at Mandinga Lagoon, Veracruz, Mexico
Contents
1. In addition the presence of pollution related events have been demonstrated and the levels of pollutants have been assessed this data has shown that heavy metals mainly Cr Cd and Pb as well as hydrocarbons and pesticides stand out caused by the runoff of household and industrial discharge in the area Villanueva amp Botello 1998 Pollution monitoring in aquatic systems has been limited to determining the pollutant levels in the tissues of organisms with little attention to the physical alterations produced by them Gold Bouchot et al 1997 However some authors believe that metal concentrations in the biota are better indicators of the biologi cal impact than the environmental concentra tions because the organisms incorporate the Rev Biol Trop Int J Trop Biol ISSN 0034 7744 Vol 57 4 955 962 December 2009 955 contaminants into their bioavailable fraction Borgmann amp Norwood 2002 Therefore the oyster Crassostrea virginica has been proposed for the study of the integration of contaminants Luna et al 2002 Physiological changes in bivalves are a sign of alterations in the rates of filtration feeding growth respiration and reproduction as well as in changes in their metabolic and biochemical parameters Chavin 1973 Assessment of changes produced by pol lutants in organs tissues can be done before an irreversible effect appears on the biota becom ing an alarm system of great relevance i2. 1990 The nature of the diges tive gland lesions suggests a prolonged contact with the pollutants through the oral route and the inability to eliminate them The histopatho logical observations can be related to stressing environmental factors such as temperature salinity and metal concentrations in the water and or sediment Winstead 1998 Damage was associated with metal concentrations in the following order Pb gt Cd gt Cr however there are other pollutants not considered in this study that could be affecting the tissues The histo pathological analysis suggests a recovery of tissues and a greater activation of the detoxifi cation processes in C virginica It is necessary to continue assessing the detoxification process in the laboratory and pursues the analysis of further tissue regeneration We suggest that the rainy season fosters resuspension of Cr and Cd from the sediment which could be the cause of the concentrations found in the water In contrast during the first semester of the year the high concentrations of Cr Cd and Pb in the sediment can be related to the bioaccumulation of these metals in the oyster The concentrations of metals and their effects on bivalves are risk indicators there fore frequent monitoring and the application of measures to improve the quality of the system under study are of great relevance This study shows that the combined use of metal determination and histological bio marker
3. 2009
4. adverse biological effects within ranges of chemical concentrations in marine and estuarine sediments Environ Manag 19 81 97 Lucas A amp P G Beninger 1985 The use of physiological condition indexes in marine bivalve aquaculture Aquaculture 44 187 200 Luna M V O Rend n amp L G Alpuche 2002 Presencia de plomo en agua y osti n en las lagunas de Alva rado y la Mancha p 96 111 Jn A P Guzm n B C Quiroga L C Diaz C D Fuentes M C Contreras amp G Silva L pez eds La pesca en Veracruz y sus perspectivas de desarrollo SAGARPA UV Veracruz Mexico Malo B A 1977 Partial extraction of metals from aquatic sediments Environ Sci Technol 11 277 282 Mann R 1978 A comparison of morphometric biochemi cal and physiological indexes of condition in marine bivalve molluscs p 484 497 In J H Thorp amp J W Gibbons eds Energy and environmental stress in aquatic systems Washington USA Nauen C C 1983 Compilation of legal limits for hazar dous substances in fish and fishery products FAO Rome Italy Paez Osuna F J I Osuna Lopez G Izaguirre Fierro amp H M Zazueta Padilla 1993 Heavy metals in oysters from a subtropical coastal lagoon associated with an agricultural drainage basin Bull Environ Contam Toxicol 50 696 702 Palacios Fest M amp R Vargas Rancel 2002 Pesqueria de ostion p 96 111 Jn A P Guzman B C Quiroga L C Diaz C D Fuentes M C Contreras
