News from CRIS: In the News - Toxic Cookies?
March 17, 2025
Top Takeaways:
- Detection ≠ danger: modern testing can detect substances at incredibly tiny levels, but presence alone doesn’t mean harm.
- Dosage matters: a person would need to eat thousands of cookies daily over a lifetime to reach concerning levels for most detected substances.
- Water and food limits differ and using water safety standards for food leads to misleading conclusions.
What claims are trending in the news and on social media?
In December 2024, an organization sent 25 Girl Scout cookie samples to a laboratory for analysis. The laboratory detected trace levels of glyphosate, a commonly used herbicide, along with heavy metals such as arsenic, cadmium, lead, and mercury.
The organization leveraged the report to claim that children were being exposed to toxic levels of contaminants. The alarming nature of these claims quickly gained traction, causing it to trend in the news and across social media.
Is there merit to the claims that the Girl Scout cookies are toxic?
As with anything, the dose makes the poison. In theory, consuming large quantities of these cookies over an extended period could lead to harm, but in reality, the amounts we eat are too small to pose a significant concern for most of the cookies. Let’s break it down.
How many cookies would we need to consume to cause harm?
Using available averages, we estimated how many cookies a child aged 6-11 weighing 31.8 kg (70 lb) would need to consume in a single sitting every day over a lifetime before potential health effects might occur.
- Glyphosate – 73,953 cookies
- Cadmium – 52 cookies
- Mercury – 412 cookies
- Arsenic – 20.4 cookies
- Aluminum – 92.4 cookies
Lead is a little trickier because there is significant variability in the testing data. Most importantly, unlike most regulated compounds, lead lacks a reference dose and instead has an Interim Reference Level (IRL) of 2.2 μg total per day for children, which is not body weight-based.
- Lead (lowest detected lead level) – 194.52 cookies
- Lead (average detected lead level) – 15.3 cookies
- Lead (highest detected lead level) – 4.14 cookies
While these compounds are detectable, a person would need to consume an unrealistically large number of cookies over an extended period to reach levels associated with adverse health effects.
Does the detection of these contaminants mean they are harmful?
The detection of a substance does not mean it poses harm. Modern testing methods are incredibly sensitive and capable of detecting substances at parts per trillion (ppt) or smaller concentrations. The mere presence of glyphosate or heavy metals does not indicate a meaningful health risk.
For example, metals are a natural part of our soil, and plants take up small amounts of metals during the natural growing process. We cannot eliminate all metals and maintain the nutritional density of food; metals, even some heavy metals, play an essential part role in our biological processes.
Furthermore, regulatory agencies like the FDA, EPA, and EFSA set exposure limits based on rigorous scientific evaluations (not a single person’s professional opinion), incorporating substantial safety margins. If the detected levels are far below established safety thresholds, there is no cause for concern, no matter how concerning it may sound in an article.
...
To continue reading the entire blog post, visit: https://cris.msu.edu/news/in-the-news/in-the-news-toxic-cookies/.