Zahra Bitarafan
Research Scientist
Biography
My research areas are:
- Weed biology and control (chemical and non-chemical, IWM), mainly in cereal, oilseed, and protein crops
- Herbicide resistance
- Biology and control of invasive alien plant species
- Weed biodiversity in agricultural land
- Climate change and weeds in a changing climate
- (Others: pesticide residues in crops and food, medicinal plants, biochar, …)
"This page includes a subset of my research outputs published in English; the Norwegian version of this page provides a complete list of outputs in both English and Norwegian."
Abstract
Honey can be contaminated by various natural and anthropogenic substances, posing a health risk to consumers. Pyrrolizidine alkaloids (PAs) are naturally toxic compounds many plant species produce to protect against herbivores. Honey may become contaminated if bees collect nectar and pollen from PA-producing plants. Clopyralid is the active ingredient in some herbicides, including Matrigon 72 SG, approved for weed control in oilseed rape in several countries. As a systemic substance, its application before flowering may contaminate nectar, pollen, and honey. In 2023, 30 Norwegian honey samples were tested for the content of PAs and 22 other honey samples for clopyralid. Pyrrolizidine alkaloids were detected in 20 per cent of the samples, but predominantly at low levels (<12 μg kg−1). One sample contained a higher level (27.8 μg kg−1). Clopyralid was detected at levels exceeding the EU Maximum Residue Level (MRL) at the time (0.05 mg kg−1) and the current EU MRL (2024) (0.15 mg kg−1) in seven of 22 honey samples, including five honey samples produced close to clopyralid treated oilseed rape fields, one honey sample collected next to unsprayed fields, and in one sample received from a beekeeper. It was later clarified that beehives in proximity to unsprayed cropping areas with honey with a high clopyralid content also were close to conventional clopyralid-treated oilseed rape fields. The results indicate that a more extensive survey would be appropriate to evaluate whether PAs and clopyralid are a common problem in Norwegian honeybee products.
Abstract
No abstract has been registered