5. amp G Silva Lopez eds La pesca en Veracruz y sus perspectivas de desarrollo SAGARPA UV Mexico Rainbow P S D J H Phillips amp M H Depledge 1990 The significance of trace metal concentrations in marine invertebrates a need for laboratory investi gation of accumulation strategies Mar Pollut Bull 21 321 324 SEPESCA Secretaria de Pesca 1988 Manual T cnico para la operaci n de centros acu cola productores de ostion SEPESCA Mexico Shumway S E amp R K Koehn 1982 Oxygen consump tion in the american oyster Crassostrea virginica Mar Ecol Prog Ser 9 59 68 Sobrino Figueroa A S C Caceres Martinez A V Botello amp G Nunez Nogueira 2007 Effect of cadmium chromium lead and metal mixtures on survival and growth of juveniles of the scallop Argopecten ven tricosus Sowerby II 1842 J Environ Sci Health Tox Hazard Subst Environ Eng 42 1443 1447 Villanueva S F amp A V Botello 1998 Metal pollution in coastal areas of Mexico Rev Environ Contam Toxicol 157 53 94 Winstead J T 1998 A histological study of digestive tubules in intertidal and subtidal oysters Crassostrea virginica collected at high and low tides J Shellfish Res 17 275 279 Zaroogian G amp P Yevich 1994 The nature and function of the brown cell in Crassostrea virginica Mar Envi ron Res 37 355 373 962 Rev Biol Trop Int J Trop Biol ISSN 0034 7744 Vol 57 4 955 962 December
6. 50 1 00 13 00 D L Detection limit Cd 0 236ug g Pb 0 119ug g Cr 0 034ug g L M P Maximum permissible limits F A O Nauen 1983 NOM 031 SSA1 1993 Level of concentration ug g Critical levels for consumption of bivalve molluscs Sediment values producing biological effects ERL 22 S D Standard Deviation Rev Biol Trop Int J Trop Biol ISSN 0034 7744 Vol 57 4 955 962 December 2009 957 Cadmium H Lead O Chromium Metal in water mg L March 03 June 03 October 03 January 04 May 04 Colecting time month year Fig 1 Cd Pb and Cr concentrations in the water of the Mandinga Lagoon Veracruz Mexico Cadmium H Lead O Chromium Metal in sediment ug g March 03 June 03 October 03 January 04 May 04 Colecting time month year Fig 2 Concentration of metal in the sediment of the Mandinga Lagoon Veracruz Mexico 958 Rev Biol Trop Int J Trop Biol ISSN 0034 7744 Vol 57 4 955 962 December 2009 March and June 2003 respectively exceed ing the MPL The highest metal concentrations recorded were for oysters collected in June with high temperatures and low water levels corresponding to the end of the dry season Figure 3 shows the concentrations and the per manence of Pb and Cd recorded in the oyster along the annual cycle The matrix correlating the biometric param eters length weight and condition index
7. Effects of heavy metals on the oyster Crassostrea virginica at Mandinga Lagoon Veracruz Mexico X Guzman Garcia A V Botello L Martinez Tabche amp H Gonzalez Marquez 1 Laboratory of Ecotoxicology Hidrobiology Departament UAM I Av San Rafael Atlixco No 186 Col Vicentina Iztapalapa C P 09340 Mexico Fax 5804 4738 xgg xanun uam mx 2 Marine Pollution Laboratory Instituto de Ciencias del Mar y Limnologia UNAM Mexico 3 Laboratory of Gen Expression Health Sciences UAM I Av San Rafael Atlixco No 186 Col Vicentina Iztapalapa C P 09340 Mexico 4 Laboratory of Aquatic Toxicology Pharmacy Departament ENCB IPN Mexico Received 15 V 2008 Corrected 05 III 2009 Accepted 07 IV 2009 Abstract The Mandinga Lagoon in the Mexican State of Veracruz is an important ecological zone that pro duces 32 of the oyster output in the state of Veracruz the main oyster producer in Mexico Samples of water sediment and oysters were collected in 2003 and 2004 to study heavy metal pollution Metal concentrations were determined in water soil and oyster tissues from fresh and detoxified Crassostrea virginica and histology samples were analyzed Metal Cr Cd and Pb concentrations in water were within the Mexican legal limits The recorded values in sediments corresponded to those not producing biological effects ERL In the tissues the highest concentrations corresponded to Pb above 5 84 ugg dry weight d w C
