Ambergris is a coprolith produced by some sperm whales (∼1 %). It has been hypothesised that the metals in ambergris derive from the haemolymph of squid in the whale diet (mainly copper). However, few data exist.
We report analysis of 10 trace metals in each of 50 ambergris samples by inductively coupled plasma-mass spectrometry.
Acid digests of the samples contained ∼5 to >6880 µg g−1 air-dried weight total metals; mainly of iron (present in ∼90 % of samples, 38), copper (∼95 % of samples, 40), zinc (93 % of samples, 39) and cadmium (∼95 % of samples, 40).
We suggest the variable and sometimes high concentrations of iron may reflect traces of haemoglobin or myoglobin from the whales. There may be other sources.
The other major metals (Zn, Cu, Cd) are those also reported in several squid species. The distributions are unlike those of squid haemolymph alone, reportedly dominated by copper, or those of the sperm whale (e.g., skin), dominated by zinc.
Anthropogenic activities, including those carried out by artisans, have been confirmed to be one of the various means by which potentially toxic elements (PTE) are introduced into the soil. This study aims to determine the PTE concentration and distribution in soils around artisans workshops in Ago-Iwoye, southwestern Nigeria.
Twenty (20) soil samples comprising ten (10) samples from soil around auto-mechanic workshops, six (6) from soils around vulcanizer workshops and four (4) from soils around welder workshops were collected and analyzed for elemental concentration using Inductively Coupled Plasma Mass Spectrometry (ICP-MS).
Elemental analysis revealed the following trend for selected metals in auto-mechanic, vulcanizing and welding workshops, respectively: Ba (60–100, 100–200 and 130–590 mg.kg−1); Co (10–47, 8–19 and 15–37 mg.kg−1); Cr (29–161, 22–95 and 57–272 mg.kg−1); Cu (28–123, 16–100 and 88–486 mg.kg−1); Ni (11–33, 7–29 and 34–112 mg.kg−1); Pb (17–75, 12–77 and 36–677 mg.kg−1); Sc (2–16, 1–7 and 2–8 mg.kg−1); Sr (13–55, 17–72 and 33–91 mg.kg−1); V (35–212, 20–117 and 40–103 mg.kg−1) and Zn (82–684, 70–548 and 314–3240 mg.kg−1). Geochemical assessment using contamination factor, and geo-accumulation index showed that the artisanal workshops exhibited significant contamination levels for metals such as Ba, Cu, Ni, Pb, Sr, and Zn and the contamination level varied across the artisan workshops with soils around welders workshops showing highest contamination.
Contamination indices revealed the artisan workshops have varying contribution to the metal load in the area and Pollution Load Index (PLI) indicated a decline in soil quality across all artisanal workshops with welding workshops revealing the highest anthropogenic contribution of PTE to the soil.
Metal pollution is a problem in many parts of the world. These metals can be harmful when they exceed the recommended limits. This study aimed to assess the levels of cadmium (Cd), mercury (Hg), and lead (Pb) in the tissues of oysters (Crassostrea virginica) within a protected area in southeastern Mexico. Additionally, the study aimed to conduct a risk analysis for human health associated with these metals. It is anticipated that the observed metal levels will be lower compared to prior studies, thereby not posing a significant risk to the local population.
The tissue of oyster samples was treated under the techniques of the Official Mexican Standards and analyzed using atomic absorption spectroscopy. The metal concentrations were used to calculate the estimated daily intakes (EDI), target hazard quotients (THQ), hazard index (HI), and target cancer risks (TR), for children and adults.
Maximum values of Cd (1.99 μg g−1), exceeded the permissible limits of the Official Mexican Standards. Pb (0.99 μg g−1) and Hg (0.64 μg g−1) are within the recommended limits. The THQ and HI for Cd, Pb, and Hg were lower than the United States Environmental Protection Agency (US-EPA) criteria.
Based on our results, whether oyster (Crassostrea virginica) consumption is recommended in adults and reducing consumption in children; to diminish the risk of exposure to Cd, Pb, and Hg.
