Worldwide, crude palm oil industries generate an overwhelming amount of palm oil mill effluent (POME). Since the past few decades, environmental issues associated with POME disposal have challenged the palm oil-producing nations which led them to reevaluate and develop their waste management strategies by using advanced biotreatment technologies. With the help of these technological advances, POME has emerged as a valuable biomass resource with great potential to produce sustainable renewable resources like biogas. This review entails various POME treatment methods in vogue and offers an insight into their improved applicability potential and pollution mitigation strategies by using proposed improved configurations like ponding system, open digesting tanks, anaerobic digestion based-bioreactors, aerobic anaerobic hybrid bioreactors, and membrane bioreactors. This review paper also gives an overview about the recent advancements in POME treatment bioreactor configurations and emphasizing their scope in large-scale applications on an industrial level. This review also critically analyzes their performance level to achieve the standard POME discharge limit by efficiently removing high COD (chemical oxygen demand), BOD (biological oxygen demand), and TSS (total suspended solid).

A twelve year (2000−2011) study of three coastal lagoons in the Gulf of Mexico was conducted to assess the impacts of local watershed development and tropical storms on water quality. The lagoons have similar physical and hydrological characteristics, but differ substantially in the degree of watershed urban development and nutrient loading rates. In total the lagoons experienced 22 storm events during the period studied. Specifically, we examine (1) whether there are influences on water quality in the lagoons from watershed development, (2) whether there are influences on water quality in the lagoons from storm activity, and (3) whether water quality is affected to a greater degree by watershed development versus storm activity. The two urbanized lagoons typically showed higher water-column nitrate, dissolved organic nitrogen, and phosphate compared with the non-urbanized lagoon. One of the urbanized lagoons had higher water-column chlorophyll a concentrations than the other two lagoons on most sampling dates, and higher light extinction coefficients on some sampling dates. The non-urbanized lagoon had higher water-column dissolved oxygen concentrations than other lagoons on many sampling dates. Our results suggest long-term influences of watershed development on coastal water quality. We also found some evidence of significant storm effects on water quality, such as increased nitrate, phosphate, and dissolved oxygen, and decreased salinity and water temperature. However, the influences of watershed development on water quality were greater. These results suggest that changes in water quality induced by human watershed development pervade despite the storm effects. These findings may be useful for environmental management since they suggest that storms do not profoundly alter long-term changes in water quality that resulted from human development of watersheds.

Our previous study in 2011 reported the detection of BPA and PFAAs in 20 species of marine and freshwater fishes. With an emerging evidence to suggest the metabolic-disrupting effects of BPA/PFAAs in animals, the present study was aimed to provide a time-trend analysis to determine the current concentrations of PFAAs and BPA in 20 commercially available Hong Kong species of fishes. Since the manufacture and use of BPA is being prohibited in most nations, the introduction of BPA alternatives has recently been incorporated in the markets. Therefore, the concentrations of BPB, BPF and BPS were determined. In the present study, all freshwater and seawater fish samples showed quantified concentrations [>Limit of Quantification (LOQ<0.5ng/g)] of BPA. BPF was detected in some marine (yellow seafin, bigeye, goldspotted rabbitfish, snubnose pompano, tongue sole, Bleeker's grouper and orange-spotted grouper) and freshwater fishes (mud carp, crucian carp, tilapia, catfish, mandarin fish, grass carp, grey mullet and spotted snakehead). Two of the compounds, BPS and BPB could only be identified in the marine fishes (snubnose pompano, yellow seafin). In PFAA analysis, PFOA, PFDA, PFOS, PFUdA and PFDoA were found in most of the marine and freshwater fishes. PFOS and PFOA were shown to be the two predominant PFAAs in fishes. On the basis of the measured concentrations of bisphenols, BPs (BPA, BPB, BPF, BPS) and PFAAs, the average daily intake for BPs (20.5–31.5ng/kgb.w./day) and PFAAs (1.17–1.83ng/kgb.w./day) were calculated and found to be lower than values of tolerable daily intake (TDI) established in Europe. However, as compared with our previous study in 2011, the present study revealed an approximate 10-fold increase in the concentrations of BPA in the fish samples. Although the hazard ratio of consuming fishes for BPA and PFAA exposure is expected to remain low, possible additive metabolic-disrupting effect of BPA and its analogues as well PFAAs should be taken into consideration for human health risk assessment.

Ethylene is a ubiquitous industrial gas that is emitted by a wide variety of biogenic, biomass burning, and anthropogenic sources, so the opportunity for human exposure is widespread. We believe that a comprehensive exposure assessment of ethylene from emissions sources has not specifically been evaluated so this study was conducted to estimate the relative contribution of different sources on atmospheric concentrations in the Greater Houston area.Source attribution modeling shows that when averaged over the full modeling domain, inclusive of industrial, urban, rural and water areas, ethylene concentrations are dominated by natural source emissions (fires and biogenic) with an annual mean of 69% of total ethylene concentration. Of the anthropogenic sources, which account for the remaining 31% of the annual ethylene concentration, the largest contribution was from area/non-road sources (annual mean of 16%) with industrial source (annual mean of 11%) and on-road motor vehicle (annual mean of 4%) sources showing relatively lower concentration contributions.

