Background Mosquito-borne diseases like dengue and malaria are a significant public health burden. Commercial repellents and larvicides can be expensive, contain chemicals, and contribute to plastic waste. Citrus peels (from oranges, lemons, etc.) are common kitchen waste containing essential oils (like limonene) that are known to be insecticidal. This project studies the efficacy of repurposing this waste as a natural larvicide, offering a sustainable approach to vector control. Hypothesis An extract derived from waste orange peels (Citrus sinensis) is not effective in killing mosquito larvae compared to an extract from lemon peels (Citrus limon) or a commercial chemical larvicide. Objectives To prepare extracts from dried waste orange and lemon peels using a simple distillation method. To identify and collect mosquito larvae (genus Aedes or Culex) from local stagnant water bodies. To test the efficacy of the citrus extracts in killing the larvae compared to a control and a commercial product. To propose a model for sustainable waste-to-wellness management at the community level. Methodology Field Study and Preparation- Larvae Collection- Using a dipper or a small mug, carefully collect mosquito larvae and pupae from stagnant water sources (like unused pots, ditches). Place them in a wide bowl with some of the same water for observation. Peel Extract Preparation- Collect peels from consumed oranges and lemons. Sun-dry them for 3-4 days until they become brittle. Crush them into a coarse powder. Simple Distillation- Place the crushed peel in a round-bottom flask. Add water and heat gently using a spirit lamp. Connect the flask to a condenser (a long glass or metal tube running through a bowl of cold water). The condensed vapour will contain the essential oil and will be collected in a beaker. This is the extract to be tested. This can be done in the school lab. Bioassay Experiment- Take 4 clear glass beakers. Add 100 ml of water and introduce 10 healthy larvae into each beaker using a dropper. Treatment Beaker 1: Add 1 ml of orange peel extract. Beaker 2: Add 1 ml of lemon peel extract. Beaker 3: Add 1 ml of a commercial chemical larvicide (positive control). Beaker 4: Add 1 ml of distilled water (negative control). Observation- Observe the beakers every 30 minutes for 4-6 hours. Record the time at which larvae stop moving (are dead) in each beaker. Calculate the percentage mortality for each treatment after a fixed time period (e.g., 4 hours). Expected Outcome The study will provide mortality rates for larvae exposed to different citrus extracts. It is expected that the orange peel extract will show significant larvicidal activity, potentially comparable to the commercial product. A protocol for creating an effective larvicide from kitchen waste will be established. Significance This project demonstrates an example of "wealth from waste," turning an environmental problem (kitchen waste) into a solution for a public health problem (mosquito control). It reduces reliance on chemicals and plastic-packaged products, promotes a circular economy, and utilizes ecosystem principles for sustainable well-being. It is a low-cost, accessible innovation for local communities. Source : Science and Innovation for Sustainability - Activity Guide Book 2026 & 2027