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Archives of Environmental Contamination and Toxicology (v.41, #1)
Heavy Metal Contents in Some Macrofungi Collected in the Northwestern Part of Turkey by M. Işiloğlu; M. Merdivan; F. Yilmaz (pp. 1-7).
Eight metal contents were determined in wild growing macrofungi collected from two different areas in Balikesir and Akhisar (NW Turkey). The analysis has been done by atomic absorption spectrophotometry in 179 samples of 16 species. Pb was accumulated extensively by G. sessile and L. cinerascens in both areas. Concentration of Cd was significantly high in A. pseudopratensis from background area and M. excissa from near road area. The high concentrations of Fe and Zn were found in M. ramealis and L. cinerascens for both areas. The mean concentration of Cu was high in V. pratense from background area and C. butyracea var. butyracea from near road area. The highest mean concentrations of Co and Mn for both areas were seen in G. sessile and M. excissa, respectively. A high Ni concentration was found in G. sessile and H. hypothejus from background area. We found no considerably significant differences in the concentrations of all studied elements between two areas.
Predictions of Sediment Toxicity Using Consensus-Based Freshwater Sediment Quality Guidelines by C. G. Ingersoll; D. D. MacDonald; N. Wang; J. L. Crane; L. J. Field; P. S. Haverland; N. E. Kemble; R. A. Lindskoog; C. Severn; D. E. Smorong (pp. 8-21).
The objectives of this study were to compare approaches for evaluating the combined effects of chemical mixtures on the toxicity in field-collected sediments and to evaluate the ability of consensus-based probable effect concentrations (PECs) to predict toxicity in a freshwater database on both a national and regional geographic basis. A database was developed from 92 published reports, which included a total of 1,657 samples with high-quality matching sediment toxicity and chemistry data from across North America. The database was comprised primarily of 10- to 14-day or 28- to 42-day toxicity tests with the amphipod Hyalella azteca (designated as the HA10 or HA28 tests) and 10- to 14-day toxicity tests with the midges Chironomus tentans or C. riparius (designated as the CS10 test). Mean PEC quotients were calculated to provide an overall measure of chemical contamination and to support an evaluation of the combined effects of multiple contaminants in sediments. There was an overall increase in the incidence of toxicity with an increase in the mean quotients in all three tests. A consistent increase in the toxicity in all three tests occurred at a mean quotient > 0.5, however, the overall incidence of toxicity was greater in the HA28 test compared to the short-term tests. The longer-term tests, in which survival and growth are measured, tend to be more sensitive than the shorter-term tests, with acute to chronic ratios on the order of six indicated for H. azteca. Different patterns were observed among the various procedures used to calculate mean quotients. For example, in the HA28 test, a relatively abrupt increase in toxicity was associated with elevated polychlorinated biphenyls (PCBs) alone or with elevated polycyclic aromatic hydrocarbons (PAHs) alone, compared to the pattern of a gradual increase in toxicity observed with quotients calculated using a combination of metals, PAHs, and PCBs. These analyses indicate that the different patterns in toxicity may be the result of unique chemical signals associated with individual contaminants in samples. Though mean quotients can be used to classify samples as toxic or nontoxic, individual quotients might be useful in helping identify substances that may be causing or substantially contributing to the observed toxicity. An increase in the incidence of toxicity was observed with increasing mean quotients within most of the regions, basins, and areas in North America for all three toxicity tests. The results of these analyses indicate that the consensus-based PECs can be used to reliably predict toxicity of sediments on both a regional and national basis.
Induction of Marine Mollusc Stress Proteins by Chemical or Physical Stress by M. J. Snyder; E. Girvetz; E. P. Mulder (pp. 22-29).
The cellular stress responses of most organisms in part involve the induction of a class of proteins called heat shock or stress proteins (HSPs) as a result of damage to existing proteins. Cellular proteins can be damaged by chemical exposures known to induce various HSPs. In these experiments, we examine the HSP responses of mussel (Mytilus galloprovincialis) and abalone (Haliotis rufescens) tissues to both thermal and chemical exposures. HSP70 isoforms, HSP60, and HSP90 all show varying induction capabilities. The results demonstrate that the extent of stress exposure as both a time- and dose-dependent phenomena can be ascertained by examining changes in mollusc HSP protein levels. We also examined the relationship between HSP induction and levels of a mussel cytochrome P450 (CYP4Y1) mRNA in dose-response experiments with the products of biologically degraded weathered crude oil. The increases in HSP70 isoforms and HSP90 were correlated with decreases in CYP4Y1 expression levels in a dose-dependent manner. HSP responses may therefore be a valuable part of a suite of biomarkers in biomonitoring for hydrocarbon exposures in nearshore environments.
