SciCombinator

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Journal: Archives of environmental contamination and toxicology

79

Benzophenone-3 (BP-3; oxybenzone) is an ingredient in sunscreen lotions and personal-care products that protects against the damaging effects of ultraviolet light. Oxybenzone is an emerging contaminant of concern in marine environments-produced by swimmers and municipal, residential, and boat/ship wastewater discharges. We examined the effects of oxybenzone on the larval form (planula) of the coral Stylophora pistillata, as well as its toxicity in vitro to coral cells from this and six other coral species. Oxybenzone is a photo-toxicant; adverse effects are exacerbated in the light. Whether in darkness or light, oxybenzone transformed planulae from a motile state to a deformed, sessile condition. Planulae exhibited an increasing rate of coral bleaching in response to increasing concentrations of oxybenzone. Oxybenzone is a genotoxicant to corals, exhibiting a positive relationship between DNA-AP lesions and increasing oxybenzone concentrations. Oxybenzone is a skeletal endocrine disruptor; it induced ossification of the planula, encasing the entire planula in its own skeleton. The LC50 of planulae exposed to oxybenzone in the light for an 8- and 24-h exposure was 3.1 mg/L and 139 µg/L, respectively. The LC50s for oxybenzone in darkness for the same time points were 16.8 mg/L and 779 µg/L. Deformity EC20 levels (24 h) of planulae exposed to oxybenzone were 6.5 µg/L in the light and 10 µg/L in darkness. Coral cell LC50s (4 h, in the light) for 7 different coral species ranges from 8 to 340 µg/L, whereas LC20s (4 h, in the light) for the same species ranges from 0.062 to 8 µg/L. Coral reef contamination of oxybenzone in the U.S. Virgin Islands ranged from 75 µg/L to 1.4 mg/L, whereas Hawaiian sites were contaminated between 0.8 and 19.2 µg/L. Oxybenzone poses a hazard to coral reef conservation and threatens the resiliency of coral reefs to climate change.

Concepts: Algae, Ultraviolet, Coral, Coral reef, Coral bleaching, Cnidaria, Sunscreen, Coral reefs

28

Vanadium concentrations in soil can be increased through anthropogenic inputs and can be harmful to plants. A Petri dish experiment was conducted to assess the effect of vanadium toxicity on the germination and survival of the garden lettuce, Lactuca sativa. A second study was conducted in a greenhouse to investigate the influence of species selection and nutrient concentration on the toxicity of vanadium pentoxide to plants. L. sativa and four non-crop native plant species, two grasses (Elymus virginicus and Panicum virgatum) and two broad-leaved species (Lycopus americanus and Prunella vulgaris) were selected. Artificial soil was used in both experiments, and a geometric progression of five vanadium concentrations plus controls was selected for the soil treatments. Results of the Petri dish experiment showed that seedling survival is a less sensitive end point than above-ground dry weight (DW) as measured in the greenhouse experiment. Nutrient level (100, 10, and 1 kg/ha) was found to strongly influence vanadium toxicity in the greenhouse study. At 100 kg/ha, plant tolerance to vanadium was greatest, as indicated by higher no-observed, lowest-observed, and percentage effect concentration values. Results showed that forbs (L. americanus and P. vulgaris) tended to be more sensitive than both the crop (L. sativa) and grasses (E. virginicus and P. virgatum) at high concentrations of vanadium. Soil concentrations resulting in a 25 % decrease in shoot DW were generally less than the Canadian soil quality guideline for vanadium, suggesting that 130 mg/kg may not be protective of the Canadian native plant species used in this study.

Concepts: Plant, Annual plant, Lamiaceae, Lettuce, Lactuca

27

The Paranaguá Estuarine System (PES) is an important estuarine environment on the Brazilian coast. The economic importance of the PES is mainly related to industries, fuel terminals, and the main South American grain-shipping port. The aim of this work was to determine the vertical distribution of polychlorinated biphenyls (PCBs) in three sediment cores from the PES. The methods included Soxhlet extraction, clean-up, and quantification by gas chromatography with electron capture detection. The concentrations of total PCBs ranged from lower than the detection limit to 6.65 ng g(-1). Low PCB concentrations were detected in P1 and P3, which were collected far away from direct human activities. In P2, the compositional pattern of PCB congeners showed greater concentrations of tetra- and penta-chlorinated congeners associated with urban and port activities near Paranaguá city. The differences in concentrations between the three sediment cores were attributed to the distance of the sampling points in relation to the possible sources of pollution, which are mostly related to Paranaguá city. The vertical distribution of PCBs in the sediment core P2 was related to historical anthropogenic activities. The highest PCB input was from 1970 to the early 1990s, which coincides with a period of greater use of PCBs in Brazil as well as their greater worldwide production.

