Comparative studies on accumulation of Cr from metal solution and tannery effluent under repeated metal exposure by aquatic plants: its toxic effects

The present study demonstrates comparison of Cr accumulatingpotential by the plants of Najas indica Cham. (submerged),Vallisneria spiralis L. (rooted submerged) and Alternanthera sessilis R. Br. (rooted emergent) under repeatedmetal exposure and its effect on chlorophyll and protein concentrations. These plants were treated with different concentrations of Cr under repeated exposure in controlled laboratory conditions to assess the maximum metal accumulationpotential. The plants of V. spiralis accumulated significantly high amount of Cr under laboratory conditions incomparison to N. indica and A. sessilis. The maximumaccumulation of 1378, 458 and 201 g g^-1 dw Cr was found in the leaves of V. spiralis, N. indica and A. sessilis, respectively at 8 mg L^-1 after 9 day of Cr exposure. These plants have shown a decrease in chlorophyll andprotein concentrations with increase in Cr concentrations. In view of high accumulation of Cr in V. spiralis, the plantswere treated with different concentrations of tannery effluent collected from Common Effluent Treatment Plant, Unnao (UP). Theplants of V. spiralis treated with 100% tannery wastewatershowed the maximum accumulation (57.5 g g^-1 dw) of Cr in the roots after 10 days of exposure. The plants were foundeffective in removing Cr from solution and tannery effluent.     

Effect of Fly-Ash on Metal Composition and Physiological Responses in Leucaena Leucocephala (Lamk.) de. Wit.

Plants of L. leucocephala were grown in 100%soil (as control), 100% fly-ash and fly-ash amendedwith 50% press mud for 80 days, and analysed withrespect to plant growth, elemental composition andphysiological changes in different parts of the plant.The results revealed that amending fly-ash with pressmud enhanced plant growth as well as otherphysiological responses such as chlorophyll, protein,in vivo nitrate reductase activity compared to100% fly-ash treated plants. The elements Fe, Zn, Cuand Mn accumulated in larger quantities in plantsgrown in 100% fly-ash, and followed the order ofaccumulation Fe > Zn > Cu > Mn. The results of thisstudy indicate that ash amending with press mud mayprovide more favourable conditions for the growth ofthis tree species.     

Influence of weight on the content of trace metals in tissues of Mytilus galloprovincialis (Lamarck, 1819): a forecast model

Fifty seven samples of Mytilus galloprovincialis (Lamarck, 1819) collected along the breakwater barriers of Fano (station 1) and Pesaro (station 2), Adriatic Sea, Marche Region, central Italy, were analyzed by atomic absorption spectrometry and Cd, Cu, Pb and Zn concentrations in the soft tissues were measured. The aims of this work were the statistical analysis of Cd-weight, Cu-weight, Pb-weight, Zn-weight relationships, and the building of a tendency function that allows assessing with a good approximation the concentrations of a metal in different weight organisms. In Mytilus galloprovincialis the content of Cd proportionally grew with the weight and therefore its concentration was independent from this factor; while the concentration of Pb decreased as the weight increased. In both cases the accuracy of multiple regression models improved considering the variable ‘site’, while the same approach appeared not reliable for Cu and Zn, that were two essential metals. Our results showed that a tendency function was reliable, solid and able to predict to a very satisfying extent the concentration of non-physiological metals, like Cd and Pb; while it did not show a good approximation with real Cu and Zn contents.     

Evaluation of Pb, Cu, Zn, Cd, Ni and Fe levels in Rosmarinus officinalis labaiatae (Rosemary) medicinal plant and soils in selected zones in Jordan

The concentration of heavy metals including Pb, Cu, Zn, Cd, Ni and Fe in different parts of Rosmarinus officinalis medicinal plant grown in Jordan were evaluated. Medicinal plant samples and soil samples were collected from three different zones in Jordan (Irbid, Al-Mafraq and Ma’an). Samples were analyzed by atomic absorption spectrometry (AAS) after chemical treatments using acid digestion procedures. Heavy metal levels in washed and unwashed in each part of R. officinalis were analyzed and compared statistically. Results show that concentrations of investigated heavy metals were varied from plant part to another part of R. officinalis. For example, Pb, Zn, Cu and Cd in most parts of R. officinalis in the three zones were concentrated in the following order: flowers, leaves, stems, whereas Pb, Ni and Fe were concentrated in order as follows: leaves, flowers and stems. Heavy metal concentrations in soil samples was evaluated and correlated with their levels in R. officinalis. Two standard reference materials of plant (SRM 1790a; spinach leaves and CRM 281; rye grass) and one standard reference materials of soil (GBW 07406) were examined to validate the method used. Results show that high recoveries were obtained.     

