Distributions of Total Mercury and Methylmercury in Dragonflies from a Large, Abandoned Mercury Mining Region in China

Abstract

Dragon ies (Order Odonata) are often considered to be biosentinels of environmental contamination. Dragon ies (n = 439) belonging to 15 species of eight genera were collected from an abandoned mercury (Hg) mining region in China to investigate the bioaccumulation of total Hg (THg) and methylmercury (MeHg). The THg and MeHg concentrations in dragon ies varied widely within ranges of 0.06-19 mg/kg and 0.02-5.7 mg/kg, respectively. THg and MeHg were positively correlated with bodyweight (THg: r 2 = 0.10, P = 0.000; MeHg: r 2 = 0.09, P = 0.000). Signi cant variations were observed among species, with the highest MeHg value (in Orthetrum triangulare) being 5-fold higher than the lowest (in Pantala avescens). These variations were consistent with those of nitrogen isotope (δ 15 N) values. A health risk assessment found hazard quotients for specialist dragon y-consuming birds of up to 7.2, which is 2.4 times greater than the permissible limit of 3, suggesting a potential health risk of exposure.

Mercury Content in Soil Invertebrates of the Recreational Zone of a Large Industrial City (Cherepovets)

“…Отмеченный в настоящем исследовании большой размах между предельными концентрациями ртути у арахнид внутри одного биотопа, характерен для большинства хищных членистоногих Wu et al, 2021]. Это обусловлено как небольшой массой беспозвоночных и быстрым накоплением высоких концентраций, так и отсутствием эффекта биологического разбавления.…”

“…Беспозвоночные различного трофического статуса могут по-разному накапливать тяжелые металлы, в том числе ртуть [Gongalsky et al, 2007;Bouchelouche, Arab, 2020;Wu et al, 2021] Сенокосцев (Opiliones, Phalangidae) и пауков-волков (Aranei, Lycosidae) ловили с помощью почвенных ловушек. В каждом участке было установлено по 10 ловушек.…”

Characterizing the Movement of Per- and Polyfluoroalkyl Substances in an Avian Aquatic–Terrestrial Food Web

“…The diet of many species, including tree swallows, can involve invertebrates. Emergent aquatic macroinvertebrates can transfer contaminants from aquatic to terrestrial environments through food web interactions. − Aquatic invertebrate larvae develop in the benthic layer of freshwater streams where they can be exposed to contaminants via water, sediment, and plants. , During metamorphosis, some contaminants are retained in invertebrate tissues that, in addition to contaminants accumulated as adults, may be transferred when consumed as prey by predators, such as tree swallows. , Although several contaminants, including some PFAS, are known to move from aquatic to terrestrial biota within food webs, ,, the emergent macroinvertebrate pathway has not been investigated for the majority of PFAA precursors to date. One study has investigated the macroinvertebrate pathway for PFOSA and fluorotelomer sulfonate precursors, moving from water to plants and then terrestrial and aquatic invertebrates.…”