Concepts: Analytical chemistry, Polychlorinated biphenyl, PCB Congener List

27

Approximately 5.4 million cubic yards of coal fly ash and water spilled into the Emory River embayment of Watts Bar Reservoir in east Tennessee on Dec 22, 2008. Raccoons were collected in 2009 and 2010 from the spill site (10/y) and unexposed areas (5/y) to determine whether metals and metalloids were accumulating in raccoons and if any negative health effects resulted from exposure to the spilled coal fly ash. Tissues were analyzed from each animal to determine the concentrations of 26 metals/metalloids. Complete blood cell counts (CBC), plasma biochemistry panels, and histopathology of select tissues also were performed. Results were analyzed by year and exposure status. Although significant differences were present in some tissues for some metals/metalloids, only arsenic in hair, iron in muscle, nickel in hair, selenium in hair and muscle, strontium in hair, and vanadium in hair and liver were increased in spill site animals (one or both years) compared with unexposed animals. No clinically important differences were observed between groups regarding CBC or plasma biochemistry analyses. Lesions were observed on histopathology in some tissues, but there was no difference in the prevalence of lesions between spill site and unexposed animals. There does not seem to be any important accumulation of metals/metalloids or negative health effects in raccoons associated with exposure to coal fly ash compared with unexposed animals.

Concepts: Metal, Coal, Complete blood count, Fly ash, Pozzolana, Bottom ash, Raccoon, Kingston Fossil Plant coal fly ash slurry spill

27

In this study, we investigated whether the terrestrial moss Pseudoscleropodium purum can be used to biomonitor atmospheric deposition of nitrogen (N). For this purpose, we first determined whether there are any interspecific differences in the concentrations of total N and δ(15)N between the two species of terrestrial moss most commonly used in biomonitoring studies, P. purum and Hypnum cupressiforme. Second, we determined the spatial distribution of N and δ(15)N at small and large scales: (1) by analysis of 165 samples from the surroundings of an aluminium smelter and (2) by analysis of 149 samples from sites forming part of a regular 15 × 15-km sampling network in Galicia (northwest Spain). We did not find any interspecific differences in either total N or δ(15)N. Analysis of δ(15)N enabled us to identify large-scale spatial patterns of distribution that were congruent with the location of the main N emission sources (unlike the analysis of total N). However, we did not identify any such patterns for the small-scale source of N emission studied. The results show that analysis of δ(15)N has an advantage compared with the analysis of total N in that it provides information about the source of N rather than about the amount of N received. Furthermore, isotope discrimination appears to occur, with the bryophytes preferentially accumulating the N(14) isotope. Although this amplifies the signal of reduced forms, it is not problematical for determining spatial-distribution patterns.

Concepts: Iron, Plant, Aluminium, Source, Bryophyte, Moss, Marchantiophyta, Mosses

8

Bt crops are one of the most commonly used genetically modified crops worldwide. Bt crops contain a gene that is derived from the bacteria Bacillus thuringiensis, which produces the Cry1Ab toxin. Bt corn that contains the Cry1Ab toxin is used throughout the Midwest United States to control crop pests such as the European corn borer (Ostrinia nubilalis). Headwater streams in regions known for intensive agriculture receive Bt corn detritus after the fall harvest, which is then consumed by a diverse community of stream invertebrates. The rusty crayfish (Orconectes rusticus) is a common invertebrate detritivore in these headwater streams. Both isogenic and Bt corn were grown under the controlled environmental conditions of a greenhouse and, after senescence, were tested for nutritional equality. Rusty crayfish were exposed to one of several detrital treatments composed of Bt corn, Bt corn plus American sycamore (Platanus occidentalis), isogenic corn alone, isogenic corn plus P. occidentalis, or P. occidentalis alone for 8 weeks. Both strains of corn were grown under the controlled environmental conditions in a greenhouse and were tested for nutritional equality after senescence. Crayfish were housed in live streams with a water temperature of 12.8 °C and a 12:12 h light-to-dark photoperiod. Survival and growth of animals within each experimental treatment were monitored each week. After 8 weeks of exposure, there was no statistically significant difference in growth between crayfish in Bt and isogenic treatments. However, survivorship was 31 % lower in the Bt treatment compared with the isogenic treatment. These results suggest that the Bt corn and isogenic corn were of equivalent nutritional value but that Bt corn does have a toxic effect on rusty crayfish during long-term exposure.

Concepts: Agriculture, Bacillus thuringiensis, Genetically modified food, Invasive animal species, Ostrinia, European Corn Borer, Transgenic maize, Platanus occidentalis

7

Anthropogenic pollutants disrupt global biodiversity, and terrestrial sentinels of pollution can provide a warning system for ecosystem-wide contamination. This study sought to assess whether raccoons (Procyon lotor) are sentinels of local exposure to trace element contaminants at a coal fly ash site and whether exposure resulted in health impairment or changes in the intestinal helminth communities. We compared trace element accumulation and the impact on health responses and intestinal helminth communities of raccoons inhabiting contaminated and reference sites of the U.S. Department of Energy’s Savannah River Site (South Carolina, USA). Data on morphometry, hematology, histopathology, helminth community and abundance, and liver trace element burdens were collected from 15 raccoons captured adjacent to a coal fly ash basin and 11 raccoons from a comparable uncontaminated site nearby. Of eight trace elements analyzed, Cu, As, Se, and Pb were elevated in raccoons from the contaminated site. Raccoons from the contaminated site harbored higher helminth abundance than animals from the reference site and that abundance was positively associated with increased Cu concentrations. While we found changes in hematology associated with increased Se exposure, we did not find physiological or histological changes associated with higher levels of contaminants. Our results suggest that raccoons and their intestinal helminths act as sentinels of trace elements in the environment associated with coal fly ash contamination.

