what toxic material does it have?
High concentrations of heavy metals and PCBs
Giant Pacific octopus
Dr. Roland Anderson, an octopus specialist, found high concentrations of heavy metals and PCBs in tissues and digestive glands. He suggests that these high concentrations were obtained from their preferred prey, red rock crab ("Cancer productus"). 
what group of animals do octopus belong to Molluscs how big do they grow? Adults usually weigh around 15 kg (33 lb), with an arm span of up to 4.3 m (14 ft). how many limbs do they have? Eight what is the largest of its kind? The giant Pacific octopus where is this type normally found? The coastal North Pacific, along California, Oregon, Washington, British Columbia, Alaska, Russia, Japan, and Korean Peninsula. what does it feed on? Shrimp, crabs, scallop, abalone etc. how long do they normally live? Typically 3–5 years in the wild. what is a threat that it faces? Scavengers and other organisms often attempt to eat octopus eggs; preyed upon by many other zooplankton and filter feeders, harbor seals, sea otters, and sperm whales.
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Giant Pacific octopus [SEP] Toxins
Dr. Roland Anderson, an octopus specialist, found high concentrations of heavy metals and PCBs in tissues and digestive glands. He suggests that these high concentrations were obtained from their preferred prey, red rock crab ("Cancer productus"). These crabs bury themselves in contaminated sediments and eat prey that live nearby. What effects these toxins have on octopuses are unknown, but other exposed animals have been known to show liver damage, changes in immune systems, and death.