Heavy metals on honeybees indicate their concentration in the atmosphere. a proof of concept

Abstract

The aim of this research was to evaluate as a proof of concept, a quantitative relationship between atmospheric particulate matter (PM 10 ), atmospheric heavy metals (Pb, Ni and Cd) and Pb, Ni and Cd concentrations accumulated on bees reared in a beehive in the urban territory in Milan. For this purpose, a beehive called the Honey Factory, located in the Triennale museum area in Milano, was considered in the trial from May to October 2015. Every two days, bees found dead in the beehive were collected and the concentration of lead, cadmium and nickel on the bees bodies were evaluated through atomic absorption analysis. In the same period, data about atmospheric dust, Lead, Cadmium and Nickel, were daily downloaded by the ARPA website. The comparison between atmospheric and animal data has revealed a tight relation. Linear regressions for animals and atmosphere were calculated: when the concentration of atmospheric lead exceeded the value of 4 ng/m3, bees 'carried' about 0.7 mg/kg of lead. When the lead atmospheric concentration was higher than 15 ng/m3, lead on the bee's body was more than 0.9 mg/kg (y ¼ 0.1006x þ 0.573, R 2 ¼ 0.98). A similar relationship was detected for Nickel. This study showed that heavy metals accumulated on honeybees depend on the atmospheric concentrations measured during the month before animal sampling and that PM 10 pollution level seems to contribute to Pb and Ni levels detected on the animals. HIGHLIGHTSBees are environmental quality indicators. Pb, Ni, Cd (HM) were detected on bees and in the air. HM on bees depend on the atmospheric concentration. ARTICLE HISTORY

Pollutants and Their Interaction with Diseases of Social Hymenoptera

“…Among the pollutants, pesticides used in agriculture have gained the most attention because pollinators visit crop plants or wild flowers growing near arable fields and are confronted with those chemicals when collecting food ( Figure 1) [59][60][61][62]. Heavy metals are a second group of pollutants that may threaten social insects in agricultural regions, but also in more urbanized or industrial areas [31,35,[63][64][65][66][67][68][69][70][71]. Heavy metals are present in soils (either naturally or due to pollution) and can potentially lead to contamination of the nests of social insects, or they may move up the food chain ( Figure 2).…”

“…Also, other herbivorous insects serving as prey for social wasps may accumulate these pollutants, which may result in the increased exposure of these predatory wasps to heavy metals [35,36,47,63,65,[68][69][70][71][72][73][74][75][76][77][78][79][80]. Pesticides (or their residues) and heavy metals, as well as other pollutants from combustion, traffic, agriculture, and coal mining, can also form or bind to fine particulate matter [66,[81][82][83][84][85][86][87][88][89][90][91] that pollutes the air. Eventually, fine particulate matter settles on surfaces, such as insect cuticles [88,89] or flowers [92] (Figure 2).…”

“…In social insects and especially honeybees, the collection of fine particulate matter during foraging translates into an accumulation of xenobiotics in honey and beebread. Comparisons between apiaries have often shown higher levels of residues of pesticides, heavy metals, and other particulate matter in the bees themselves or honey in urbanized or industrialized areas in comparison to rural areas [32,66,70,210,219,220].…”

“…However, especially fine particulate matter levels have been shown to be elevated in urban areas [86], and honey bees have been shown to accumulate airborne particulate matter from a cement factory and traffic on their body surfaces in highly polluted areas [88,89]. Such particulate matter may thus contribute to enhanced disease susceptibility and mortality of social insects [66,69]. While this is correlative evidence that higher levels of airborne pollution may have negative effects on insect health, a few studies have attempted to uncover the effects more directly.…”

Honeybee products as potential bioindicators of heavy metals contamination from Northern Vietnam

“…The honeybee is considered a good biological indicator to assess the environmental condition through the presence of pollutant in their products (Fakhimzadeh et al, 2005;Perugini, 2009). In the world, this issue has been mainly conducted on Apis mellifera Linnaeus, 1758 (Costa et al, 2019;Goretti et al, 2020;Naccari et al, 2014;Perna et al, 2012;Perugini et al, 2011;Popescu et al, 2010;Porrini et al, 2014;Ruschiono, 2013;Vincevica-Gaile et al, 2012;Zhelyazkova, 2012) and limited on Apis cerana Fabricius, 1793 (Manzoor et al, 2013). Apis cerana Fabricius, 1793 is one of the main honeybees species used in beekeeping farms in Vietnam (Pham, 2014;Phung, Vu, 1999).…”