Comments by Brian Shilhavy
Health Impact News Editor
A new study has been published out of Argentina showing how bee exposure to the herbicide glyphosate is affecting the development of honey bee broods.
Published in PLOS One , the title of the study is Glyphosate affects the larval development of honey bees depending on the susceptibility of colonies .
Most of the world’s bee supplies are used to pollinate crops by professional bee keepers. Previous studies have already confirmed that glyphosate is affecting the health of bees. See:
This current study from Argentina suggests the problem may be more serious than first known, as it is affecting bee larvae in bee broods as they develop, and not just adult bees.
It also means that most of the world’s honey supply is also contaminated with glyphosate, since most commercial honey products, including “local” honey, is the product of bees being used to pollinate crops. See:
Full Study here .
As the main agricultural insect pollinator, the honey bee (Apis mellifera) is exposed to a number of agrochemicals, including glyphosate (GLY), the most widely used herbicide.
Actually, GLY has been detected in honey and bee pollen baskets.
However, its impact on the honey bee brood is poorly explored. Therefore, we assessed the effects of GLY on larval development under chronic exposure during in vitro rearing.
Even though this procedure does not account for social compensatory mechanisms such as brood care by adult workers, it allows us to control the herbicide dose, homogenize nutrition and minimize environmental stress.
Our results show that brood fed with food containing GLY traces (1.25–5.0 mg per litre of food) had a higher proportion of larvae with delayed moulting and reduced weight. Our assessment also indicates a non-monotonic dose-response and variability in the effects among colonies.
Differences in genetic diversity could explain the variation in susceptibility to GLY. Accordingly, the transcription of immune/detoxifying genes in the guts of larvae exposed to GLY was variably regulated among the colonies studied.
Consequently, under laboratory conditions, the response of honey bees to GLY indicates that it is a stressor that affects larval development depending on individual and colony susceptibility.