Gunter Flipkens explains why everyone is worried about heavy metals leaching from olivine coastal weathering experiments. Then he explains how he tests the exact toxicity to animals, plus how to reduce it. Thesis link https://www.researchgate.net/publication/379406915_Coastal_enhanced_olivine_weathering_for_climate_change_mitigation_investigating_the_CO2_sequestration_potential_and_ecotoxicological_risks