Heavy metals like lead occur naturally in the environment, so it’s not unexpected to find traces of lead in our food supply. However, regular testing helps ensure we aren’t taking in unhealthy levels of lead.
The Australia New Zealand Food Standards Code specifies a maximum lead level for several foods, such as cereals, fruit, vegetables, honey, meat and fish. For other foods, the code states levels should be kept “as low as reasonably achievable”.
Testing by United States’ consumer advocacy organisation Consumer Reports has highlighted concerning levels of lead in some herbs and spices, dark chocolate and baby food.
We’re regularly asked how much lead is in our country’s food supply. So, in recent years, we’ve commissioned our own testing.
In 2022, we tested oregano, thyme and turmeric (20 products in total) for lead, arsenic and cadmium.
In 2024, we tested eight dark chocolate products for lead and cadmium.
All the samples we tested had detectable levels of lead. However, the independent toxicologist we checked with told us none were a safety concern.
Who monitors the food supply?
Every 5 to 7 years, New Zealand Food Safety (NZFS), a unit within the Ministry for Primary Industries, conducts the New Zealand Total Diet Study (NZTDS).
The NZTDS tests a range of foods sold in Aotearoa. It assesses our exposure to chemicals, environmental contaminants and nutrients.
The most recent study in 2016 tested more than 4,300 samples for 6 contaminants (aluminium, arsenic, cadmium, lead, mercury and tin).
NZFS told us the 2016 survey shows a continued decline in dietary lead. This corresponds with World Health Organization research findings.
The latest NZTDS is currently underway. It has a focus on infant and toddler diets.
Two rounds of testing have been completed. The first round found elevated levels of lead in two brands of ground cinnamon. NZFS told us cinnamon is a minor source of dietary lead due to the small amounts consumed.
NZFS said further testing and the full dietary exposure assessment will provide a more complete picture. It expects the full survey report to be published in mid-2026.
Study raises concerns about herbal medicines
In 2023, a significant increase in elevated blood lead levels was observed in people taking herbal medicines from the ancient Indian Ayurvedic medical system. Concerned by the trend, Health NZ | Te Whatu Ora commissioned testing to investigate further.
75 products were tested for the presence of nine heavy metals, including lead, arsenic, cadmium and mercury.
More than three-quarters (77%) of the products had detectable levels of at least one of the four contaminants.
Lead was detected in 67% of the products tested (levels ranged from 0.02mg/kg to 2.4mg/kg).
None of the products exceeded the World Health Organization (10mg/kg) and United States Pharmacopeia (5mg/kg) limits for lead.
13 products exceeded the limits for mercury (10 products), cadmium (2) and arsenic (1).
Action was taken to remove from sale in Aotearoa the products that exceeded the limits and posed a health risk.
Is lead lurking in your home?
Lead poisoning is a serious public health issue. We investigate where it might be hiding in your home, including in cosmetics and cheap tapware.
