Wild pigs are turning up with ‘neon blue’ flesh in California. Authorities sound the alarm

First reported by the Los Angeles Times – August 5, 2025

A disturbing discovery in Monterey County, California has prompted state officials to issue a public warning after wild pigs were found with vibrant blue muscle and fat tissue — a rare indicator of rodenticide contamination. The phenomenon has raised serious concerns about wildlife safety, food contamination, and the unintended consequences of pest control measures used in agricultural areas.

Wildlife control professionals in the Salinas region initially reported the incident after capturing multiple pigs displaying the unnatural tissue color. Lab testing later confirmed the presence of diphacinone, an anticoagulant rodenticide, in the animals' liver and stomach contents.

A Hidden Danger in the Food Chain

Rodenticides like diphacinone are commonly used in agricultural fields to manage rodent populations such as squirrels and rats. These poisons are often dyed for easy identification — typically in vivid colors like blue or green — which can inadvertently attract larger animals, including wild pigs. Officials noted that the blue pigmentation found in the pigs is likely a result of direct consumption of bait or secondary exposure by ingesting contaminated prey.

While the chemical is designed to be slow-acting and generally lethal after multiple feedings in small rodents, it can accumulate in the tissues of larger animals over time. In this case, the pigs appeared to be asymptomatic despite harboring significant levels of the toxin. That’s especially concerning, as contaminated animals may be consumed by predators — or, in some cases, donated for human consumption — before symptoms ever appear.

Health Risks to Humans and Wildlife

Studies have shown that cooking meat tainted with diphacinone does little to reduce toxicity, meaning human exposure remains a risk even if the contaminated meat is thoroughly prepared. In some cases, symptoms of poisoning in both humans and animals include lethargy, internal bleeding, and other signs of anticoagulant toxicity.

The California Department of Fish and Wildlife emphasized that blue coloration is a potential, but not guaranteed, indicator of poisoning. The absence of visible signs doesn't rule out contamination — making it critical for hunters and wildlife managers to remain vigilant.

A 2018 study cited by the department found that approximately 8.3% of wild pigs tested in California carried residues of anticoagulant rodenticides, suggesting that exposure is more widespread than isolated cases imply.

Regulatory Response and Public Safety

Under California law, the use of diphacinone is now restricted, with applications limited to licensed vector control personnel, government agencies, and approved agricultural operations. The law, which went into effect in 2024, aims to reduce wildlife exposure following mounting evidence of ecological harm.

In response to the incident, the agricultural firm associated with the contaminated pigs has reportedly removed bait stations from their fields. Officials are now urging trappers and hunters to report any sightings of wildlife with discolored tissue and to avoid consumption of any animal suspected to be contaminated.

What to Do If You Encounter Blue-Tinged Meat

The California Department of Fish and Wildlife encourages anyone who observes blue tissue or fat in wild pigs or other game animals to contact their Wildlife Health Lab

This case underscores the need for greater awareness around the use of rodenticides and their unintended effects on non-target species. As California continues to battle the ecological impact of chemical pest control, this incident serves as a stark reminder that what’s used to eliminate one pest can pose risks across the entire food chain.

See original article: https://www.latimes.com/california/story/2025-08-05/exposure-to-rat-poison-turns-meat-of-wild-pigs-blue-authorities-in-monterey-county-warn