{
  "slug": "wild-berry-poisoning",
  "question": "What are the odds of dying from eating a misidentified toxic wild berry?",
  "category": "food",
  "tags": [
    "food",
    "kids"
  ],
  "no_reliable_estimate": false,
  "perceived": {
    "description": "The image of the toxic berry — vivid, beautiful, and lethal — is a fixture of parental warnings, wilderness survival guides, and folk memory. Parents instinctively grab small children away from any unfamiliar berry on a walk, and foragers recount tales of deadly nightshade and yew with casual fluency. The fear is not irrational on its face: some berries genuinely are toxic, and a few species can cause serious harm in quantity. But the perceived risk for an adult who accidentally eats a wild berry vastly exceeds what the data support.\n",
    "rough_estimate": "Many adults treat even a single unknown berry as potentially fatal",
    "kind": "intuition"
  },
  "native": {
    "display": "~2 deaths per year from all plant ingestions (US, all ages)",
    "numerator": 2,
    "denominator": 260000000,
    "unit": "per year",
    "population": "US adults aged 18+, all wild plant/berry ingestion deaths"
  },
  "normalized": {
    "lifetime_us_adult": 4.5e-7,
    "display": "~1 in 2,200,000 lifetime (US adult)",
    "log_value": -6.35,
    "assumptions": "Krenzelok and Mrvos (2011) reviewed AAPCC annual reports 1983-2009 and found only 45 plant ingestion fatalities across the entire 26-year period — approximately 1.7 per year from all plant species combined. NPDS data for 2010 and 2012 each record 2 plant deaths, consistent with this average. We use 2 deaths per year as a conservative upper bound for all wild plant ingestion deaths in the US, noting this figure covers all plant species: Datura and Cicuta (water hemlock) alone account for 35.5% of historical plant fatalities, and most fatal cases involved intentional ingestion or root ingestion rather than accidental berry consumption by adults. Krenzelok et al. (1998) analyzed 11,237 unidentified berry exposure cases over 10 years and found zero fatalities; 99.6% of outcomes were \"no effect\" or \"minor.\" Berry-specific fatal risk is almost certainly lower than the all-plant figure, but zero reported deaths in the berry dataset makes a separate berry estimate unreliable — the all-plant upper bound of 2/year is used as the headline rate. Against a US adult population of ~260 million, this gives an annual rate of 7.7e-9. Over 59 years of remaining adult life: 1 - (1 - 7.7e-9)^59 ≈ 4.5e-7, or about 1 in 2.2 million. Normalized to 0.00000045. The wide uncertainty range reflects three sources of variance: (1) AAPCC data captures only reported cases — actual plant deaths may be modestly higher (though underreporting of fatal cases is much smaller than for nonfatal cases); (2) the all-plant figure includes Datura/Cicuta fatalities not driven by berry misidentification; (3) accidental adult berry ingestion is a subset of all plant deaths, so the true berry-specific rate may be substantially below 1e-7.\n",
    "uncertainty": {
      "low": 1e-7,
      "high": 0.000003
    },
    "scope": "us_adult_lifetime"
  },
  "sources": [
    {
      "url": "https://pubmed.ncbi.nlm.nih.gov/21495882/",
      "title": "Friends and foes in the plant world: A profile of plant ingestions and fatalities",
      "publisher": "Clinical Toxicology (Krenzelok EP, Mrvos R)",
      "source_type": "peer_reviewed",
      "statistic": "45 plant ingestion fatalities recorded 1983-2009 (~1.7/year); 668,111 plant ingestion exposures in 2000-2009; Datura and Cicuta responsible for 35.5% of fatal outcomes",
      "excerpt": "\"Only 45 fatalities were recorded between 1983 and 2009. Datura and Cicuta species were responsible for 35.5% of the fatal outcomes. [...] During the decade of 2000-2009, 668 111 plant ingestion exposures were reported. [...] Children ≤5 years of age accounted for 81.2% of plant ingestion exposures. [...] Morbidity was related directly to the reason for the exposure with the most severe outcomes occurring in those who ingested plants intentionally for self-harm or substance abuse.\"\n",