Seasonal Variation of the Particle Size Distribution of n-Alkanes and Polycyclic Aromatic Hydrocarbons (PAHs) in Urban Aerosol of Guangzhou, China

Seasonal aerosol samples have been collected by Andersen Hi-Vol pumping system equipped with a five stage cascade impactor and a backup filter (size range: 10–7.2 μ m, 7.2–3.0 μ m, 3.0–1.5 μ m, 1.5–0.95 μ m, 0.95–0.49 μ m, ≤0.49 μ m) in the Liwan district, Guangzhou. n-Alkanes were measured using gas chromatography and PAHs were measured using gas chromatography/mass spectrometry analysis. The bimodal log-normal distributions of n-alkanes and semi-volatile PAHs were found, while for non-volatile PAHs that was unimodal, so much as the mode of semi-volatile PAHs was similar with that of the particles. The n-alkanes and PAHs were preferably associated with fine particles. C _max (carbon number maximum) (C₂₂–C₂₆), CPI (carbon preference index) (1.12–1.21), U/R (unresolved to resolved components ratio) (7.42–10.7), wax% (0.9–3.12%) and the diagnostic ratios for PAHs revealed that vehicular emission was the major source of these organic compounds during the study periods, while the contribution of epicuticular waxes emitted by terrestrial plants was minor. CPI₂ (values for petrogenic hydrocarbons), CPI₃ (values for biogenic n-alkanes) and wax% revealed that the natural preferentially accumulated in the larger aerosol while the anthropogenic in the smaller. In addition, the different MMDs (mass median diameters) for n-alkanes and PAHs were observed in different seasons. The MMDs for n-alkanes and PAHs were higher in autumn/winter than those in spring/summer. The seasonal effect was related to the hydrocarbon content in the individual particulate fractions, showing a preferential association of n-alkanes and PAHs with larger particles in the autumn/winter season.     

Heavy Metal Concentrations in Water, Sediments and Body Tissues of Red Worm (Tubifex spp.) Collected from Natural Habitats in Mumbai, India

Live feeds, especially Tubifex spp., which are collected from a wide variety of polluted habitats, are used by aquarium fish keepers in India. These habitats receive domestic sewage and industrial wastes from nearby residential and industrial areas. Reports of morbidity and mortality from aquarium fish culturists in and around Mumbai led to the present investigations on the ecology of these habitats with a view to assess the water quality, presence of heavy metals in the environment and their bioaccumulation in Tubifex worms, and to examine whether these habitats could be exploited to meet the demand of the industry. Six natural red worm (Tubifex spp.) collection centres in Mumbai and Thane districts of Maharashtra state in India constituting a major source of live Tubifex supply to aquarium fish industry were evaluated for pollution, heavy metal concentration in water, sediments and in the body tissues of Tubifex. Data revealed the presence of heavy metals in water and sediments at collection sites and bioaccumulation of cadmium, iron, lead, zinc and copper in body tissues of Tubifex worms. Cadmium ranged from 2.38 to 7.21 mg/kg, iron 671.9 to 5738 mg/kg, lead 14.95 to 33.49 mg/kg, zinc 60.20 to 166.60 mg/kg and copper 29.38 to 108.90 mg/kg of dry Tubifex worms. The study suggests that all the six collection sites are polluted and the red worms contaminated with heavy metals and hence, unfit for use in aquaria or feeding any variety of fish or crustaceans in the hatcheries.     

