Benjamin Matthew Long

Pharmaceuticals are pollutants that affect ecosystems and organism health, yet research on their trophic transfer remains limited, and often restricted to a few drug classes. Endorheic lakes, with minimal water outflow, provide an ideal but understudied setting for such investigations. We investigated eight pharmaceuticals in an effluent-influenced endorheic lake system in southeast Australia. Across four seasonal sampling events, we collected surface water samples, plant samples from five species (including Phragmites australis and Alisma lancelolatum), samples from biota, including glass shrimp, Paratya australiensis, three fish species (Cyprinus carpio, Gambusia affinis, Galaxias spp.), and invertebrates including spiders (Tetragnathidae). We found that seven of the eight pharmaceuticals analysed were detected in the surface water, flora and fauna. Concentrations ranged from at the limit of quantification (0.3–5 ng/L, all pharmaceuticals) to 159 ng/L (for tramadol). Concentrations decreased with distance from the outfall, posing a low risk for the environment. We detected pharmaceuticals in all biota except glass shrimp, with concentrations up to 1.5 ng/g (Carbamazepine in Phragmites australis). Pharmaceutical concentrations in Phragmites australis showed a unimodal relationship with leaf age. Food web analysis identified significant dilution of tramadol in the food web (trophic magnification factor = 0.63, p = 0.01), while no significant trophic movement was seen for carbamazepine (0.96). This is the first study to quantify and validate trophic magnification factors for a selection of pharmaceuticals in an Australian aquatic ecosystem. The results underscore a critical need to broaden investigation of pharmaceutical trophic magnification across lakes and other ecosystems.

Insects are crucial in the estimation of time-since-death of remains due to their predictable growth. Pharmaceuticals present in decomposing remains may alter insect growth and could affect postmortem interval calculations. Here we report on an investigation into the effects of trimethoprim, on the growth of Calliphora stygia (Fabricius, 1781) (Diptera; Calliphoridae) larvae, a common species of blow fly in Australia. We asked: (i) does trimethoprim influence larval growth, and (ii) can trimethoprim be detected in C. stygia larvae reared on trimethoprim? We found a significant increase in larval length in the trimethoprim-exposed group relative to the control group as accumulated degree hours increased. By mid-late experiment (~3,000 accumulative degree hours), larvae exposed to trimethoprim measured significantly longer than the control larvae; 15 to 18 mm (SD = 2.5 mm), representing a 164% increase compared to the control, which measured 11 to 13 mm (SD = 3.0 mm). We also observed a significant effect of trimethoprim on larval instar development and larval mass, however the latter was accompanied by higher variability. Additionally, trimethoprim was detected in all larvae (analyzed via HPLC–MS/MS) reared on antibiotic-treated substrates, indicating choice of growth models can be important when using larval length to estimate postmortem interval. Our findings highlight the potential for trimethoprim to affect larval growth of C. stygia, and likely other blow flies. This has implications for interpreting growth models used in postmortem interval estimations, and the need to expand knowledge of entomotoxicology into forensic investigations where data on the effects of pharmaceuticals on local insect species remains limited.

This study develops a pH-responsive label by incorporating anthocyanin from Clitoria ternatea into a bacterial nanocellulose (BNC) film derived from acid whey fermentation. The labels were designed to display two distinct colors—pink and purple—by adjusting the pH of anthocyanin and were integrated into beef mince packaging to monitor quality changes over a 15-day storage period at 4 °C. Color variations were assessed using a chroma meter and visual inspection, with both label types exhibiting a shift to blue in response to a deterioration in freshness. Significant differences (p < 0.05) in total color difference (∆E) were observed across data collection days. The pink label showed an ∆E of 14.19 between day 0 and day 8, increasing to 27.39 by day 15. The purple label exhibited an ∆E of 12.94 by day 8 and 27.86 by day 15. A Total Volatile Basic Nitrogen (TVBN) analysis and microbial evaluations confirmed a degradation in the quality of the beef mince, with strong correlations between ∆E and ∆TVBN (r = 0.956 for pink, r = 0.993 for purple). Additionally, good correlations were recorded between label total color differences and coliform counts (r = 0.933 for pink, r = 0.875 for purple), as well as Total Plate Counts (TPCs) (r = 0.982 for pink, r = 0.950 for purple). These results highlight the potential of acid whey-derived nanocellulose films as real-time quality indicators for intelligent food packaging systems.

