Brown slugs are a common sight in gardens, prompting concerns about their potential danger to humans and pets. While not inherently poisonous, their risks involve indirect threats rather than direct toxicity. Understanding these nuances can help ensure safety for families and their animal companions.
Understanding Slug Toxicity
Most common brown slugs are not considered poisonous or venomous to humans or pets through touch or accidental ingestion. They do not possess fangs or stingers to inject venom, and their bodies do not produce acutely toxic compounds. While some slugs may secrete defensive slime, this mucus is rarely severely harmful or fatal. It might cause minor skin irritation in sensitive individuals due to its salt and acid content.
The concern surrounding slugs stems from what they might carry, not their direct biological makeup. Slugs are detritivores, consuming decaying plant matter and animal feces. This diet exposes them to environmental contaminants. Therefore, the primary dangers associated with slugs are from external pathogens they can harbor.
Potential Health Risks Beyond Direct Toxicity
The most significant health concerns associated with slugs come from parasites and bacteria they carry. Slugs can serve as intermediate hosts for parasites like the rat lungworm (Angiostrongylus cantonensis). This parasite completes its life cycle in rats, but its larvae can develop in slugs after ingesting rat feces containing the parasite’s eggs. Humans can become infected by accidentally ingesting these infected slugs, or by consuming unwashed produce contaminated with their slime trails.
In humans, rat lungworm can cause eosinophilic meningitis, an infection of the brain and spinal cord. Symptoms range from mild headaches and neck stiffness to more severe neurological issues, and in rare instances, it can be fatal. For dogs, ingestion of infected slugs can lead to lungworm (Angiostrongylus vasorum), a condition that can cause respiratory, cardiovascular, and neurological problems, and may be life-threatening if untreated.
Beyond parasites, slugs can carry bacteria, including Salmonella and E. coli. These bacteria can be transmitted if a slug or its slime contacts food consumed without proper washing. This highlights the importance of hygiene when handling garden produce or after any contact with slugs.
What to Do After Contact
If skin contact occurs with a slug, wash hands thoroughly with soap and warm water. This simple action significantly reduces the risk of transferring any potential pathogens. While slug slime itself is not inherently dangerous, it can carry contaminants.
If a human or pet has ingested a slug, monitoring for symptoms is important. For humans, if symptoms like severe headaches, stiff neck, nausea, or fever develop, seek medical attention immediately. For pets, particularly dogs, symptoms such as coughing, lethargy, vomiting, diarrhea, or unusual neurological signs warrant an immediate call to a veterinarian. It is advised against inducing vomiting without professional guidance.
Safe Handling and Prevention
Minimizing contact with slugs is a practical approach to reduce risks. When gardening, wearing gloves provides a physical barrier against direct contact with slugs and their slime. Thoroughly wash all fruits and vegetables, especially those grown close to the ground, before consumption. Washing individual leaves of produce under cold running water helps remove slugs or their residue.
For pet owners, discouraging pets from playing with or eating slugs is a preventative measure. Keeping food and water bowls indoors or washing them regularly if used outside helps prevent slugs from contaminating them. Tidying away pet toys from the garden overnight also helps, as slugs can crawl over them and leave slime trails containing larvae. Using pet-safe slug control methods, such as iron phosphate baits, helps manage slug populations without posing a risk of poisoning from toxic chemicals like metaldehyde, which are highly dangerous to pets.