The Geographic Distribution of Population Health and Contaminant Body Burden in Gulf of Mexico Oysters by Y. Kim; E. N. Powell; T. L. Wade; B. J. Presley; J. M. Brooks (pp. 30-46).
As part of NOAA's National Status and Trends Mussel Watch Program, oysters were sampled along the Gulf of Mexico coast each winter from 1986 to 1993 (The present analysis deals with 1986–1993 Mussel Watch data; the Mussel Watch project itself continues at this printing) and analyzed for trace metal, polynuclear aromatic hydrocarbons and pesticide body burden, plus a series of biological variables designed to assess population status and health. We identified contaminant and biological variables in which large-scale spatial processes played an important role in establishing population values by examining the likelihood that neighboring bays tended to have populations with body burdens or population attributes more similar than expected by chance.Local or watershed-dependent factors, such as land use and freshwater inflow, are important in controlling the bay-to-bay variation in body burden in most contaminants. However, the bay-to-bay variations in body burden of some metals (As, Cd, Hg, Ni, Se) appear to be principally influenced by larger-scale climatic factors. These metals and the biological variable shell length demonstrated a strong degree of similarity between bays over a large regional area reminiscent of the pattern shown by climatic factors, such as temperature and precipitation. In contrast, among the organics, none of the PAHs showed even a moderately strong climatic signal. Among the pesticides, only two did (dieldrin, total DDTs). These pesticides and the biological variables, reproductive stage and Perkinsus marinus prevalence and infection intensity, had spatial patterns that suggested both a local and a regional influence to their geographic distributions. This same pattern is exhibited by freshwater runoff. Metal contaminants also behaved distinctively compared to organics in the temporal influence of climate in establishing the interannual variability in body burden. For the organics, trends in interannual variability were strongly influenced by climate, whereas spatial trends were not. In contrast, most metals were unaffected by climatic forcing both spatially and temporally. However, all of the metals having a spatial pattern strongly influenced by climate (As, Cd, Hg, Ni, Se) also exhibited interannual variations related to variations in climate.
Effects of Methylmercury on Ontogeny of Prey Capture Ability and Growth in Three Populations of Larval Fundulus heteroclitus by T. Zhou; R. Scali; J. S. Weis (pp. 47-54).
We used three populations of mummichogs (Fundulus heteroclitus), one from a polluted site (Piles Creek [PC], New Jersey) and two from cleaner sites (Tuckerton [TK], New Jersey, and East Hampton [EH], New York), to study (1) whether embryonic, embryonic plus larval, or larval exposure to methylmercury (MeHg) altered larval prey capture ability and growth; and (2) whether there were differences in tolerance to MeHg-induced behavioral changes among the three populations. Eggs and sperm were obtained from mummichogs captured in the field, and their embryos and larvae were kept in clean sea water or MeHg solution (5, 10 μg/L). Larvae were then tested regularly for prey capture rates and prey capture efficiencies, and their lengths were measured. Embryonic exposure to MeHg induced transitory and recoverable impairments in larval prey capture ability, whereas larval exposure alone was relatively ineffective. When both embryos and larvae were treated, larval prey capture ability was affected at a lower concentration and a wider range of larval ages. In terms of growth and prey capture ability, response of larvae to embryonic or larval or exposure to both stages to MeHg varied with populations. TK fish were the most tolerant with respect to behavioral changes but were the most sensitive to MeHg in reduction of growth. EH fish were the most sensitive whenever embryos were treated, and PC fish were the most vulnerable after larval exposure. The population differences in response to MeHg intoxication may be due to pollution related factors or differences in behavioral-related genetic factors.
Effects of Acute Handling Stress on Whitefish Coregonus lavaretus After Prolonged Exposure to Biologically Treated and Untreated Bleached Kraft Mill Effluent by J. Lappivaara (pp. 55-64).
