Snails picked up by the river are polluted by various items (such as domestic wastewater, industrial wastewater and chemical residues). Snails' food is microorganisms in sludge, so there may be some non-degradable chemical components in wild snails. Wild snails are not recommended to be eaten. If they are not handled properly, they may cause poisoning.

Oncomelania generally refers to molluscs of Oncomelania, belonging to Gastropoda Oncomelania. Snails are distributed in most parts of China. Snails require higher water quality and produce less. You can catch it in summer and autumn. China snails are very common in fresh water. Snails are dioecious. The method of sex identification of snails is mainly based on the shape of their right antenna. The right antenna of the male snail bends inward to the right (the bent part is the male genitalia). In addition, the female snail is big and round, and the male snail is small and long. Oncomelania hupehensis is an oviparous animal, and its reproduction mode is unique. The embryonic development and larval development of Oncomelania hupensis are completed in the mother body. It takes about a year for a fertilized egg to give birth to a small snail. Oncomelania hupensis lays eggs in batches and begins to breed in March-April every year. At the same time of producing young snails, the male and female parents mate and fertilize, and at the same time, the young snails to be produced in the next year are propagated in the mother. A mother snail can produce about 100 ~ 150 young snails every year.