Chronic risk assessment of exposure to volatile organic compounds in the atmosphere near the largest Mediterranean industrial site

This study focuses on characterising the risk of exposure to volatile organic compounds (VOCs) by means of inhalation in people living in the vicinity of the largest chemical production site in the Mediterranean area. Eighty-six VOCs were initially selected for this study based on their adverse environmental and health effects. The monitoring campaign was conducted for 276 days in three different locations around the chemical site. The analytical method used for the characterisation was based on European standard method EN-14662-2, which consists of the active sampling of air for 24 h in charcoal tubes, followed by extraction with carbon disulphide and GC-MS analysis. Forty-four VOCs with toxicological data available concerning their carcinogenic and non-carcinogenic health effects were quantified during the monitoring campaign. None of the quantified VOCs showed average concentrations exceeding their chronic reference concentrations and, therefore, no non-carcinogenic health effects are expected as a result of this exposure. However, the global average cancer risk due to VOC exposure in the area (3.3 × 10^− 4) was found to be above the values recommended by the WHO and USEPA.The influence of the analytical method was also evaluated by comparing cancer risk estimates using a thermal desorption (TD) method based on method EN-14662-1. The results of the 24-h samples for the solvent extraction method were compared with the average of 12 daily samples of 2-h for the TD method for 24 sampling days. Although the global estimated lifetime cancer risk was statistically comparable for both methods, some differences were found in individual VOC risks.To our knowledge, this is the first study that estimates the carcinogenic and non-carcinogenic risks posed by the inhalation of VOCs in people living near a chemical site of this size, and compares the estimated cancer risk obtained using two different standard analytical methods.     

Overview of the Belgian programme for the surveillance of the territory and the implications of the international recommendations or directives on the monitoring programme

The Royal Decree of 20th July has entrusted the Federal Agency for Nuclear Control (FANC) with the task of controlling the territorial radioactivity and the doses received by the population. Within this agenda, a monitoring programme has been developed over many years, in order to follow the main potential exposure pathways of the population. In practice, several potential vectors of contamination are controlled: air (and rain), surface water (including sediments and biota), soils around nuclear installations, food chain, drinking water etc. To carry out such work, the FANC has collaborated with public or private reputable organisations: The Centre of Nuclear Energy Studies of Mol, The National Institute of Radionuclides of Fleurus, and The Louis Pasteur Public Health Institute of Brussels. A synthesis of this monitoring programme will be presented and the most important deductions will be pointed out. For many years, the tendency has been for tighter control of artificial and natural radioactivity in the environment. This has been achieved by increasingly stringent regulations, regarding environmental monitoring efforts, from international organisations (EC, OSPAR, IAEA). In this context, the FANC in Belgium, is involved in a process that will lead to the adaptation of the Belgian monitoring programme. Different aspects of these adaptations and of their consequences will be presented for illustrative purposes.     

Molecular structures and associations of humic substances in the terrestrial environment

Here we show, for the first time, evidence of the primary molecular structures in humic substances (HS), the most abundant naturally occurring organic molecules on Earth, and their associations as mixtures in terrestrial systems. Multi-dimensional nuclear magnetic resonance (NMR) experiments show us that the major molecular structural components in the mixtures operationally defined as HS are aliphatic acids, ethers, esters and alcohols; aromatic lignin derived fragments; polysaccharides and polypeptides. By means of diffusion ordered spectroscopy, distinct diffusion coefficients consistent with relatively low molecular weight molecules were observed for all the components in the mixtures, and saccharides were the largest single class of component present. Liquid chromatography NMR confirmed that HS components can be easily separated and nuclear Overhauser effect (NOE) enhancements support the finding that the components are of relatively low molecular weight <~2,000 Da. The widely recognized properties of HS, i.e., characteristics indicative of crosslinked, macromolecular networks, can now be explained as aggregation of mixtures, most likely instigated by complexation with metal cations.     

