In addition to monitoring contaminants throughout the Nation’s coastal shores, Mussel Watch stores samples in a specimen bank so that trends can be determined retrospectively for new and emerging contaminants of concern. In recent years, flame retardant chemicals, known as polybrominated diphenyl ethers (PBDEs), have generated international concern over their widespread distribution in the environment, their potential to bioaccumulate in humans and wildlife, and concern for suspected adverse human health effects. The Mussel Watch Program, with additional funding provided by NOAA’s Oceans and Human Health Initiative, conducted a study of PBDEs in bivalve tissues and sediments. This report, which represents the first national assessment of PBDEs in the U.S. coastal zone, shows that they are widely distributed. PBDE concentrations in both sediment and bivalve tissue correlate with human population density along the U.S. coastline. The national and watershed perspectives given in this report are intended to support research, local monitoring, resource management, and policy decisions concerning these contaminants.

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Executive Summary: Information found in this report covers the years 1986 through 2005. Mussel Watch began monitoring a suite of trace metals and organic contaminants such as DDT, PCBs and PAHs. Through time additional chemicals were added, and today approximately 140 analytes are monitored. The Mussel Watch Program is the longest running estuarine and coastal pollutant monitoring effort conducted in the United States that is national in scope each year. Hundreds of scientific journal articles and technical reports based on Mussel Watch data have been written; however, this report is the first that presents local, regional and national findings across all years in a Quick Reference format, suitable for use by policy makers, scientists, resource managers and the general public. Pollution often starts at the local scale where high concentrations point to a specific source of contamination, yet some contaminants such as PCBs are atmospherically transported across regional and national scales, resulting in contamination far from their origin. Findings presented here showed few national trends for trace metals and decreasing trends for most organic contaminants; however, a wide variety of trends, both increasing and decreasing, emerge at regional and local levels. For most organic contaminants, trends have resulted from state and federal regulation. The highest concentrations for both metal and organic contaminants are found near urban and industrial areas. In addition to monitoring throughout the nation’s coastal shores and Great Lakes, Mussel Watch samples are stored in a specimen bank so that trends can be determined retrospectively for new and emerging contaminants of concern. For example, there is heightened awareness of a group of flame retardants that are finding their way into the marine environment. These compounds, known as polybrominated diphenyl ethers (PBDEs), are now being studied using historic samples from the specimen bank and current samples to determine their spatial distribution. We will continue to use this kind of investigation to assess new contaminant threats. We hope you find this document to be valuable, and that you continue to look towards the Mussel Watch Program for information on the condition of your coastal waters. (PDF contains 118 pages)

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Marine mammals accumulate heavy metals in their tissues at different concentrations according to trophic levels and environmental conditions. The franciscana (Pontoporia blainvillei) is a small coastal species inhabiting the marine and estuarine areas of the Southwestern Atlantic Ocean. Its diet includes numerous species of small fish, squid and crustaceans. The aims of this study were to (i) assess the heavy metal concentration and burden distribution in different franciscana age classes and sex, and to (ii) evaluate both the accumulation processes and the transplacental transference of zinc, cadmium, copper and total mercury. Heavy metal concentrations (wet weight) were determined in eighteen dolphins by Atomic Absorption Spectrophotometry (AAS), by the cold vapour technique (mercury) or with air/acetylene flame (cadmium, zinc and copper). Liver showed the highest concentrations of mercury (max. 8.8 mg/g), zinc (max. 29.7 mg/g) and copper (max. 19.0 mg/g), whereas the highest cadmium concentrations (max. 6.7 mg/g) were found in kidney. Adults contained the highest concentrations for all heavy metals, followed by juveniles and calves in decreasing order, suggesting an age-related accumulation. No differences (p<0.05) were found between sexes within each age class. Organ burden distribution followed the same pattern for all metals and age classes: liver tissues contained maximum burdens. Mercury concentrations were higher than those of cadmium in both foetuses and newborns; and neither metal could be detected in the foetus. The analysed data suggested differences in the placental transference between metals, being significant for mercury and almost null in the case of cadmium. We can conclude that franciscana accumulates heavy metals and, due to its coastal distribution, it may be considered as a biomonitor of its environment. SPANISH: Los mamíferos marinos acumulan metales pesados en sus tejidos cuyas concentraciones están en relación con su nivel trófico y las condiciones ambientales. La franciscana (Pontoporia blainvillei) es una especie costera que habita áreas marinas y estuariales en el Atlántico Sudoccidental. Su dieta está constituída por peces, como item alimentario principal, calamares y crustáceos. El objetivo del presente trabajo es estudiar la distribución de metales pesados en diferentes clases de edad y en ambos sexos, evaluando procesos de acumulación y cargas de cadmio, mercurio total, cinc y cobre. Las concentraciones de metales pesados (en peso húmedo) fueron determinadas en dieciocho delfines por Espectrofotometría de Absorción Atómica (EAA), usando la técnica de vapor frío (mercurio) o llama de aire/acetileno (cadmio, cinc y cobre). El hígado presentó las concentraciones más altas de mercurio (máx. 8,8 mg/g), cinc (máx. 29,7 mg/g) y cobre (máx. 19,0 mg/g), mientras que las más altas de cadmio (máx. 6,7 mg/g) fueron encontradas en el riñón. Los adultos presentaron los niveles más altos, presentando los juveniles y cachorros concentraciones menores, lo cual sugirió una acumulación con la edad. No se encontraron diferencias significativas (p < 0,05) entre sexos dentro de cada clase de edad. Las cargas de metales pesados en los órganos presentaron la misma disribución para todos los metales y clases de edad. Los valores más altos fueron encontrados en el hígado, incluyendo los correspondientes a cadmio. Las concentraciones de mercurio y cadmio fueron no detectables en el feto, mientras que las de mercurio fueron superiores a las de cadmio en los cachorros. Los datos encontrados en el feto sugieren una transferencia nula a través de la placenta. Podemos concluir que P.blainvillei acumula metales pesados en sus tejidos y debido a su distribución costera, esta especie puede ser considerada como un biomonitor de su ambiente.

