Lithium contamination of honeybee products and its accumulation in brood as a consequence of anti-varroa treatment

Abstract

This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Changes in Lithium Levels in Bees and Their Products Following Anti-Varroa Treatment

“…Lithium concentration decreased in all body parts of the bees from day 4 post-treatment ( Table 2 , Figure 2 ). This pattern may be consistent with the findings of Prešern and colleagues , who revealed that in bee larvae, lithium level started to drop on day 3 post-treatment [ 15 ]. By day 22 post-treatment, lithium level showed full recovery to the pre-treatment control level (0.15 mg kg −1 on average; Figure 2 ).…”

“…Feeding lithium syrup at a concentration (25 mM) applied in earlier studies [ 9 , 15 , 20 ] resulted in an average lithium peak of 130.13 mg kg −1 (average of the hives) in bees’ bodies (thorax and abdomen), with an absolute maximum value of 167.71 mg kg −1 in hive 1, on day 4. Lithium concentration decreased in all body parts of the bees from day 4 post-treatment ( Table 2 , Figure 2 ).…”

“…Interestingly, however, beneficial effects of lithium on longevity were detected in adult individuals of Drosophila [ 14 ]. For both honeybee adults and brood, adverse effects on the longevity of lithiated sugar syrup administration is reported but restricted mainly to in vitro trials [ 9 , 15 ]. Furthermore, it is of note that a freely moving bee might react differently to aversive compounds.…”

“…Lithium chloride (PubChem CID: 433294) may provide an effective, commercially available, and relatively cheap alternative, and therefore, it may be increasingly applied as an unregulated veterinary medicine [ 16 , 17 , 18 , 19 ]. Despite its potential to treat varroosis in the short term, only a few studies are dealing with the consequences of lithium treatments on honey and other bee products [ 15 , 20 ]. However, with honey and beeswax being the most remarkable hive products worldwide, human exposure to lithium when it is used needs to be extensively studied in the apiculture-related food chain to evaluate its impacts before it ever becomes a registered veterinary medicine.…”

Neurostatistical approach to toxicological testing in honeybees

“…Calculating slope within moving window allows taking into the account both excitation and suppression of normal activity, as demonstrated on fish data or insect olfaction [4] , with length of the window adjustable to the rate of firing. We have adopted the method for the purpose of evaluating the impact of bioactive substance – in our case lithium [3] – on the honeybee colony. With the proposed method the investigator avoids absolute numbers in natural mortality and thus makes colonies comparable among themselves.…”