Exposure of fish to water of impaired quality has been shown to disrupt the function of the hypothalamo-pituitary-interrenal (HPI) axis and alter the interpretation of data from field studies due to the varying effects of handling and delayed sampling on exposed and reference animals. In the present study, juvenile whitefish, Coregonus lavaretus, were exposed for 6 weeks to diluted (4–8%) untreated and biologically treated bleached kraft mill effluent (BKME) and their response to acute handling was investigated. Liver microsomal EROD activity and glycogen phosphorylase (GPase) activity, in addition to gill Na+-K+-ATPase activity, and blood hemoglobin and hematocrit levels were increased in whitefish exposed for 6 weeks to untreated BKME, whereas those exposed to treated BKME exhibited increased blood hemoglobin and red blood cell K+ concentrations. Both handling procedures, exposure to a shallow water (10 cm, 5 min) and to an air challenge (10 s air/10 s water/30 s air/10 s water/10 s air), resulted in acute physiological stress, as recorded after 5-, 60-, and 120-min recovery periods. Following air exposure, the levels of plasma cortisol, blood glucose, hemoglobin, and hematocrit as well as the liver GPase activity were increased, and liver glycogen concentration decreased in control fish. These responses were attenuated in fish exposed to untreated or treated BKME. Plasma estradiol and testosterone levels were not affected by the BKME exposures or by the air challenge. Handling also resulted in attenuated EROD induction in fish exposed to untreated BKME. According to the present findings, the sensitivity of some widely used cellular and physiological variables may be improved by time-dependent standardization when interpreting data obtained following delayed sampling.
Porphyrin Levels in Excreta of Sea Birds of the Chilean Coasts as Nondestructive Biomarker of Exposure to Environmental Pollutants by S. Casini; M. C. Fossi; J. F. Gavilan; R. Barra; O. Parra; C. Leonzio; S. Focardi (pp. 65-72).
In this preliminary study on sea birds we propose the use of porphyrins in excreta as a biomarker of exposure to contaminants. Samples of excreta were obtained from colonies of brown pelicans (Pelecanus occidentalis thagus), neotropic cormorants (Phalacrocorax olivaceus), and kelp gulls (Larus dominicanus) in three areas of the south coast of Chile with different human impact (Tubul, Talcahuano, and Valdivia). They were analyzed for porphyrin content (copro-, uro-, and protoporphyrins and total porphyrins) by a rapid fluorimetric method and by HPLC. The main outcomes of the study were: (a) kelp gulls and neotropic cormorants living in areas with high human impact showed a clear capacity to accumulate and eliminate porphyrins in the excreta; (b) species-related accumulation capacities are likely, as shown by the different levels found in different species living in the same area; (c) the porphyrin profile obtained by fluorimetry and HPLC showed a higher percentage of protoporphyrin than the other porphyrins; (d) although the fluorimetric method of Grandchamp is semiquantitative, it was found to be sensitive enough to detect differences in samples from field studies. The positive results of this preliminary study make it possible to propose this nondestructive method for a variety of field applications.
Organochlorine Contaminant Exposure and Reproductive Success of Black-Crowned Night-Herons (Nycticorax nycticorax) Nesting inBaltimore Harbor, Maryland by B. A. Rattner; P. C. McGowan; J. S. Hatfield; C.-S. Hong; S. G. Chu (pp. 73-82).
The declining size of the Baltimore Harbor black-crowned night-heron (Nycticorax nycticorax) colony has been hypothesized to be linked to polychlorinated biphenyl (PCB) exposure. In 1998, a “sample egg” was collected from 65 black-crowned night-heron nests (each containing ≥ three eggs) for contaminant analysis, and the remaining eggs in these 65 nests, plus four two-egg nests, were monitored for hatching and fledging success. Eggs were also collected from 12 nests at Holland Island, a reference site in southern Chesapeake Bay. Samples were analyzed for 26 organochlorine pesticides and metabolities and 145 PCB congeners. Pesticide and metabolite concentrations, including p,p'-DDE, were well below thresholds associated with adverse reproductive effects at both sites. Average concentration of total PCBs, 12 Ah receptor–active PCB congeners, and toxic equivalents in eggs from Baltimore Harbor were greater (up to 35-fold) than that observed in Holland Island samples. Overall nest success at the Baltimore Harbor heronry was estimated by the Mayfield method to be 0.74, and the mean number of young fledged/hen was 2.05, which is within published productivity estimates for maintaining a stable black-crowned night-heron population. Using logistic regression, no significant relationships were found between organochlorine contaminant concentrations in sample eggs and hatching, fledging, or overall reproductive success. Processes other than poor reproduction (e.g., low postfledging survival, emigration, habitat degradation) may be responsible for the declining size of the Baltimore Harbor colony.