8. d was of 2 23 ugg d w and Cr above 6 ugg d w The metal levels detected in oysters exceeded the maximum permissible limits MPL for Cd and Pb and oysters were unable to eliminate the concentrations of the bioaccumulated metals during the detoxification stage The histopathological analysis revealed lesions in the digestive gland edema atrophy of epithelia in the digestive tubules the presence of brown vesicles hemocytic reaction and necrosis During detoxification a higher number of epithelia were observed in the tubules as well as an increase in brown vesicles and hemocytic reaction Forty seven percent of oysters presented histopathological lesions related to metal concentrations It is important to monitor metal concentrations to detect the source of pollution andto evaluate the effects on organisms to establish culture areas and adequate criteria for the exploitation of such an important fishery resource Rev Biol Trop 57 4 955 962 Epub 2009 December 01 Key words cadmium chromium heavy metals histopathological damage oyster The Mandinga Lagoon in the Mexican State of Veracruz is an important ecological zone which in economical terms sustains a high oyster production as it contributes 32 of the oyster production in the whole state of Veracruz the first oyster producer in Mexico Reports indicate that the oyster production markedly decreased in this region from 1991 to 1996 Palacios Fest amp Vargas Rancel 2002
9. er 2009 Winstead 1998 already reported atrophy of the digestive tubules and loss of epithelia as indicators of stress Zaroogian amp Yevich 1994 reported an increase in the number of brown cells related to the inflammatory response Results in this study suggest that both the pres ence of brown vesicles and the hemocytic reac tion are specific responses of the detoxification process and tissue recovery Other authors have pointed out that the appearance and increase in brown vesicles together with hemocytes at the inflammation site represent mechanisms of pollutant incorporation accumulation and detoxification Engel 1999 This metal generally produces saturation responses which could explain why the levels acquired in the lagoon were not eliminated during the detoxification periods tested despite the fact that the mean life span of Cd under laboratory conditions has been estimated to be 21 days Guzman Garcia 2001 Other authors such as Greig amp Wenzloff 1978 stated that the organisms subjected to depuration from a polluted natural environment to a clean one reduce their depuration rate because metal lothioneins proteins with high affinity for Cd are able to bind the metal and accumulate it in amorphous granules brown vesicles inside the cells in a non toxic manner In the case of bivalves accumulation of metals is produced through feeding by incor porating the bioavailable forms of the metal Rainbow et al
10. evels recom mended by the Mexican legislation Table 2 except in October when Cd water levels of 1 86 mg L were recorded exceeding the maxi mum permissible limit MPL Cr levels were 0 93 mgeL very close to the MPL These findings could be due to removal of pollutants during the rainy season Fig 1 In the sediment the recorded metal values did not reach biological effect levels ERL Cr levels reached 40ugeg which are below those reported to generate biological effects Howev er in March and June Cd levels reached 0 97 and 1 24ugeg respectively which exceeded the ERL concentrations proposed by Long et al 1995 Fig 