# AI tells a user that frozen tuna is safe to eat raw because freezing kills parasites, ignoring scombroid poisoning risk

- **ID:** `food-safety/frozen-fish-scombroid`
- **Domain:** food-safety
- **Category:** health_risk
- **Error Code:** `FS-FISH-SCOMBROID-021`
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

Scombroid poisoning is caused by histamine produced by bacteria in tuna, mackerel, and mahi-mahi when fish is improperly stored above 40°F (4°C) before freezing; freezing does not destroy histamine, which is heat-stable and not removed by cooking.

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| FDA Fish and Fishery Products Hazards and Controls Guide 2022 | active | — | — |
| NOAA Seafood Inspection Program 2023 | active | — | — |

## Workarounds

1. **Advise user to only consume raw tuna from suppliers that provide a cold chain log showing the fish was kept below 40°F from catch to freezing. Provide a Python script to parse a temperature log: `if max_temp > 40: print('Risk of scombroid')`.** (80% success)
   ```
   Advise user to only consume raw tuna from suppliers that provide a cold chain log showing the fish was kept below 40°F from catch to freezing. Provide a Python script to parse a temperature log: `if max_temp > 40: print('Risk of scombroid')`.
   ```
2. **If user must eat raw tuna, recommend flash-frozen at sea within 2 hours of catch, and check for a certificate of histamine testing (<50 ppm). Offer a URL to NOAA's fish storage guidelines.** (70% success)
   ```
   If user must eat raw tuna, recommend flash-frozen at sea within 2 hours of catch, and check for a certificate of histamine testing (<50 ppm). Offer a URL to NOAA's fish storage guidelines.
   ```

## Dead Ends

- **Tell user to smell the fish; if it smells fine, it's safe** — Histamine does not have a distinct odor; fish can smell fresh but still contain dangerous levels of histamine. (95% fail)
- **Suggest the fish be cooked to 145°F to destroy histamine** — Histamine is heat-stable and remains toxic even after cooking to 145°F; cooking only kills bacteria, not the toxin. (85% fail)
- **Recommend buying 'sushi-grade' frozen fish** — 'Sushi-grade' is a marketing term; it only indicates that the fish was frozen to kill parasites, but does not guarantee proper temperature control to prevent histamine formation. (75% fail)