RESEARCH

In the past decades, various treatments based on AOP, such as ozonation, peroxonation, and photocatalysis, have been developed to treat the persistent recalcitrant compounds (PrCs) in wastewater. In the initial stages, the disappearance of the parent compound was the priority, but later researchers understood the significance of the analysis of transformed products.  Uncertainty of the TPs formed after the AOP treatment process poses a barrier in understanding the efficiency of the process. In some cases, such as 17-β Ethyleneestradiol, diuron, erythromycin doxycycline on reacting with ROS resulted in a proportional loss of biological activity. TPs of Triclosan, ranitidine after oxidative treatment are more toxic than the parent compounds. TPs of very few PrCs were investigated in the whole universe of Compounds.  High-resolution LC-MS and GC-MS techniques in concomitant with data processing tools have been used to identify the TPs of several micropollutants. However, the selection of PrCs is random and very limited compared to the whole matrix of PrCs in the environment, and the number is increasing by the day. There is a severe gap in connecting the TPs and their toxicity which is essential to understand the efficiency of the wastewater treatment process. However, it is highly impractical and impossible to analyze all the existing PrCs.

Nevertheless, this study is essential as many countries adapt AOP-based wastewater treatment. Instead of selecting random PrCs, we focus on active functional moiety on the molecules responsible for toxicity. If we understand the fate of this moiety and toxicity of TPs prior to and after various treatments, the same pathway can be transferrable to all the molecules with similar moiety. We aim to create an online database connecting TPs' mechanistic pathways and toxicity after various AOPs for several active functional moieties. The first step is to select several active functional moieties in molecules responsible for toxicity which can be derived by pharmacokinetics and pharmacodynamics of individual drugs. Analytical tools such as GC-MS, LC-MS, and NMR will be utilized to understand the fate and mechanistic pathways for the degradation of PrCs. Toxicity studies will be performed for the samples before and after treatment to understand the efficiency of the process. For example, in our laboratory, we have applied filtration,  biodegradation, UV photolysis, homogenous and heterogeneous ozonation to cyclophosphamide in which mustard structure is active moiety and created a database about the fate of TPs after each process. This database can be adapted to other compounds with a mustard structure such as chlorambucil, melphalan, mechlorethamine, isofomide, melflufen, Bendamustine, Estramustine, Uramutine. After collecting the data, an artificial logarithm model will be created, as shown in the Figure, which can provide the TPs and their toxicity after each treatment. We know that this study is exhaustive ad requires a lot of lab, manual, analytical, and software programming. However, this is essential as more and more countries adopt AOP-based treatments as secondary (or) tertiary treatment processes. Several case studies conducted in France, Italy, Germany proved that more information on the fate of PrCs after treatment is essential where wastewater reclamation is one of the significant sources of water. The AI database integrating mechanistic pathways of TPs and the toxicity of PrCs is highly beneficial to the scientific community in developing novel AOP technologies to treat PrCs and understand the efficiency of the developed process.

The heavy metal chromium is stable at several valence states. The predominant state found in nature, trivalent chromium Cr(III), is an essential micronutrient, but the second most stable valence state, hexavalent chromium Cr(VI), is highly genotoxic and carcinogenic. Redox reactions that lead to Cr(III)-Cr(VI) interconversions are common, however, the favored reaction is a reduction of Cr(VI) to Cr(III) due to the greater reactivity of Cr (VI). The leather industry commonly uses trivalent chromium salts to tan animal hides, and oxidation of Cr(III) during this process or in the resulting wastewater could lead to the formation of Cr(VI) and introduction of both Cr(III) and Cr(VI) into the environment if tannery effluent is discharged without treatment or chromium removal. Further oxidation of Cr(III) to Cr(VI) by oxidizing agents present in the natural environment may occur.

            The Hebron stream is a transboundary ephemeral stream in Israel and the Palestinian territories that originates near the city of Hebron in the West Bank. The stream is highly polluted and receives year-round inputs of untreated sewage from Hebron city and contaminated effluents from the city’s industrial zone, including discharge from the tanning sector that contains significant levels of chromium. Previous studies conducted on the Hebron stream watershed have detected chromium in the waters and sediments of the stream, but have not attempted to characterize the valence state of this chromium or to explain the parameters and mechanisms governing its mobility and fate in the Hebron stream environment. Therefore, this research has attempted through fieldwork, lab analysis, and an in-depth literature review to detect and measure total chromium and Cr (VI) in the Hebron stream, and to explain the chemical mechanisms influencing the fate of chromium entering the stream.