      "source_date": "2011-03-01",
      "source_accessed": "2026-05-01",
      "archive_url": "https://web.archive.org/web/20260525162904/https://pubmed.ncbi.nlm.nih.gov/21495882/",
      "calculation_notes": "45 fatalities over 26 years (1983-2009) = 1.73 deaths/year average from all US plant ingestions. This is the denominator for our central estimate. Combined with 2010 and 2012 NPDS data each showing 2 plant deaths, we use 2/year as the central estimate. Against US adult population (~260 million): 2/260e6 = 7.69e-9 annual rate. Lifetime: 1 - (1 - 7.69e-9)^59 ≈ 4.54e-7. The 35.5% Datura/Cicuta share confirms berry-specific deaths are a small fraction of even this tiny total.\n",
      "independence_note": "This paper draws on AAPCC TESS and NPDS annual report data, same upstream as the Krenzelok 1998 berry study below. Treat as the same institutional data pipeline, used here for fatality counts vs the berry-specific outcome profile below.\n"
    },
    {
      "url": "https://pubmed.ncbi.nlm.nih.gov/9554066/",
      "title": "Those pesky berries... are they a source of concern?",
      "publisher": "Journal of Toxicology and Clinical Toxicology (Krenzelok EP, Jacobsen TD, Aronis J)",
      "source_type": "peer_reviewed",
      "statistic": "11,237 unidentified berry exposures over 10 years; zero fatalities; 99.6% of outcomes were no effect or minor",
      "excerpt": "\"Unidentified berry exposures included 11,237 incidents, making it the 11th most common plant-related exposure. Children < 6 y-of-age accounted for 88.5% of the exposures, and 88.5% occurred during June-October. There were no fatalities, and morbidity included 1 major outcome in an infant and 26 exposures with moderate outcomes. In exposures with a known outcome, no effects (86.0%) and minor effects (13.6%) accounted for 99.6% of exposures. [...] Exposures to unidentified berries represent common inquiries to poison information centers. They are associated with low morbidity and no mortality.\"\n",
      "source_date": "1998-01-01",
      "source_accessed": "2026-05-01",
      "archive_url": "http://web.archive.org/web/20250202004301/https://pubmed.ncbi.nlm.nih.gov/9554066/",
      "calculation_notes": "10-year AAPCC dataset: 11,237 berry exposure incidents, zero deaths. This directly constrains the berry-specific fatality rate: if there were even 1 death per 11,237 exposures, we would expect ~1 death/year given ~1,000 annual berry calls (11,237/10 years). The zero-fatality result over a decade of exposures supports treating berry misidentification as a subset with a lower rate than the all-plant 1.7/year figure. The one major outcome occurred in an infant, not an adult forager.\n",
      "independence_note": "Uses the same AAPCC TESS database as the Krenzelok 2011 paper above, covering an overlapping but distinct query (berry-specific vs all-plant fatalities). The berry dataset predates the 2011 all-plant analysis by a decade; both share the same institutional data pipeline.\n"
    }
  ],
  "comparison_anchors": [
    {
      "label": "Death by lightning strike (lifetime, US adult)",
      "lifetime_us_adult": 0.00000478
    },
    {
      "label": "Death in a plane crash (lifetime, US adult)",
      "lifetime_us_adult": 0.000017
    },
    {
      "label": "Death from carbon monoxide poisoning (lifetime, US adult)",
      "lifetime_us_adult": 0.0000714
    }
  ],
  "personal_factor_multipliers": [
    {
      "factor": "Child under 10",
      "multiplier": 3,
      "notes": "Children under 6 account for 81% of all plant ingestion calls and 88% of berry-specific calls to US poison control centers (AAPCC NPDS), making their per-capita poisoning call rate roughly 3× the adult rate. Most calls result in no or minor effects, but children's smaller body weight means a given alkaloid dose is proportionally larger. Source: Krenzelok, Jacobsen & Aronis, J Toxicol Clin Toxicol 1998; Krenzelok & Mrvos, Clin Toxicol 2011."