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Kurzfassung Der Handel mit tiefgefrorenen Kammmuscheln (Pectinidae) hat in den letzten Jahren deutlich zugenommen und ist von der Jakobsmuschel (Pecten maximus) auf eine Reihe weiterer Spezies erweitert worden. Neben nicht zutreffender Handelsbezeichnung fällt diese Erzeugnisgruppe immer wieder durch einen erhöhten Wasserzusatz negativ auf. Es wurde die Zusammensetzung des Muskelfleisches von Produkten aus dem deutschen Handel bestimmt und das Wasser zu Protein- Verhältnis (W/P) berechnet. Eine erhebliche Zahl von Proben hatte hohe Wassergehalte und ein W/P Verhältnis > 5. Dies betraf insbesondere die Tiefseescallop (Placopecten magellanicus) und die Japanische Kammmuschel (Mizuhopecten yessoensis). In den meisten Fällen wurden Zusatzstoffe nachgewiesen, obwohl die gesetzlich vorgeschriebene Deklaration fehlte. Abstract The market share of quick-frozen scallops (Pectinidae) has increased significantly in recent years and has been extended besides the king scallop (Pecten maximus) to a variety of other species. Apart from an incorrect labeling this product group stands out for often excessively high water addition. The composition of the muscle meat and the water to protein ratio (W/P) was determined in samples from the German retail. The results showed that a considerable number of samples had very high moisture contents and W/P ratios > 5. These facts were mainly true for Placopecten magellanicus and Mizuhopecten yessoensis. There was no conformity with the prescribed declaration of food additives.

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The paper gives an account of the types of blackening associated with canned prawn in brine and their control. It was found that blackening caused by iron sulphide could be controlled by maintaining proper titratable acidity of fill brine in cans. The paper also elaborates on the factors responsible for or governing this critical titratable acidity. In regard to copper sulphide blackening, control was found to be difficult by maintaining the acidity or by additives such as EDTA when the copper content in the material went above the critical level.

