text: Conium maculatum (Hemlock or Poison Hemlock), the most common of several species of hemlock noted for their toxicity. contains the alkaloids Coniine, N-methylconiine, conhydrine, pseudoconhydrine and g-coniceïne. The most important and toxic of these is Coniine. Coniine is a neurotoxin, which disrupts the workings of the central nervous system and is toxic to people and all classes of livestock.Conium maculatum has been introduced and naturalised in many other areas, including much of Asia, North America and Australia. Poison hemlock is often found on poorly drained soils, particularly near streams, ditches, and other surface water.