Results:

• No Cr(VI) detected in stream or in effluent from sampled tanneries; total Cr detected in stream water ranged from 10-230 μg/L, 35-159 μg/g for sediment, and 1-7 μg/g for plants.
• Both stream water and tannery effluent possess characteristics that favor swift reduction of Cr(VI) to Cr (III) and precipitation or adsorption of Cr(III) compounds to the solid phase.
• High organic load of untreated sewage from Hebron city drives reduction of any Cr (VI) present in tannery discharge when the two effluents mix in the central sewer system.
• High concentrations of strong reductants such as iron and organic matter in both stream water and sediments contribute to the stream’s reducing environment.
• Cr (III) in the stream likely absorbs to suspended sediment or organic matter or precipitates as solid Cr(III) compounds, and depending on stream flow and turbidity, then remains as a solid-phase constituent of the water column or settles to the stream’s sediment bed.

No Cr detected in three drinking and irrigation wells sampled during the study, indicating that Cr is likely not entering groundwater despite prior studies showing that Hebron stream water does percolate into surrounding aquifers.

Figure 1: (Left) Calcium carbonate particulate deposits from the stone-cutting industry line the stream banks – these particulates may act as an adsorbent of Cr (III) in the stream and can become a major sink for Cr when they settle on the stream bed or banks. (Right) A goat herd grazes on plants growing by the stream, some goats even drink from the stream. While eating the plants and drinking stream water exposes the goats to Cr, Cr (III) is not readily absorbed in the GI tract and acidic conditions of the stomach would quickly reduce any Cr (VI) to Cr (III). (November, 2020).​​

A shortage of life-saving drugs, mostly oncology, is a known issue around the world for more than decay. Studies show that 70-90% of the drugs we take, leave our bodies reaching wastewater and flushed to municipal treatment plants. Many of those pharmaceuticals and prescription drugs residues, affecting plant, animal, and human health when they re-enter the water cycle and require high-cost removal processes. By applying the drug recovery process directly from patients' excretion or the hospital wastewater, it is possible to improve wastewater quality, reduce the treatment costs and produce a valuable high purity active pharmaceutical ingredient, which will be available for pharma industry or research institutes.

Electrically induced forces are playing a key role in biological systems, matching known theories of field-charge and field-dipole interactions. However, the specific interactions of induced and very low electromagnetic fields naturally present at the environment on living systems are not yet fully understood. The theory that in living systems have a certain coherent longitudinal electric modes are strongly excited, and stabilized by deformations arising from nonlinear effects was first subjected in the late sixties (Fröhlich, 1968). The sense of smell in that context is a great example of a biological sensor that can detect and diagnose an enormous number of airborne compounds. Odor vibrational theories trying to explain the elusive effects that cannot be explained by molecular structure alone.

Support to the existent of vibrational mode in living organisms at room temperature was recently published, using a large literature review Geesink (2016) shows that considering the effects of electromagnetic radiation on in vitro and in vivo life systems.  Hydrogen as the basic element has a key role for both biological and water structure, its ability to mediated from water to matter is important link between living matter, water, and waves was not yet specified. The main objective is to quantify the induced electromagnetic field and the vibrational modes in water and hydrogen, in particular, its function in transferring odor information and the effect on olfactory as a biological sensor.

Natural Fresh water supply is getting shorter worldwide, on the other hand the demand is getting higher. Therefore, there is a constant search for “production” of new sources for potable water and for ways to utilize every drop to the fullest, such as water reuse. In Israel up to 80% of the water is reused, wastewater is treated at the WWTP to high quality effluent and used mainly for agriculture. The effluent is spreading to the environment, to water sources, to the ground and to the crops human and animals consuming and, Whatever pollutants it may contain are spreading as well.

In this research we are focusing on the microbiological pollutant cryptosporidium. It is a protozoan parasite that infects humans and animals, it's environmental form, the oocyst, is very stable, and resistant to chlorine, the dis. Wastewater containing the oocysts, without a proper treatment, may cause a foodborne or waterborne cryptosporidium outbreak.

In the research we are measuring the prevalence of cryptosporidium in wastewater and tertiary effluent, the removal efficiency of different treatments and the presence of the parasite on crops and freshly eaten vegetables. We also use molecular biology to better understand which types of parasite we have and then compere it to other researches worldwide.