Protection of Sodium Arsenite-Induced Ovarian Toxicity by Coadministration of L-Ascorbate (Vitamin C) in Mature Wistar Strain Rat by S. Chattopadhyay; S. Ghosh; J. Debnath; D. Ghosh (pp. 83-89).
Arsenic, a major water pollutant in India, produces toxic effects on female reproductive system in rodent models at the dose available in drinking water in arsenic-intoxicated zones. This study examines the coadministration of L-ascorbate (vitamin C) on ovarian steroidogenesis, plasma levels of gonadotrophins, brain monoamines, and ovarian as well as uterine peroxidase activities in sodium arsenite–treated rats. After sodium arsenite treatment, relative ovarian and uterine weights, ovarian Δ5-3β-HSD and 17β-HSD activities, plasma levels of gonadotrophins, norepinephrine levels in midbrain and diencephalon, and the activities of peroxidase in ovary and uterus were decreased significantly. On the other hand, serotonin levels in midbrain and diencephalon were increased significantly 28 days after sodium arsenite treatment at the dose of 0.4 ppm/100 g body weight/rat/day. All these parameters were protected significantly and in most cases were unchanged from control level when L-ascorbate at 25 mg/100 g body weight/rat/day was coadministered orally with sodium arsenite. This cotreatment of L-ascorbate with sodium arsenite also restored the estrous cycle in a regular manner. We concluded that L-ascorbate plays a pivotal role in maintaining normal ovarian activities and brain monoamines in arsenic-treated rats.
Organochlorine Pesticides, Polychlorinated Biphenyls, and Butyltin Compounds in Blubber and Livers of Stranded California Sea Lions, Elephant Seals, and Harbor Seals from Coastal California, USA by N. Kajiwara; K. Kannan; M. Muraoka; M. Watanabe; S. Takahashi; F. Gulland; H. Olsen; A. L. Blankenship; P. D. Jones; S. Tanabe; J. P. Giesy (pp. 90-99).
Concentrations of polychlorinated biphenyls (PCBs), DDTs (p,p′-DDE, p,p′-DDD, p,p′-DDT), chlordanes (CHLs; cis-chlordane, cis-nonachlor, trans-nonachlor, and oxychlordane), hexachlorocyclohexane isomers (HCHs), hexachlorobenzene (HCB), tris(4-chlorophenyl)methane (TCPMe), tris(4-chlorophenyl)methanol (TCPMOH), and mono- (MBT), di-(DBT), and tri-butyltin (TBT) were determined in blubber and livers of 15 California sea lions (Zalophus californianus), 6 northern elephant seals (Mirounga augustirostris), and 10 harbor seals (Phoca vitulina) found stranded along the coasts of California, USA, during 1991–1997. Among the organochlorines analyzed, DDTs were predominant, followed in decreasing order by PCBs, CHLs, TCPMe, TCPMOH, HCHs, and HCB. The greatest concentrations of organochlorines were found in California sea lions. The highest DDT and PCB concentrations found in the blubber of California sea lions were 2,900 and 1,300 μg/g, lipid weight, respectively. Concentrations of TCPMe and TCPMOH in California sea lions were correlated significantly with DDT concentrations. Concentration ratios of various organochlorines in harbor seal livers were different from those in California sea lions and elephant seals, which suggested that the sources of exposure of harbor seals to organochlorines were different from those in the other two species. Concentrations of butyltin compounds in livers of pinniped species ranged from 2 to 99 ng/g, wet weight, which were less than those observed in cetaceans and in California sea otters.
