Kirsten Benkendorff, a marine science professor at Southern Cross University, recently purchased two punnets of blueberries from a supermarket in Coffs Harbour. After conducting tests in her lab, she discovered alarming levels of pesticides, including a long-banned toxic insecticide.

Benkendorff's initial tests revealed the presence of dimethoate, a pesticide that has been under scrutiny. This prompted the Australian Pesticides and Veterinary Medicines Authority (APVMA) to announce a review of dimethoate's use on berries. The APVMA stated that new data indicated Australians are consuming significantly more berries than in previous years. A recent survey showed berry consumption in Australia had surged between 285% and 962% since the last review in 2017.

The APVMA spokesperson noted that the findings did not suggest an immediate risk to consumers. However, Benkendorff's research indicated that even a small amount of blueberries could lead to exceeding the Acceptable Daily Intake (ADI) for children. Dimethoate is a neurotoxin that disrupts nerve function and has been classified as a possible human carcinogen by the U.S. Environmental Protection Agency.

In her tests, Benkendorff found that some blueberry samples contained dimethoate levels high enough for a 20-kilogram child to reach their daily safety threshold after consuming just a handful. While the samples were within legal limits, the levels raised concerns about potential health risks.

Additionally, Benkendorff detected thiometon, another pesticide banned in Australia since 2001, in several samples. Thiometon was found in six of eleven blueberry samples and in all five raspberry samples tested. Although the levels were low, Benkendorff expressed concern about how thiometon ended up in organic berries.

Marc Percival, a horticultural agronomist, suggested that the presence of thiometon could be due to spray drift or water contamination from neighboring properties. He noted that chemicals can travel significant distances through the air.

In response to the findings, Rachel Mackenzie, CEO of Berries Australia, ordered additional testing of samples from supermarkets. The results showed no thiometon and no pesticide residues exceeding legal limits.

Benkendorff's investigation into the berry industry stemmed from her interest in environmental issues affecting the Northern Rivers region. The area, once known for banana production, has seen a rapid increase in blueberry farming, now accounting for 86% of Australia's domestic blueberry supply.

Local residents have raised concerns about pesticide use, particularly in the Nambucca Valley Shire, where blueberry farms have proliferated in recent years. Raewyn Mackey, a resident, has been advocating for stricter pesticide regulations since a blueberry farm opened near her home. She reported difficulties in addressing her concerns with the state Environment Protection Authority (EPA), which stated it lacked sufficient evidence to take action against the farm.

The rapid growth of blueberry production in the region has led to a lack of clear records on the number of farms and the land they occupy. The Nambucca Valley Shire has acknowledged this gap in data, complicating efforts to monitor pesticide use and its impact on the environment.