Essential and non-essential trace metals in scalp hair of men chronically exposed to volcanogenic metals in the Azores, Portugal

Volcanoes produce and release large amounts of toxicants, and the concentration of metals in hair can be used as a biomarker of exposure to trace metals. In order to investigate whether humans exposed to volcanic emissions demonstrate higher concentrations of essential and non-essential trace metals, scalp hair of men (3-89 years) living in two areas of the Azores, one exposed to volcanic emissions and the other not, was sampled, and their content in Cd, Cu, Pb, Rb, Se, and Zn was quantified by using High Resolution Inductively Coupled Plasma Mass Spectrometry. In average, men exposed to volcanic emissions presented higher concentrations of Cd (96.9 ppb), Cu (16.2 ppm), Pb (3417.6 ppb), Rb (216.3 ppb), and Zn (242.8 ppm), but not Se (469.6 ppb). Also, strong and significant correlations were found between Cd-Rb and Pb-Rb in the exposed men. In conclusion, humans living chronically exposed to volcanic emissions show high concentrations of essential and non-essential trace metals in scalp hair, and is suggested that this type of exposure may be as harmful as living close to industrial facilities.     

Effects of feeding time and organic loading in an anaerobic sequencing batch biofilm reactor (ASBBR) treating diluted whey

An investigation was carried out on the performance of an anaerobic sequencing batch biofilm reactor (ASBBR) treating diluted cheese whey when submitted to different feed strategies and volumetric organic loads (VOL). Polyurethane foam cubes were used as support for biomass immobilization and stirring was provided by helix impellers. The reactor with a working volume of 3 L treated 2 L of wastewater in 8-h cycles at 500 rpm and 30 degrees C. The organic loads applied were 2, 4, 8 and 12 g COD L(-1) d(-1), obtained by increasing the feed concentration. Alkalinity was supplemented at a ratio of 50% NaHCO(3)/COD. For each organic load applied three feed strategies were tested: (a) batch operation with 8-h cycle; (b) 2-h fed-batch operation followed by 6-h batch; and (c) 4-h fed-batch followed by 4-h batch. The 2-h fed-batch operation followed by 6-h batch presented the best results for the organic loads of 2 and 4 g COD L(-1) d(-1), whereas the 4-h fed-batch operation followed by 4-h batch presented results slightly inferior for the same organic loads and the best results at organic loads of 8 and 12 g COD L(-1) d(-1). The concentration of total volatile acids varied with fill time. For the higher fill times maximum concentrations were obtained at the end of the cycle. Moreover, no significant difference was detected in the maximum concentration of total volatile acids for any of the investigated conditions. However, the maximum values of propionic acid tended to decrease with increasing fill time considering the same organic load. Microbiological analyses revealed the presence of Methanosaeta-like structures and methanogenic hydrogenotrophic-like fluorescent bacilli. No Methanosarcina-like structures were observed in the samples.     

Identification and chemical characterization of industrial particulate matter sources in southwest Spain

A detailed physical and chemical characterization of coarse particulate matter (PM10) and fine particulate matter (PM2.5) in the city of Huelva (in Southwestern Spain) was carried out during 2001 and 2002. To identify the major emission sources with a significant influence on PM10 and PM2.5, a methodology was developed based on the combination of: (1) real-time measurements of levels of PM10, PM2.5, and very fine particulate matter (PM1); (2) chemical characterization and source apportionment analysis of PM10 and PM2.5; and (3) intensive measurements in field campaigns to characterize the emission plumes of several point sources. Annual means of 37, 19, and 16 microg/m3 were obtained for the study period for PM10, PM2.5, and PM1, respectively. High PM episodes, characterized by a very fine grain size distribution, are frequently detected in Huelva mainly in the winter as the result of the impact of the industrial emission plumes on the city. Chemical analysis showed that PM at Huelva is characterized by high PO4(3-) and As levels, as expected from the industrial activities. Source apportionment analyses identified a crustal source (36% of PM10 and 31% of PM2.5); a traffic-related source (33% of PM10 and 29% of PM2.5), and a marine aerosol contribution (only in PM10, 4%). In addition, two industrial emission sources were identified in PM10 and PM2.5: (1) a petrochemical source, 13% in PM10 and 8% in PM2.5; and (2) a mixed metallurgical-phosphate source, which accounts for 11-12% of PM10 and PM2.5. In PM2.5 a secondary source has been also identified, which contributed to 17% of the mass. A complete characterization of industrial emission plumes during their impact on the ground allowed for the identification of tracer species for specific point sources, such as petrochemical, metallurgic, and fertilizer and phosphate production industries.     