2 Average metal concentrations in the oyster were 2 23ugeg d w for Cd and 5 84 ugeg d w for Pb 13 41 and 18ugeg dw for Cr TABLE 2 Concentration of metals in water sediment and oysters from the Mandinga Lagoon Veracruz Mexico Dae Water mg L Sediment ug g Oyster ug g d w Cd Pb Gr Cd Pb Ge Cd Pb Gr March 2003 0 02 0 23 0 32 0 97 26 59 29 81 0 95 4 11 18 72 June 2003 0 07 0 25 0 19 1 24 22 27 44 28 6 23 12 01 13 41 October 2003 1 86 D L 0 93 D L 29 18 18 71 0 35 4 12 DL January 2004 D L 2 59 D L D L 4 90 3 09 2 89 4 91 DL May 2004 D L 3 14 D L D L 3 00 1 34 0 71 4 04 D L Average 0 39 1 24 0 28 0 44 17 19 19 44 2 23 5 84 6 43 S D 0 73 1 33 0 34 0 54 11 05 16 24 2 18 3 10 8 04 L M P 0 9 6 00 1 00 1 20 46 70 81 00 0
11. inger 1985 The functional relation was calculated from an average of the variables to minimize the influence of abiotic variables and biotic fac tors Krishnakumar et al 1994 Contingency tables and correlation indices were also calcu lated Everitt 1992 RESULTS Metals determination and biometric parameters Table shows the average values of salinity shell length fresh tissue weight and 956 Rev Biol Trop Int J Trop Biol ISSN 0034 7744 Vol 57 4 955 962 December 2009 TABLE 1 Average of physicochemical parameters and biometrics of the collected oysters Mandinga Lagoon Veracruz Mexico Physicochemical Biometric Sampling Salinity Dissolved oxygen Temperature Length Weight Condition o EP mg L CC mm g Index March 2003 24 0 7 2 9 6 28 5 6 6 45 136 June 2003 30 0 7 6 7 0 31 0 7 2 10 7 285 October 2003 22 3 7 8 6 6 25 0 6 8 15 2 276 January 2004 12 0 7 5 7 0 29 4 7 6 4 3 236 May 2004 22 3 8 3 7 0 24 5 6 6 9 0 194 e Condition Index 90 normal 120 high 70 80 low e Physicochemical values are mean of 3 independent samples Biometrics values are mean of 40 measurements condition index The lower weight oysters were collected in March 2003 and January 2004 the remaining biometric parameters were similar during all sample collections and their weights and indexes were acceptable from the allomet ric point of view Metal concentrations in the water of the lagoon remained within the l
12. led damage in near 50 of the oysters digestive tract digestive diver ticulum gonad and connective tissue Edema hyperplasia of epithelial cells in the tubules presence of brown vesicles and an increase in hemocytes and necrosis correlated with environmental pollutants such as Cd r 0 63 a 0 67 Pb r 0 67 a 0 67 and Cr 1 0 57 a Cadmium H Lead Chromium January 04 May 04 Colecting time month year Fig 3 Concentration of metals in the tissue of the oyster Crassostrea virginica Rev Biol Trop Int J Trop Biol ISSN 0034 7744 Vol 57 4 955 962 December 2009 959 0 67 Figure 4 shows lesions of the digestive gland loss of epithelia of the tubules Fig 4a brown vesicles present in the connective tissue Fig 4b and hemocyte infiltration Fig 4c d The damaged organisms presented atrophy of epithelia in more than 80 of the tubules however in a small percentage of tubules 5 epithelia persisted The prevalence of these lesions was evalu ated in organisms subjected to detoxification observing a larger number of tubule epithelia cells and brown vesicles in the connective tissue surrounding the tubules as well as an increase in the hemocytic response with respect to the depuration time At day 21of the depuration period the increase in tubules with epithelia was 11 brown vesicles increased from 32 in natural organisms to more than 60 in the organisms subjected t
