Tea Safety: Lead In Tea
As far back as Roman times, lead has been known to cause health problems. In more modern times, lead paints, lead pipes, and leaded gasoline increased lead exposure until legislation curbed this usage. As a result of legislation and related public health initiatives, the prevalence of elevated Blood Lead Levels (10 or more micrograms/dL) decreased from 77.8% of the population in the mid-1970’s to 2.2% in the early 1990’s.
Back in 2013, some lab testing and investigative reporting revealed some teas contain some levels of lead. Here are some of the key points to keep in mind regarding lead in tea:
Blood Lead Levels (BLL) of 5 micrograms per deciliter or less can result in adverse effects
The CDC indicates lead exposure at low levels can have adverse effects on the cardiovascular system, kidneys, and cognitive functions.
Lead testing can be done in different ways
While the method is not specifically stated in the article, it is likely the tea samples were burned, and the lead measurements revealed elements trapped in the leaf. Burning tea leaves is different from steeping tea leaves in water. One report in particular points this out:
…the study found that there was no real prospect of a health concern from the lead. The liquid portions of the teas that were brewed and tested contained very little if any [lead]…
A small fraction of lead in or on tea leaves is transferred during steeping
Qualified Testing and Certification Help Reassure Consumers of the Already Low-Risks Associated with Tea
The Tea Association of the US has issued a statement, reminding consumers that lead can be a naturally occurring element, that agricultural products will naturally contain trace levels of lead, and also refers to this guidance from the FDA.
Guidance also requires standardized testing and transparency of test results. In the sample test results below, lead (Chinese character: 铅) results were 0.49mg per kg, or 0.49 parts per million (ppm). Given that approximately 20% of the lead in dry leaf form is passed to the tea liquor, a resulting 0.098 ppm of lead could be found in tea liquor if 1 kg of dry leaf was infused. When considered on a per-cup (2-5 grams) basis, the amount of lead present becomes miniscule.
In short, drinking tea poses about as much risk of lead exposure as eating spinach or breathing air. If it were to become a greater concern, the first line of defense is consistent and transparent testing results. This is why Firsd Tea and its parent company, Zhejiang Tea Group work to maintain such high standards of quality and safety for our teas.