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Biological studies and heavy metal (Ni, v, Fe, Pb,Cd) determination in liver, gonad and muscle of Scomberomorus commerson were carried out from Oct 2006 to Sept 2007 in Hormozgan coastal waters. 599 Samples were gutted for reproduction and nutrition studies, fork length and weight were measured to nearest cm and g respectively. Meanwhile 40 samples were also investigated for heavy metal studies. All specimens were collected from two major landing sites (Bandar Lengeh & Bandar Abbas). Minimums & maximum fork length & weight were 29, 128 cm & 235 and 15350 g respectively.Isometric growth was shown according to our study and b was estimated 2.9 (overall), 2.91(male) & 2.89 (female). The average relative gut length was 0.52± 0.007 and it was determined that S. commerson is a carnivorous. More than 99 percent of gut content was different teleost fishes. Gastro somatic index had two peaks in Nov & Jan (before spawning) and with a decreased trend in July, the spawning period. Occurrence of empty stomach was estimated % 65.77. Maximum amount of condition factor was in Dec. Spawning season was started from June. The average of Absolute & relative fecundity (to weight unit) was 1217149±179315 and 178.2±15.58 respectively. Lm50% was estimated 75 cm for females. Sex ratio was 0.97: 1 (male: female). Chi- Square test showed no significant difference (p>0.05). Maximum amount of hepatosomatic index was estimated in March.Metal concentrations were determined using either Flame Atomic Absorption Spectroscopy (for Fe) or Graphite Furnace Atomic Absorption Spectroscopy (for Pb,Cd,Ni and V). The mean concentration (μg/g dry weight)of Pb,Cd,Ni,V and Fe in the liver were 0.0309, 0.0268, 0.0672, 0.0077, 2.5159 in the gonad 0.0440 ,0.0295, 0.1096, 0.0000, 1.4449 and in the muscle 0.0244, 0.0324, 0.0656, 0.0128, 1.6138 respectively. The maximum metal concentrations were below the maximum permissible limits for human consumption recommended by the USEPA, WHO and the UK. The results of Kendall's Tau-b correlation coefficient were as follows: The Liver tissue: There were significant positive linear relationships between accumulation of V, Fe, and Pb with Fork length, Pb and Fe with weight, GSI with Pb, Cd, V and 109 Fe, and a negative linear relationships between HSI with accumulation of V and Fe, Fork length, weight and GSI. The Gonad tissue: There were significant positive linear relationships between GSI with accumulation of Pb, Cd, Fe, Fork length and weight, a negative linear relationship between HSI with Fork length, weight and GSI. The Muscle tissue: There were significant positive linear relationships between accumulations of V, Fe with Fork length and weight factors and as well as GSI with Cd, V, Fe, Pb, Fork length and weight,a negative linear relationship between HSI with Fork length, weight, Cd, Fe and GSI. The results of Mann-Whitney U tests (P≤0.05) show that there were significant differences between summer and autumn from heavy metal contents in the studied tissues point of view. The only exceptions were for Ni in the liver, gonads and muscle and as well as there were significant differences between male and female from heavy metal contents in the studied tissues. The only exceptions were for Pb in muscle, Ni in liver, gonad and muscle, V in muscle, and Cd and Fe in gonads.

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There is an increasing demand in developing newer and safer methods in preserving food products.Among which herbal additives seem to attract evermore attention recently.the major advantage of herbal additives is due to their favorable aroma besides their antimicrobial effects and less expensive than chemical additives. Zataria multiflora Boiss is a native Iranian herb which is used vastly as a food preserver essential oils and also medical usage. Metabolites of harmless bacteria, such as Nisin are also known to be safe preservatives that have antimicrobial activity. However to establish the usefulness of natural antimicrobial preservatives, they must be evaluated alone and in combination with other preservation factors to determine whether there are synergistic effects in rigid media . In this study were evaluated the effects of different concentrations of Zataria multiflora (EO 0, 0.005, 0.015, 0.045, 0.135, 0.405 ,0.810 %) and Nisin(0, 0.15, 0.25, 0.75 μg/ml) and Storage time (up to 21 days) on growth of Staphylococcus aureus ATCC 6538 in a food model system(light salted fish of silver carp, Hypophthalmichthys molitrix). The results on growth of S. aureus were evaluated using SPSS 15.0 statistical software (SPSS 15.0 for windows, SPSS Inc.) and analyzed the logarithm of total count of the bacteria by Tukey Test. Results were considered statistically significant when P≤0.05. The growth of Staphylococcus aureus was affected significantly(P<0.05) by EO and Nisin and also combinations of EO and Nisin. Samples treated with 0.135, 0.405 and 0.810% of thyme essential oil showed a significant decrease on the growth of the bacteria compared with an treated samples(P<0.05). No significant difference was seen on the growth of S.aureus in samples treated with lower concentrations of Z.multiflora(below 0.045%) and untreated group(P>0.05). The most inhibitory effects were seen in samples treated with 0.405% and 0.810% of thyme essential oil until 9 and 12 days after storage,respectively. Also there was significant inhibtory effect(P<0.05) in different concentration of nisin on the organism compared with an treated samples. The synergism effects of the Eo and nisin on the growth rate of the bacteria was significant (P<0.05) compared with untreated samples and samples treated with the Eo or nisin, only. Synergismic effects was observed at concentration of 0.405 and 0.810% of Z. multiflora essential oil with 0.25 μg/ml Nisin, respectively until 15 days after storage. As expected it is preferred to apply the least possible amounts of additives in food preserving that not only are effective and safe but are economically justifiable.