Faecal Coliform Bacteria in Febros River (Northwest Portugal): Temporal Variation, Correlation with Water Parameters, and Species Identification

Febros river water was sampled weekly, during 35 successive weeks, and analyzed for microbiological (total coliforms, faecal coliforms, faecal streptococci and enterococci) and chemical-physical (ammonia and temperature) parameters. All microbiological parameters were highly correlated with each other and with ammonia, suggesting that the simultaneous determination of all variables currently in use in the evaluation of the microbiological quality of waters is probably redundant, and could be simplified, and that ammonia should be tested as a sentinel parameter of the microbiological pollution load of Febros river. From the strains isolated from positive tubes of the faecal coliforms test (multiple tube fermentation technique) and retested in this assay, Escherichia coli, Klebsiella oxytoca and Klebsiella pneumoniae subsp. pneumoniae strains were positive, indicating that the faecal coliforms test is not totally specific for Escherichia coli, and can detect other bacteria. Considering that these Klebsiella spp. are not necessarily of faecal origin, it was concluded that the faecal coliforms test can overestimate true faecal pollution. From the strains isolated from positive tubes of the faecal coliforms procedure, only Escherichia coli strains were clearly positive in the β-D-glucuronidase test. All other species were negative or very weakly positive, suggesting that the assay of the β-D-glucuronidase activity is less prone to false positives than the faecal coliforms test in the quantification of Escherichia coli in environmental waters.     

Lettuce plants as bioaccumulators of trace elements in a community of central Italy

A survey, based on the use of vascular plants to describe the distribution of selected elements (21 in total) was performed in 11 sites in the area of Castelfiorentino (Tuscany, Central Italy) differing for land use, from urban to industrial and rural areas. Lettuce plants grown under standardized conditions were positively used as biodeposimeters of airborne trace elements. Washing was found to be highly significant in reducing concentrations of many elements in the samples, suggesting a general surface contamination of leaves. The typical crustal element Al showed good correlations with Co, Fe, Li and V; on the contrary, Zn and Cd were intercorrelated and showed no connection with crustal indicators. Lead was still a relevant environmental presence, as the experiments were carried out before the ban of leaded gasoline. Source apportionment by factor analysis put in evidence a major contribution of crustal materials, followed by man-related activities; a minor role was ascertained for marine aerosol. A comparison was made between analytical data of lettuce plants grown in our experimental sites and a bulk of commercial lettuce purchased at a local supermarket. It should be stressed how Cu concentrations of commercial material were significantly higher than those found in our plants; this is likely caused by phytosanitary treatments.     

Selective collection as a pretreatment for indirect solid recovered fuel generation

Effective selective collection (SC) has been increasing in many countries of the European Union. As a consequence the composition of residual municipal solid waste (RMSW) is changing not only because of economic development, but also due to the collection system. The input of RMSW treatment plants is thus not homogeneous. This paper analyses two case studies involving a total of five SC scenarios and their impact on the generation of solid recovered fuel (SRF) with/without bio-drying, post-treatment and packaging take back programs (TBPs). These case studies are based on two types of SC: kerbside and drop-off. The latest regulation on SRF classification is taken into account: energy content, Cl and Hg concentrations are assessed and discussed. The role of the respirometric index (RI) is also analyzed. Results show that when SC is highly efficient RMSW can be classified directly as SRF, but only if the introduction of RI does not set stringent respirometric targets. The role of packaging TBPs is important as the residual waste remaining after the packaging has been processed, can be valorized increasing the lower heating value (LHV) of the residual RMSW and minimizing the streams that should be landfilled. The source separation of food waste has a significant impact on the suitability of bio-drying: when the SC of food waste is very efficient, its percentage in the RMSW may be too low for effective bio-drying.     

Bio-methane production from tomato pomace: preliminary evaluation of process intensification through ultrasound pre-treatment

Journal of Material Cycles and Waste Management - The effect of ultrasound pre-treatment (for 5, 15, and 30 min) on tomato pomace methane yield was evaluated. With respect to the control...     

The Impact of Biodegradable Plastics in the Properties of Recycled Polyethylene Terephthalate

Journal of Polymers and the Environment - Since biodegradable materials are unwittingly mixed with synthetic materials, this work aimed to study the feasibility of reliably identifying some...     

