In 2018, over 30,000 L of fluorine-free firefighting foam was used to extinguish an industrial warehouse fire of uncharacterized chemical and industrial waste. Contaminated firewater and runoff were discharged to an adjacent freshwater creek in Melbourne, Australia. In this study, we applied nontarget analysis using liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QToF-MS) to 15 surface water samples to investigate the presence of legacy, novel and emerging per-and polyfluoroalkyl substances (PFAS). We identified six novel and emerging fluorotelomer-based fluorosurfactants in the Australian environment for the first time, including: fluorotelomer sulfonamido betaines (FTABs or FTSA-PrB), fluorotelomer thioether amido sulfonic acids (FTSASs), and fluorotelomer sulfonyl amido sulfonic acids (FTSAS-So). Legacy PFAS including C₆–C₈ perfluoroalkyl sulfonic acids, C₄–C₁₀ perfluoroalkyl carboxylic acids, and perfluoro-4-ethylcyclohexanesulfonate were also detected in surface water. Of note, we report the first environmental detection of ethyl 2-ethenyl-2-fluoro-1-(trifluoromethyl) cyclopropane-1-carboxylate. Analysis of several Class B certified fluorine-free foam formulations allowed for use in Australia revealed that there was no detectable PFAS. Patterns in the homologue profiles of fluorotelomers detected in surface water are consistent with environments impacted by fluorinated aqueous film-forming foams. These results provide strong evidence that firewater runoff of stockpiled fluorinated firefighting foam was the dominant source of detectable PFAS to the surrounding environment.

By the year 2050, it is estimated that the demand for palm oil is expected to reach an enormous amount of 240 Mt. With a huge demand in the future for palm oil, it is expected that oil palm by-products will rise with the increasing demand. This represents a golden opportunity for sustainable biohydrogen production using oil palm biomass and palm oil mill effluent (POME) as the renewable feedstock. Among the different biological methods for biohydrogen production, dark fermentation and photo-fermentation have been widely studied for their potential to produce biohydrogen by using various waste materials as feedstock, including POME and oil palm biomass. However, the complex structure of oil palm biomass and POME, such as the lignocellulosic composition, limits fermentable substrate available for conversion to biohydrogen. Therefore, proper pre-treatment and suitable process conditions are crucial for effective biohydrogen generation from these feedstocks. In this review, the characteristics of palm oil industrial waste, the process used for biohydrogen production using palm oil industrial waste, their pros and cons, and the influence of various factors have been discussed, as well as a comparison between studies in terms of types of reactors, pre-treatment strategies, the microbial culture used, and optimum operating condition have been presented. Through biological production, hydrogen production rates up to 52 L-H₂/L-medium/h and 6 L-H₂/L-medium/h for solid and liquid palm oil industrial waste, respectively, can be achieved. In short, the continuous supply of palm oil production by-product and relatively, the low cost of the biological method for hydrogen production indicates the potential source of renewable energy.

The treatment of industrial waste and harmful bacteria is an important topic due to the release of toxins from the industrial pollutants that damage the water resources. These harmful sources frighten the life of every organism which was later developed as the carcinogenic and mutagenic agents. Therefore, the current study focuses on the breakdown or degradation of 4-chlorophenol and the antibacterial activity against Escherichia coli (E. coli). As a well-known catalyst, pure titanium-di-oxide (TiO₂) had not shown the photocatalytic activity in the visible light region. Hence, band position of TiO₂ need to be shifted to bring out the absorption in the visible light region. For this purpose, the n-type TiO₂ nanocrystalline material's band gap got varied by adding different ratios of p-type CuO. The result had appeared in the formation of p (CuO) – n (TiO₂) junction synthesized from sol-gel followed by chemical precipitation methods. The optical band gap value was determined by Kubelka-Munk (K-M) plot through UV–Vis diffusive reflectance spectroscopy (DRS). Further, the comprehensive mechanism and the results of photocatalytic and antibacterial activities were discussed in detail. These investigations are made for tuning the TiO₂ catalyst towards improving or eliminating the existing various environmental damages.