Antimicrobial susceptibility of Escherichia coli isolated from shrimp (Litopenaeus vannamei) and pond environment in northeastern Brazil

This study aimed to test the susceptibility of Escherichia coli strains isolated from the water, bottom sediments and individuals cultivated in shrimp farm ponds, to antibiotics belonging to different families, namely B-Lactams: Imipenem (IPM; 10 μ g), Ampicillin (AMP; 10 μ g), Cephalothin (CEP; 30 μ g), Cefoxitin (FOX; 30 μ g), Ceftriaxone (CRO; 30 μ g); Tetracycline: Tetracycline (TCY; 30 μ g); Aminoglycosides: Gentamicin (GEN; 10 μ g), Amikacin (AMK; 30 μ g); Chloramphenicol: Chloramphenicol (CHO; 30 μ g); Fluoroquinolones: Ciprofloxacin (CIP; 5 μ g); Nitrofurans: Nitrofurantoin (NIT; 300 μ g); Sulfonamides: Trimethoprim-Sulfamethoxazole (SXT; 30 μ g); Quilononas: Nalidixic Acid (NAL; 30 μ g). In the laboratory, the method of dissemination (Test Kirby-Bauer) was performed in order to fulfill the antibiogram tests. The results showed high indices of resistance to Imipenem, Cephalothin and Ampicillin. Chloramphenicol, Nitrofurantoin, Cefoxitin, Ceftiaxone and Ciprofloxacin have displayed the highest index of sensitive strains. The antibiotic resistance index (ARI) and the multiple resistance index (MAR) varied within the ranges of 0.068–0.077 and 0.15–0.39, respectively. More than 90.5% of strains of Escherichia coli showed a variety of resistance profiles to the tested antibiotics. The high indices of resistance may be a consequence of indiscriminate use of antibiotics, but also the transfer of resistance through mobile genetic elements found in shrimp farms.     

Inorganic chemical composition of native trees of the Atlantic Forest

The Atlantic Forest with its exuberant vegetation of high level of biodiversity is classified as one hotspot of the world. Chemical composition of leaves from native trees and underlying soils was evaluated by INAA. The predominant species Euterpe edulis, Bathysa meridionalis, Hyeronima alchorneoides, Marlierea tomentosa, Gomidesia flagellaris, and Gomidesia spectabilis belonging to the diverse plant families were studied. Euterpe edulis, the most abundant understory specie, presented the lowest element concentrations except for Zn. Some variation in chemical composition was noted, however, the chemical specificity of tree species can be more predominant than the soil variability for the obtained leaf concentrations. Factor values obtained through the Monte-Carlo assisted factor analysis were used for species discrimination. The results indicate that chemical investigation of native trees is a quite promising tool for biodiversity studies in the Atlantic Forest.     

Teratological effects of pesticides in vertebrates: a review

Abstract

In the last decades, the use and misuse of pesticides in the agriculture have increased, having a severe impact on ecosystems and their fauna. Although the various effects of pesticides on biodiversity have been already documented in several studies, to our knowledge no consistent overview of the impact of pesticides in vertebrates, both terrestrial and aquatic, is available. In this review, we try to present a concise compilation of the teratogenic effects of pesticides on the different classes of vertebrates – mammals, birds, reptiles, amphibians and fish.     

Measurements of carbonyls in a 13-story building

BACKGROUND, AIM AND SCOPE: Formaldehyde and acetaldehyde are emitted by many mobile and stationary sources and secondary aldehydes are intermediates in the photo-oxidation of organic compounds in the atmosphere. These aldehydes are emitted indoors by many materials such as furniture, carpets, heating and cooling systems, an by smoking. Carbonyls, mainly formaldehyde and acetaldehyde, have been studied because of their adverse health effects. In addition, formaldehyde is a suspected carcinogen. Therefore, the concentrations of formaldehyde and acetaldehyde were determined to assess the inhalation exposure doses to carbonyls for people who work in a 13-story building and in order to evaluate the cancer hazard. METHODS: Carbonyl compounds in indoor and outdoor air were measured at a 13-story building located in Mexico City. The mezzanine, fifth and tenth floors, and the third level-parking garage were selected for sampling. Samples were collected in two sampling periods, the first from April 20 to 29, 1998 and the second from December 1 to 20, 1998. Carbonyls were sampled by means of DNHP-coated cartridges at a flow rate of 1 l min(-1) from 9:00 to 19:00 hours, during 2-hour time intervals and analyzed by HPLC with hours, during 2-hour time intervals and analyzed by HPLC with UV/VIS detection. RESULTS: Mean carbonyl concentrations were highest in the 3rd level-parking garage, with the formaldehyde concentration being the highest ranging from 108 to 418 microg m(-3). In working areas, the highest carbonyl arithmetic mean concentrations (AM) were observed on the 5th floor. Acetone and formaldehyde concentrations were highest in April ranging from 161 to 348 microg m(-3) (AM = 226) and from 157 to 270 microg m(-3) (AM = 221), respectively. Propionaldehyde and butyraldehyde were present in smaller concentrations ranging from 2 to 25 and 1 to 28 microg m(-3), respectively, considering all the samples. Mean indoor/outdoor ratios of carbonyls ranged from 1.8 to 9.6. A reduction of inhalation exposure doses of 41% and 45% was observed in the fifth floor air after the air conditioning systems had been repaired. Formaldehyde and acetaldehyde concentrations were higher in smoking environments. CONCLUSION: Indoor carbonyl concentrations were significantly greater than outdoor concentrations. Tobacco smoke seems to be the main indoor source of formaldehyde. After the air conditioning system was maintained and repaired (as was recommended), an important reduction in the emission of formaldehyde and acetaldehyde was achieved on all floors, except for the 3rd level parking garage, thereby reducing the inhalation exposure doses. RECOMMENDATION: The results obtained in this research demonstrated that maintenance of air conditioning systems must be carried out regularly in order to avoid possible adverse effects on health. Additionally, it is mandatory that isolated smoking areas, with air extraction systems, be installed in every public building.     

