Small wastewater treatment plants are often localized nearby tourist areas. Odour emissions are a major environmental issue in these plants and are considered to be the main cause of disturbance noticed by the exposed population. Odour measurement is carried out using analytical or sensorial methods. Sensorial analysis, being assigned to the "human sensor", is the cause of a considerable uncertainty.In this study, a novel procedure based on highly innovative analytical tool was used to identify and characterise the odour sources and the volatile substances that cause annoyance in a SWWTP located in a sensitive area, with the aim to remove the subjective component in the measure of the odours and define the induced impact. At the same time key odour compounds are detected, and the relationship between their concentration and the performances of the plant are investigated.The sources and the main chemical substances responsible for the olfactory annoyances were identified. Results highlight the applicability of the highly innovative tool in odour emission monitoring. Around 39 different substances were detected, with almost half being smell relevant components as well as responsible. Dimethyl disulphide was identified as key compound connected to the efficiency of the process.

The practice of use and disposal of waste from pharmaceuticals compromises the safety of the environment as well as representing a serious health risk, as they may accumulate and stay active for a long time in the aquatic environment. This article therefore presents the outcome of a study on pharmaceutical waste management practices at homes and hospitals in Ghana. The study was conducted at five healthcare institutions randomly selected in Ghana, namely two teaching hospitals (hospital A, hospital B), one regional hospital (hospital C), one district hospital (hospital D) and one quasi-governmental hospital (hospital E). Apart from hospital E which currently has a pharmaceutical waste separation programmr as well as drug return programme called DUMP (Disposal of Unused Medicines Program), all other hospitals visited do not have any separate collection and disposal programme for pharmaceutical waste. A survey was also carried out among the general public, involving the questioning of randomly selected participants in order to investigate the household disposal of unused and expired pharmaceuticals. The results from the survey showed that more than half of the respondents confirmed having unused, left-over or expired medicines at home and over 75% disposed of pharmaceutical waste through the normal waste bins which end up in the landfills or dump sites.

Photovoltaic modules contain hazardous substances such as lead and cadmium. Under normal operation conditions, these materials will not be released into the environment. This study identifies conditions resulting in release. Our worst case study uses milled module pieces of 0.2 mm size. Depending on the pH value of water based solutions, more or less amounts of hazardous substances are leached out. Solutions with low pH values (acidic solutions) yield substantial leaching. Three different solutions simulate different environmental conditions: i) "low mineralized water" conditions, via water containing sodium hydroxide, ii) "sea water" conditions, via water containing sodium hydroxide and sodium chloride, and iii) "rainwater" conditions, via water containing acetic acid. In "rain water"-like solutions with low pH, already after a few days, around 30 % of the cadmium is leached out from milled cadmium telluride module pieces, increasing to 50 % after 56 days! In the same time, more than 15 % of lead is leached out from c-Si module pieces. Tellurium elutes in the range of 30 to 40 % with a weak dependence on the pH value of the solution indicating an instability of the compound cadmiumtelluride out of the cadmiumtelluride modules. Most of the extractions increase during several weeks of measurement. Therefore, the usual one-day-elution test does not give enough information. Meaningful leaching experiments should last for at least ten days.

Anthropogenic Trace Compounds (ATCs) that continuously grow in numbers and concentrations are an emerging issue for water quality in both natural and technical environments. The complex web of exposure pathways as well as the variety in the chemical structure and potency of ATCs represents immense challenges for future research and policy initiatives. This review summarizes current trends and identifies knowledge gaps in innovative, effective monitoring and management strategies while addressing the research questions concerning ATC occurrence, fate, detection and toxicity. We highlight the progressing sensitivity of chemical analytics and the challenges in harmonization of sampling protocols and methods, as well as the need for ATC indicator substances to enable cross-national valid monitoring routine. Secondly, the status quo in ecotoxicology is described to advocate for a better implementation of long-term tests, to address toxicity on community and environmental as well as on human-health levels, and to adapt various test levels and endpoints. Moreover, we discuss potential sources of ATCs and the current removal efficiency of wastewater treatment plants (WWTPs) to indicate the most effective places and elimination strategies. Knowledge gaps in transport and/or detainment of ATCs through their passage in surface waters and groundwaters are further emphasized in relation to their physico-chemical properties, abiotic conditions and biological interactions in order to highlight fundamental research needs. Finally, we demonstrate the importance and remaining challenges of an appropriate ATC risk assessment since this will greatly assist in identifying the most urgent calls for action, in selecting the most promising measures, and in evaluating the success of implemented management strategies.

Odour emissions are a major environmental issue in wastewater treatment plants and are considered to be the main cause of disturbance noticed by the exposed population. Odour measurement is carried out using analytical or sensorial methods. Sensorial analysis, being assigned to the "human sensor", is the cause of a considerable uncertainty. In this study a correlation between analytical and sensorial methods was investigated. A novel tool was used to both define odour indexes and characterise the odour sources and the volatile substances that cause annoyance in a wastewater treatment plant, with the aim to remove the subjective component in the measure of the odours and define the induced impact. The sources and the main chemical substances responsible for the olfactory annoyances were identified. Around 36 different substances were detected, with more than half being smell relevant components as well as responsible. Dimethyl disulphide was identified as key compound. Results highlight the applicability of highly correlation between analytical and sensorial methods in odour emission monitoring.

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Septage is the solid sludge that accumulates in septic tanks over a period of time. Many of the developing countries in the world face the challenging task of septage management. Due to the high variability in the nature of septage, there is a need to study its physical and chemical characteristics in order to suggest a sustainable treatment methodology. The present study deals with the characterization of septage collected from different locations of Chennai city in India, in two different seasons (summer and winter). The characterization includes parameters such as solids, organics, inorganics, nutrients and heavy metals. Septage showed significant difference in concentrations of pollutants from one season to the other (p > 0.05). The average total solids concentration is found to be 1.6 times higher during winter season than compared to summer season. Average concentrations of solids were 2185 ± 1070 and 3555 ± 2935 mg/L during summer and winter, respectively. Liquid characterization of septage showed total chemical oxygen demands (COD) of 905 ± 603 mg/L (summer) and 1460 ± 1295 mg/L (winter). Similarly, average soluble biochemical oxygen demand (sBOD) was found to be 117 ± 54 mg/L during summer and 211 ± 220 mg/L during winter season. Studies also showed that septage was rich in nutrients such as total nitrogen (4-500 mg/L), ammoniacal nitrogen (2-129 mg/L), total phosphate (5-236 mg/L) and heavy metals such as copper, zinc, lead and manganese. Overall characterization indicates that the collected septage samples are highly variable in nature with respect to sources, season and locations of collection. As the septage is rich in organic matter and nutrients, it can be used as a resource like soil conditioner or as a substitute for chemical fertilizer in agriculture, after proper treatment, leading to a new evolution in sanitation.

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