<p>Every Wednesday UPSC Essentials releases a concise revision of three current themes that frequently appear in the UPSC Prelims. This edition (2026) focuses on <span class="key-term" data-definition="Phytoremediation — use of plants (including hyperaccumulator species) to extract or stabilize contaminants from soil; relevant to GS4: Environment">Phytoremediation</span>, the pricing tactic of <span class="key-term" data-definition="Shrinkflation — practice of reducing product size/quantity while keeping price unchanged, a hidden form of inflation; GS3: Economy">shrinkflation</span>, and the marine phenomenon of <span class="key-term" data-definition="Bioluminescence — biological emission of light via enzymatic reaction within organisms, common in marine ecosystems; GS4: Environment">bioluminescence</span>. Understanding these concepts helps aspirants answer fact‑based questions with precision.</p> <h3>Key Developments</h3> <ul> <li>India’s Mulund dumpsite bio‑remediation is stalled, highlighting the need for alternative methods such as <span class="key-term" data-definition="Hyperaccumulator — plant that can accumulate heavy metals at concentrations 100–1000 times higher than typical plants; GS4: Environment">hyperaccumulator</span> plants.</li> <li>West‑Asia conflict‑driven input cost spikes have prompted FMCG firms to adopt <span class="key-term" data-definition="Shrinkflation — practice of reducing product size/quantity while keeping price unchanged, a hidden form of inflation; GS3: Economy">shrinkflation</span> across items like instant noodles, juice packs and even automotive components.</li> <li>Bioluminescent bays (e.g., Puerto Rico, Toyama Bay) continue to attract attention, while UPSC frequently tests the underlying enzymatic mechanism versus the related <span class="key-term" data-definition="Biofluorescence — absorption of short‑wavelength light and re‑emission at longer wavelength by living organisms; GS4: Environment">biofluorescence</span> concept.</li> </ul> <h3>Important Facts</h3> <p>• <span class="key-term" data-definition="Phytoremediation — use of plants (including hyperaccumulator species) to extract or stabilize contaminants from soil; relevant to GS4: Environment">Phytoremediation</span> can remove metals such as Cd, Ni, Pb, Zn, As and even certain radionuclides. The process involves four steps: selection of native species, root uptake, translocation to aerial parts, and harvest/disposal.</p> <p>• Advantages: low capital cost, solar‑driven, improves soil organic matter, and prevents erosion. Limitations: slow (10+ years), cannot treat organic pollutants, and risk of invasive species if non‑native plants are used.</p> <p>• <span class="key-term" data-definition="Shrinkflation — practice of reducing product size/quantity while keeping price unchanged, a hidden form of inflation; GS3: Economy">Shrinkflation</span> is a micro‑economic response to supply‑side shocks; it differs from <span class="key-term" data-definition="Stagf