IMPACTS OF URBANIZATION ON NUTRIENT CONCENTRATIONS IN SMALL SOUTHEASTERN COASTAL STREAMS1

ABSTRACT: Coastal watersheds in the southeastern United States are rapidly changing due to population growth and attendant increases in residential development, industry, and tourism related commerce. This research examined spatial and temporal patterns of nutrient concentrations in streams from 10 small watersheds (< 4 km²) that drain into Murrells Inlet (impacted) and North Inlet (pristine), two high salinity estuaries along the South Carolina coast. Monthly grab samples were collected during baseflow during 1999 and analyzed for total and dissolved inorganic and organic forms of nitrogen and phosphorus. Data were grouped into forested wetland creeks (representing predevelopment reference sites), urban creeks, and urban ponds. DON and NH4 concentrations were greater in forested streams than in urban streams. NO3 and TP concentrations were greatest in urban streams. Seasonally, concentrations were highest during summer for TN, NH4, DON, and TP, while NO3 concentrations were greatest during winter. Nutrient ratios clearly highlighted the reduction in organic nitrogen due to coastal development. Multiple regression models to predict instream nutrient concentrations from land use in Murrells Inlet suggest that effects are not significant (small r²). The findings indicate that broad land use/land cover classes cannot be used to predict nutrient concentrations in streams in the very small watersheds in our study areas.     

Lipids and stable carbon isotopes in two species of Hawaiian corals,<Emphasis Type="Italic"> Porites compressa</Emphasis> and<Emphasis Type="Italic"> Montipora verrucosa</Emphasis>, following a bleaching event

Mass coral bleaching events have occurred on a global scale throughout the worlds tropical oceans and can result in large-scale coral mortality and degradation of coral reef communities. Coral bleaching has often been attributed to periods of above normal seawater temperatures and/or calm conditions with high levels of ultraviolet radiation. Unusually high shallow-water temperature (>29°C) in Kaneohe Bay, Hawaii, USA, in late summer (20 August–9 September) and fall (1–7 October) of 1996 produced visible bleaching of two dominant corals, Porites compressa Dana, 1864 and Montipora verrucosa Dana, 1864. The present study examined chlorophyll a (chl a), total lipid concentrations, and lipid class composition in corals of both species in which the entire colony was non-bleached, moderately bleached, or bleached. Skeletal, host tissue, and algal symbiont ¹³C values were also measured in non-bleached and bleached colonies. In additional unevenly bleached colonies, paired samples were collected from bleached upper surfaces and non-bleached sides. Samples were collected on 20 November 1996 during the coral recovery phase, a time when seawater temperatures had been back to normal for over a month. Chl a levels were significantly lower in bleached colonies of both species compared with non-bleached specimens, and in bleached areas of unevenly bleached single colonies. Total lipid concentrations were significantly lower in bleached P. compressa compared with non-bleached colonies, whereas total lipid concentrations were the same in bleached and non-bleached M. verrucosa colonies. The proportion of triacylglycerols and wax esters was lower in bleached colonies of both species. Both bleached and non-bleached M. verrucosa had from ~17% to 35% of their lipids in the form of diacylglycerol, while this class was absent in P. compressa. ¹³C was not significantly different in the host tissue and algal symbiont fractions in non-bleached and bleached samples of either species. This suggests that the ratio of carbon acquired heterotrophically versus photosynthetically was the same regardless of condition. Skeletal ¹³C was significantly lower in bleached than in non-bleached corals. This is consistent with previous findings that lower rates of photosynthesis during bleaching results in lower skeletal ¹³C values. The two species in this study displayed different lipid class compositions and total lipid depletions following bleaching, suggesting that there is a difference in their metabolism of lipid reserves and/or in their temporal responses to bleaching and recovery.Communicated by J.P. Grassle, New Brunswick