Soils containing a large proportion of industrial waste can pose a health risk due to high environmentally available concentrations of toxic metal(loid)s. Nano zero-valent iron (nZVI) and amorphous manganese oxide (AMO) were applied as immobilising amendments (1 wt%) to soils with different industrial origin of As and Sb, and leaching of As, Sb, Pb, and Zn was investigated using a single extraction with deionised water. The different industrial impact was reflected in the mineralogy, chemical composition and pH of these soils. Water-soluble As ratios positively correlated with pH in all experimental treatments. A significant decrease of water-soluble As ratios was observed in all nZVI-amended soils (~65–93% of the control) except for one sample with the lowest solution pH. Nano zero-valent iron was also successful in Sb immobilisation (~76–90% of the control). Highly variable results were obtained for AMO, which only led to a decrease of water-soluble As in soils with solution pH of ≥7 (~70–80% of the control), probably due to lower stability of AMO in acidic conditions. In each case, nZVI was more efficient at decreasing water-soluble As ratios than AMO. Dissolved Pb concentrations remained unchanged after the application of nZVI and AMO, and the decrease of Zn leaching using AMO was controlled mainly by soil pH increase induced by its application. According to the calculated saturation indices, tripuhyite (FeSbO₄) was predicted to be the key mineral controlling Sb solubility in mine soils. Secondary Fe (hydr)oxides either originally present or newly formed due to nZVI oxidation were instrumentally identified at different stages of their transformation and metal(loid) retention. To conclude, nZVI is suitable for application to contaminated soils at a wide pH range, while the use of AMO for decreasing As leaching is limited to soils with pH ≥ 7.

An industrial warehouse illegally storing a large quantity of unknown chemical and industrial waste ignited in an urban area in Melbourne, Australia. The multiday fire required firefighters to use large amounts of fluorine-free foam that carried contaminated firewater runoff into an adjacent freshwater creek. In this study, the occurrence and fate of 42 per- and polyfluoroalkyl substances (PFASs) was determined from triplicate surface water samples (n = 45) from five locations (upstream, point-source, downstream; 8 km) over three sampling campaigns from 2018 to 2020. Out of the 42 target PFASs, perfluorocarboxylates (PFCAs: C4–C14), perfluoroalkane sulfonates (PFSAs: C4–C10), and perfluoroalkyl acid precursors (e.g. 6:2 fluorotelomer sulfonate (6:2 FTSA)) were ubiquitously detected in surface waters (concentration ranges: <0.7–3000 ng/L). A significant difference in ΣPFAS concentration was observed at the point-source (mean 5500 ng/L; 95% CI: 4800, 6300) relative to upstream sites (mean 100 ng/L; 95% CI: 90, 110; p ≤ 0.001). The point-source ΣPFAS concentration decreased from 5500 ± 1200 ng/L to 960 ± 42 ng/L (−83%) after two months and to 430 ± 15 ng/L (−98%) two years later. 6:2 FTSA and perfluorooctanesulfonate (PFOS) dominated in surface water, representing on average 31% and 20% of the ΣPFAS, respectively. Emerging PFASs including a cyclic perfluoroalkanesulfonate (PFECHS) and a C4 perfluoroalkane sulfonamide (FBSA) were repeatedly present in surface water (concentration ranges <0.3–77 ng/L). According to the updated Australian PFAS guidelines for ecological conservation, the water samples collected at the time of monitoring may have posed a short-term risk to aquatic organisms in regard to PFOS levels. These results illustrate that acute high dose exposure to PFASs can result from industrial fires at sites storing or stockpiling PFAS-based waste products. Continued monitoring will be crucial to evaluate potential long-term risk to wildlife in the region.

Natural background levels (NBLs) and threshold values (TVs) are crucial parameters for identification and the quantification of groundwater pollution, and the evaluation of pollution control measures. The cumulative probability distribution technique was used for the evaluation of NBLs for 36 samples collected during two climate conditions in the part of the desert area from Rajasthan, India. The NBLs for Na⁺, Cl⁻, SO₄²⁻, HCO₃⁻, NO₃⁻ and F⁻ ions were assessed and compared with the natural and anthropogenic processes. The TVs were also calculated for Na⁺, Cl⁻, SO₄²⁻, HCO₃⁻, NO₃⁻ and F⁻ ions, and compared with the drinking limits of the Bureau of Indian Standards. Additionally, the pollution percentage (%) at the individual well was estimated and identified the polluted zones. Results indicate that most of the polluted areas were situated in the southern part, which was influenced by the natural and anthropogenic factors. The sodium concentrations above the TVs, in indicating the saline nature of water. Chloride threshold value above the drinking water limit was mainly observed in the dry season, related to intensive evaporation and industrial waste, which leads to groundwater quality degradation. The NO₃⁻ concentration (∼56% samples) above the TVs indicates extensive use of nitrate fertilizers and sewage effluent. The values of total dissolved solids (TDS) shows the suspicious scenario as about 84% of the samples in the dry period and about 89% in the wet season exceeding the drinking limit. Assessment of background concentrations and threshold values on regional and local scale assigns the basis for the identification of groundwater pollution, and helpful for better water quality guidelines to protecting of water resources.