Partial neutralization of rain by seaspray: the case of Recôncavo, Bahia-Brazil

In the Recôncavo of Bahia (located between 12°33′ and 13°10′S and 38°00′and 39°00′W), there are significant discharges of SO₂ and NO_x due to local, industrial and urban activities. The incoming air masses from the Atlantic Ocean are enriched with seaspray, which neutralizes part of the rain acidity. The extent of seaspray neutralization of rain acidity was quantified in four sites of the region, each with different loads of seaspray. Rain samples were obtained daily at the same time, integrating the precipitation of the previous 24 h, using wet-only collectors and analyzed for pH by potentiometry and for sodium by flame photometry. The amount of rain acidity in Recôncavo neutralized by seaspray ranged from <1% up to 88% and depended on the site. On average, neutralization ranged from 5% to 18%.     

Waste foundry sand used to cover organic waste in landfills

Journal of Material Cycles and Waste Management - Waste foundry sand (WFS) is a waste generated during the molding of metal parts and primarily discarded in landfills, which generates environmental...     

Pollution status and risk assessment of trace elements in Portuguese water,soils, sediments,and associated biota: a trend analysis from the 80s to 2021

Pollution of water bodies and sediments/soils by trace elements remains a global threat and a serious environmental hazard to biodiversity and human’s health. Globalization and industrialization resulted in the increase and availability of these substances in the environment posing unpredictable adverse effects to living organisms. To determine pollution status and risk contamination by trace elements, data available in the literature of the last 40 years on trace elements occurrence in three environmental matrices (water bodies, sediments/soils, and biota) from Continental Portugal were collected (about 90 studies). Data were compared to water and sediment quality guidelines to assess potential ecological risks. Most environmentally relevant hazardous elements include Zn, Cu, Cd, Pb, and As. Various studies found trace elements at levels higher than those considered safe by environmental guidelines. In surface waters, Al, Zn, Se, and Ag were found above aquatic life limits in about 60% of the reviewed papers, while Cu, Zn, and As exceed those values in more than 60% of mining waters. Hg and Cd in sediments from mining areas exceeded aquatic life limits and potential ecological risk showed extremely high risk for most of the elements. The data compiled in this review is very heterogenous, varying in terms of sampling schemes, trace elements analysed, and spatiotemporal settings. This heterogenicity leads to data differences that make meaningful comparisons difficult. Nevertheless, the compilation of scattered environmental spatial and temporal trace elements data, of either natural sources or human activity as well as the ultimate effect on biological systems, is of the upmost importance to broaden its knowledge, risk assessment, and implementation of mitigation measures.

     

An Ecological Integrity Index for Littoral Wetlands in Agricultural Catchments of Semiarid Mediterranean Regions

The main goal of the present study was to develop an ecological integrity index for littoral wetland management and conservation in semiarid Mediterranean areas that have been highly impacted by agriculture, including the selection of pressure and state indicators at landscape and wetlands scales that reflect the status, condition, and trends of wetlands ecosystems. We used a causality framework based on the relationship between pressure of anthropogenic activities and the ecological state of wetlands and their catchments, integrating environmental, biologic, economic, and social issues. From the application of 51 indicators in 7 littoral wetlands in the southeastern Iberian Peninsula, we selected 12 indicators (5 at catchment scale and 7 at wetland scale) to constitute the ecological integrity index proposed. The potential nitrogen export per area at catchment scale and the potential relative nitrogen export from the area surrounding the wetlands were the best pressure single predictors of state indicators with a causal relationship with environmental meaning. Wetlands in catchments with more agriculture had less ecological integrity than those in less impacted areas. A wide riparian zone in some wetlands acts as a buffer area, diminishing the effects of intensive agriculture. The index of ecological integrity developed here has a number of essential characteristics that make it a useful tool for ecosystem managers and decision-makers. The index can be used to (1) assess and control ecological integrity, (2) diagnose probable causes of ecological impairment, (3) establish criteria for protecting and restoring wetland ecosystems, and (4) integrate catchment management. Published online     

Arsenic in sediments from the southeastern Baltic Sea

Arsenic occurs as a persistent constituent in many of the chemical weapons dumped into the Baltic Sea; it can be used as an indicator of leakage and dispersal of released munitions to the marine environment. Total arsenic was analysed in sediment samples taken from the Lithuanian economic zone in the Baltic Sea, which included samples from the chemical munitions dumpsite in the Gotland Basin and national monitoring stations in the southeastern Baltic Sea. Arsenic concentrations in sediments ranged from 1.1 to 19.0 mg kg(-1), with an average of 3.4 mg kg(-1). Although there was evidence of slightly elevated arsenic content in sediments near the weapons dumpsite, arsenic concentrations were nevertheless quite low relative to other investigations in the Baltic and North Seas.