Short Wave (NPR) — "Why Legal Weed Isn’t Always Safe"

Air Date: October 14, 2025
Host: Regina Barber
Guests:

• Theresa Carr, Independent Health and Science Journalist
• Sydney Lupkin, NPR Pharmaceuticals Correspondent

Overview: The Hidden Risks of Legal Cannabis

This episode investigates the patchwork state-by-state regulation of legal cannabis in the US and highlights emerging health risks from contaminants such as mold, pesticides, and heavy metals. Host Regina Barber is joined by science journalists Theresa Carr and Sydney Lupkin, who share findings from recent investigations about why legal weed isn’t always as safe as consumers might assume. The guests discuss personal stories, regulatory gaps, scientific uncertainties, and practical advice for cannabis users.

Key Discussion Points and Insights

1. Cannabis Consumption and Unseen Risks ([00:53]–[03:45])

• Personal Story: Theresa Carr shares the case of Summer Parker, an Oklahoma medical marijuana professional with chronic pain, who switched from opioids to cannabis for relief. Summer and her partner experienced unexplained health problems, including fainting and migraines ([01:44]).
• Contamination Discovery: When cannabis products the couple were using were tested, "to their horror, they discovered that they were contaminated with both mold and some pesticides and that those pesticides were associated with some neurotoxicity" (Theresa Carr, [02:56]).

Memorable Quote:
"When they stopped using that weed and switched to another brand, the problems that they had dissipated. So that's all you can say. They feel strongly that the two are correlated."
— Theresa Carr ([05:50])

2. The Patchwork of State Regulations ([04:20]–[06:59])

• Federal vs. State Oversight: Sydney Lupkin explains, "Weed on the federal level is illegal. Pharmaceuticals… have to be approved by the Food and Drug Administration... With weed, that robust federal system is not there, which means that the states are basically having to figure this all out on their own." ([04:42])
• State Collaboration: States formed a group called CANRA to facilitate communication about regulation, but "the standards are still kind of a patchwork" ([05:22]).

Notable Moment:
Theresa Carr discusses a lab manager in Oklahoma who found that "most [of 20 tested joints] were tainted with mold, two of them actually had salmonella, and about 3/4... overstated the THC level." ([06:21])

• Regulatory Failures: Contaminated products are reaching shelves; regulators struggle to keep products clean ([06:36]).

3. Testing Incentives and Industry Challenges ([06:59]–[08:48])

• Perverse Incentives: Producers pay for their own product testing, so there's motivation to choose labs with lax standards:
  "Producers will choose labs that are looser about passing products for contaminants, and that will give them higher THC levels. The flip side... labs that are strict about their standards... lose business." — Theresa Carr ([07:08])
• Case Studies—Oregon & California:
  • Oregon opened a state testing lab and cracked down on THC inflation ([08:17]).
  • California’s DCC tracks cannabis from plant to product, but recalls and pesticide issues persist ([08:56]–[09:37]).

Memorable Quotes:
"The labs have sort of had to keep up with this... creative industry where... now we've got THC popcorn on the shelves. Like, how do you test that?"
— Sydney Lupkin ([09:24])

"In 2024, there were over 60 weed recalls, and then this year, they've already had 80 weed recalls, and it's only October, and they've taken 10 actions against laboratories so far this year."
— Sydney Lupkin ([09:58])

4. National Study: Regulatory Gaps and Scientific Unknowns ([10:14]–[11:40])

• ASU Professor Maxwell Long’s 2022 study found over 600 regulated contaminants across 30 states, but each state tested for only 60–120.
• "A state that might be testing for 300 things might not be testing for the one thing that is guaranteed to give you cancer someday." — Sydney Lupkin ([11:08])
• Research is limited because cannabis remains federally illegal, impeding understanding of health impacts.

5. Health Concerns: Mold, Metals, and Pesticides ([11:40]–[13:26])

• Inhalation risks are greater than ingestion; contaminants go straight to the lungs and bloodstream ([11:40]).
• Some molds can cause serious lung issues, especially in immunocompromised users.
• Organophosphate pesticides, sometimes found on cannabis, are linked to faster Parkinson’s disease progression—a major issue as "about 40% of Parkinson’s patients use cannabis" ([12:20]–[13:26]).

6. Consumer Advice and Harm Reduction ([13:26]–[14:42])

• Best Practices:
  • Buy from licensed dispensaries: Legal products undergo at least some testing.
  • Avoid illicit cannabis: Failed or contaminated products are often sold illegally.
  • Check state recall lists and know local regulations ([13:34]–[14:42]).

Notable Quotes:
"My best advice I can give people, even though it's imperfect, is to go to a dispensary and get a product through the legal market that has been through some sort of testing."
— Theresa Carr ([13:34])

"If you care about the people... growing your weed, it's nice to go legal. And... familiarize yourself with what your state regulations are and... regularly check recall lists."
— Sydney Lupkin ([14:03])

Timestamps of Important Segments

• 00:53 — Introduction to episode topic
• 01:11 — Summer & Charles’s story of contaminated weed
• 02:56 — Discovery of mold and pesticides in legal products
• 04:42 — How cannabis regulation differs from pharmaceuticals
• 06:21 — Oklahoma’s widespread contamination findings
• 08:17 — Oregon’s regulatory efforts
• 08:56 — California’s regulatory systems and recall record
• 10:14 — Nationwide study on regulatory inconsistencies
• 11:40 — Why inhaled contaminants are especially concerning
• 12:20 — Health effects: mold, metals, and pesticides
• 13:34 — Advice for consumers
• 14:42 — Episode wrap-up

Tone & Notable Moments

• The episode balances consumer concern and scientific inquiry, blending real stories (Summer and Charles) with a light, curious tone.
• Lively banter and easy-to-follow explanations help demystify complicated regulatory systems.

Summary Table: Main Risks Highlighted

| Contaminant Type | Health Risk | Regulatory Issue | |-----------------------|--------------------------------------------------|----------------------| | Mold | Respiratory issues, pneumonia for some users | Not consistently screened across states | | Pesticides (e.g., Organophosphates) | Neurotoxicity, possible link to Parkinson’s | Varying standards, under-researched | | Heavy Metals | Various (depends on the metal) | Inconsistent testing | | Salmonella | Infection risk | Testing lapses detected |

This episode underscores that while legalization aims for safer access, regulatory, economic, and scientific realities make “legal” weed not always “safe” weed. Consumers are encouraged to buy licensed, tested products and stay informed about recalls and local laws—until federal oversight or better science can catch up.