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The use of vegetable tanning materials in leather processing has drawn attention as an alternative to basic chromium sulphate for its natural abundance and environmental aspects. In this work, an attempt has been made to extract vegetable tannins from Xylocarpus granatum bark using different solvents (e.g., water, methanol, ethanol, and chloroform) and compare with conventional vegetable tanning agents such as mimosa and quebracho. The highest extraction efficiency was observed 31.22% by methanol. The presence of tannin content and polyphenolic compounds, e.g. (-)epicatechin (503 mg/100 g dry extract), catechin hydrate (218 mg/100 g dry extract), catechol (29 mg/100 g dry extract) were ensured by UV–Vis, FT-IR spectroscopy and HPLC. Again, condensed tannins, moisture content, and pH of the methanol extracted tannin were found 47.80%, 5.82%, and 3.97 respectively. The leather tanned by Xylocarpus granatum tannin showed a shrinkage temperature of 86.34 ± 1.52 °C. Other properties such as tensile strength, tear strength, grain cracking load, and distention at grain cracking were comparable to conventional vegetable-tanned leather. The cross-sectional morphology of the tanned leathers was also characterized by scanning electron microscopy (SEM) which revealed a compact structure of the leather fibers. In light of the findings from the study, X. granatum bark tannin could be a well alternative to chromium and a new source of vegetable tannin for the leather industry. Graphical Abstract

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Worldwide, tannery sludge management has become a big challenge due to containing heavy metals, especially chromium. In this study, phytoextraction of heavy metals from tannery sludge by Napier grass (Pennisetum purpureum) is presented.Heavy metals-chromium (Cr), copper (Cu), zinc (Zn), and lead (Pb) in tannery sludge were found at 12686, 371, 265, and 66 mg/kg, respectively. Separately, Napier grass was harvested on raw tannery sludge and garden soil and examined for 16 and 20 weeks after the sowing of seeds. Metal extraction from tannery sludge in Napier

Soil and plant samples collected from Hazaribagh, the former tannery area in Dhaka, Bangladesh, were analyzed for heavy metals (Cr, Pb, Ni, Zn, Cd, and Cu). The pollution and health risks of the metals were assessed with commonly used indicators. The mean soil Cr concentration was 4321 mg/kg (range 294-23,148 mg/kg). Most sites had a moderate to high degree of contamination and were classified as extremely polluted (Pollution Load Index > 1). The non-carcinogenic hazard index was greater than 1 for Pb and Cr for both children and adults, which indicates considerable non-cancer health risk. The combined cancer risks for Pb and Cr exceeded the allowable range of 1 × 10 −6-1 × 10 −4 for most sites (8 out of 11 sites in the case of adults, all sites in the case of children) with Cr being the dominant contributor and oral ingestion the primary pathway. The cancer and non-cancer risks for children were 26-and 3-fold higher, respectively, than for adults. Among all heavy metals, Pb and Zn were the most susceptible to leaching and becoming mobilized in groundwater. Concentrations of Pb, Cr, and Zn in edible parts of vine spinach (Basella alba) exceeded safe limits. However, Pb and Cu showed significant accumulation in plants (Mean Transfer Factor of 1.064 and 0.94, respectively, for Pb and Cu), while Cr exhibited relatively lower bioavailability. The spatial distribution of heavy metal contamination and associated risks presented in this study will allow policymakers to pinpoint areas of intervention for remediation.

Penelitian ini bertujuan untuk menganalisis tingkat kesesuaian dan daya dukung wisata pantai di Pulau Penjalin, Kabupaten Kepulauan Anambas. Penentuan titik stasiun menggunakan teknik purposive sampling berdasarkan lokasi wisata pantai di Pulau Penjalin, Kabupaten Kepulauan Anambas. Untuk pengambilan data parameter ekologi dilakukan dengan metode survei. Hasil penelitian ini menunjukkan indeks kesesuaian wisata pantai di Pulau Penjalin pada stasiun 1 adalah  90,60% dan pada stasiun 2 adalah 97,44%, dengan tingkat kesesuaian wisata pantai pada kedua stasiun dikategorikan sangat sesuai. Daya dukung kawasan di Pulau Penjalin untuk aktivitas wisata pantai pada stasiun 1 sebanyak 478 jiwa dan dan stasiun 2 sebanyak 1.594 jiwa, dengan luas area pemanfaatan seluas 50 m2/orang dan waktu kunjungan selama 3 jam/orang/hari.

After a certain period or end-of-life (EoL), all the valuable products become waste if they are not properly managed. This study reveals the appropriate and sustainable pathway to manage the various solid wastes coming from used footwear (boots) of the Bangladesh Armed Forces and other Forces. The major parts separated from the collected four pair of used boots include leather, thermoplastic rubber (TPR) materials (e.g., sole, toe puff, stiffener, etc.), laces, metal shank, metal eyelet, etc. Careful observation of the used boots and its separated parts indicated 92-96% damage of the boots after the use of the boots for six months. Based on the properties of different parts of used boots, an integrated 4R’s waste management (reuse, recycle, recovery, and reduce) concept was introduced. It helps to minimize greenhouse gas, smog, heavy metals, dyes, pigments, and other pollutants emission to the atmosphere, thereby reducing the severe health consequences, environmental pollution, and climate change. This paper also discusses the critical aspects of various materials obtained from the post-consumer used boot through different mechanical, thermochemical, and chemical treatment processes.

Environmental issues are nowadays the prime concern worldwide for leather industries due to chrome containing solid and liquid wastes generated from the tannery. Therefore, experts are being encouraged in exploring alternative tanning agents. This study aimed at applying a novel vegetable tanning agent extracted from Xylocarpus granatum barks for the production of semi-chrome (SC) and chrome retanned (CR) leathers to reduce chromium use. Characterization of the SC and CR leathers was performed by Fourier Transform Infrared (FTIR) spectroscopy which revealed prominent tanning activity of the extracted tannins. The tanned leathers exhibited shrinkage temperatures of 112˚C for SC and 103˚C for CR leathers. The physicomechanical properties were found as tensile strength >230 kg/cm2, tear strength >30 kg/cm, grain cracking load >20 kg, distention at grain crack >7 mm, ball bursting load >38 kg, and distention at ball bursting >12mm that was comparatively acceptable according to UNIDO standard for shoe upper leathers.