Quantification and feed to food transfer of total and inorganic arsenic from a commercial seaweed feed

This study assesses the safety of using seaweed-based feed by examining how arsenic - commonly accumulated in brown seaweeds - transfers from feed to animal products and ultimately to human consumers. While seaweed feed contains measurable arsenic levels, the majority is present in organic forms, with the more toxic inorganic arsenic making up only a small fraction.
The findings show that after ingestion, arsenic is largely metabolized and excreted by livestock, resulting in very low transfer rates into meat, milk, eggs, and other products. As a result, estimated human exposure from consuming these products is negligible and well below established safety thresholds.
The study concludes that seaweed-based feed is safe from a human health perspective when used appropriately, with five years of commercial data demonstrating that human exposure risks are negligible, while noting that arsenic concentration can vary significantly based on the grain size of the seaweed meal.