Hazardous Waste Management

This book presents a comprehensive overview of hazardous waste and hazardous waste management. It describes the various types and constituents of hazardous waste, discusses hazardous waste management techniques and technologies, and highlights techno-economic considerations and key issues in remediation. It is a useful resource for waste management and treatment professionals, chemical engineers, technicians, medical professionals, and environmental regulators as well as students studying hazardous waste management, environmental engineering, and environmental science

Review of risk from potential emerging contaminants in UK groundwater

This paper provides a review of the types of emerging organic groundwater contaminants (EGCs) which are beginning to be found in the UK. EGCs are compounds being found in groundwater that were previously not detectable or known to be significant and can come from agricultural, urban and rural point sources. EGCs include nanomaterials, pesticides, pharmaceuticals, industrial compounds, personal care products, fragrances, water treatment by-products, flame retardants and surfactants, as well as caffeine and nicotine. Many are relatively small polar molecules which may not be effectively removed by drinking water treatment. Data from the UK Environment Agency’s groundwater screening programme for organic pollutants found within the 30 most frequently detected compounds a number of EGCs such as pesticide metabolites, caffeine and DEET. Specific determinands frequently detected include pesticides metabolites, pharmaceuticals including carbamazepine and triclosan, nicotine, food additives and alkyl phosphates. This paper discusses the routes by which these compounds enter groundwater, their toxicity and potential risks to drinking water and the environment. It identifies challenges that need to be met to minimise risk to drinking water and ecosystems

Oestrogen, testosterone, cytotoxin and cholinesterase inhibitor removal during reclamation of sewage to drinking water

Namibia is the driest sub-Saharan country in Africa. Namibia’s capital, Windhoek, reclaims sewage water for domestic use at the Goreangab Water Reclamation Plant (GWRP). Risks associated with sewage effluent and reclaimed sewage should be closely monitored; therefore water at the Gammams Sewage Treatment Plant (GSTP) inlet and outlet, as well as reclaimed water from the GWRP, were assayed using selected bioassays. Samples collected were analysed using enzyme-linked immunosorbent-assays and chromogenic tests for steroid hormones, neurotoxicity, cytotoxicity and inflammatory activity. Estradiol level at the sewage treatment inlet was 78 pg/mℓ and the treated sewage level showed an 83% to 95% reduction in this, while after reclamation the level was below detection limit. Estrone concentrations at the sewage treatment inlet ranged from 10 to 161 pg/mℓ. Sewage treatment reduced estrone by between 85% and 92%. After reclamation the level of estrone was below detection limit. Testosterone ranged between 162 and 405 pg/mℓ at the sewage plant inlet. Sewage treatment removed 96% of the initial testosterone. The residual testosterone was effectively removed by processes in GWRP and after reclamation no testosterone was detected in water. Acetylcholinesterase (AChE) inhibition at the sewage treatment inlet was 50% while it was only 27% after sewage treatment. After reclamation AChE inhibition was not detected. Only water at the sewage inlet in March and February showed cytotoxicity. High inflammatory activity was detected at the sewage plant inlet. Sewage treatment reduced inflammatory activity by 64%. After reclamation low inflammatory activity was induced. Treated sewage used for reclamation tested positive for most of the biomarkers and can pose a risk to human health. However, reclamation successfully removed these contaminants. Due to the presence of contaminants in the intake water at the reclamation plant, it is essential to routinely monitor the water produced by the reclamation plant for potential residues that can adversely affect human health.Web of Scienc

Origin, environmental presence and health effects of microplastics

Microplastics (MPs) – consisting of small plastic particles with size less than 5 mm – have become ubiquitous environmental contaminants. Even though plastics are mass produced and proved to be useful in many applications, they may have potentially negative impacts on environment and human health. Multiple sizes, shapes, and polymer types, and their various sources can influence the environmental and human health effects of MPs. Being present in oceans, freshwater, soils and air, MPs can cause human exposure via ingestion, inhalation, and dermal contact, resulting possibly in oxidative stress, inflammation, altered balance in metabolism and immune system, neurotoxicity, reproductive toxicity, and cancer risk. Also, MPs can act as vectors of toxicants or microorganisms. All the same, public awareness towards MPs is currently low, and a lot of studies related to MPs are still ongoing. Further research is needed for a better understanding of MPs’ occurrence in environmental systems and their human health effects

Origin, environmental presence and health effects of microplastics

Microplastics (MPs) – consisting of small plastic particles with size less than 5 mm – have become ubiquitous environmental contaminants. Even though plastics are mass produced and proved to be useful in many applications, they may have potentially negative impacts on environment and human health. Multiple sizes, shapes, and polymer types, and their various sources can influence the environmental and human health effects of MPs. Being present in oceans, freshwater, soils and air, MPs can cause human exposure via ingestion, inhalation, and dermal contact, resulting possibly in oxidative stress, inflammation, altered balance in metabolism and immune system, neurotoxicity, reproductive toxicity, and cancer risk. Also, MPs can act as vectors of toxicants or microorganisms. All the same, public awareness towards MPs is currently low, and a lot of studies related to MPs are still ongoing. Further research is needed for a better understanding of MPs’ occurrence in environmental systems and their human health effects

