Hexachlorobenzene

HCB, perchlorobenzene; formula: C6Cl6; CAS Registry Number: 118-74-1
Structure of hexachlorobenzene
Source: Wikipedia

Fungicide which was mainly used in seed treatment and as wood and timber preservative

Furthermore, it is a flame retardant and plasticiser. In pyrotechnics it is used in smoke munitions.  Hexachlorobenzene is the precursor of a number of compounds such as pentachlorophenol and is a by-product in the production of many plastics and solvents.
Due to its relatively high vapour pressure it is very mobile and found in all environmental compartments.

Environmentally relevant characteristics of hexachlorobenzene include:

Pesticides containing hexachlorobenzene are banned in the Federal Republic of Germany and the German Democratic Republic since 1981 and 1984, respectively.
When the Stockholm Convention entered into force in 2004, application of hexachlorobenzene was restricted to the use as chemical intermediate and as solvent for pesticides.

Specimen

Zebra mussel Common mussel species as invasive animal in rivers and lakes with high information level for water pollution
Bream Bioindicator in rivers and lakes
Suspended particulate matter Fine insoluble mineral or organic particles in the water phase
Eelpout As the only viviparous fish in German nearshore waters, it is a bioindicator in nearshore coastal marine ecosystems.
Herring gull Inshore, the herring gull mainly feeds from the sea: upon fish, mussels, and crabs.
Roe deer, one-year-old The roe deer is the most common of the larger herbivores (first order-consumer) to be found in the wild in Europe.
Feral pigeon A pigeon species home in nearly every city.
Earthworm (Aporrectodea longa) As an organism living at ground level, it is a major driver of the decomposition of organic material (e.g. plant litter).
Earthworm (Lumbricus terrestris) As an organism living at ground level, it is a major driver of the decomposition of organic material (e.g. plant litter).
Soil Soil is livelihood and biosphere for humans, animals, plants and soil organisms. All the substances brought in are transported, transformed and/or accumulated in the soil.
Students Student groups with an even number of female and male students at the age of 20 to 29.

Sampling area

BR/NP Berchtesgaden The only high mountains national park in Germany and an area of the Limestone Alps with international relevance
Saarländischer Verdichtungsraum Important, old-industrialised conurbation in Germany.
Bornhöveder Seengebiet Main water divide between the North- and Baltic Sea
Rhein Longest river in Germany
NP Bayerischer Wald Germany's first national park
NP Vorpommersche Boddenlandschaft National Park in the largest brackish water (Bodden) habitat of the world.
BR/NP Wattenmeere National park in the world largest connected sand and mud flats.
Elbe Fourth largest river basin in Central Europe
Verdichtungsraum Halle-Leipzig Region in the chemical triangle of Central Germany
NP Harz Germany's largest forest national park
Solling Second highest and largest low mountain range in Northern Germany
BR Pfälzerwald Germany's largest connected forest area in a range of low mountains
Oberbayerisches Tertiärhügelland The Upper Bavarian Tertiary Uplands are a part of the Southern German Molasse Basin
Donau Second largest river in Europe
Sampling sites (humans) 4 university cities as sampling areas.

Sampling period

1985 - 2018