Blood Pb and δ-ALAD inhibition in cattle and sheep from a Pb-polluted mining area

The effects of Pb pollution on cattle and sheep raised in an ancient mining area were studied through the use of blood Pb (PbB) levels and δ-aminolevulinic acid dehydratase (δ-ALAD) activity. Lead levels in livestock blood from the mining area (n=110) were significantly elevated when compared to the controls (n=79). In 91.4% of cattle (n=58) and 13.5% of sheep (n=52) sampled in the mining area, PbB levels corresponded to subclinical exposure (6-35 μg/dl). Two young cattle (<2 years) from the mining area (n=5) had PbB levels indicative of clinical poisoning (>35 μg/dl). Elevated PbB was also accompanied by δ-ALAD activity inhibition in blood, which confirms that measurable effects of Pb poisoning were taking place. Observed PbB levels suggest that a potential risk to human consumers of beef from the Pb polluted areas may also exist, as has been shown previously for game meat from the same mining area.     

Soil remediation time to achieve clean-up goals I: Influence of soil water content

The current models are not simple enough to allow a quick estimation of the remediation time. This work reports the development of an easy and relatively rapid procedure for the forecasting of the remediation time using vapour extraction. Sandy soils contaminated with cyclohexane and prepared with different water contents were studied. The remediation times estimated through the mathematical fitting of experimental results were compared with those of real soils. The main objectives were: (i) to predict, through a simple mathematical fitting, the remediation time of soils with water contents different from those used in the experiments; (ii) to analyse the influence of soil water content on the: (ii(1)) remediation time; (ii(2)) remediation efficiency; and (ii(3)) distribution of contaminants in the different phases present into the soil matrix after the remediation process. For sandy soils with negligible contents of clay and natural organic matter, artificially contaminated with cyclohexane before vapour extraction, it was concluded that (i) if the soil water content belonged to the range considered in the experiments with the prepared soils, then the remediation time of real soils of similar characteristics could be successfully predicted, with relative differences not higher than 10%, through a simple mathematical fitting of experimental results; (ii) increasing soil water content from 0% to 6% had the following consequences: (ii(1)) increased remediation time (1.8-4.9h, respectively); (ii(2)) decreased remediation efficiency (99-97%, respectively); and (ii(3)) decreased the amount of contaminant adsorbed onto the soil and in the non-aqueous liquid phase, thus increasing the amount of contaminant in the aqueous and gaseous phases.     

Elucidation of the behavior of tannery wastewater under advanced oxidation conditions

Diverse advanced oxidation process (AOP) techniques applying UV, TiO2/UV, O3 and O3/UV were used to degrade pollutants contained in tannery wastewater. The total mineralization of these pollutants is desirable, but it is quite energy consuming and sometimes impossible. Therefore the objective was to achieve an enhancement of biodegradability, preferentially with a decrease in toxicity in parallel. This work demonstrates that the dominant pollutants were chemically degraded by oxidation, while changes in carbon content were only marginal. These results were obtained monitoring the total organic carbon content (TOC), chemical and biochemical oxygen demand (COD and BOD), and substance-specific pollutant content by application of gas chromatography/mass spectrometry (GC-MS) and liquid chromatography/mass spectrometry (LC-MS). Daphnia magna toxicity testing performed in parallel proved a decrease in toxicity after AOP treatment of the tannery wastewater.     

Analysis of psychoactive substances and metabolites in sludges,soils, sediments and biota: a review

The use of psychoactive substances, including illegal drugs, drugs of abuse and psychiatric pharmaceuticals, is a major health and environmental issue. In particular, drugs are found in urban sewage and water ecosystems. The analysis of drugs in wastewater is challenging because drugs occur at trace levels in complex organo-mineral media, calling for advanced analytical methods. Here we review recent methods developped to analyze drugs in sludge, sediments, soils and biota. Extraction methods include solid–liquid extraction, sonication, microwave, and quick, easy, cheap, effective, rugged and safe extraction (QuEChERS). We compare and discuss advantages and disadvantages of each analytical step for various sample types.

     

Use of multicriteria decision aid methods in the context of sustainable innovations: bibliometrics,applications and trends

Environment Systems and Decisions - Sustainable innovation has gained prominence in recent years, due to the demands imposed by global competition, social pressures and the needs of consumers and...     

Kinetics assessment and modeling of biogas production by anaerobic digestion of food wastes and acclimated sewage sludge

Journal of Material Cycles and Waste Management - In this work, food wastes (FWs) and domestic sewage sludge (DSS) were used as raw materials for energy recovery by anaerobic digestion (AD). AD was...