Talc Cancer Risk UK Case, Sword Dragon Ichthyosaur, Ant-driven Yogurt, and Atlas Interstellar Comet — Naked Scientists

British consumers are pursuing a legal action against Johnson & Johnson over talc-based products possibly linked to ovarian cancer, with experts noting asbestos contamination risks and the need for robust safety testing. Scientists describe a new ichthyosaur species, the sword dragon of Dorset, revealing ancient predation marks and a rare Pleinsbachian-era specimen. In a culinary science twist, researchers show ants can coagulate milk into yogurt through microbial activity and formic acid, inspiring new fermentation possibilities. On the sky, comets Swan and Lemon may be visible together, along with the interstellar Atlas, offering a rare celestial show. The episode also answers how UV sunscreen works, detailing organic and inorganic filters and real-world risk context.

Talc Powder and Cancer Risk: UK Case and Scientific Perspective

The episode opens with British consumers taking legal action against Johnson & Johnson, alleging long-term talc use in products like baby powder may be linked to ovarian cancer and other health issues. Experts explain talc is a naturally occurring mineral used across industries to absorb moisture and soften products, including cosmetics. They highlight the contamination risk when talc minerals are mined near asbestos, a known carcinogen. Regulators enforce safety testing for cosmetics, and researchers note that evidence for uncontaminated talc causing cancer in humans remains limited, emphasizing the need for large, well-adjusted studies. Views are placed in perspective: even if a risk is confirmed, it would likely be far smaller than that from smoking, given the small amounts of talc in consumer products and how rarely they are used.

Quote: "the amounts are so small and you're probably using these products not that often" - Sophia Lowes

Sword Dragon Ichthyosaur: A New Dorset Dinosaur Relative

Paleontologists announce a new ichthyosaur species, the sword dragon of Dorset, from England’s Jurassic coast. The specimen, roughly 185 million years old and from the Pleinsbachian stage, displays unique skull and flipper features that place it within the Leptonectidae family. The discovery, traced from a 2001 find near Charmouth, includes evidence of old injuries and possible predation by a larger ichthyosaur, making it one of the best-preserved and most informative Pleinsbachian marine reptiles. The discussion clarifies that ichthyosaurs are reptiles, not dinosaurs, despite their dolphin-like appearance and apex-predator lifestyle. The team emphasizes the specimen’s status as a nearly complete early Jurassic marine reptile, offering a dramatic window into ancient seas.

Quote: "this is the most complete marine reptile ever found in the Pleinsbachian" - Dean Lomax

Ant-driven Yogurt: Fermenting with Microbes from Ants

Researchers describe a Danish-led study inspired by traditional yogurt fermentation techniques involving ants. Bacteria from ants, including lactic and acetic acid bacteria, along with formic acid used by ants for defense, enrich the milk environment to kickstart fermentation. Lab experiments with sterile milk and local ants demonstrated how these microbes and formic acid can influence yogurt texture and tang, with lab-grown versions achieving yogurt-like flavors that are more acidic and lemony. The researchers note the potential to extend the approach to other dairy and plant-based substrates, including ice cream, panna cotta, and cocktails, and even to plant-based yogurts and cheeses, opening pathways for novel fermentation techniques reliant on insect-associated microbes and warm, nest-like incubators for flavor development.

Quote: "the formic acid from the ants was entering into the yogurt and likely made a more favorable environment" - Veronica Sinnott

Comets in the Sky: Swan, Lemon, and Atlas

Astronomers discuss a rare alignment of comets Swan and Lemon visible in the night sky, with Atlas—the third known interstellar comet—passing through the inner solar system. Long-period comets originate far beyond the Kuiper Belt, heating up as they approach the Sun and developing a visible coma and tail. Atlas, being interstellar, follows a hyperbolic trajectory, not bound to the Sun, offering clues about materials and conditions from other star systems. Observers are advised to look west after sunset for Lemon and Swan in different hemispheres, with Atlas requiring dark skies and clear conditions to spot as it travels through the inner solar system. The discussion also highlights mission plans like the European Comet Interceptor to study such visitors up close.

Quote: "Interstellar comets can tell us what lies beyond our solar system" - Sarah Russell

Sun Protection Science: How Sunscreen Works

In the question of the week, the host explains how UV filters in sunscreen protect skin. Sunscreens use organic molecules that absorb UV energy and convert it to heat, and inorganic filters such as zinc oxide that absorb and scatter UV light. The discussion covers photostability, the differences between organic and inorganic filters, and how various organisms have evolved natural sunscreens, including seaweed compounds called mycosporine-like amino acids that protect tissues sensitive to UV. The segment ties these ideas to real-world skin protection and ongoing research into more effective, stable, and inclusive sun protection strategies.

Quote: "UV radiation from the sun damages DNA" - Anthony Young

Context and Next Steps

The episode weaves together public health debates, fossil discoveries, innovative food science, and space observations to illustrate how science touches everyday life and the broader universe. Viewers are invited to follow updates on the talc case, the Sword Dragon ichthyosaur, continued ant-based fermentation research, and upcoming space missions that might further illuminate the origins of our solar system and beyond.