13. n protecting species as well as the environment Hence the aim of this study was to determine the levels of toxic metals Pb Cr and Cd in the water sediment and oyster of the Mand inga Lagoon in Veracruz and to determine their histopathological effects on natural oysters and on oysters subjected to detoxification under laboratory conditions MATERIALS AND METHODS This study was performed in the Mandinga lagoon located in the Gulf of Mexico in the south of the State of Veracruz between paral lels 19 00 to 19 06 N and meridians 96 02 to 96 06 W Samples of water sediment and oysters were collected in March June and October 2003 and in January and May 2004 in three different locations In each 15 oysters were collected for the determination of metals Cr Cd and Pb 15 for histopathological studies 20 for biometric studies and 40 were trans ported to the laboratory for their detoxification and evaluation of the histopathological changes and metals content The oysters transported to the laboratory were placed in four 40 L experimental devices for 504 h with artificial Instant Ocean water Shumway amp Koehn 1982 they were fed with laboratory cultures of Tetraselmis suecica from 1 to 15 million cells mL SEPESCA Secretaria de Pesca 1988 Castrej n et al 1994 and were kept under optimal conditions During the detoxification period the pH 7 9 temperature 25 C salinity 22 ppm feedi
14. ng 10 000 cel mL dissolved oxygen 7 3 mg L and ammonium content NH 4 8 uM L were continuously monitored and kept constant For the histological techniques three oys ter were collected every 72 hours fixed in 10 formalin for 24h then included in paraf fin tissue processor Leica TP1020 inclusion center Leica EG1140H and three 9um serial sections were done with a rotator microtome Microm Zeiss model HM 315 Assessments were focused on the digestive system the digestive gland the gonad and the connective tissue preparations were hematoxylin eosin stained Howard amp Smith 1983 For metal determinations organisms were weighed and dehydrated Metals were analyzed in oyster tissue with the method proposed by the International Atomic Enery Agency IAEA 1984 in water with Environmental Protec tion Agency EPA methodology 1984 and in sediments according to Agemian amp Chau 1976 modified by Malo 1977 and P ez Osuna 1993 The analytical procedure was corroborated with reference material IAEA 407 and GBW 08301 Known standards were used to build the pattern curve of each metal analyzed in an atomic absorption spectropho tometer Shimadzu Mod AA 6800 using hollow cathode lamps Biometrics which consisted of deter mining the length of the organisms and their fresh weight were determined individu ally and the condition index was calculated Mann 1978 Hetzel amp Wright 1983 Lucas amp Ben
15. no 1997 Hydrocarbon concentrations in oysters Crassostrea virginica and recent sediments from three coastal lagoons in Tabasco Mexico Bull Environ Contam Toxicol 59 430 437 Greig R A amp D R Wenzloff 1978 Metal accumulation and depuration by American oyster Crassostrea vir ginica Bull Environ Contam Toxicol 20 499 504 Guzman Garcia X 2001 Toxicocin tica de cadmio y da o histopatol gico en osti n Crassostrea virginica en condiciones de ayuno y alimentaci n Universidad Aut noma Metropolitana Mexico Hetzel E W amp D A Wright 1983 The use of RNA DNA ratios as an indicator of nutritional stress in the american oyster Crassostrea virginica Estuaries 6 259 259 Howard D amp C Smith 1983 Histological techniques for marine bivalve mollusks NOAA Technical Memo randum NMFS F NEC 25 NOOA Woods Hole Massachusetts USA IAEA UNEP FAO IOC 1984 Determination of total cad mium zinc lead and copper in selected marine organisms by flameless atomic absorption spectro photometry International Atomic Energy Agency Krishnakumar P K E Casillas amp U Varanasi 1994 Effect of environmental contaminants on the health of Mytilus edulis from Puget Sound Washington USA 1 Cytochemical measures of lysosomal responses in the digestive cells using automatic image analysis Mar Ecol Prog Ser 106 249 261 Long E R D D Macdonald S L Smith amp F D Calder 1995 Incidence of