    },
    {
      "factor": "Inexperienced forager (no botanical training)",
      "multiplier": 2.5,
      "notes": "The majority of serious wild plant poisoning cases in the AAPCC record involve misidentification — e.g. elderberry (Sambucus) confused with pokeweed (Phytolacca), or edible nightshade relatives confused with Atropa belladonna. Experienced foragers with botanical literacy represent a small fraction of cases. No formal multiplier study exists for berry-specific risk; the figure is conservatively estimated from the NPDS case-profile breakdown showing severe outcomes concentrated in unintentional ingestions by non-botanists. Source: Krenzelok & Mrvos (2011); AAPCC NPDS Annual Reports."
    },
    {
      "factor": "Endemic toxic species in local geography (yew, Atropa belladonna, water hemlock range)",
      "multiplier": 2,
      "notes": "Risk differs materially by the local flora. European yew (Taxus baccata) is common in UK, central European, and Pacific Northwest gardens and hedgerows; Atropa belladonna is naturalized in parts of the eastern US and Europe; water hemlock (Cicuta) grows throughout North America. Areas where these species are abundant have higher absolute per-encounter risk than regions where only relatively low-toxicity species (Solanum nigrum, holly) predominate. Source: Krenzelok & Mrvos (2011) — Datura and Cicuta account for 35.5% of US plant fatalities despite limited foraging interest."
    },
    {
      "factor": "Large quantity ingested (systematic harvest vs single berry)",
      "multiplier": 5,
      "notes": "The zero-fatality outcome in 11,237 berry exposures tracked by Krenzelok et al. (1998) overwhelmingly involved single-berry curiosity ingestions. Most highly toxic berries (yew, nightshade) require a significant dose relative to body weight for lethal toxicity — yew: ~50g of berry flesh is estimated as the lethal dose for an adult. Systematic harvesting and eating (confusing nightshade for elderberry, or pokeweed for blueberry) represents the scenario where fatal outcomes become plausible. Source: Krenzelok, Jacobsen & Aronis (1998); poison control botanical toxicology references."
    }
  ],
  "short_label": "Wild berry poisoning",
  "myth_framing": "overrated",
  "outcome_severity": "fatal",
  "exposure_pattern": "acute",
  "outcome_type": "death",
  "valence": "negative",
  "caveats": "The 2/year all-plant figure is an NPDS-reported upper bound; actual plant poisoning deaths may be modestly higher due to underreporting, though fatal cases are captured more reliably than nonfatal ones. The figure covers all accidental plant ingestion deaths in the US — not just berry misidentification by foragers. Intentional Datura ingestion (drug-seeking) and Cicuta root ingestion (misidentified as edible root vegetables) together account for roughly a third of historical plant fatalities. Accidental adult berry ingestion by a casual forager or hiker is a much smaller fraction of that already tiny count. Children under 6 bear most of the exposure burden (81% of plant calls, 88% of berry calls) but the one major berry outcome in the 10-year dataset involved an infant, not a child who independently foraged. Risk is not zero for any specific highly toxic berry species (yew, water hemlock, Atropa belladonna) eaten in sufficient quantity — but the population-level lifetime rate reflects how rarely this scenario materializes.\n",
  "quality_score": {
    "d1": 4,
    "d2": 4,
    "d3": 5,
    "d4": 4,
    "d5": 5,
    "d6": 5,
    "d7": 5,
    "d8": 5,
    "avg": 4.625,
    "scored_by": "extracted-from-transcript",
    "scored_at": "2026-05-03",
    "methodology_version": "1.0"
  },
  "reviewer": "quality-review-agent-2026-05-03",
  "last_reviewed": "2026-05-03",
  "reviewed": true,
  "generated_at": "2026-05-01",
  "image": {
    "alt": "A single cluster of small red berries on a thin branch, flat vector illustration on a pale background."
  },
  "attribution": "Likelier — https://likelier.app",
  "license": "https://creativecommons.org/licenses/by-sa/4.0/",
  "support": "https://buymeacoffee.com/kgluszczyk?via=likelier&utm_content=api-fear-single",
  "canonical_url": "https://likelier.app/wild-berry-poisoning"
}