Effects of Cadmium (CdCl2) on development and hatching of eggs in European squid (Loligo vulgaris Lamarck, 1798) (Cephalopoda: Loliginidae)

This is the first study related to the effects of cadmium (Cd) on the development and hatching of eggs of Loligo vulgaris. The eggs were exposed to concentrations varying from 10 to 100,000 μg Cd/l for up to 1 month. During the study period natural sea water salinity (37 PSU), ambient temperature (ranging 16.5–21.5°C) and light conditions of 12-h light: 12-h dark for 744-h were used prior to the hatching. For 96-h, mortality rate of 100% of the eggs was found at cadmium concentration of 100,000 μg Cd/l, and the same mortality rate of the eggs were found at 1,000 and 10,000 μg Cd/l for 744-h and 696-h, respectively. Hatching took place between hours 456 and 576 in the control group and between hours 480 and 576 in 10 and 100 μg Cd/l groups. Total hatching rates were calculated to be 98.2 ± 1.6% for control group, 99.4 ± 0.6% for 10 μg Cd/l group and 98.6 ± 1.2% for 100 μg Cd/l group. Hatching successes were estimated as 69.5 ± 13.8% for control group, 84.5 ± 8.2% for 10 μg Cd/l group and 76.9 ± 5.9% for 100 μg Cd/l group. In the 100,000 μg Cd/l treatment, the egg degeneration began from animal pole of the eggs in 16 h, and 50% and 100% of them died in the initial stage at 72-h and 96-h, respectively. In the 10,000 μg Cd/l group, the eggs which reached at stage 19 (IX) were deformed and 50% and 100% of them died at 312-h and 696-h, respectively. In 1,000 μg Cd/l group, however, the eggs developed abnormally from stage 21 (X–XI) and reached at stage 29 (XIX), and 50% and 100% of them died in 624-h and in 744-h, respectively. There were significant differences in survival rates of the eggs among the concentrations (p < 0.05). The current study demonstrated that Cd adversely affects the development, survival and hatching of L. vulgaris eggs; however, no mortality was observed in 10 μg Cd/l and 100 μg Cd/l groups.     

Variations in sensitivity of two populations of Corophium Orientale (Crustacea: Amphipoda) towards cadmium and sodium laurylsulphate

The aim of this work was to monitor the sensitivity of two populations of Corophium orientale (Crustacea: Amphipoda) living at the outfall of two rivers (Magra and Serchio), comparing their responses towards two different toxicant solutions. Sensitivity was monthly checked performing the 96h-LC₅₀ static water only test with Cd(NO₃)₂ and SDS. If no significant differences were found between the two populations, they could have been employed without distinction to perform sediment toxicity bioassays. As regard to Cd, an increasing in LC₅₀ values from summer to winter was evident in each population (Serchio River: August 2003  =  1,36 mg/l, February 2004  =  7,23 mg/l; Magra River: August  =  1,21 mg/l, April  =  5,01 mg/l). This pattern was correlated to the droop of temperatures in winter period. The responses of the two populations towards the cadmium were compared using the ANOVA. The analysis showed any significant differences between the populations (p  =  0.12). The pattern of sensitivity towards SDS for the population living on Magra River was similar to the same pattern found for Cd; as regard to the population living on Serchio River, data were not enough to describe the annual pattern. Anyway, statistical analysis was performed and no significant differences were found between the two populations (p  =  0.34).     

Distribution of Polycyclic Aromatic Hydrocarbons (PAHs) and phenolic endocrine disrupting chemicals in South and Southeast Asian mussels