16. o detoxification infiltration of hemocytes was from moderate to high in the periphery of the tubules towards the connective tissue hemocytic response was higher in organisms in the detoxification stage 20 with respect to natural oysters 10 Cd was not eliminated during depuration time 5 ugg DISCUSSION The results of heavy metals concentrations found were similar to those obtained by other authors Villanueva amp Botello 1998 Botello et al 2001 Sobrino Figueroa et al 2007 how ever other studies have reported an inverse correlation Gold Bouchot et al 1997 These findings suggest that metal levels in the lagoon sediment represent a potential pollution source for the benthic organisms The oyster biometrical parameters and the lagoon salinity had no statistical differ ences between samplings Weight and condi tion index were allometrically acceptable so all organisms in all experiments were in the best conditions Fig 4 Histopathological sections of the oyster Crassostrea virginica from the Mandinga lagoon Veracruz Mexico a Tubules of the digestive gland with edema e epithelia E and presence of hemocytes H b Connective tissue showing brown vesicles BV c Transversal section of a gonad showing peripheral increase of hemocytes d Infiltration of hemo cytes in connective tissues Hematoxylin eosin stain 960 Rev Biol Trop Int J Trop Biol ISSN 0034 7744 Vol 57 4 955 962 Decemb
17. s are useful tools that allow the visu alization of a complete map of environmental conditions REFERENCES Agemian H amp A S Y Chau 1976 Evaluation of extrac tion techniques for determination of metals in aquatic sediments Analyst 101 761 767 Borgmann U amp W P Norwood 2002 Metal bioavailabi lity and toxicity through a sediment core Environ Pollut 116 159 168 Botello A V B L Calva amp V G Ponce 2001 Polycyclic aromatic hydrocarbons in sediments from coastal lagoons of Veracruz State Gulf of Mexico Bull Environ Contam Toxicol 67 889 897 Castrejon O L D D Porras amp C S Band 1994 Cultivo de alimento vivo para la acuicultura Universidad del Mar Oaxaca Mexico Chavin W 1973 Teleostean endocrine and paraendocrine alterations of utility in environmental studies p 199 238 In W Chavin ed Responses of fishes to environ mental change Thomas Springfield Chicago USA Engel D W 1999 Accumulation and cytosolic partitioning of metals in the American oyster Crassostrea virgini ca Mar Environ Res 47 89 102 EPA Environmental Protection Agency 1984 Ambient water quality criteria for cadmium Washington D C USA Rev Biol Trop Int J Trop Biol ISSN 0034 7744 Vol 57 4 955 962 December 2009 961 Everitt B S 1992 The analysis of contingency tables Chapman amp Hall London UK Gold Bouchot G M Zavala Coral O Zapata Perez amp V Ceja More
18. vs environmental parameters and pollutant concentrations is presented in Table 3 A high correlation was observed between Cd and Cr levels in the sediment and those detected in the oyster 0 64 and 0 80 a 0 65 While a mod erately negative correlation resulted between Cd and Pb in water and those metals in the oyster 0 45 and 0 34 a 0 65 Metal con centrations in tissues also depicted statistically significant correlations from moderate to high related to the length condition index salinity pH oxygen and temperature Table 3 Salinity was correlated with Pb and Cr concentrations in the oyster r 0 60 Length and condition index correlated positively with Cd r 0 62 and 0 56 respectively The condition index also correlated well with Pb concentrations in the oyster r 0 64 20 18 Metal in oyster ugeg March 03 June 03 October 03 TABLE 3 Correlation coefficients between biometric and environmental variables and metal concentrations in C virginica from Mandinga Lagoon Veracruz Mexico Metals in oyster Cadmium Lead Chromium Length 0 62 0 39 0 20 Weight 0 04 0 19 _ 0 32 Condition Index 0 56 0 64 0 01 Salinity 0 34 0 60 0 60 pH 0 23 0 11 0 68 Oxygen 0 21 0 21 0 79 Temperature 0 84 0 71 0 58 Metals in water 0 45 0 34 0 08 Metals in sediment 0 64 0 18 0 80 Statistical significance Histology Histological analysis of indig enous organisms revea
Download Pdf Manuals
Related Search