Environmental context: Most human pharmaceutical waste is discharged to the environment. While the presence of pharmaceuticals in freshwater systems is well documented globally, little is known of the impact on marine ecosystems. We measured pharmaceuticals in a marine environment in south-eastern Australia and found pharmaceutical concentrations around 24 000 times higher in benthic flora than in the marine surface waters. We discuss the potential use of seaweeds as biological indicators of pharmaceutical pollution. Rationale: Pharmaceuticals are emerging pollutants of concern with a range of adverse consequences for organisms and ecosystems. Their presence in freshwater and estuarine systems has been well documented, but less is known about their prevalence in open ocean, or their uptake by benthic flora. This preliminary survey of the southern Australian coastline sought to measure the concentrations of key pharmaceuticals in both surface waters and benthic flora. Methodology: This study used LC-MS/MS to measure the concentration carbamazepine, tramadol and venlafaxine in (1) samples from wastewater treatment plants, (2) ocean surface waters and (3) several species of benthic flora. Surface waters and benthic flora were sampled at two sites near waste water treatment plant (WWTP) discharges, and one site away from any discharge. Results: All three pharmaceuticals were detected in surface water samples with their risk assessed (via risk quotient) as medium risk (carbamazepine) or low risk (venlafaxine, tramadol). All three pharmaceuticals were also detected in benthic flora, particularly in brown macroalgae; Tramadol was measured at a maximum of 34.7 ng g−1 in Hormosira banksii, and Venlafaxine was recorded at a maximum of 17.3 ng g−1 in Caulocystis cephalornithos. Discussion: The calculated bioconcentration factors suggest the pharmaceutical concentrations in benthic flora were up to ~24 000 times higher than in surrounding surface water. There was also evidence that proximity to WWTP outfalls influenced the levels of pharmaceuticals in benthic flora. The results suggest that the benthic flora may be suitable bioindicators of pharmaceutical contamination and that the potential impacts of pharmaceutical pollutants in marine ecosystems demand further investigation.

Metastatic tumours are complex ecosystems; a community of multiple cell types, including cancerous cells, fibroblasts, and immune cells that exist within a supportive and specific microenvironment. The interplay of these cells, together with tissue specific chemical, structural and temporal signals within a three-dimensional (3D) habitat, direct tumour cell behavior, a subtlety that can be easily lost in 2D tissue culture. Here, we investigate a significantly improved tool, consisting of a novel matrix of functionally programmed peptide sequences, self-assembled into a scaffold to enable the growth and the migration of multicellular lung tumour spheroids, as proof-of-concept. This 3D functional model aims to mimic the biological, chemical, and contextual cues of an in vivo tumor more closely than a typically used, unstructured hydrogel, allowing spatial and temporal activity modelling. This approach shows promise as a cancer model, enhancing current understandings of how tumours progress and spread over time within their microenvironment.

Small-angle X-ray scattering is used to unpack the hidden structure of a gelatin methacryloyl (GelMA) biogel. We present insights regarding how the degree of functionalisation, crosslinked polymer conformation, nanoscale mesh size and macroscale mechanical properties are interlinked.

Synthetic materials designed for improved biomimicry of the extracellular matrix must contain fibrous, bioactive, and mechanical cues. Self-assembly of low molecular weight gelator (LMWG) peptides Fmoc-DIKVAV (Fmoc-aspartic acid-isoleucine-lysine-valine-alanine-valine) and Fmoc-FRGDF (Fmoc-phenylalanine-arginine-glycine-aspartic acid-phenylalanine) creates fibrous and bioactive hydrogels. Polysaccharides such as agarose are biocompatible, degradable, and non-toxic. Agarose and these Fmoc-peptides have both demonstrated efficacy in vitro and in vivo. These materials have complementary properties; agarose has known mechanics in the physiological range but is inert and would benefit from bioactive and topographical cues found in the fibrous, protein-rich extracellular matrix. Fmoc-DIKVAV and Fmoc-FRGDF are synthetic self-assembling peptides that present bioactive cues “IKVAV” and “RGD” designed from the ECM proteins laminin and fibronectin. The work presented here demonstrates that the addition of agarose to Fmoc-DIKVAV and Fmoc-FRGDF results in physical characteristics that are dependent on agarose concentration. The networks are peptide-dominated at low agarose concentrations, and agarose-dominated at high agarose concentrations, resulting in distinct changes in structural morphology. Interestingly, at mid-range agarose concentration, a hybrid network is formed with structural similarities to both peptide and agarose systems, demonstrating reinforced mechanical properties. Bioactive-LMWG polysaccharide hydrogels demonstrate controllable microenvironmental properties, providing the ability for tissue-specific biomaterial design for tissue engineering and 3D cell culture.