Concepts: Biodiversity, Carbon, Pollution, Coal, Fly ash, Pozzolana, Waste, Raccoon

5

We analyzed bat carcasses (Myotis lucifugus, M. sodalis, M. septentrionalis, and Eptesicus fuscus) from the northeastern United States for contaminants of emerging concern (CECs) such as polybrominated diphenyl ethers (PBDEs), and pharmaceuticals and personal care products. The CECs detected most frequently in samples were PBDEs (100 %), salicylic acid (81 %), thiabendazole (50 %), and caffeine (23 %). Other compounds detected in at least 15 % of bat samples were digoxigenin, ibuprofen, warfarin, penicillin V, testosterone, and N,N-diethyl-meta-toluamide (DEET). The CECs present at the highest geometric mean wet weight concentrations in bat carcasses were bisphenol A (397 ng/g), ΣPDBE congeners 28, 47, 99, 100, 153, and 154 (83.5 ng/g), triclosan (71.3 n/g), caffeine (68.3 ng/g), salicylic acid (66.4 ng/g), warfarin (57.6 ng/g), sulfathiazole (55.8 ng/g), tris(1-chloro-2-propyl) phosphate (53.8 ng/g), and DEET (37.2 ng/g). Bats frequently forage in aquatic and terrestrial habitats that may be subjected to discharges from wastewater-treatment plants, agricultural operations, and other point and nonpoint sources of contaminants. This study shows that some CECs are accumulating in the tissue of bats. We propose that CECs detected in bats have the potential to affect a number of physiological systems in bats including hibernation, immune function, and response to white-nose syndrome, a fungal disease causing population-level impacts to bats.

Concepts: Aspirin, Bat, Little brown bat, Fungal diseases, Hibernation, Bats, Indiana bat, White nose syndrome

3

Gulf menhaden (Brevoortia patronus) exhibited unprecedented juvenile recruitment in 2010 during the year of the Deepwater Horizon well blowout, exceeding the prior 39-year mean by more than four standard deviations near the Mississippi River. Abundance of that cohort remained exceptionally high for two subsequent years as recruits moved into older age classes. Such changes in this dominant forage fish population can be most parsimoniously explained as consequences of release from predation. Contact with crude oil induced high mortality of piscivorous seabirds, bottlenose dolphin (Tursiops truncatus), waders, and other fish-eating marsh birds, all of which are substantial consumers of Gulf menhaden. Diversions of fresh water from the Mississippi River to protect coastal marshes from oiling depressed salinities, impairing access to juvenile Gulf menhaden by aquatic predators that avoid low-salinity estuarine waters. These releases from predation led to an increase of Gulf menhaden biomass in 2011 to 2.4 million t, or more than twice the average biomass of 1.1 million t for the decade prior to 2010. Biomass increases of this magnitude in a major forage fish species suggest additional trophically linked effects at the population-, trophic-level and ecosystem scales, reflecting an heretofore little appreciated indirect effect that may be associated with major oil spills in highly productive marine waters.

Concepts: Petroleum, River, Florida, Mississippi, Louisiana, Gulf of Mexico, Mississippi River, Forage fish

3

Most studies on roadside soil pollution have been performed in areas where petrol is the main fuel. Very little work has been conducted in regions where diesel predominates. We collected soil samples from four sites that span a precipitation gradient along the Manali-Leh Highway in northwestern Himalaya, India. This road traverses rough terrain and most of the vehicles that travel along it are diesel-driven. At each site, we collected samples at incremental distances from the highway (0, 2, 5, 10, 20, and 150 m), and at each distance we collected samples from three depths (3, 9, and 15 cm). We assessed the concentrations of 10 heavy metals (Al, Fe, Cr, Cu, Pb, Ni, Co, Zn, V, and Ba), total sulphur, and total organic carbon (TOC) at each distance, and we measured the concentration of 16 polycyclic aromatic hydrocarbons (PAHs) at 2 m from the highway. Overall, we found that metal concentrations are low and there is no relationship between concentrations and distance from the highway, or depth within the soil profile. Sulphur concentrations, on the other hand, are high in roadside soils and there is a negative relationship between concentration and distance from the highway. PAH concentrations are low, but the proportion of different ringed species suggests that their source is anthropogenic. Correlations between TOC and the various pollutants further suggest that diesel vehicles and potentially biomass combustion are starting to affect the roadside environment in remote northwestern India. We suggest that pollutant concentrations be regularly monitored.

Concepts: Oxygen, Petroleum, Water pollution, Soil, Carbon, Polycyclic aromatic hydrocarbon, Pollution, Heavy metal music