A comprehensive monitoring survey for polycyclic aromatic hydrocarbons (PAHs) and phenolic endocrine disrupting chemicals (EDCs) utilizing mussels as sentinel organisms was conducted in South and Southeast Asia as a part of the Asian Mussel Watch project. Green mussel (Perna viridis) samples collected from a total of 48 locations in India, Indonesia, Singapore, Malaysia, Thailand, Cambodia, Vietnam, and the Philippines during 1994–1999 were analyzed for PAHs, EDCs including nonylphenol (NP), octylphenol (OP) and bisphenol A (BPA), and linear alkylbenzenes (LABs) as molecular markers for sewage. Concentrations of NP ranged from 18 to 643 ng/g-dry tissue. The highest levels of NP in Malaysia, Singapore, the Philippines, and Indonesia were comparable to those observed in Tokyo Bay. Elevated concentrations of EDCs were not observed in Vietnam and Cambodia, probably due to the lower extent of industrialization in these regions. No consistent relationship between concentrations of phenolic EDCs and LABs were found, suggesting that sewage is not a major source of EDCs. Concentrations of PAHs ranged from 11 to 1,133 ng/g-dry, which were categorized as “low to moderate” levels of pollution. The ratio of methylphenanthrenes to phenanthrene (MP/P ratio) was >1.0 in 20 out of 25 locations, indicating extensive input of petrogenic PAHs. This study provides a bench-mark for data on the distribution of anthropogenic contaminants in this region, which is essential in evaluating temporal and spatial variation and effect of future regulatory measures.     

Transport and Adhesion of Escherichia coli JM109 in Soil Aquifer Treatment (SAT): One-Dimensional Column Study

Bacteria transport and adhesion experiments under water-saturated and partially saturated conditions were examined over a wide range of ionic strength, from 1 to 100 mM KCl, CaCl₂, and MgCl₂, and at water contents of 0.15 and 0.22 in sand columns packed with three different sands, baked, sterilized, and raw sands in order to investigate the effects of ionic strength, water content, and porous media type on the microbial adhesion in soil aquifer treatment (SAT). Well-characterized Escherichia coli JM109 were used as model bacterial cells in this study. Column study results showed that bacterial deposition rates increased with increasing ionic strength and decreasing water content, and were higher in raw sand columns than those in other sand columns. The Derjaguin–Landau–Verwey–Overbeek (DLVO) theory was applied to experimental results in order to consider the interaction energies between the bacterial cells and collector grains; results revealed that a considerable amount of bacterial cells was weakly deposited onto the solid surfaces in secondary minimum.     

Faecal Coliforms in Bivalve Harvesting Areas of the Alvor Lagoon (Southern Portugal): Influence of Seasonal Variability and Urban Development

Faecal coliform (FC) levels in surface water and clams (Ruditapes decussatus) and variations in environmental parameters were studied in two bivalve harvesting areas in the Alvor lagoon (southern Portugal). Land use and cover characteristics in adjacent subwatersheds were also analysed to assess their contributions as sources of faecal contamination. High FC levels in clams from the harvesting area in the most urbanized subwatershed (impervious surface coverage ≈ 10.5%) were positively associated with rainfall and with the cooler periods of the year. FC levels in clams from the least urbanized subwatershed were generally very low and did not present any detectable seasonal trend. From these results, it was concluded that the periodic deterioration of the microbiological quality of clams derives from the cumulative impact of the reservoir of faecal contamination created in urbanized areas, entering into the lagoon during storm water runoff.     

Assessing effects of ambient ozone on injury and yield of bean with ethylenediurea (EDU): three years of plant monitoring at four sites in The Netherlands

EDU (ethylenediurea) and non-EDU-treated bean plants (Phaseolus vulgaris) L. cv. Lit) were exposed to ambient air at four rural sites in the Netherlands during the growing seasonsof 1994 through 1996 to investigate the responses to ambient ozone. Ozone-induced foliar injury was observed each year anddifferences in injury between sites depended on year. On average,injury amounted to 27% in 1994, to 8% in 1995 and to 1% in 1996. Injury increased with increasing ozone exposure (AOT40) and the estimated AOT40 value corresponding with 5% injury wascirca 3650 nl l^-1 h ozone. The highest ozone levels accumulated at each site for five consecutive days before injuryexceeded the proposed short-term critical level for injury development. EDU reduced injury and its protective effect was positively related to the injury intensity in non-EDU-treatedplants. Yield of green marketable pods (intermediate harvest) andmature pods (final harvest) was generally reduced in non-EDU-treated plants compared to EDU-treated plants and differences inyield reduction between harvests varied between years. The yield of mature pods was reduced in 1994 and 1996 while the yield ofgreen pods was reduced in 1995 by ozone only. Since yield reduction was not correlated with AOT40, the EDU method was notvalid to determine an ozone exposure-yield reponse relationshipfor bean.