Slugs are soft-bodied, legless creatures, generally described as snails without a large external shell. These gastropod molluscs navigate their environment using a muscular foot, leaving behind a characteristic trail of mucus. This article clarifies whether slugs are toxic and outlines associated risks to family and pets.
Understanding Slug Defenses
Slugs produce a layer of mucus, which serves several important biological functions. This slime is primarily water, making up 90% to 99.7% of its composition, with the remaining portion consisting of proteins, sugars, salts, enzymes, and other compounds like hyaluronic acid and antimicrobial peptides. The mucus facilitates movement, allowing slugs to glide over surfaces while protecting their delicate skin from dehydration and physical damage. While generally not harmful upon contact, its appearance and sticky texture might contribute to a misconception of danger. Some slug species do produce mucus containing anesthetic or toxic components to deter predators, making them unpalatable.
Direct Risks to Human Health
Direct contact with slugs is generally not considered harmful. Slugs can carry bacteria and other pathogens on their bodies due to their environment, so washing hands thoroughly after handling them is recommended. Accidental ingestion, while rare, doesn’t mean the slug is inherently poisonous. However, consuming raw slugs can pose significant health risks because they can carry various parasites and bacteria, such as Listeria monocytogenes or E. coli. The primary concern is parasitic worm transmission.
Indirect Risks to Pet Health
Slugs can pose an indirect risk to pets, particularly dogs, by acting as intermediate hosts for parasites. The primary concern is rat lungworm (Angiostrongylus cantonensis), a parasitic worm that lives in rats. Slugs and snails become infected by ingesting larvae passed in rat feces. Pets, especially curious dogs, can become infected by eating infected slugs or snails, or by ingesting larvae from their slime trails on toys, water bowls, or plants.
Once ingested, the rat lungworm larvae can migrate through the pet’s body. In dogs, these larvae can travel to the brain, spinal cord, and peripheral nerves, leading to neurological signs such as extreme pain, hind limb weakness, paralysis, or even meningitis. Other symptoms may include vomiting, diarrhea, coughing, breathing problems, loss of appetite, and weight loss. While treatable, rat lungworm can be life-threatening if not identified promptly. Cats are thought to have some natural protection due to their tendency to vomit after ingesting such larvae.
Safety and Prevention Strategies
To minimize risks from slugs, employ several safety and prevention strategies for both humans and pets. For human health, practice good hygiene by washing hands thoroughly with soap and water after gardening or contact with slugs. Rinse all fresh produce, especially leafy greens, rigorously under running water before consumption to remove slug slime or hidden slugs.
For pet safety, preventing slug and snail ingestion is paramount. Supervise pets outdoors, particularly in areas where slugs are prevalent, and discourage them from eating slugs, snails, or contaminated items like toys or grass. Regularly clean outdoor pet food and water bowls, bringing them indoors overnight to prevent contamination by slugs and their slime. Consult a veterinarian about regular monthly parasite control to protect pets against lungworm. If a pet is suspected of ingesting a slug, seek immediate veterinary attention. Avoid using slug baits containing metaldehyde, as these are highly toxic to pets.