Alkylated polycyclic aromatic hydrocarbons (PAHs) are abundant in petroleum, and alkylated phenanthrenes are considered as the primary PAHs during some oil spill events. Bacterial strain of Sphingobium sp. MP9-4, isolated from petroleum-contaminated soil, was efficient to degrade 1-methylphenanthrene (1-MP). A detailed metabolism map of 1-MP in this strain was delineated based on analysis of metabolites with gas chromatograph–mass spectrometer (GC–MS). 1-MP was initially oxidized via two different biochemical strategies, including benzene ring and methyl-group attacks. Benzene ring attack was initiated with dioxygenation of the non-methylated aromatic ring via similar degradation pathways of phenanthrene (PHE) by bacteria. For methyl-group attack, mono oxygenase system was involved and more diverse enzymes were needed than that of PHE degradation. This study enhances the understanding of the metabolic pathways of alkylated PAHs and shows the significant potential of Sphingobium sp. MP9-4 for the bioremediation of alkylated PAHs contaminated environments.

In June 2015, an individual of Diretmichthys parini (Post and Quero, 1981) was trawled at 530 m depth, in the North Sea off Norway and donated to research. This capture, the first for this species in the North Sea was the northernmost recorded so far, and provided an opportunity to document some aspects of the biology and ecology of this data-poor species. This individual was a female, 331 mm total length of 33 years old, with low mercury content in muscle and liver (~ 0.2 μg g− 1 wet mass). Stable isotope ratios (C and N) in muscle and liver were consistent with the planktonic diet expected for this species. The capture of this fish at the northern latitude known so far would be consistent with the extension of the home range and the latitudinal shift hypothesized for this species in the 1990′s.

Whether considered as a risk for human health or as ecological tracers, contaminants' concentrations measured in fish muscles are commonly expressed relative to wet or dry mass. Comparison of results required conversion factors (CF) but accurate values are scarce and case-specific. The present paper is aimed at investigating errors linked with the use of the theoretical value. Muscles dry and wet masses were measured in 15 fish species to determine the actual CF. Most CF were lower than the theoretical wet:dry ratio of 5 classically used, with variations at individual and species level. Muscle lipid content (inferred by C/N ratios) was a crucial factor explaining discrepancies, claiming for caution when working with lipid-rich species. The observed variability demonstrated that using the theoretical CF may be inaccurate, when actual CF largely differs from the theoretical value. Dedicated measurement is the better approach when accuracy is required.

The ultraviolet (UV)-based advanced oxidation process (AOP) is a powerful technology commonly utilised in recent potable water reuse (PR) schemes. The AOP involves the generation of highly reactive free radicals (e.g. hydroxyl, HO•) and is primarily applied for the removal of two target trace organic chemicals—N-nitrosodimethylamine (NDMA) and 1,4-dioxane — in the PR schemes. Both of these organics are not well removed by the reverse osmosis (RO) process. NDMA is a probable carcinogen and is often present in reclaimed water at concentrations higher than the guidelines established for PR. This review aimed to provide an understanding of the current UV-based advanced oxidation technologies for NDMA removal in PR, their limitations and the future of advanced technologies for their removal. NDMA is readily photolysed by direct UV irradiation, while an AOP such as UV/H₂O₂ process is necessary for the destruction of 1,4-dioxane. Unfortunately, the generation of hydroxyl radicals through UV photolysis of H₂O₂ is largely inefficient with conversion on the order of 20% under normal plant operations and the addition of H₂O₂ (e.g. 3 mg/L) provides only a negligible improvement in NDMA destruction. However, AOP can also be achieved without continuous chemical addition through the application of UV irradiation to heterogeneous photocatalysts (e.g. TiO₂). The UV/TiO₂ process generates hydroxyl radicals and singlet oxygen molecules, both of which degrade NDMA into by-products (e.g. methylamine or dimethylamine). Recent studies revealed that modification of the surface morphology of TiO₂ can not only enhance NDMA destruction but also alter the composition of the degradation by-products.

The characterization of inorganic elements in the produced water (PW) samples is a difficult task because of the complexity of the matrix. This work deals with a study of a methodology for dissolved Fe quantification in PW from oil industry by flame atomic absorption spectrometry (FAAS) after cloud point extraction (CPE). The procedure is based on the CPE using PAN as complexing agent and Triton X-114 as surfactant. The best conditions for Fe extraction parameters were studied using a Box-Behnken design. The proposed method presented a LOQ of 0.010μgmL−1 and LOD of 0.003μgmL−1. The precision of the method was evaluated in terms of repeatability, obtaining a coefficient of variation of 2.54%. The accuracy of the method was assessed by recovery experiments of Fe spiked that presented recovery of 103.28%. The method was applied with satisfactory performance to determine Fe by FAAS in PW samples.

We investigated the effect of combined exposure to nodavirus infection and TBT on medaka (Oryzias latipes). Medaka larvae were infected by immersion in medium containing nodavirus at titers of 102.5, 103.5, or 104.5 TCID50/mL. Infected fish then were exposed to TBT at 0, 0.17, 0.52, 1.6, or 4.7μg/L. Of the 12 groups exposed to both stressors, the mortalities of 6 (102.5 TCID50/mL+0.52, 1.6, or 4.7μg/L, 103.5 TCID50/mL+4.7μg/L and 104.5 TCID50/mL+1.6 or 4.7μg/L) were significantly higher than that of each TBT control. Specifically, mortality was 46±5.5% in the group exposed to both 102.5 TCID50/mL virus and 0.52μg/L TBT, which represent the lowest observed effective dose and concentration, respectively, among the 6 groups with increased mortalities. Our results suggest that combined exposure to both stressors suppresses antiviral mechanisms in the fish, thus increasing mortality.