A Survey from 2015 to 2019 to Investigate the Occurrence of Pesticide Residues in Dead Honeybees and Other Matrices Related to Honeybee Mortality Incidents in Italy

Abstract

Honeybee health can be compromised not only by infectious and infesting diseases, but also by the acute or chronic action of certain pesticides. In recent years, there have been numerous reports of colony mortality by Italian beekeepers, but the investigations of these losses have been inconsistent, both in relation to the type of personnel involved (beekeepers, official veterinarians, members of the police force, etc.) and the procedures utilized. It was therefore deemed necessary to draw up national guidelines with the aim of standardizing sampling active ties. In this paper, we present the results of a survey carried out in Italy from 2015 to 2019, following these guidelines. Residues of 150 pesticides in 696 samples were analyzed by LC-MS/MS and GC-MS/MS. On average, 50% of the honeybee samples were positive for one or more pesticides with an average of 2 different pesticides per sample and a maximum of seven active ingredients, some of which had been banned in Europe or were not authorized in Italy. Insecticides were the most frequently detected, mainly belonging to the pyrethroid group (49%, above all tau-fluvalinate), followed by organophosphates (chlorpyrifos, 18%) and neonicotinoids (imidacloprid, 7%). This work provides further evidence of the possible relationship between complex pesticide exposure and honeybee mortality and/or depopulation of hives.

A study on lethal doses of various pesticides on honeybees (Apis mellifera L.) – a laboratory trial

“…Martinello et al . (2020) stated that pesticides exposure is directly related to honeybee mortality in Italy. About 150 pesticides residues were found in dead honeybee samples.…”

Lethal and Sublethal Effects of Pyriproxyfen on Apis and Non-Apis Bees

“…A survey performed in Italy from 2015 to 2019 revealed that among the 696 samples of dead honey bees analyzed, 0.8% included pyriproxyfen with concentrations ranging from 3.7 to 5.9 ng/bee [ 137 ]. On the contrary, among 17 samples of dead honey bees analyzed by Calatayud–Vernich et al [ 134 ], two (11.8%) included residues of pyriproxyfen at concentrations of 4 µg/kg and 558 µg/kg.…”

The Honey Bee: An Active Biosampler of Environmental Pollution and a Possible Warning Biomarker for Human Health

“…During flights and foraging activity, their hair-covered body causes electrical charge accumulation on its surface due to friction with the air, favoring the attraction of airborne substances, including pollen and pollutants [15,16]. During foraging flights, honey bees collect pollen, nectar, plant resins, honeydew and water, which are taken into the hive and stored, being at the same time also valid "samplers" of organic and inorganic chemicals in the environment, which they bring back to the colony [17,18]. Finally, they are easy insects to breed, having modest dietary needs and being almost ubiquitous [19].…”