Brominated Flame Retardants – Endocrine-Disrupting Chemicals in the Swiss Environment

Brominated flame retardants (BFR) are additives used to protect plastic materials and textiles against ignition. As some widely used BFR have chemical structures similar to well known endocrine disruptors such as polychlorinated biphenyls (PCB) or bisphenol A, adverse effects were also presumed for BFR. When the NRP50 programme started in 2001, the sparse knowledge on environmental behavior and toxicology of BFR did not allow a proper assessment of the risks associated with the widespread use of these chemicals. Therefore, we proposed to address questions such as the exposure of animals and humans, temporal trends in the environment as well as transformation and transport processes of BFR. Concentrations of BFR in wildlife and humans in Switzerland today pose no serious concerns for negative health effects according to the current knowledge on the toxicity of BFR. However, negative health effects cannot be ruled out in the future, since some BFR persist in the environment and their concentrations in freshwater lake sediments are increasing rapidly. The development of environmentally safe alternatives to these chemicals will be an important issue for the future

Hazardous contaminants in plastics contained in compost and agricultural soil

Macro-, meso-and microplastic (MAP, MEP, MP) occurrence in compost is an environmental issue whose extent and effects are not yet understood. Here, we studied the occurrence of MAPs, MEPs and MPs in compost samples, and the transfer of hazardous contaminants from plastics to compost and soil. MAPs/MEPs and MPs concentrations in compost were 6.5 g/kg and 6.6 +/- 1.5 pieces/kg; from common recommendations for compost application, we estimated similar to 4-23 x 10(7) pieces MPs and 4-29 x 10(4) g MAPs/MEPs ha(-1) per year ending into agricultural soils fertilized with such compost. Regarding contaminants, bis(ethylhexyl) phthalate, acetyl tributyl citrate, dodecane and nonanal were extracted in higher concentrations from plastics and plastic-contaminated compost than from compost where MAPs/MEPs had been removed prior to extraction and analysis. However, some contaminants were present even after MAPs/MEPs removal, ascribable to short-and long-term release by MAPs/MEPs, and to the presence of MPs. DEHP concentration was higher in soils where compost was applied than in fields where it was not used. These results, along with estimations of plastic load to soil from the use of compost, show that compost application is a source of plastic pollution into agricultural fields, and that plastic might transfer hazardous contaminants to soil.Peer reviewe

Emerging contaminants in biosolids: presence, fate and analytical techniques

Emerging contaminants (ECs) represent a small fraction of the large chemical pollution puzzle where a wide variety of potentially hazardous chemicals reach the environment, and new compounds are continuously synthesized and released in wastewater treatment plants and ultimately in effluent and biosolids. ECs have been classified into various categories; however, this article focuses on the fate of major categories, namely pharmaceutical and personal care products (PPCPs), per-and poly-fluoroalkyl substances (PFAS), flame retardants, surfactants, endocrine-disrupting chemicals (EDCs), and microplastics (MPs). These ECs when discharged to sewer and downstream wastewater treatment plants can undergo further transformations and either degrade, persist or convert into by-products which have the potential in some cases to be more hazardous. Because of potential dangerous impacts of the availability of these contaminants in the environment, information on the fate and behavior of these pollutants is highly important to develop new strategies, such as the regulation of chemicals imported into Australia and Australian consumer goods and environmental policies to mitigate them in a sustainable way. Moreover, advanced technologies are required for the detection and identification of novel contaminants emerging in the environment at ultra low levels. The application of chromatographic techniques coupled with mass spectroscopy has provided attractive breakthroughs to detect new emerging contaminants. However, it is crucially important to understand the sensitivity and robustness of these analytical techniques when dealing with complex matrices such as biosolids. In addition, most of the literature was focused on selected compounds or a family of compounds and the existing reviews have paid less attention to examine the formation of metabolites during the wastewater treatment process and their impacts on the ecosystem. This review presents an overview of the presence of different classes of ECs around the world, their quantification from different sources like wastewater (influents or effluents), sludge and biosolids. In addition, the transformation of ECs during the treatment process, the formation of intermediate products and their impacts on the environment are also critically discussed. Three major steps of ECs analysis include sample preparation, extraction and clean-up, and analysis; hence, different methods employed for extraction and clean-up, and analytical techniques for identification are thoroughly discussed, their advantages and limitations are also highlighted. This comprehensive review article is believed to enhance the understanding of ECs in sewage sludge and would be useful to the readers of the relevant communities and various stakeholders to investigate potential technologies to maximize destruction of ECs