This research employs response surface methodology, specifically Central Composite Design (CCD), to optimize the process parameters for the effective production of biodiesel. Jatropha oil was utilized as the raw material to minimize expenses. A nanocatalyst was utilized as a solid catalyst, developed from CaCO3 via waste snail shells, offering advantages such as recyclability and improved catalytic activity during a transesterification process. The developed nanocatalyst was analyzed using various techniques, including dynamic light scattering (DLS), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) analysis, and Fourier-transform infrared (FTIR). The BET analysis revealed a surface area of 5.1m2/g and the Barrett-Joyner-Halenda (BJH) analysis provided insights into the pore volume and diameter of the synthesized nano-CaO, showing values of 0.002556 cc/g and 1.1 nm, respectively, indicating the presence of both microspores and active sites on the external surface of the nano-CaO catalyst. Biodiesel conversion was controlled by adjusting factors like the methanol to oil ratio, catalyst weight, reaction time, reaction temperature, and agitation speed. A quadratic model was established to explore the correlation between the independent variables and the biodiesel conversion rate. The results showed a maximum biodiesel conversion rate of 96.73% under the optimal conditions: methanol to oil ratio (6:1), catalyst weight (1.4 wt%), reaction time (60 min), reaction temperature (55 °C), and agitation speed (250 rpm). These parameters were determined through 32 experimental trials. The RSM technique yielded impressive results with a determined coefficient of determination (R2) of 0.9834, adjusted R2 of 0.8503, predicted R2 of 0.8309, and a coefficient of variance (CV) 0.75%. Based on the analysis of variance (ANOVA) findings, the model exhibits a high level of significance (p<0.0001), which is less than 0.05 and F- Value 29.71.The study aims to enhance the yield and efficiency of the transesterification process, thereby increasing the overall production of fatty acid methyl ester from Jatropha oil. This innovative approach efficiently generates biodiesel from renewable resources, in a manner that is both environmentally friendly and maximizes the effectiveness of the process parameters. The evaluation conform that the quality of the biodiesel met the standards set by ASTM D 6751 and EN 14214.
Trace metal deficiency has become a major constraint on the productivity and sustainability of soils. Agriculture becomes more complex, advanced and intensive farming systems develop, however, the deficiency of trace metal are more frequent and extensive in different systems.
This study investigated the variation of trace metal minerals in soil profiles of diverse land use systems (LUSs), i.e. agriculture, horticulture and forestry, falling under three dominant soil orders (Entisol, Inceptisol and Aridisol) in Malwa region of Punjab. Through comprehensive analyses, we explore the intricate relationships between soil characteristics, land use practices, and the distribution of key trace metals—namely zinc (Zn), copper (Cu), iron (Fe) and manganese (Mn).
The mean values of DTPA-extractable trace metal from soil profiles of different land uses varied from 1.75 to 2.09, 1.64–2.32, 1.18–1.69 mg kg−1 for Zn; 0.59–1.02, 0.59–0.99, 0.64–0.92 mg kg−1 for Cu; 12.12–16.49, 9.84–16.05, 7.94–11.56 mg kg−1 for Fe; 7.82–9.99, 4.66–9.39, 6.51–7.46 mg kg−1for Mn in soil orders Entisol, Inceptisol and Aridisol, respectively. The concentration of trace metals in different soil orders follows the pattern of ntisol>Inceptisol>Aridisol. In contrast, there is a considerable amount of variation and no discernible pattern in the distribution of trace metals under various LUSs in each soil order. Several LUSs were examined, and agriculture land use system (ALUS) had the greatest Fe and Mn content, while the horticulture land use system (HLUS) had the highest Zn and Cu content. The Irrespective of soil orders and LUSs, the concentration of trace metals decreased as soil depth increased. Diverse LUSs and management practices have a substantial impact on the physico-chemical characteristics of soils, which in turn influence the availability of trace metals. According to the Pearson correlation studies, trace metals were positively associated with soil OC and negatively associated with soil pH, electrical conductivity (EC), and calcium carbonate (CaCO3) and there was also a positive correlation between DTPA-Zn, Cu, Fe, and Mn in the investigated soils. The results of the principal component analysis (PCA) revealed that soil CaCO3 and organic carbon (OC) content were the most variable soil parameters influencing crop trace metal availability in different soil orders and land use systems.
The findings contribute to a nuanced understanding of the dynamic interplay between soil properties and land use, providing valuable insights for sustainable agricultural practices and environmental management in the region.

