Mould growth in lunchbox lids can compromise food safety and cause health risks, especially for vulnerable populations. Frequent cleaning is crucial. Have you ever seen black spots inside the lid of your plastic lunchbox or water bottle and ignored them, thinking they won't do you any harm? In an Instagram video posted on July 8, Neethu Sureshkumar, a microbiologist working in Dubai, explained how that seemingly harmless black spot can be dangerous to your health.Don't ignore the black spots in your lunchbox lid.Also Read | BMC leptospirosis alert: What it is, precautions after exposure to Mumbai's waterlogged streets, 72-hour golden windowCheck your lunchbox lid today!According to the microbiologist, the black spots found beneath the rubber gaskets of your lunchbox lids are mould growth, and they pose several hidden health hazards. She revealed that these fungal colonies thrive on trapped moisture and food remains, posing risks such as digestive distress or allergic reactions to vulnerable individuals.Sharing a cautionary message in the video, the microbiologist stated, “If you see black spots inside your lunchbox lid, don't ignore them. Those black spots you see under the rubber seal of your lunchbox lid are usually mould, a type of fungus that grows in warm, damp places where moisture and tiny food particles get trapped.”“As a microbiologist, let me tell you, they can contaminate your food,” she further warned. Furthermore, she cautioned that if one keeps using the same lunchbox without cleaning it properly, mould spores can transfer to the food.How do the mould spores harm your health?According to the microbiologist, the mould spores, if not cleaned properly, may cause an upset stomach, allergies, or other health problems, especially in children, older adults, and people with weakened immune systems.To ensure food safety, she advised frequently disinfecting the removable seals using hot, soapy water and ensuring they are entirely dry before reassembly. Here are the steps you should be following to thoroughly clean your lunchbox lids:Remove the rubber gasket regularly.Wash it with hot, soapy water.Dry it completely before putting it back.Store your lunchbox with the lid slightly open. Maintaining a dry storage environment with the lid open serves as a critical final step in preventing future contamination.But what happens if the dark stains persist after scrubbing? The microbiologist said that, then, it is essential to replace the rubber gaskets on your lunchbox lids to prevent the spread of harmful spores. “If the black spots don't come off after cleaning, replace the rubber seal or the lid. A clean lunchbox means safer food,” she added.Note to readers: This article is for informational purposes only and not a substitute for professional medical advice. Always seek the advice of your doctor with any questions about a medical condition.This report is based on user-generated content from social media. HT.com has not independently verified the claims and does not endorse them.Neethu Sureshkumar, based in Dubai, UAE, is currently a microbiologist at GMG. She has done an MSc in Microbiology from Bharathiar University.Krishna Priya Pallavi is a journalist with over 9 years of experience, covering health, fashion, pop culture, travel, wellness, entertainment, festivals, mental health, art, decor, fitness, and sex and relationships. She is an alumna of the Indian Institute of Mass Communication (IIMC), Dhenkanal, and holds an undergraduate degree in Journalism and Mass Communication from Guru Gobind Singh Indraprastha University, Delhi. Her strong academic foundation informs her analytical and detail-oriented approach to storytelling, helping her uncover stories where none seem to exist.