Cadmium Accumulation and Distribution in Slaughtered Horse Kidneys from the Argentine Central Region by H. R. Beldoménico; E. Baroni; D. U. Campagnoli; M. E. Sigrist; M. Rubio; J. C. Boggio (pp. 100-103).
In this paper we report the results of surveys conducted in Argentina between 1997 and 1998 to know the Cd concentrations in kidney from horses of different age, sex, and origin. Cd in renal cortex and medulla was positively correlated, and higher concentrations in the cortex were found. No significant differences between values from left and right kidneys of the same animal were found. An increase in Cd levels with age of animals were observed, and no sex incidence was verified in renal Cd composition. No detectable residues were found in the fetuses tested. Levels observed in Argentine equines (n = 102) ranged from 4.3 to 83.8 μg Cd/g in kidney cortex, lower than those reported by other authors but higher than the action levels proposed by Argentine meat tissue species regulations. Therefore, the study remarks on the convenience of monitoring Cd in Argentine equines and gives relevant information for regulatory purposes to consider the limitation in the use of horse kidney as food for either human or animals.
Evaluation of Immune Parameters in Propanil-Exposed Farm Families by G. Y. H. McClure; R. M. Helm; K. Stine; A. W. Burks; S. M. Jones; J. Gandy (pp. 104-111).
The rice herbicide propanil induces alterations in the mouse immune system, causing significant decreases in T cell–dependent and T cell–independent antibody responses. This postemergent herbicide is used extensively in rice production in the Mississippi River delta region of the southern United States. The aerial application and airborne drift of propanil may pose health concerns to exposed farm families living adjacent to sprayed rice fields. To determine if aerial spraying of propanil increases risks of altered immune responses in families bordering rice fields, immune parameters were assessed during a 2-year study. Families living within 100 yards of rice fields were compared in a case control study to farm families whose homes exceeded 1 mile from any rice field. Blood was analyzed in adults (n = 56) and children (n = 52) at three time intervals: (1) preseason, prior to propanil application; (2) 5–7 days after aerial application of propanil to rice fields; and (3) postseason, following harvest. Exposed adults and children were compared with controls for a number of immune parameters. Total cell count and the percentage of various lymphocytes (T cells, B cells, CD4+ helper cells, and CD8+ suppressor cells) and natural killer (NK) cells, mitogen-induced cell proliferation, cytokine (IL-2+) production, and NK cell function were assessed. A comparison of immune function between exposed and nonexposed farm families showed no significant differences, possibly related to propanil exposure. However, some immune test parameters changed as a function of season rather than propanil exposure. The data indicate that individuals living next to rice fields are not at increased risk of altered immune function due to propanil exposure.
Propanil (3,4-Dichloropropionanilide) Particulate Concentrations Within and Near the Residences of Families Living Adjacent to Aerially Sprayed Rice Fields by S. M. Richards; G. Y. H. McClure; T. L. Lavy; J. D. Mattice; R. J. Keller; J. Gandy (pp. 112-116).
Propanil is widely used as a postemergence herbicide in rice. Because it is typically applied aerially, there is a potential for propanil to drift into and around homes of those living adjacent to rice fields. Propanil has been shown to be immunotoxic in rodent models. The objective of this study was to measure the levels of propanil to which families living adjacent to aerially sprayed rice fields may be exposed.Air levels were sampled by actively and passively collecting propanil in and around the homes of volunteer families living in close proximity to rice fields sprayed with propanil. Homes ranged from 73 m to 113 m from treated rice fields. Sampling was conducted in the home, adjacent to the home (within 5 m of the home), 30 m from the home, and at the edge of the rice field. Concentrations were determined via gas chromatography/mass spectroscopy.Propanil levels adjacent to the homes ranged from nondetectable to 1,106.4 μg per 400 cm2 collection surface (2.0 μg detection limit). Wind direction and wind velocity were the primary determinants of propanil drift. At sites where the prevailing wind was blowing away from the home, no propanil was detected except at the edge of the field. Distance from the edge of the rice field also influenced the amount of drift with higher levels measured at 30 m from the house than adjacent to the house. No propanil vapor was detected on absorbent media sampled in and around the homes.The results indicate that individuals living adjacent to rice fields aerially sprayed with propanil are potentially exposed to variable amounts of propanil, and wind speed and direction are the most important factors that influence the concentration of aerially applied pesticide.